Merge pull request #4 from erp-mafia/export-biz

Export biz

.claude/settings.local.json

@@ -26,7 +26,18 @@
       "Bash(git commit:*)",
       "WebFetch(domain:raw.githubusercontent.com)",
       "WebFetch(domain:support.fortnox.se)",
-      "Bash(npx vitest run:*)"
+      "Bash(npx vitest run:*)",
+      "WebFetch(domain:www.bjornlunden.se)",
+      "WebFetch(domain:www.scb.se)",
+      "WebFetch(domain:stripe.com)",
+      "WebFetch(domain:tullify.se)",
+      "WebFetch(domain:www.momsens.se)",
+      "WebFetch(domain:www.bokforingstips.se)",
+      "WebFetch(domain:rattsakuten.se)",
+      "WebFetch(domain:www.faronline.se)",
+      "WebFetch(domain:www.worldstopexports.com)",
+      "WebFetch(domain:www.riksbank.se)",
+      "WebFetch(domain:www.avalara.com)"
     ]
   }
 }

app/api/customers/[id]/route.ts

@@ -2,6 +2,10 @@ import { createClient } from '@/lib/supabase/server'
 import { NextResponse } from 'next/server'
 import { validateBody } from '@/lib/api/validate'
 import { UpdateCustomerSchema } from '@/lib/api/schemas'
+import { validateVatNumber } from '@/lib/vat/vies-client'
+import { createLogger } from '@/lib/logger'
+
+const log = createLogger('api/customers/[id]')
 
 export async function GET(
   request: Request,
@@ -95,6 +99,56 @@ export async function PATCH(
     return NextResponse.json({ error: error.message }, { status: 500 })
   }
 
+  // Auto-validate VAT number when it changes on an EU business customer (non-blocking)
+  const isEuBusiness = (body.customer_type || data.customer_type) === 'eu_business'
+  if (body.vat_number !== undefined && isEuBusiness) {
+    try {
+      if (body.vat_number) {
+        const vatResult = await validateVatNumber(body.vat_number)
+        if (vatResult.valid) {
+          await supabase
+            .from('customers')
+            .update({
+              vat_number_validated: true,
+              vat_number_validated_at: new Date().toISOString(),
+            })
+            .eq('id', id)
+            .eq('user_id', user.id)
+
+          data.vat_number_validated = true
+          data.vat_number_validated_at = new Date().toISOString()
+        } else {
+          await supabase
+            .from('customers')
+            .update({
+              vat_number_validated: false,
+              vat_number_validated_at: null,
+            })
+            .eq('id', id)
+            .eq('user_id', user.id)
+
+          data.vat_number_validated = false
+          data.vat_number_validated_at = null
+        }
+      } else {
+        // VAT number cleared
+        await supabase
+          .from('customers')
+          .update({
+            vat_number_validated: false,
+            vat_number_validated_at: null,
+          })
+          .eq('id', id)
+          .eq('user_id', user.id)
+
+        data.vat_number_validated = false
+        data.vat_number_validated_at = null
+      }
+    } catch (err) {
+      log.warn('Auto-VIES validation failed on customer update:', err)
+    }
+  }
+
   return NextResponse.json({ data })
 }
 

app/api/customers/route.ts

@@ -4,8 +4,12 @@ import { eventBus } from '@/lib/events'
 import { ensureInitialized } from '@/lib/init'
 import { validateBody } from '@/lib/api/validate'
 import { CreateCustomerSchema } from '@/lib/api/schemas'
+import { validateVatNumber } from '@/lib/vat/vies-client'
+import { createLogger } from '@/lib/logger'
 import type { Customer } from '@/types'
 
+const log = createLogger('api/customers')
+
 ensureInitialized()
 
 export async function GET() {
@@ -68,6 +72,28 @@ export async function POST(request: Request) {
     return NextResponse.json({ error: error.message }, { status: 500 })
   }
 
+  // Auto-validate VAT number for EU business customers (non-blocking)
+  if (body.customer_type === 'eu_business' && body.vat_number) {
+    try {
+      const vatResult = await validateVatNumber(body.vat_number)
+      if (vatResult.valid) {
+        await supabase
+          .from('customers')
+          .update({
+            vat_number_validated: true,
+            vat_number_validated_at: new Date().toISOString(),
+          })
+          .eq('id', data.id)
+          .eq('user_id', user.id)
+
+        data.vat_number_validated = true
+        data.vat_number_validated_at = new Date().toISOString()
+      }
+    } catch (err) {
+      log.warn('Auto-VIES validation failed on customer create:', err)
+    }
+  }
+
   await eventBus.emit({
     type: 'customer.created',
     payload: { customer: data as Customer, userId: user.id },

app/api/extensions/export/currency-receivables/report/route.ts

@@ -0,0 +1,156 @@
+import { createClient } from '@/lib/supabase/server'
+import { NextResponse } from 'next/server'
+import { fetchAllRows } from '@/lib/supabase/fetch-all'
+import {
+  generateReceivablesReport,
+  type ReceivableInvoice,
+  type ReceivableCustomer,
+  type GLLine,
+  type ExchangeRateInfo,
+} from '@/extensions/export/currency-receivables/lib/receivables-engine'
+import { fetchMultipleRates } from '@/lib/currency/riksbanken'
+import type { Currency } from '@/types'
+
+const SUPPORTED_CURRENCIES: Currency[] = ['EUR', 'USD', 'GBP', 'NOK', 'DKK']
+const FX_ACCOUNTS = ['3960', '7960']
+
+/**
+ * GET /api/extensions/export/currency-receivables/report
+ *
+ * Generate a multi-currency receivables report showing FX exposure,
+ * unrealized gains/losses, and realized FX from GL.
+ *
+ * Query params:
+ *   year (optional) — Year for realized FX trend (default: current year)
+ */
+export async function GET(request: Request) {
+  const supabase = await createClient()
+  const { data: { user } } = await supabase.auth.getUser()
+
+  if (!user) {
+    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+  }
+
+  const { searchParams } = new URL(request.url)
+  const yearStr = searchParams.get('year')
+  const year = yearStr ? parseInt(yearStr, 10) : new Date().getFullYear()
+
+  if (isNaN(year) || year < 2000 || year > 2100) {
+    return NextResponse.json({ error: 'Invalid year' }, { status: 400 })
+  }
+
+  const referenceDate = new Date().toISOString().split('T')[0]
+
+  try {
+    // Fetch open foreign-currency invoices
+    const invoices = await fetchAllRows<ReceivableInvoice>(({ from, to }) =>
+      supabase
+        .from('invoices')
+        .select('id, invoice_number, invoice_date, due_date, status, currency, total, total_sek, exchange_rate, customer_id')
+        .eq('user_id', user.id)
+        .in('status', ['sent', 'overdue'])
+        .neq('currency', 'SEK')
+        .range(from, to)
+    )
+
+    // Fetch customers
+    const customerIds = [...new Set(invoices.map(inv => inv.customer_id))]
+    let customers: ReceivableCustomer[] = []
+    if (customerIds.length > 0) {
+      const { data: customerData } = await supabase
+        .from('customers')
+        .select('id, name, country')
+        .eq('user_id', user.id)
+        .in('id', customerIds)
+
+      customers = (customerData || []) as ReceivableCustomer[]
+    }
+
+    // Fetch current Riksbanken rates for all supported currencies
+    const rateMap = await fetchMultipleRates(SUPPORTED_CURRENCIES)
+    const currentRates: ExchangeRateInfo[] = []
+    for (const [, rate] of rateMap) {
+      if (rate.currency !== 'SEK') {
+        currentRates.push({
+          currency: rate.currency,
+          rate: rate.rate,
+          date: rate.date,
+        })
+      }
+    }
+
+    // Fetch realized FX GL lines for the year
+    const realizedFXLines = await fetchFXLines(supabase, user.id, year)
+
+    const report = generateReceivablesReport({
+      invoices,
+      customers,
+      currentRates,
+      realizedFXLines,
+      referenceDate,
+      year,
+    })
+
+    return NextResponse.json({ data: report })
+  } catch (err) {
+    console.error('Error generating currency receivables report:', err)
+    return NextResponse.json(
+      { error: err instanceof Error ? err.message : 'Failed to generate report' },
+      { status: 500 },
+    )
+  }
+}
+
+/**
+ * Fetch GL lines on accounts 3960 (FX gains) and 7960 (FX losses)
+ * for posted journal entries in the given year.
+ */
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+async function fetchFXLines(supabase: any, userId: string, year: number): Promise<GLLine[]> {
+  const startDate = `${year}-01-01`
+  const endDate = `${year}-12-31`
+
+  // Get posted journal entry IDs in the year
+  const { data: entries, error: entriesError } = await supabase
+    .from('journal_entries')
+    .select('id, entry_date')
+    .eq('user_id', userId)
+    .eq('status', 'posted')
+    .gte('entry_date', startDate)
+    .lte('entry_date', endDate)
+
+  if (entriesError || !entries || entries.length === 0) return []
+
+  const entryDateMap = new Map<string, string>()
+  for (const e of entries as Array<{ id: string; entry_date: string }>) {
+    entryDateMap.set(e.id, e.entry_date)
+  }
+
+  const entryIds = entries.map((e: { id: string }) => e.id)
+
+  // Fetch lines in batches
+  const BATCH_SIZE = 200
+  const allLines: GLLine[] = []
+
+  for (let i = 0; i < entryIds.length; i += BATCH_SIZE) {
+    const batch = entryIds.slice(i, i + BATCH_SIZE)
+    const { data: lines } = await supabase
+      .from('journal_entry_lines')
+      .select('journal_entry_id, account_number, debit_amount, credit_amount')
+      .in('journal_entry_id', batch)
+      .in('account_number', FX_ACCOUNTS)
+
+    if (lines) {
+      for (const line of lines as Array<{ journal_entry_id: string; account_number: string; debit_amount: number; credit_amount: number }>) {
+        allLines.push({
+          account_number: line.account_number,
+          debit: Number(line.debit_amount) || 0,
+          credit: Number(line.credit_amount) || 0,
+          entry_date: entryDateMap.get(line.journal_entry_id) || startDate,
+        })
+      }
+    }
+  }
+
+  return allLines
+}

app/api/extensions/export/eu-sales-list/download/route.ts

@@ -0,0 +1,166 @@
+import { createClient } from '@/lib/supabase/server'
+import { NextResponse } from 'next/server'
+import { fetchAllRows } from '@/lib/supabase/fetch-all'
+import {
+  generateECSalesListReport,
+  getMonthPeriod,
+  getQuarterPeriod,
+  type ECSalesListInvoice,
+  type ECSalesListCustomer,
+  type GLAccountTotal,
+} from '@/extensions/export/eu-sales-list/lib/eu-sales-list-engine'
+import { generateCSV, generateCSVFilename } from '@/extensions/export/eu-sales-list/lib/csv-generator'
+import { generateSKVXml, generateXMLFilename } from '@/extensions/export/eu-sales-list/lib/skv-xml-generator'
+
+/**
+ * GET /api/extensions/export/eu-sales-list/download
+ *
+ * Download an EC Sales List (periodisk sammanställning) as CSV or XML.
+ *
+ * Query params:
+ *   year     (required) — Fiscal year
+ *   month    (optional) — 1-12, for monthly filing
+ *   quarter  (optional) — 1-4, for quarterly filing
+ *   format   (required) — 'csv' or 'xml'
+ */
+export async function GET(request: Request) {
+  const supabase = await createClient()
+  const { data: { user } } = await supabase.auth.getUser()
+
+  if (!user) {
+    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+  }
+
+  // Parse query parameters
+  const { searchParams } = new URL(request.url)
+  const yearStr = searchParams.get('year')
+  const monthStr = searchParams.get('month')
+  const quarterStr = searchParams.get('quarter')
+  const format = searchParams.get('format')
+
+  if (!yearStr) {
+    return NextResponse.json({ error: 'year is required' }, { status: 400 })
+  }
+
+  if (!format || !['csv', 'xml'].includes(format)) {
+    return NextResponse.json({ error: 'format is required and must be csv or xml' }, { status: 400 })
+  }
+
+  const year = parseInt(yearStr, 10)
+  if (isNaN(year) || year < 2000 || year > 2100) {
+    return NextResponse.json({ error: 'Invalid year' }, { status: 400 })
+  }
+
+  if (!monthStr && !quarterStr) {
+    return NextResponse.json({ error: 'Either month or quarter is required' }, { status: 400 })
+  }
+
+  if (monthStr && quarterStr) {
+    return NextResponse.json({ error: 'Provide either month or quarter, not both' }, { status: 400 })
+  }
+
+  let month: number | undefined
+  let quarter: number | undefined
+
+  if (monthStr) {
+    month = parseInt(monthStr, 10)
+    if (isNaN(month) || month < 1 || month > 12) {
+      return NextResponse.json({ error: 'Invalid month' }, { status: 400 })
+    }
+  }
+
+  if (quarterStr) {
+    quarter = parseInt(quarterStr, 10)
+    if (isNaN(quarter) || quarter < 1 || quarter > 4) {
+      return NextResponse.json({ error: 'Invalid quarter' }, { status: 400 })
+    }
+  }
+
+  const period = month !== undefined
+    ? getMonthPeriod(year, month)
+    : getQuarterPeriod(year, quarter!)
+
+  try {
+    // Fetch company settings
+    const { data: company, error: companyError } = await supabase
+      .from('company_settings')
+      .select('company_name, org_number, vat_number')
+      .eq('user_id', user.id)
+      .single()
+
+    if (companyError || !company) {
+      return NextResponse.json({ error: 'Company settings not found' }, { status: 404 })
+    }
+
+    const reporterVatNumber = company.vat_number || `SE${(company.org_number || '').replace(/\D/g, '')}01`
+
+    // Fetch invoices
+    const invoices = await fetchAllRows<ECSalesListInvoice>(({ from, to }) =>
+      supabase
+        .from('invoices')
+        .select('id, invoice_number, invoice_date, status, currency, total, total_sek, subtotal, subtotal_sek, vat_treatment, moms_ruta, document_type, credited_invoice_id, customer_id')
+        .eq('user_id', user.id)
+        .gte('invoice_date', period.start)
+        .lte('invoice_date', period.end)
+        .in('status', ['sent', 'paid', 'overdue'])
+        .eq('vat_treatment', 'reverse_charge')
+        .range(from, to)
+    )
+
+    // Fetch customers
+    const customerIds = [...new Set(invoices.map(inv => inv.customer_id))]
+    let customers: ECSalesListCustomer[] = []
+    if (customerIds.length > 0) {
+      const { data: customerData } = await supabase
+        .from('customers')
+        .select('id, name, country, customer_type, vat_number, vat_number_validated')
+        .eq('user_id', user.id)
+        .in('id', customerIds)
+
+      customers = (customerData || []) as ECSalesListCustomer[]
+    }
+
+    // Generate report
+    const report = generateECSalesListReport({
+      invoices,
+      customers,
+      reporterVatNumber,
+      reporterName: company.company_name || '',
+      year,
+      month,
+      quarter,
+    })
+
+    // Generate file content
+    if (format === 'csv') {
+      const content = generateCSV(report)
+      const filename = generateCSVFilename(report)
+
+      return new NextResponse(content, {
+        status: 200,
+        headers: {
+          'Content-Type': 'text/csv; charset=utf-8',
+          'Content-Disposition': `attachment; filename="${filename}"`,
+        },
+      })
+    }
+
+    // XML format
+    const content = generateSKVXml(report)
+    const filename = generateXMLFilename(report)
+
+    return new NextResponse(content, {
+      status: 200,
+      headers: {
+        'Content-Type': 'application/xml; charset=utf-8',
+        'Content-Disposition': `attachment; filename="${filename}"`,
+      },
+    })
+  } catch (err) {
+    console.error('Error generating EC Sales List download:', err)
+    return NextResponse.json(
+      { error: err instanceof Error ? err.message : 'Failed to generate download' },
+      { status: 500 },
+    )
+  }
+}

app/api/extensions/export/eu-sales-list/report/route.ts

@@ -0,0 +1,212 @@
+import { createClient } from '@/lib/supabase/server'
+import { NextResponse } from 'next/server'
+import { fetchAllRows } from '@/lib/supabase/fetch-all'
+import {
+  generateECSalesListReport,
+  getMonthPeriod,
+  getQuarterPeriod,
+  getFilingDeadline,
+  daysUntilDeadline,
+  type ECSalesListInvoice,
+  type ECSalesListCustomer,
+  type GLAccountTotal,
+} from '@/extensions/export/eu-sales-list/lib/eu-sales-list-engine'
+
+/**
+ * GET /api/extensions/export/eu-sales-list/report
+ *
+ * Generate an EC Sales List (periodisk sammanställning) report.
+ *
+ * Query params:
+ *   year     (required) — Fiscal year, e.g. 2026
+ *   month    (optional) — 1-12, for monthly filing (goods)
+ *   quarter  (optional) — 1-4, for quarterly filing (services)
+ *
+ * Either month or quarter must be provided, not both.
+ */
+export async function GET(request: Request) {
+  const supabase = await createClient()
+  const { data: { user } } = await supabase.auth.getUser()
+
+  if (!user) {
+    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+  }
+
+  // Parse query parameters
+  const { searchParams } = new URL(request.url)
+  const yearStr = searchParams.get('year')
+  const monthStr = searchParams.get('month')
+  const quarterStr = searchParams.get('quarter')
+
+  if (!yearStr) {
+    return NextResponse.json({ error: 'year is required' }, { status: 400 })
+  }
+
+  const year = parseInt(yearStr, 10)
+  if (isNaN(year) || year < 2000 || year > 2100) {
+    return NextResponse.json({ error: 'Invalid year. Must be between 2000 and 2100' }, { status: 400 })
+  }
+
+  if (!monthStr && !quarterStr) {
+    return NextResponse.json({ error: 'Either month or quarter is required' }, { status: 400 })
+  }
+
+  if (monthStr && quarterStr) {
+    return NextResponse.json({ error: 'Provide either month or quarter, not both' }, { status: 400 })
+  }
+
+  let month: number | undefined
+  let quarter: number | undefined
+
+  if (monthStr) {
+    month = parseInt(monthStr, 10)
+    if (isNaN(month) || month < 1 || month > 12) {
+      return NextResponse.json({ error: 'Invalid month. Must be 1-12' }, { status: 400 })
+    }
+  }
+
+  if (quarterStr) {
+    quarter = parseInt(quarterStr, 10)
+    if (isNaN(quarter) || quarter < 1 || quarter > 4) {
+      return NextResponse.json({ error: 'Invalid quarter. Must be 1-4' }, { status: 400 })
+    }
+  }
+
+  // Determine date range
+  const period = month !== undefined
+    ? getMonthPeriod(year, month)
+    : getQuarterPeriod(year, quarter!)
+
+  try {
+    // Fetch company settings for reporter info
+    const { data: company, error: companyError } = await supabase
+      .from('company_settings')
+      .select('company_name, org_number, vat_number')
+      .eq('user_id', user.id)
+      .single()
+
+    if (companyError || !company) {
+      return NextResponse.json({ error: 'Company settings not found' }, { status: 404 })
+    }
+
+    const reporterVatNumber = company.vat_number || `SE${(company.org_number || '').replace(/\D/g, '')}01`
+
+    // Fetch invoices for the period
+    const invoices = await fetchAllRows<ECSalesListInvoice>(({ from, to }) =>
+      supabase
+        .from('invoices')
+        .select('id, invoice_number, invoice_date, status, currency, total, total_sek, subtotal, subtotal_sek, vat_treatment, moms_ruta, document_type, credited_invoice_id, customer_id')
+        .eq('user_id', user.id)
+        .gte('invoice_date', period.start)
+        .lte('invoice_date', period.end)
+        .in('status', ['sent', 'paid', 'overdue'])
+        .eq('vat_treatment', 'reverse_charge')
+        .range(from, to)
+    )
+
+    // Collect unique customer IDs
+    const customerIds = [...new Set(invoices.map(inv => inv.customer_id))]
+
+    // Fetch customers (only if we have invoices)
+    let customers: ECSalesListCustomer[] = []
+    if (customerIds.length > 0) {
+      const { data: customerData, error: customerError } = await supabase
+        .from('customers')
+        .select('id, name, country, customer_type, vat_number, vat_number_validated')
+        .eq('user_id', user.id)
+        .in('id', customerIds)
+
+      if (customerError) {
+        return NextResponse.json({ error: 'Failed to fetch customers' }, { status: 500 })
+      }
+
+      customers = (customerData || []) as ECSalesListCustomer[]
+    }
+
+    // Fetch GL account totals for cross-check
+    // Query posted journal entries in the period, then sum credit amounts
+    // on the relevant revenue accounts (3108, 3308, 3109, 3521)
+    const glTotals = await fetchGLTotals(supabase, user.id, period.start, period.end)
+
+    // Generate report
+    const report = generateECSalesListReport({
+      invoices,
+      customers,
+      glTotals: glTotals.length > 0 ? glTotals : undefined,
+      reporterVatNumber,
+      reporterName: company.company_name || '',
+      year,
+      month,
+      quarter,
+    })
+
+    // Add deadline info
+    const deadline = getFilingDeadline(year, month, quarter)
+    const daysLeft = daysUntilDeadline(deadline)
+
+    return NextResponse.json({
+      data: {
+        ...report,
+        deadline,
+        daysUntilDeadline: daysLeft,
+      },
+    })
+  } catch (err) {
+    console.error('Error generating EC Sales List report:', err)
+    return NextResponse.json(
+      { error: err instanceof Error ? err.message : 'Failed to generate report' },
+      { status: 500 },
+    )
+  }
+}
+
+// ── GL cross-check helper ───────────────────────────────────
+
+const CROSS_CHECK_ACCOUNTS = ['3108', '3109', '3308', '3521']
+
+/**
+ * Fetch credit totals for cross-check accounts from posted journal entries.
+ * Mirrors the approach used by /api/bookkeeping/account-totals.
+ */
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+async function fetchGLTotals(supabase: any, userId: string, startDate: string, endDate: string): Promise<GLAccountTotal[]> {
+  // Get posted journal entry IDs in the period
+  const { data: entries, error: entriesError } = await supabase
+    .from('journal_entries')
+    .select('id')
+    .eq('user_id', userId)
+    .eq('status', 'posted')
+    .gte('entry_date', startDate)
+    .lte('entry_date', endDate)
+
+  if (entriesError || !entries || entries.length === 0) return []
+
+  const entryIds = entries.map((e: { id: string }) => e.id)
+
+  // Fetch lines in batches (same pattern as account-totals route)
+  const BATCH_SIZE = 200
+  const allLines: Array<{ account_number: string; credit_amount: number }> = []
+
+  for (let i = 0; i < entryIds.length; i += BATCH_SIZE) {
+    const batch = entryIds.slice(i, i + BATCH_SIZE)
+    const { data: lines } = await supabase
+      .from('journal_entry_lines')
+      .select('account_number, credit_amount')
+      .in('journal_entry_id', batch)
+      .in('account_number', CROSS_CHECK_ACCOUNTS)
+
+    if (lines) allLines.push(...lines)
+  }
+
+  // Aggregate credits per account
+  const totals = new Map<string, number>()
+  for (const line of allLines) {
+    const credit = Number(line.credit_amount) || 0
+    totals.set(line.account_number, (totals.get(line.account_number) ?? 0) + credit)
+  }
+
+  return Array.from(totals.entries()).map(([account_number, credit]) => ({
+    account_number,
+    credit: Math.round(credit * 100) / 100,
+  }))
+}

app/api/extensions/export/intrastat/download/route.ts

@@ -0,0 +1,165 @@
+import { createClient } from '@/lib/supabase/server'
+import { NextResponse } from 'next/server'
+import { fetchAllRows } from '@/lib/supabase/fetch-all'
+import {
+  generateIntrastatReport,
+  type IntrastatInvoice,
+  type IntrastatCustomer,
+  type IntrastatInvoiceItem,
+  type ProductMetadata,
+} from '@/extensions/export/intrastat/lib/intrastat-engine'
+import { generateSCBCsv, generateSCBFilename } from '@/extensions/export/intrastat/lib/scb-csv-generator'
+import { getMonthPeriod } from '@/extensions/export/eu-sales-list/lib/eu-sales-list-engine'
+
+/**
+ * GET /api/extensions/export/intrastat/download
+ *
+ * Download an Intrastat declaration as SCB-compatible CSV.
+ *
+ * Query params:
+ *   year   (required) — Fiscal year
+ *   month  (required) — 1-12
+ */
+export async function GET(request: Request) {
+  const supabase = await createClient()
+  const { data: { user } } = await supabase.auth.getUser()
+
+  if (!user) {
+    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+  }
+
+  const { searchParams } = new URL(request.url)
+  const yearStr = searchParams.get('year')
+  const monthStr = searchParams.get('month')
+
+  if (!yearStr || !monthStr) {
+    return NextResponse.json({ error: 'year and month are required' }, { status: 400 })
+  }
+
+  const year = parseInt(yearStr, 10)
+  const month = parseInt(monthStr, 10)
+
+  if (isNaN(year) || year < 2000 || year > 2100) {
+    return NextResponse.json({ error: 'Invalid year' }, { status: 400 })
+  }
+  if (isNaN(month) || month < 1 || month > 12) {
+    return NextResponse.json({ error: 'Invalid month' }, { status: 400 })
+  }
+
+  const period = getMonthPeriod(year, month)
+
+  try {
+    const { data: company } = await supabase
+      .from('company_settings')
+      .select('company_name, org_number, vat_number')
+      .eq('user_id', user.id)
+      .single()
+
+    if (!company) {
+      return NextResponse.json({ error: 'Company settings not found' }, { status: 404 })
+    }
+
+    const reporterVatNumber = company.vat_number || `SE${(company.org_number || '').replace(/\D/g, '')}01`
+
+    // Fetch invoices
+    const invoices = await fetchAllRows<IntrastatInvoice>(({ from, to }) =>
+      supabase
+        .from('invoices')
+        .select('id, invoice_number, invoice_date, status, vat_treatment, moms_ruta, currency, total_sek, subtotal_sek, subtotal, document_type, credited_invoice_id, customer_id')
+        .eq('user_id', user.id)
+        .gte('invoice_date', period.start)
+        .lte('invoice_date', period.end)
+        .in('status', ['sent', 'paid', 'overdue'])
+        .eq('vat_treatment', 'reverse_charge')
+        .range(from, to)
+    )
+
+    // Fetch invoice items
+    const invoiceIds = invoices.map(inv => inv.id)
+    let invoiceItems: IntrastatInvoiceItem[] = []
+    if (invoiceIds.length > 0) {
+      const BATCH_SIZE = 200
+      for (let i = 0; i < invoiceIds.length; i += BATCH_SIZE) {
+        const batch = invoiceIds.slice(i, i + BATCH_SIZE)
+        const { data: items } = await supabase
+          .from('invoice_items')
+          .select('id, invoice_id, description, quantity, unit_price, total, total_sek')
+          .in('invoice_id', batch)
+
+        if (items) invoiceItems.push(...(items as IntrastatInvoiceItem[]))
+      }
+    }
+
+    // Fetch customers
+    const customerIds = [...new Set(invoices.map(inv => inv.customer_id))]
+    let customers: IntrastatCustomer[] = []
+    if (customerIds.length > 0) {
+      const { data: customerData } = await supabase
+        .from('customers')
+        .select('id, name, country, vat_number')
+        .eq('user_id', user.id)
+        .in('id', customerIds)
+
+      customers = (customerData || []) as IntrastatCustomer[]
+    }
+
+    // Fetch product metadata
+    const { data: productData } = await supabase
+      .from('extension_data')
+      .select('key, value')
+      .eq('user_id', user.id)
+      .eq('extension_id', 'export/intrastat')
+      .ilike('key', 'product:%')
+
+    const products: ProductMetadata[] = (productData || []).map((d: { key: string; value: Record<string, unknown> }) => ({
+      productId: d.key.replace('product:', ''),
+      cnCode: (d.value.cn_code as string) || null,
+      description: (d.value.description as string) || '',
+      netWeightKg: d.value.net_weight_kg !== undefined ? Number(d.value.net_weight_kg) : null,
+      countryOfOrigin: (d.value.country_of_origin as string) || 'SE',
+      supplementaryUnit: d.value.supplementary_unit !== undefined ? Number(d.value.supplementary_unit) : null,
+      supplementaryUnitType: (d.value.supplementary_unit_type as string) || null,
+    }))
+
+    // Fetch settings
+    const { data: settingsData } = await supabase
+      .from('extension_data')
+      .select('value')
+      .eq('user_id', user.id)
+      .eq('extension_id', 'export/intrastat')
+      .eq('key', 'settings')
+      .maybeSingle()
+
+    const settings = settingsData?.value as Record<string, unknown> | undefined
+
+    const report = generateIntrastatReport({
+      invoices,
+      invoiceItems,
+      customers,
+      products,
+      reporterVatNumber,
+      reporterName: company.company_name || '',
+      year,
+      month,
+      defaultTransactionNature: (settings?.default_transaction_nature as string) || '11',
+      defaultDeliveryTerms: (settings?.default_delivery_terms as string) || 'FCA',
+    })
+
+    const content = generateSCBCsv(report)
+    const filename = generateSCBFilename(report)
+
+    return new NextResponse(content, {
+      status: 200,
+      headers: {
+        'Content-Type': 'text/csv; charset=utf-8',
+        'Content-Disposition': `attachment; filename="${filename}"`,
+      },
+    })
+  } catch (err) {
+    console.error('Error generating Intrastat download:', err)
+    return NextResponse.json(
+      { error: err instanceof Error ? err.message : 'Failed to generate download' },
+      { status: 500 },
+    )
+  }
+}

app/api/extensions/export/intrastat/report/route.ts

@@ -0,0 +1,214 @@
+import { createClient } from '@/lib/supabase/server'
+import { NextResponse } from 'next/server'
+import { fetchAllRows } from '@/lib/supabase/fetch-all'
+import {
+  generateIntrastatReport,
+  type IntrastatInvoice,
+  type IntrastatCustomer,
+  type IntrastatInvoiceItem,
+  type ProductMetadata,
+} from '@/extensions/export/intrastat/lib/intrastat-engine'
+import { getMonthPeriod } from '@/extensions/export/eu-sales-list/lib/eu-sales-list-engine'
+
+/**
+ * GET /api/extensions/export/intrastat/report
+ *
+ * Generate an Intrastat declaration report for the specified month.
+ *
+ * Query params:
+ *   year   (required) — Fiscal year
+ *   month  (required) — 1-12 (Intrastat is always monthly)
+ */
+export async function GET(request: Request) {
+  const supabase = await createClient()
+  const { data: { user } } = await supabase.auth.getUser()
+
+  if (!user) {
+    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+  }
+
+  const { searchParams } = new URL(request.url)
+  const yearStr = searchParams.get('year')
+  const monthStr = searchParams.get('month')
+
+  if (!yearStr || !monthStr) {
+    return NextResponse.json({ error: 'year and month are required' }, { status: 400 })
+  }
+
+  const year = parseInt(yearStr, 10)
+  const month = parseInt(monthStr, 10)
+
+  if (isNaN(year) || year < 2000 || year > 2100) {
+    return NextResponse.json({ error: 'Invalid year' }, { status: 400 })
+  }
+  if (isNaN(month) || month < 1 || month > 12) {
+    return NextResponse.json({ error: 'Invalid month' }, { status: 400 })
+  }
+
+  const period = getMonthPeriod(year, month)
+
+  try {
+    // Fetch company settings
+    const { data: company } = await supabase
+      .from('company_settings')
+      .select('company_name, org_number, vat_number')
+      .eq('user_id', user.id)
+      .single()
+
+    if (!company) {
+      return NextResponse.json({ error: 'Company settings not found' }, { status: 404 })
+    }
+
+    const reporterVatNumber = company.vat_number || `SE${(company.org_number || '').replace(/\D/g, '')}01`
+
+    // Fetch reverse-charge invoices for the period
+    const invoices = await fetchAllRows<IntrastatInvoice>(({ from, to }) =>
+      supabase
+        .from('invoices')
+        .select('id, invoice_number, invoice_date, status, vat_treatment, moms_ruta, currency, total_sek, subtotal_sek, subtotal, document_type, credited_invoice_id, customer_id')
+        .eq('user_id', user.id)
+        .gte('invoice_date', period.start)
+        .lte('invoice_date', period.end)
+        .in('status', ['sent', 'paid', 'overdue'])
+        .eq('vat_treatment', 'reverse_charge')
+        .range(from, to)
+    )
+
+    // Fetch invoice items for those invoices
+    const invoiceIds = invoices.map(inv => inv.id)
+    let invoiceItems: IntrastatInvoiceItem[] = []
+    if (invoiceIds.length > 0) {
+      const BATCH_SIZE = 200
+      for (let i = 0; i < invoiceIds.length; i += BATCH_SIZE) {
+        const batch = invoiceIds.slice(i, i + BATCH_SIZE)
+        const { data: items } = await supabase
+          .from('invoice_items')
+          .select('id, invoice_id, description, quantity, unit_price, total, total_sek')
+          .in('invoice_id', batch)
+
+        if (items) invoiceItems.push(...(items as IntrastatInvoiceItem[]))
+      }
+    }
+
+    // Fetch customers
+    const customerIds = [...new Set(invoices.map(inv => inv.customer_id))]
+    let customers: IntrastatCustomer[] = []
+    if (customerIds.length > 0) {
+      const { data: customerData } = await supabase
+        .from('customers')
+        .select('id, name, country, vat_number')
+        .eq('user_id', user.id)
+        .in('id', customerIds)
+
+      customers = (customerData || []) as IntrastatCustomer[]
+    }
+
+    // Fetch product metadata from extension_data
+    const { data: productData } = await supabase
+      .from('extension_data')
+      .select('key, value')
+      .eq('user_id', user.id)
+      .eq('extension_id', 'export/intrastat')
+      .ilike('key', 'product:%')
+
+    const products: ProductMetadata[] = (productData || []).map((d: { key: string; value: Record<string, unknown> }) => ({
+      productId: d.key.replace('product:', ''),
+      cnCode: (d.value.cn_code as string) || null,
+      description: (d.value.description as string) || '',
+      netWeightKg: d.value.net_weight_kg !== undefined ? Number(d.value.net_weight_kg) : null,
+      countryOfOrigin: (d.value.country_of_origin as string) || 'SE',
+      supplementaryUnit: d.value.supplementary_unit !== undefined ? Number(d.value.supplementary_unit) : null,
+      supplementaryUnitType: (d.value.supplementary_unit_type as string) || null,
+    }))
+
+    // Fetch extension settings
+    const { data: settingsData } = await supabase
+      .from('extension_data')
+      .select('value')
+      .eq('user_id', user.id)
+      .eq('extension_id', 'export/intrastat')
+      .eq('key', 'settings')
+      .maybeSingle()
+
+    const settings = settingsData?.value as Record<string, unknown> | undefined
+    const defaultTransactionNature = (settings?.default_transaction_nature as string) || '11'
+    const defaultDeliveryTerms = (settings?.default_delivery_terms as string) || 'FCA'
+
+    // Calculate prior cumulative value (rolling 12 months excluding current)
+    const priorCumulativeValue = await calculatePriorCumulative(supabase, user.id, year, month)
+
+    const report = generateIntrastatReport({
+      invoices,
+      invoiceItems,
+      customers,
+      products,
+      reporterVatNumber,
+      reporterName: company.company_name || '',
+      year,
+      month,
+      defaultTransactionNature,
+      defaultDeliveryTerms,
+      priorCumulativeValue,
+    })
+
+    return NextResponse.json({ data: report })
+  } catch (err) {
+    console.error('Error generating Intrastat report:', err)
+    return NextResponse.json(
+      { error: err instanceof Error ? err.message : 'Failed to generate report' },
+      { status: 500 },
+    )
+  }
+}
+
+/**
+ * Calculate the cumulative dispatch value for the 11 months prior to the
+ * current period (rolling 12-month window for threshold monitoring).
+ */
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+async function calculatePriorCumulative(supabase: any, userId: string, year: number, month: number): Promise<number> {
+  // Calculate 11-month lookback window
+  let startMonth = month - 11
+  let startYear = year
+  while (startMonth < 1) {
+    startMonth += 12
+    startYear--
+  }
+  const startDate = `${startYear}-${String(startMonth).padStart(2, '0')}-01`
+
+  // End date is the day before the current period
+  let prevMonth = month - 1
+  let prevYear = year
+  if (prevMonth < 1) {
+    prevMonth = 12
+    prevYear--
+  }
+  const lastDay = new Date(prevYear, prevMonth, 0).getDate()
+  const endDate = `${prevYear}-${String(prevMonth).padStart(2, '0')}-${String(lastDay).padStart(2, '0')}`
+
+  if (startDate > endDate) return 0
+
+  // Sum total_sek for reverse_charge invoices to EU in the lookback window
+  const { data, error } = await supabase
+    .from('invoices')
+    .select('total_sek, subtotal_sek, subtotal')
+    .eq('user_id', userId)
+    .gte('invoice_date', startDate)
+    .lte('invoice_date', endDate)
+    .in('status', ['sent', 'paid', 'overdue'])
+    .eq('vat_treatment', 'reverse_charge')
+    .eq('moms_ruta', '35')
+
+  if (error || !data) return 0
+
+  let total = 0
+  for (const inv of data) {
+    if (inv.subtotal_sek !== null) {
+      total += Number(inv.subtotal_sek) || 0
+    } else {
+      total += Number(inv.subtotal) || 0
+    }
+  }
+
+  return Math.round(total * 100) / 100
+}

app/api/extensions/export/vat-monitor/report/route.ts

@@ -0,0 +1,188 @@
+import { createClient } from '@/lib/supabase/server'
+import { NextResponse } from 'next/server'
+import { fetchAllRows } from '@/lib/supabase/fetch-all'
+import {
+  generateVatMonitorReport,
+  VAT_MONITOR_ACCOUNTS,
+  type GLLine,
+  type VatMonitorInvoice,
+  type VatMonitorCustomer,
+} from '@/extensions/export/vat-monitor/lib/vat-monitor-engine'
+import {
+  getMonthPeriod,
+  getQuarterPeriod,
+} from '@/extensions/export/eu-sales-list/lib/eu-sales-list-engine'
+
+/**
+ * GET /api/extensions/export/vat-monitor/report
+ *
+ * Generate a VAT Monitor report for the specified period.
+ *
+ * Query params:
+ *   year      (required) — Fiscal year
+ *   month     (optional) — 1-12
+ *   quarter   (optional) — 1-4
+ *   compare   (optional) — 'previous' to include period comparison
+ */
+export async function GET(request: Request) {
+  const supabase = await createClient()
+  const { data: { user } } = await supabase.auth.getUser()
+
+  if (!user) {
+    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+  }
+
+  const { searchParams } = new URL(request.url)
+  const yearStr = searchParams.get('year')
+  const monthStr = searchParams.get('month')
+  const quarterStr = searchParams.get('quarter')
+  const compare = searchParams.get('compare')
+
+  if (!yearStr) {
+    return NextResponse.json({ error: 'year is required' }, { status: 400 })
+  }
+
+  const year = parseInt(yearStr, 10)
+  if (isNaN(year) || year < 2000 || year > 2100) {
+    return NextResponse.json({ error: 'Invalid year' }, { status: 400 })
+  }
+
+  if (!monthStr && !quarterStr) {
+    return NextResponse.json({ error: 'Either month or quarter is required' }, { status: 400 })
+  }
+
+  if (monthStr && quarterStr) {
+    return NextResponse.json({ error: 'Provide either month or quarter, not both' }, { status: 400 })
+  }
+
+  let month: number | undefined
+  let quarter: number | undefined
+
+  if (monthStr) {
+    month = parseInt(monthStr, 10)
+    if (isNaN(month) || month < 1 || month > 12) {
+      return NextResponse.json({ error: 'Invalid month' }, { status: 400 })
+    }
+  }
+
+  if (quarterStr) {
+    quarter = parseInt(quarterStr, 10)
+    if (isNaN(quarter) || quarter < 1 || quarter > 4) {
+      return NextResponse.json({ error: 'Invalid quarter' }, { status: 400 })
+    }
+  }
+
+  const period = month !== undefined
+    ? getMonthPeriod(year, month)
+    : getQuarterPeriod(year, quarter!)
+
+  try {
+    // Fetch GL lines for current period
+    const glLines = await fetchGLLines(supabase, user.id, period.start, period.end)
+
+    // Fetch invoices for validation
+    const invoices = await fetchAllRows<VatMonitorInvoice>(({ from, to }) =>
+      supabase
+        .from('invoices')
+        .select('id, invoice_number, vat_treatment, moms_ruta, customer_id')
+        .eq('user_id', user.id)
+        .gte('invoice_date', period.start)
+        .lte('invoice_date', period.end)
+        .in('status', ['sent', 'paid', 'overdue'])
+        .range(from, to)
+    )
+
+    // Fetch customers for those invoices
+    const customerIds = [...new Set(invoices.map(inv => inv.customer_id))]
+    let customers: VatMonitorCustomer[] = []
+    if (customerIds.length > 0) {
+      const { data: customerData } = await supabase
+        .from('customers')
+        .select('id, name, country, vat_number, vat_number_validated')
+        .eq('user_id', user.id)
+        .in('id', customerIds)
+
+      customers = (customerData || []) as VatMonitorCustomer[]
+    }
+
+    // Fetch previous period GL lines for comparison
+    let previousGlLines: GLLine[] | undefined
+    if (compare === 'previous') {
+      const prevPeriod = getPreviousPeriod(year, month, quarter)
+      previousGlLines = await fetchGLLines(supabase, user.id, prevPeriod.start, prevPeriod.end)
+    }
+
+    const report = generateVatMonitorReport({
+      glLines,
+      invoices,
+      customers,
+      year,
+      month,
+      quarter,
+      previousGlLines,
+    })
+
+    return NextResponse.json({ data: report })
+  } catch (err) {
+    console.error('Error generating VAT Monitor report:', err)
+    return NextResponse.json(
+      { error: err instanceof Error ? err.message : 'Failed to generate report' },
+      { status: 500 },
+    )
+  }
+}
+
+// ── Helpers ─────────────────────────────────────────────────
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+async function fetchGLLines(supabase: any, userId: string, startDate: string, endDate: string): Promise<GLLine[]> {
+  // Fetch posted journal entry IDs for the period
+  const { data: entries, error: entriesError } = await supabase
+    .from('journal_entries')
+    .select('id')
+    .eq('user_id', userId)
+    .eq('status', 'posted')
+    .gte('entry_date', startDate)
+    .lte('entry_date', endDate)
+
+  if (entriesError || !entries || entries.length === 0) return []
+
+  const entryIds = entries.map((e: { id: string }) => e.id)
+
+  // Fetch lines in batches
+  const BATCH_SIZE = 200
+  const allLines: GLLine[] = []
+
+  for (let i = 0; i < entryIds.length; i += BATCH_SIZE) {
+    const batch = entryIds.slice(i, i + BATCH_SIZE)
+    const { data: lines } = await supabase
+      .from('journal_entry_lines')
+      .select('account_number, debit_amount, credit_amount')
+      .in('journal_entry_id', batch)
+      .in('account_number', VAT_MONITOR_ACCOUNTS)
+
+    if (lines) allLines.push(...lines)
+  }
+
+  return allLines
+}
+
+function getPreviousPeriod(year: number, month?: number, quarter?: number): { start: string; end: string } {
+  if (month !== undefined) {
+    let prevMonth = month - 1
+    let prevYear = year
+    if (prevMonth < 1) {
+      prevMonth = 12
+      prevYear--
+    }
+    return getMonthPeriod(prevYear, prevMonth)
+  }
+
+  let prevQuarter = quarter! - 1
+  let prevYear = year
+  if (prevQuarter < 1) {
+    prevQuarter = 4
+    prevYear--
+  }
+  return getQuarterPeriod(prevYear, prevQuarter)
+}

app/api/vat/validate/__tests__/route.test.ts

@@ -0,0 +1,220 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { createQueuedMockSupabase, createMockRequest, parseJsonResponse } from '@/tests/helpers'
+
+// Mock Supabase
+vi.mock('@/lib/supabase/server', () => ({
+  createClient: vi.fn(),
+}))
+
+// Mock VIES client
+const mockValidateVatNumber = vi.fn()
+vi.mock('@/lib/vat/vies-client', () => ({
+  validateVatNumber: (...args: unknown[]) => mockValidateVatNumber(...args),
+}))
+
+import { createClient } from '@/lib/supabase/server'
+import { POST } from '../route'
+
+const mockCreateClient = vi.mocked(createClient)
+
+describe('POST /api/vat/validate', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+  })
+
+  it('returns 401 when not authenticated', async () => {
+    const { supabase } = createQueuedMockSupabase()
+    supabase.auth.getUser.mockResolvedValue({
+      data: { user: null },
+      error: { message: 'Not authenticated' },
+    })
+    mockCreateClient.mockResolvedValue(supabase as never)
+
+    const req = createMockRequest('/api/vat/validate', {
+      method: 'POST',
+      body: { vat_number: 'DE123456789' },
+    })
+
+    const res = await POST(req)
+    const { status, body } = await parseJsonResponse(res)
+
+    expect(status).toBe(401)
+    expect(body).toEqual({ error: 'Unauthorized' })
+  })
+
+  it('returns 400 when vat_number is missing', async () => {
+    const { supabase } = createQueuedMockSupabase()
+    supabase.auth.getUser.mockResolvedValue({
+      data: { user: { id: 'user-1' } },
+      error: null,
+    })
+    mockCreateClient.mockResolvedValue(supabase as never)
+
+    const req = createMockRequest('/api/vat/validate', {
+      method: 'POST',
+      body: {},
+    })
+
+    const res = await POST(req)
+    const { status } = await parseJsonResponse(res)
+
+    expect(status).toBe(400)
+  })
+
+  it('returns 400 when vat_number is too short', async () => {
+    const { supabase } = createQueuedMockSupabase()
+    supabase.auth.getUser.mockResolvedValue({
+      data: { user: { id: 'user-1' } },
+      error: null,
+    })
+    mockCreateClient.mockResolvedValue(supabase as never)
+
+    const req = createMockRequest('/api/vat/validate', {
+      method: 'POST',
+      body: { vat_number: 'DE' },
+    })
+
+    const res = await POST(req)
+    const { status } = await parseJsonResponse(res)
+
+    expect(status).toBe(400)
+  })
+
+  it('returns valid result from VIES', async () => {
+    const { supabase } = createQueuedMockSupabase()
+    supabase.auth.getUser.mockResolvedValue({
+      data: { user: { id: 'user-1' } },
+      error: null,
+    })
+    mockCreateClient.mockResolvedValue(supabase as never)
+    mockValidateVatNumber.mockResolvedValueOnce({
+      valid: true,
+      name: 'Test GmbH',
+      address: 'Berlin',
+      country_code: 'DE',
+      vat_number: 'DE123456789',
+    })
+
+    const req = createMockRequest('/api/vat/validate', {
+      method: 'POST',
+      body: { vat_number: 'DE123456789' },
+    })
+
+    const res = await POST(req)
+    const { status, body } = await parseJsonResponse(res)
+
+    expect(status).toBe(200)
+    expect(body).toEqual({
+      valid: true,
+      name: 'Test GmbH',
+      address: 'Berlin',
+      country_code: 'DE',
+      vat_number: 'DE123456789',
+    })
+  })
+
+  it('returns invalid result from VIES', async () => {
+    const { supabase } = createQueuedMockSupabase()
+    supabase.auth.getUser.mockResolvedValue({
+      data: { user: { id: 'user-1' } },
+      error: null,
+    })
+    mockCreateClient.mockResolvedValue(supabase as never)
+    mockValidateVatNumber.mockResolvedValueOnce({
+      valid: false,
+      country_code: 'DE',
+      vat_number: 'DE000000000',
+    })
+
+    const req = createMockRequest('/api/vat/validate', {
+      method: 'POST',
+      body: { vat_number: 'DE000000000' },
+    })
+
+    const res = await POST(req)
+    const { status, body } = await parseJsonResponse(res)
+
+    expect(status).toBe(200)
+    expect(body).toMatchObject({ valid: false })
+  })
+
+  it('updates customer when customer_id provided and valid', async () => {
+    const { supabase } = createQueuedMockSupabase()
+    supabase.auth.getUser.mockResolvedValue({
+      data: { user: { id: 'user-1' } },
+      error: null,
+    })
+    mockCreateClient.mockResolvedValue(supabase as never)
+    mockValidateVatNumber.mockResolvedValueOnce({
+      valid: true,
+      name: 'Test GmbH',
+      country_code: 'DE',
+      vat_number: 'DE123456789',
+    })
+
+    const req = createMockRequest('/api/vat/validate', {
+      method: 'POST',
+      body: {
+        vat_number: 'DE123456789',
+        customer_id: '550e8400-e29b-41d4-a716-446655440000',
+      },
+    })
+
+    const res = await POST(req)
+    const { status, body } = await parseJsonResponse(res)
+
+    expect(status).toBe(200)
+    expect(body).toMatchObject({ valid: true })
+  })
+
+  it('does not update customer when validation fails', async () => {
+    const { supabase } = createQueuedMockSupabase()
+    supabase.auth.getUser.mockResolvedValue({
+      data: { user: { id: 'user-1' } },
+      error: null,
+    })
+    mockCreateClient.mockResolvedValue(supabase as never)
+    mockValidateVatNumber.mockResolvedValueOnce({
+      valid: false,
+      error: 'Invalid VAT number format',
+    })
+
+    const req = createMockRequest('/api/vat/validate', {
+      method: 'POST',
+      body: {
+        vat_number: 'DE12345',
+        customer_id: '550e8400-e29b-41d4-a716-446655440000',
+      },
+    })
+
+    const res = await POST(req)
+    const { status, body } = await parseJsonResponse(res)
+
+    expect(status).toBe(200)
+    expect(body).toMatchObject({ valid: false })
+  })
+
+  it('handles VIES service error gracefully', async () => {
+    const { supabase } = createQueuedMockSupabase()
+    supabase.auth.getUser.mockResolvedValue({
+      data: { user: { id: 'user-1' } },
+      error: null,
+    })
+    mockCreateClient.mockResolvedValue(supabase as never)
+    mockValidateVatNumber.mockResolvedValueOnce({
+      valid: false,
+      error: 'Could not verify VAT number. Service temporarily unavailable.',
+    })
+
+    const req = createMockRequest('/api/vat/validate', {
+      method: 'POST',
+      body: { vat_number: 'DE123456789' },
+    })
+
+    const res = await POST(req)
+    const { status, body } = await parseJsonResponse(res)
+
+    expect(status).toBe(200)
+    expect(body).toMatchObject({ valid: false, error: expect.stringContaining('unavailable') })
+  })
+})

app/api/vat/validate/route.ts

@@ -1,12 +1,9 @@
 import { createClient } from '@/lib/supabase/server'
 import { NextResponse } from 'next/server'
+import { validateBody } from '@/lib/api/validate'
+import { ValidateVatNumberSchema } from '@/lib/api/schemas'
+import { validateVatNumber } from '@/lib/vat/vies-client'
 
-/**
- * Validate EU VAT number using VIES (VAT Information Exchange System)
- *
- * The EU provides a SOAP-based API, but we'll use a REST wrapper
- * In production, you might want to use the official SOAP API or a dedicated service
- */
 export async function POST(request: Request) {
   const supabase = await createClient()
 
@@ -16,113 +13,24 @@ export async function POST(request: Request) {
     return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
   }
 
-  const { vat_number, customer_id } = await request.json()
+  const result = await validateBody(request, ValidateVatNumberSchema)
+  if (!result.success) return result.response
+  const { vat_number, customer_id } = result.data
 
-  if (!vat_number) {
-    return NextResponse.json({ error: 'VAT number is required' }, { status: 400 })
-  }
+  const validation = await validateVatNumber(vat_number)
 
-  // Extract country code and number
-  const countryCode = vat_number.substring(0, 2).toUpperCase()
-  const vatNumber = vat_number.substring(2).replace(/\s/g, '')
-
-  try {
-    // Use the EU VIES validation API
-    // Note: In production, you should use the official SOAP API or a reliable service
-    const response = await fetch(
-      `https://ec.europa.eu/taxation_customs/vies/rest-api/ms/${countryCode}/vat/${vatNumber}`,
-      {
-        method: 'GET',
-        headers: {
-          Accept: 'application/json',
-        },
-      }
-    )
-
-    if (!response.ok) {
-      // If VIES is unavailable, return a soft error
-      return NextResponse.json({
-        valid: false,
-        error: 'VAT validation service unavailable. Please try again later.',
+  // Update customer record if customer_id provided and VAT is valid
+  if (customer_id && validation.valid) {
+    await supabase
+      .from('customers')
+      .update({
+        vat_number: validation.vat_number,
+        vat_number_validated: true,
+        vat_number_validated_at: new Date().toISOString(),
       })
-    }
-
-    const data = await response.json()
-
-    const isValid = data.isValid === true
-
-    // Update customer if customer_id provided
-    if (customer_id && isValid) {
-      await supabase
-        .from('customers')
-        .update({
-          vat_number: vat_number.toUpperCase(),
-          vat_number_validated: true,
-          vat_number_validated_at: new Date().toISOString(),
-        })
-        .eq('id', customer_id)
-        .eq('user_id', user.id)
-    }
-
-    return NextResponse.json({
-      valid: isValid,
-      name: data.name || null,
-      address: data.address || null,
-      country_code: countryCode,
-      vat_number: vat_number.toUpperCase(),
-    })
-  } catch (error) {
-    console.error('VAT validation error:', error)
-
-    // Fallback: basic format validation
-    const isValidFormat = validateVatNumberFormat(countryCode, vatNumber)
-
-    return NextResponse.json({
-      valid: false,
-      error: 'Could not verify VAT number. Service temporarily unavailable.',
-      format_valid: isValidFormat,
-    })
+      .eq('id', customer_id)
+      .eq('user_id', user.id)
   }
-}
-
-/**
- * Basic VAT number format validation by country
- */
-function validateVatNumberFormat(countryCode: string, vatNumber: string): boolean {
-  const patterns: Record<string, RegExp> = {
-    AT: /^U\d{8}$/,
-    BE: /^0\d{9}$/,
-    BG: /^\d{9,10}$/,
-    CY: /^\d{8}[A-Z]$/,
-    CZ: /^\d{8,10}$/,
-    DE: /^\d{9}$/,
-    DK: /^\d{8}$/,
-    EE: /^\d{9}$/,
-    EL: /^\d{9}$/, // Greece
-    ES: /^[A-Z0-9]\d{7}[A-Z0-9]$/,
-    FI: /^\d{8}$/,
-    FR: /^[A-Z0-9]{2}\d{9}$/,
-    HR: /^\d{11}$/,
-    HU: /^\d{8}$/,
-    IE: /^[0-9A-Z]{8,9}$/,
-    IT: /^\d{11}$/,
-    LT: /^\d{9,12}$/,
-    LU: /^\d{8}$/,
-    LV: /^\d{11}$/,
-    MT: /^\d{8}$/,
-    NL: /^\d{9}B\d{2}$/,
-    PL: /^\d{10}$/,
-    PT: /^\d{9}$/,
-    RO: /^\d{2,10}$/,
-    SE: /^\d{12}$/,
-    SI: /^\d{8}$/,
-    SK: /^\d{10}$/,
-  }
-
-  const pattern = patterns[countryCode]
-  if (!pattern) {
-    return false
-  }
-
-  return pattern.test(vatNumber)
+
+  return NextResponse.json(validation)
 }

components/dashboard/DashboardNav.tsx

@@ -1,6 +1,6 @@
 'use client'
 
-import { useState, useCallback } from 'react'
+import { useState, useCallback, useEffect } from 'react'
 import Link from 'next/link'
 import { usePathname, useRouter } from 'next/navigation'
 import { createClient } from '@/lib/supabase/client'
@@ -74,7 +74,13 @@ export default function DashboardNav({ companyName, entityType, enabledExtension
   const isOnOvrigtPage = ['/import', '/help', '/settings'].some(p => pathname.startsWith(p))
   const [manualOvrigtExpanded, setManualOvrigtExpanded] = useState(false)
   const isOvrigtExpanded = isOnOvrigtPage || manualOvrigtExpanded
-  const [isTillaggExpanded, setIsTillaggExpanded] = useState(false)
+  // Auto-expand Tillägg when on an extension page, or when manually toggled (persisted)
+  const isOnExtensionPage = pathname.startsWith('/e/')
+  const [manualTillaggExpanded, setManualTillaggExpanded] = useState(() => {
+    if (typeof window === 'undefined') return false
+    return localStorage.getItem('tillagg-expanded') === 'true'
+  })
+  const isTillaggExpanded = isOnExtensionPage || manualTillaggExpanded
   const [liveExtensions, setLiveExtensions] = useState(enabledExtensions ?? [])
 
   const fetchExtensions = useCallback(async () => {
@@ -89,9 +95,16 @@ export default function DashboardNav({ companyName, entityType, enabledExtension
     }
   }, [])
 
+  // Fetch extensions on mount if Tillägg starts expanded
+  useEffect(() => {
+    if (isTillaggExpanded) fetchExtensions()
+  // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [])
+
   const toggleTillagg = () => {
     const next = !isTillaggExpanded
-    setIsTillaggExpanded(next)
+    setManualTillaggExpanded(next)
+    localStorage.setItem('tillagg-expanded', String(next))
     if (next) fetchExtensions()
   }
 

components/extensions/SectorCard.tsx

@@ -7,8 +7,8 @@ export default function SectorCard({ sector }: { sector: Sector }) {
   const Icon = resolveIcon(sector.icon)
 
   return (
-    <Link href={`/extensions/${sector.slug}`}>
-      <Card className="group hover:border-primary/30 transition-colors cursor-pointer">
+    <Link href={`/extensions/${sector.slug}`} className="h-full">
+      <Card className="group hover:border-primary/30 transition-colors cursor-pointer h-full">
         <CardContent className="pt-6">
           <div className="flex items-start gap-3">
             <div className="flex h-10 w-10 items-center justify-center rounded-lg bg-primary/10 flex-shrink-0">
@@ -18,7 +18,7 @@ export default function SectorCard({ sector }: { sector: Sector }) {
               <h3 className="text-sm font-medium group-hover:text-primary transition-colors">
                 {sector.name}
               </h3>
-              <p className="text-xs text-muted-foreground mt-0.5">{sector.description}</p>
+              <p className="text-xs text-muted-foreground mt-0.5 line-clamp-2">{sector.description}</p>
               <p className="text-xs text-muted-foreground mt-1.5">
                 {sector.extensions.length} tillägg
               </p>

components/extensions/export/CurrencyReceivablesWorkspace.tsx

@@ -0,0 +1,715 @@
+'use client'
+
+import { useState, useEffect, useCallback } from 'react'
+import type { WorkspaceComponentProps } from '@/lib/extensions/workspace-registry'
+import { useMockData } from '@/lib/extensions/use-mock-data'
+import ExtensionLoadingSkeleton from '@/components/extensions/shared/ExtensionLoadingSkeleton'
+import MockDataBanner from '@/components/extensions/shared/MockDataBanner'
+import MockDataImportDialog from '@/components/extensions/shared/MockDataImportDialog'
+import type { CsvFieldDef } from '@/components/extensions/shared/MockDataImportDialog'
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card'
+import { Badge } from '@/components/ui/badge'
+import {
+  Select, SelectContent, SelectItem, SelectTrigger, SelectValue,
+} from '@/components/ui/select'
+import {
+  Table, TableBody, TableCell, TableHead, TableHeader, TableRow,
+} from '@/components/ui/table'
+import {
+  TrendingUp, TrendingDown, RefreshCw, Info, ArrowUpDown, FlaskConical,
+} from 'lucide-react'
+import { Button } from '@/components/ui/button'
+import { cn } from '@/lib/utils'
+
+// ── Types ─────────────────────────────────────────────────────
+
+interface CurrencyExposure {
+  currency: string
+  totalForeignAmount: number
+  bookedSekValue: number
+  currentSekValue: number
+  unrealizedGainLoss: number
+  invoiceCount: number
+  averageBookedRate: number
+  currentRate: number
+}
+
+interface ForeignReceivable {
+  invoiceId: string
+  invoiceNumber: string
+  customerName: string
+  customerCountry: string
+  currency: string
+  foreignAmount: number
+  bookedSekAmount: number
+  bookedRate: number
+  currentSekAmount: number
+  currentRate: number
+  unrealizedGainLoss: number
+  invoiceDate: string
+  dueDate: string
+  daysOutstanding: number
+}
+
+interface MonthlyFXTrend {
+  month: string
+  realizedGains: number
+  realizedLosses: number
+  netRealized: number
+}
+
+interface ExchangeRateInfo {
+  currency: string
+  rate: number
+  date: string
+}
+
+interface RevalPreview {
+  totalUnrealizedGainLoss: number
+  gains: number
+  losses: number
+}
+
+interface ReportData {
+  referenceDate: string
+  exchangeRates: ExchangeRateInfo[]
+  exposureByCurrency: CurrencyExposure[]
+  receivables: ForeignReceivable[]
+  realizedGainLoss: {
+    year: number
+    gains: number
+    losses: number
+    net: number
+  }
+  monthlyTrend: MonthlyFXTrend[]
+  revalPreview: RevalPreview
+  totals: {
+    bookedSekValue: number
+    currentSekValue: number
+    totalUnrealizedGainLoss: number
+    receivableCount: number
+    currencyCount: number
+  }
+}
+
+// ── Helpers ───────────────────────────────────────────────────
+
+function formatSEK(amount: number): string {
+  return Math.round(amount).toLocaleString('sv-SE')
+}
+
+function formatAmount(amount: number, decimals = 2): string {
+  return amount.toLocaleString('sv-SE', {
+    minimumFractionDigits: decimals,
+    maximumFractionDigits: decimals,
+  })
+}
+
+const CURRENCY_SYMBOLS: Record<string, string> = {
+  EUR: '€', USD: '$', GBP: '£', NOK: 'kr', DKK: 'kr', SEK: 'kr',
+}
+
+function currencySymbol(code: string): string {
+  return CURRENCY_SYMBOLS[code] || code
+}
+
+const MONTH_NAMES = [
+  'Jan', 'Feb', 'Mar', 'Apr', 'Maj', 'Jun',
+  'Jul', 'Aug', 'Sep', 'Okt', 'Nov', 'Dec',
+]
+
+function monthLabel(monthKey: string): string {
+  const m = parseInt(monthKey.split('-')[1], 10)
+  return MONTH_NAMES[m - 1] || monthKey
+}
+
+function currentYear(): number { return new Date().getFullYear() }
+
+type SortField = 'unrealizedGainLoss' | 'foreignAmount' | 'daysOutstanding' | 'customerName'
+type SortDir = 'asc' | 'desc'
+
+// ── Mock Data Config ──────────────────────────────────────────
+
+const MOCK_CSV_FIELDS: CsvFieldDef[] = [
+  { key: 'invoiceNumber', label: 'Fakturanummer', required: true },
+  { key: 'customerName', label: 'Kund', required: true },
+  { key: 'currency', label: 'Valuta', required: true },
+  { key: 'foreignAmount', label: 'Belopp (utl. valuta)', required: true },
+  { key: 'bookedSekAmount', label: 'Bokfört (SEK)' },
+  { key: 'bookedRate', label: 'Bokförd kurs' },
+  { key: 'currentSekAmount', label: 'Aktuellt (SEK)' },
+  { key: 'currentRate', label: 'Aktuell kurs' },
+  { key: 'invoiceDate', label: 'Fakturadatum' },
+  { key: 'dueDate', label: 'Förfallodatum' },
+]
+
+const MOCK_CSV_TEMPLATE = `invoiceNumber;customerName;currency;foreignAmount;bookedSekAmount;bookedRate;currentSekAmount;currentRate;invoiceDate;dueDate
+1001;Beispiel GmbH;EUR;10000;112500;11.25;114200;11.42;2025-01-15;2025-02-15
+1002;Example Corp;USD;25000;262500;10.50;260000;10.40;2025-01-20;2025-02-20
+1003;London Ltd;GBP;8000;106400;13.30;108000;13.50;2025-02-01;2025-03-01`
+
+function parseMockCsvRows(rows: Record<string, string>[]): ReportData {
+  const today = new Date().toISOString().slice(0, 10)
+  const receivables: ForeignReceivable[] = rows.map(r => {
+    const foreignAmount = parseFloat(r.foreignAmount || '0') || 0
+    const bookedRate = parseFloat(r.bookedRate || '0') || 0
+    const currentRate = parseFloat(r.currentRate || '0') || bookedRate
+    const bookedSek = parseFloat(r.bookedSekAmount || '0') || Math.round(foreignAmount * bookedRate * 100) / 100
+    const currentSek = parseFloat(r.currentSekAmount || '0') || Math.round(foreignAmount * currentRate * 100) / 100
+    const invoiceDate = r.invoiceDate || today
+    const dueDate = r.dueDate || today
+    const daysOutstanding = Math.max(0, Math.floor((Date.now() - new Date(invoiceDate).getTime()) / 86400000))
+
+    return {
+      invoiceId: r.invoiceNumber || '',
+      invoiceNumber: r.invoiceNumber || '',
+      customerName: r.customerName || '',
+      customerCountry: '',
+      currency: r.currency || 'EUR',
+      foreignAmount,
+      bookedSekAmount: bookedSek,
+      bookedRate,
+      currentSekAmount: currentSek,
+      currentRate,
+      unrealizedGainLoss: Math.round((currentSek - bookedSek) * 100) / 100,
+      invoiceDate,
+      dueDate,
+      daysOutstanding,
+    }
+  })
+
+  // Group by currency for exposure
+  const currencyMap = new Map<string, CurrencyExposure>()
+  for (const r of receivables) {
+    const existing = currencyMap.get(r.currency)
+    if (existing) {
+      existing.totalForeignAmount += r.foreignAmount
+      existing.bookedSekValue += r.bookedSekAmount
+      existing.currentSekValue += r.currentSekAmount
+      existing.unrealizedGainLoss += r.unrealizedGainLoss
+      existing.invoiceCount++
+    } else {
+      currencyMap.set(r.currency, {
+        currency: r.currency,
+        totalForeignAmount: r.foreignAmount,
+        bookedSekValue: r.bookedSekAmount,
+        currentSekValue: r.currentSekAmount,
+        unrealizedGainLoss: r.unrealizedGainLoss,
+        invoiceCount: 1,
+        averageBookedRate: r.bookedRate,
+        currentRate: r.currentRate,
+      })
+    }
+  }
+
+  const exposureByCurrency = Array.from(currencyMap.values())
+  const totalBookedSek = receivables.reduce((s, r) => s + r.bookedSekAmount, 0)
+  const totalCurrentSek = receivables.reduce((s, r) => s + r.currentSekAmount, 0)
+  const totalUnrealized = Math.round((totalCurrentSek - totalBookedSek) * 100) / 100
+
+  return {
+    referenceDate: today,
+    exchangeRates: exposureByCurrency.map(e => ({ currency: e.currency, rate: e.currentRate, date: today })),
+    exposureByCurrency,
+    receivables,
+    realizedGainLoss: { year: new Date().getFullYear(), gains: 0, losses: 0, net: 0 },
+    monthlyTrend: [],
+    revalPreview: {
+      totalUnrealizedGainLoss: totalUnrealized,
+      gains: Math.max(0, totalUnrealized),
+      losses: Math.abs(Math.min(0, totalUnrealized)),
+    },
+    totals: {
+      bookedSekValue: totalBookedSek,
+      currentSekValue: totalCurrentSek,
+      totalUnrealizedGainLoss: totalUnrealized,
+      receivableCount: receivables.length,
+      currencyCount: exposureByCurrency.length,
+    },
+  }
+}
+
+function validateMockReport(data: unknown): { valid: boolean; error?: string } {
+  if (!data || typeof data !== 'object') return { valid: false, error: 'Data måste vara ett objekt' }
+  const obj = data as Record<string, unknown>
+  if (!Array.isArray(obj.receivables) && !Array.isArray(obj.exposureByCurrency)) {
+    return { valid: false, error: 'Fältet "receivables" eller "exposureByCurrency" saknas' }
+  }
+  if (!obj.totals || typeof obj.totals !== 'object') return { valid: false, error: 'Fältet "totals" saknas' }
+  return { valid: true }
+}
+
+// ── Component ─────────────────────────────────────────────────
+
+export default function CurrencyReceivablesWorkspace({ userId }: WorkspaceComponentProps) {
+  void userId
+
+  // Mock data
+  const { mockReport, isMockActive, isLoading: mockLoading, importedAt, saveMockData, clearMockData } = useMockData<ReportData>('export', 'currency-receivables')
+  const [importDialogOpen, setImportDialogOpen] = useState(false)
+
+  const [year, setYear] = useState(currentYear())
+  const [report, setReport] = useState<ReportData | null>(null)
+  const [isLoading, setIsLoading] = useState(true)
+  const [error, setError] = useState<string | null>(null)
+  const [refreshing, setRefreshing] = useState(false)
+
+  const [sortField, setSortField] = useState<SortField>('unrealizedGainLoss')
+  const [sortDir, setSortDir] = useState<SortDir>('desc')
+
+  const years = [currentYear(), currentYear() - 1, currentYear() - 2]
+
+  const fetchReport = useCallback(async () => {
+    if (isMockActive && mockReport) {
+      setReport(mockReport)
+      setIsLoading(false)
+      setRefreshing(false)
+      return
+    }
+
+    setIsLoading(true)
+    setError(null)
+    try {
+      const params = new URLSearchParams({ year: String(year) })
+      const res = await fetch(`/api/extensions/export/currency-receivables/report?${params}`)
+      if (!res.ok) {
+        const json = await res.json()
+        setError(json.error || 'Kunde inte hämta rapporten')
+        setReport(null)
+        return
+      }
+      const json = await res.json()
+      setReport(json.data)
+    } catch {
+      setError('Nätverksfel')
+      setReport(null)
+    } finally {
+      setIsLoading(false)
+      setRefreshing(false)
+    }
+  }, [year, isMockActive, mockReport])
+
+  useEffect(() => {
+    fetchReport()
+  }, [fetchReport])
+
+  const handleMockImport = useCallback(async (data: ReportData, meta: { source: 'csv' | 'json'; fileName: string; rowCount: number }) => {
+    await saveMockData(data, meta)
+    setReport(data)
+  }, [saveMockData])
+
+  const handleMockClear = useCallback(async () => {
+    await clearMockData()
+    setReport(null)
+    setIsLoading(true)
+    try {
+      const params = new URLSearchParams({ year: String(year) })
+      const res = await fetch(`/api/extensions/export/currency-receivables/report?${params}`)
+      if (res.ok) {
+        const json = await res.json()
+        setReport(json.data)
+      }
+    } catch { /* ignore */ }
+    setIsLoading(false)
+  }, [clearMockData, year])
+
+  const handleRefresh = () => {
+    setRefreshing(true)
+    fetchReport()
+  }
+
+  const toggleSort = (field: SortField) => {
+    if (sortField === field) {
+      setSortDir(d => d === 'asc' ? 'desc' : 'asc')
+    } else {
+      setSortField(field)
+      setSortDir('desc')
+    }
+  }
+
+  const sortedReceivables = report?.receivables.slice().sort((a, b) => {
+    const mul = sortDir === 'asc' ? 1 : -1
+    switch (sortField) {
+      case 'unrealizedGainLoss': return mul * (Math.abs(a.unrealizedGainLoss) - Math.abs(b.unrealizedGainLoss))
+      case 'foreignAmount': return mul * (a.foreignAmount - b.foreignAmount)
+      case 'daysOutstanding': return mul * (a.daysOutstanding - b.daysOutstanding)
+      case 'customerName': return mul * a.customerName.localeCompare(b.customerName)
+      default: return 0
+    }
+  }) || []
+
+  // Only show trend months that have data or are <= current month
+  const activeTrend = report?.monthlyTrend.filter(t => {
+    const m = parseInt(t.month.split('-')[1], 10)
+    const trendYear = parseInt(t.month.split('-')[0], 10)
+    if (trendYear < currentYear()) return true
+    return m <= new Date().getMonth() + 1
+  }) || []
+
+  if ((isLoading || mockLoading) && !report) {
+    return <ExtensionLoadingSkeleton />
+  }
+
+  return (
+    <div className="space-y-6">
+      {/* ── Header ─────────────────────────────────────── */}
+      <div className="flex flex-wrap items-end gap-3">
+        <div className="space-y-1.5">
+          <label className="text-xs font-medium text-muted-foreground">År (realiserade)</label>
+          <Select value={String(year)} onValueChange={v => setYear(parseInt(v, 10))}>
+            <SelectTrigger className="w-[100px]"><SelectValue /></SelectTrigger>
+            <SelectContent>
+              {years.map(y => <SelectItem key={y} value={String(y)}>{y}</SelectItem>)}
+            </SelectContent>
+          </Select>
+        </div>
+        <div className="flex gap-2 ml-auto">
+          <Button variant="outline" size="sm" onClick={() => setImportDialogOpen(true)}>
+            <FlaskConical className="h-4 w-4 mr-1.5" />
+            Importera testdata
+          </Button>
+          <Button variant="outline" size="sm" onClick={handleRefresh} disabled={refreshing}>
+            <RefreshCw className={cn('h-4 w-4 mr-1.5', refreshing && 'animate-spin')} />
+            {refreshing ? 'Uppdaterar...' : 'Uppdatera kurser'}
+          </Button>
+        </div>
+      </div>
+
+      {/* ── Mock Data Banner ──────────────────────────────── */}
+      {isMockActive && (
+        <MockDataBanner
+          importedAt={importedAt}
+          onClear={handleMockClear}
+          onReplace={() => setImportDialogOpen(true)}
+        />
+      )}
+
+      {error && (
+        <Card className="border-destructive/50 bg-destructive/5">
+          <CardContent className="pt-6">
+            <p className="text-sm text-destructive">{error}</p>
+          </CardContent>
+        </Card>
+      )}
+
+      {report && (
+        <>
+          {/* ── Exchange Rates ──────────────────────────── */}
+          <Card>
+            <CardContent className="pt-6">
+              <div className="flex items-center gap-2 mb-3">
+                <p className="text-sm font-medium">Växelkurser</p>
+                <Badge variant="outline" className="text-xs">
+                  {report.referenceDate}
+                </Badge>
+              </div>
+              <div className="flex flex-wrap gap-4">
+                {report.exchangeRates.map(r => (
+                  <div key={r.currency} className="flex items-baseline gap-1.5">
+                    <span className="text-xs font-medium text-muted-foreground">{r.currency}:</span>
+                    <span className="text-sm font-mono tabular-nums">{formatAmount(r.rate, 4)}</span>
+                  </div>
+                ))}
+              </div>
+            </CardContent>
+          </Card>
+
+          {/* ── Exposure Cards ─────────────────────────── */}
+          {report.exposureByCurrency.length > 0 ? (
+            <div className={cn(
+              'grid gap-4',
+              report.exposureByCurrency.length === 1 ? 'grid-cols-1 sm:grid-cols-2' :
+              report.exposureByCurrency.length === 2 ? 'grid-cols-1 sm:grid-cols-2' :
+              'grid-cols-1 sm:grid-cols-2 lg:grid-cols-3'
+            )}>
+              {report.exposureByCurrency.map(exp => (
+                <ExposureCard key={exp.currency} exposure={exp} />
+              ))}
+
+              {/* Total card */}
+              <Card className="border-2">
+                <CardContent className="pt-6">
+                  <div className="flex items-center justify-between mb-2">
+                    <span className="text-sm font-medium text-muted-foreground">Totalt</span>
+                    <Badge variant="outline">{report.totals.receivableCount} fakturor</Badge>
+                  </div>
+                  <p className="text-2xl font-semibold tabular-nums">
+                    {formatSEK(report.totals.currentSekValue)}
+                  </p>
+                  <p className="text-xs text-muted-foreground mt-0.5">SEK (aktuell kurs)</p>
+                  <div className="mt-3 pt-3 border-t">
+                    <FXIndicator label="Orealiserat" amount={report.totals.totalUnrealizedGainLoss} />
+                  </div>
+                </CardContent>
+              </Card>
+            </div>
+          ) : (
+            <Card>
+              <CardContent className="pt-6">
+                <p className="text-sm text-muted-foreground text-center py-6">
+                  Inga öppna fordringar i utländsk valuta.
+                </p>
+              </CardContent>
+            </Card>
+          )}
+
+          {/* ── Receivables Table ──────────────────────── */}
+          {sortedReceivables.length > 0 && (
+            <Card>
+              <CardHeader className="pb-3">
+                <CardTitle className="text-base">Öppna fordringar</CardTitle>
+              </CardHeader>
+              <CardContent>
+                <div className="overflow-x-auto">
+                  <Table>
+                    <TableHeader>
+                      <TableRow>
+                        <TableHead>Faktura</TableHead>
+                        <SortableHead field="customerName" label="Kund" current={sortField} dir={sortDir} onSort={toggleSort} />
+                        <TableHead>Valuta</TableHead>
+                        <SortableHead field="foreignAmount" label="Belopp" current={sortField} dir={sortDir} onSort={toggleSort} className="text-right" />
+                        <TableHead className="text-right">Bokfört (SEK)</TableHead>
+                        <TableHead className="text-right">Aktuellt (SEK)</TableHead>
+                        <SortableHead field="unrealizedGainLoss" label="Orealiserat" current={sortField} dir={sortDir} onSort={toggleSort} className="text-right" />
+                        <SortableHead field="daysOutstanding" label="Dagar" current={sortField} dir={sortDir} onSort={toggleSort} className="text-right" />
+                      </TableRow>
+                    </TableHeader>
+                    <TableBody>
+                      {sortedReceivables.map(r => (
+                        <TableRow key={r.invoiceId}>
+                          <TableCell className="font-mono text-sm">{r.invoiceNumber}</TableCell>
+                          <TableCell className="text-sm">
+                            <div>
+                              <span>{r.customerName}</span>
+                              {r.customerCountry && (
+                                <Badge variant="outline" className="ml-1.5 text-xs">{r.customerCountry}</Badge>
+                              )}
+                            </div>
+                          </TableCell>
+                          <TableCell>
+                            <Badge variant="outline" className="text-xs">{r.currency}</Badge>
+                          </TableCell>
+                          <TableCell className="text-right font-mono text-sm tabular-nums">
+                            {currencySymbol(r.currency)}{formatAmount(r.foreignAmount)}
+                          </TableCell>
+                          <TableCell className="text-right font-mono text-sm tabular-nums">
+                            {formatSEK(r.bookedSekAmount)}
+                          </TableCell>
+                          <TableCell className="text-right font-mono text-sm tabular-nums">
+                            {formatSEK(r.currentSekAmount)}
+                          </TableCell>
+                          <TableCell className="text-right">
+                            <FXBadge amount={r.unrealizedGainLoss} />
+                          </TableCell>
+                          <TableCell className="text-right text-sm tabular-nums">
+                            <span className={cn(
+                              r.daysOutstanding > 30 ? 'text-destructive font-medium' :
+                              r.daysOutstanding > 14 ? 'text-warning-foreground' : ''
+                            )}>
+                              {r.daysOutstanding}
+                            </span>
+                          </TableCell>
+                        </TableRow>
+                      ))}
+                    </TableBody>
+                  </Table>
+                </div>
+              </CardContent>
+            </Card>
+          )}
+
+          {/* ── Realized FX Trend ──────────────────────── */}
+          <Card>
+            <CardHeader className="pb-3">
+              <CardTitle className="text-base">
+                Realiserade kursdifferenser {year}
+              </CardTitle>
+            </CardHeader>
+            <CardContent>
+              {activeTrend.length === 0 ? (
+                <p className="text-sm text-muted-foreground text-center py-6">
+                  Inga realiserade kursdifferenser för {year}.
+                </p>
+              ) : (
+                <div className="overflow-x-auto">
+                  <Table>
+                    <TableHeader>
+                      <TableRow>
+                        <TableHead>Månad</TableHead>
+                        <TableHead className="text-right">Vinst (3960)</TableHead>
+                        <TableHead className="text-right">Förlust (7960)</TableHead>
+                        <TableHead className="text-right">Netto</TableHead>
+                      </TableRow>
+                    </TableHeader>
+                    <TableBody>
+                      {activeTrend.map(t => (
+                        <TableRow key={t.month}>
+                          <TableCell className="text-sm">{monthLabel(t.month)}</TableCell>
+                          <TableCell className="text-right font-mono text-sm tabular-nums text-green-600">
+                            {t.realizedGains > 0 ? `+${formatSEK(t.realizedGains)}` : '—'}
+                          </TableCell>
+                          <TableCell className="text-right font-mono text-sm tabular-nums text-red-600">
+                            {t.realizedLosses > 0 ? `-${formatSEK(t.realizedLosses)}` : '—'}
+                          </TableCell>
+                          <TableCell className="text-right font-mono text-sm tabular-nums">
+                            <FXBadge amount={t.netRealized} />
+                          </TableCell>
+                        </TableRow>
+                      ))}
+                      {/* Totals row */}
+                      <TableRow className="border-t-2 font-medium">
+                        <TableCell className="text-sm">Totalt {year}</TableCell>
+                        <TableCell className="text-right font-mono text-sm tabular-nums text-green-600">
+                          +{formatSEK(report.realizedGainLoss.gains)}
+                        </TableCell>
+                        <TableCell className="text-right font-mono text-sm tabular-nums text-red-600">
+                          -{formatSEK(report.realizedGainLoss.losses)}
+                        </TableCell>
+                        <TableCell className="text-right">
+                          <FXBadge amount={report.realizedGainLoss.net} />
+                        </TableCell>
+                      </TableRow>
+                    </TableBody>
+                  </Table>
+                </div>
+              )}
+            </CardContent>
+          </Card>
+
+          {/* ── Revaluation Preview ────────────────────── */}
+          {report.receivables.length > 0 && (
+            <Card className="border-l-4 border-l-blue-500/50">
+              <CardContent className="pt-6">
+                <div className="flex items-start gap-3">
+                  <Info className="h-5 w-5 text-blue-500 mt-0.5 shrink-0" />
+                  <div className="space-y-2">
+                    <p className="text-sm font-medium">Omvärdering vid periodbokslut</p>
+                    <p className="text-sm text-muted-foreground">
+                      Om bokslut görs idag: netto orealiserad{' '}
+                      <span className={cn(
+                        'font-medium',
+                        report.revalPreview.totalUnrealizedGainLoss >= 0 ? 'text-green-600' : 'text-red-600'
+                      )}>
+                        {report.revalPreview.totalUnrealizedGainLoss >= 0 ? 'vinst' : 'förlust'}{' '}
+                        {report.revalPreview.totalUnrealizedGainLoss >= 0 ? '+' : ''}
+                        {formatSEK(report.revalPreview.totalUnrealizedGainLoss)} SEK
+                      </span>
+                    </p>
+                    {report.revalPreview.gains > 0 && (
+                      <p className="text-xs text-muted-foreground">
+                        Konto 3969 (orealiserad kursvinst): {formatSEK(report.revalPreview.gains)} kr
+                      </p>
+                    )}
+                    {report.revalPreview.losses > 0 && (
+                      <p className="text-xs text-muted-foreground">
+                        Konto 7969 (orealiserad kursförlust): {formatSEK(report.revalPreview.losses)} kr
+                      </p>
+                    )}
+                    <p className="text-xs text-muted-foreground italic">
+                      Bokföringsposterna skapas inte av detta tillägg. Använd värdena ovan som underlag vid periodbokslut.
+                    </p>
+                  </div>
+                </div>
+              </CardContent>
+            </Card>
+          )}
+        </>
+      )}
+
+      {/* ── Mock Data Import Dialog ───────────────────────── */}
+      <MockDataImportDialog<ReportData>
+        open={importDialogOpen}
+        onOpenChange={setImportDialogOpen}
+        csvFields={MOCK_CSV_FIELDS}
+        parseCsvRows={parseMockCsvRows}
+        validateReport={validateMockReport}
+        templateCsvContent={MOCK_CSV_TEMPLATE}
+        templateFileName="currency-receivables-template.csv"
+        onImport={handleMockImport}
+      />
+    </div>
+  )
+}
+
+// ── Sub-components ────────────────────────────────────────────
+
+function ExposureCard({ exposure }: { exposure: CurrencyExposure }) {
+  const sym = currencySymbol(exposure.currency)
+  return (
+    <Card>
+      <CardContent className="pt-6">
+        <div className="flex items-center justify-between mb-2">
+          <Badge variant="outline" className="text-sm font-medium">{exposure.currency}</Badge>
+          <span className="text-xs text-muted-foreground">{exposure.invoiceCount} fakturor</span>
+        </div>
+        <p className="text-lg font-mono tabular-nums">
+          {sym}{formatAmount(exposure.totalForeignAmount)}
+        </p>
+        <p className="text-sm text-muted-foreground tabular-nums">
+          {formatSEK(exposure.currentSekValue)} SEK
+        </p>
+        <div className="mt-3 pt-3 border-t space-y-1">
+          <FXIndicator label="Orealiserat" amount={exposure.unrealizedGainLoss} />
+          <div className="flex justify-between text-xs text-muted-foreground">
+            <span>Bokförd kurs: {formatAmount(exposure.averageBookedRate, 4)}</span>
+            <span>Aktuell: {formatAmount(exposure.currentRate, 4)}</span>
+          </div>
+        </div>
+      </CardContent>
+    </Card>
+  )
+}
+
+function FXIndicator({ label, amount }: { label: string; amount: number }) {
+  const isGain = amount >= 0
+  return (
+    <div className="flex items-center justify-between">
+      <span className="text-xs text-muted-foreground">{label}</span>
+      <div className={cn(
+        'flex items-center gap-1 text-sm font-medium tabular-nums',
+        isGain ? 'text-green-600' : 'text-red-600'
+      )}>
+        {isGain ? <TrendingUp className="h-3.5 w-3.5" /> : <TrendingDown className="h-3.5 w-3.5" />}
+        <span>{isGain ? '+' : ''}{formatSEK(amount)} kr</span>
+      </div>
+    </div>
+  )
+}
+
+function FXBadge({ amount }: { amount: number }) {
+  if (amount === 0) return <span className="text-sm text-muted-foreground">—</span>
+  const isGain = amount > 0
+  return (
+    <span className={cn(
+      'text-sm font-mono tabular-nums font-medium',
+      isGain ? 'text-green-600' : 'text-red-600'
+    )}>
+      {isGain ? '+' : ''}{formatSEK(amount)}
+    </span>
+  )
+}
+
+function SortableHead({
+  field, label, current, dir, onSort, className,
+}: {
+  field: SortField
+  label: string
+  current: SortField
+  dir: SortDir
+  onSort: (f: SortField) => void
+  className?: string
+}) {
+  const isActive = current === field
+  return (
+    <TableHead className={className}>
+      <button
+        className="flex items-center gap-1 hover:text-foreground transition-colors"
+        onClick={() => onSort(field)}
+      >
+        {label}
+        <ArrowUpDown className={cn('h-3 w-3', isActive ? 'text-foreground' : 'text-muted-foreground/50')} />
+        {isActive && <span className="text-xs">{dir === 'asc' ? '↑' : '↓'}</span>}
+      </button>
+    </TableHead>
+  )
+}

components/extensions/export/EuSalesListWorkspace.tsx

@@ -0,0 +1,777 @@
+'use client'
+
+import { useState, useEffect, useMemo, useCallback } from 'react'
+import type { WorkspaceComponentProps } from '@/lib/extensions/workspace-registry'
+import { useMockData } from '@/lib/extensions/use-mock-data'
+import ExtensionLoadingSkeleton from '@/components/extensions/shared/ExtensionLoadingSkeleton'
+import MockDataBanner from '@/components/extensions/shared/MockDataBanner'
+import MockDataImportDialog from '@/components/extensions/shared/MockDataImportDialog'
+import type { CsvFieldDef } from '@/components/extensions/shared/MockDataImportDialog'
+import KPICard from '@/components/extensions/shared/KPICard'
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card'
+import { Badge } from '@/components/ui/badge'
+import { Button } from '@/components/ui/button'
+import {
+  Select, SelectContent, SelectItem, SelectTrigger, SelectValue,
+} from '@/components/ui/select'
+import {
+  Table, TableBody, TableCell, TableHead, TableHeader, TableRow,
+} from '@/components/ui/table'
+import {
+  AlertTriangle, CheckCircle2, FileSpreadsheet, FileCode,
+  Clock, ChevronDown, ChevronUp, Users, Package, Briefcase,
+  FlaskConical,
+} from 'lucide-react'
+import { cn } from '@/lib/utils'
+
+// ── Types ─────────────────────────────────────────────────────
+
+interface ECSalesListLine {
+  customerVatNumber: string
+  customerName: string
+  customerCountry: string
+  customerId: string
+  goodsAmount: number
+  servicesAmount: number
+  triangulationAmount: number
+  invoiceCount: number
+}
+
+interface ECSalesListWarning {
+  type: string
+  severity: 'error' | 'warning'
+  invoiceId?: string
+  invoiceNumber?: string
+  customerId?: string
+  customerName?: string
+  message: string
+}
+
+interface CrossCheckResult {
+  box35Match: boolean
+  box35ReportTotal: number
+  box35GLTotal: number
+  box39Match: boolean
+  box39ReportTotal: number
+  box39GLTotal: number
+}
+
+interface ReportData {
+  period: { year: number; month?: number; quarter?: number }
+  filingType: 'monthly' | 'quarterly'
+  reporterVatNumber: string
+  reporterName: string
+  lines: ECSalesListLine[]
+  totals: { goods: number; services: number; triangulation: number; total: number }
+  warnings: ECSalesListWarning[]
+  crossCheck: CrossCheckResult | null
+  invoiceCount: number
+  customerCount: number
+  deadline: string
+  daysUntilDeadline: number
+}
+
+type SortField = 'country' | 'vatNumber' | 'goods' | 'services' | 'invoices'
+type SortDir = 'asc' | 'desc'
+
+// ── Helpers ───────────────────────────────────────────────────
+
+function formatSEK(amount: number): string {
+  return Math.round(amount).toLocaleString('sv-SE')
+}
+
+function formatDeadlineDate(dateStr: string): string {
+  const d = new Date(dateStr + 'T00:00:00')
+  return d.toLocaleDateString('sv-SE', { year: 'numeric', month: 'long', day: 'numeric' })
+}
+
+const MONTHS = [
+  'Januari', 'Februari', 'Mars', 'April', 'Maj', 'Juni',
+  'Juli', 'Augusti', 'September', 'Oktober', 'November', 'December',
+]
+
+const QUARTERS = ['Q1 (jan–mar)', 'Q2 (apr–jun)', 'Q3 (jul–sep)', 'Q4 (okt–dec)']
+
+function currentYear(): number {
+  return new Date().getFullYear()
+}
+
+function currentMonth(): number {
+  return new Date().getMonth() + 1
+}
+
+function currentQuarter(): number {
+  return Math.ceil(currentMonth() / 3)
+}
+
+// ── Mock Data Config ──────────────────────────────────────────
+
+const MOCK_CSV_FIELDS: CsvFieldDef[] = [
+  { key: 'customerVatNumber', label: 'VAT-nummer', required: true },
+  { key: 'customerName', label: 'Kundnamn', required: true },
+  { key: 'customerCountry', label: 'Land', required: true },
+  { key: 'goodsAmount', label: 'Varor (SEK)' },
+  { key: 'servicesAmount', label: 'Tjänster (SEK)' },
+  { key: 'triangulationAmount', label: 'Trepartshandel (SEK)' },
+  { key: 'invoiceCount', label: 'Antal fakturor' },
+]
+
+const MOCK_CSV_TEMPLATE = `customerVatNumber;customerName;customerCountry;goodsAmount;servicesAmount;triangulationAmount;invoiceCount
+DE123456789;Beispiel GmbH;DE;150000;25000;0;3
+FR987654321;Exemple SARL;FR;0;80000;0;2
+NL456789012;Voorbeeld BV;NL;45000;0;12000;1`
+
+function parseMockCsvRows(rows: Record<string, string>[]): ReportData {
+  const lines: ECSalesListLine[] = rows.map(r => ({
+    customerVatNumber: r.customerVatNumber || '',
+    customerName: r.customerName || '',
+    customerCountry: r.customerCountry || '',
+    customerId: r.customerVatNumber || '',
+    goodsAmount: parseFloat(r.goodsAmount || '0') || 0,
+    servicesAmount: parseFloat(r.servicesAmount || '0') || 0,
+    triangulationAmount: parseFloat(r.triangulationAmount || '0') || 0,
+    invoiceCount: parseInt(r.invoiceCount || '1', 10) || 1,
+  }))
+
+  const goods = lines.reduce((s, l) => s + l.goodsAmount, 0)
+  const services = lines.reduce((s, l) => s + l.servicesAmount, 0)
+  const triangulation = lines.reduce((s, l) => s + l.triangulationAmount, 0)
+  const invoiceCount = lines.reduce((s, l) => s + l.invoiceCount, 0)
+
+  return {
+    period: { year: new Date().getFullYear(), quarter: Math.ceil((new Date().getMonth() + 1) / 3) },
+    filingType: 'quarterly',
+    reporterVatNumber: 'SE000000000001',
+    reporterName: 'Testdata',
+    lines,
+    totals: { goods, services, triangulation, total: goods + services + triangulation },
+    warnings: [],
+    crossCheck: null,
+    invoiceCount,
+    customerCount: lines.length,
+    deadline: new Date(Date.now() + 30 * 86400000).toISOString().slice(0, 10),
+    daysUntilDeadline: 30,
+  }
+}
+
+function validateMockReport(data: unknown): { valid: boolean; error?: string } {
+  if (!data || typeof data !== 'object') return { valid: false, error: 'Data måste vara ett objekt' }
+  const obj = data as Record<string, unknown>
+  if (!Array.isArray(obj.lines)) return { valid: false, error: 'Fältet "lines" saknas eller är inte en array' }
+  if (!obj.totals || typeof obj.totals !== 'object') return { valid: false, error: 'Fältet "totals" saknas' }
+  return { valid: true }
+}
+
+// ── Component ─────────────────────────────────────────────────
+
+export default function EuSalesListWorkspace({ userId }: WorkspaceComponentProps) {
+  void userId
+
+  // Mock data
+  const { mockReport, isMockActive, isLoading: mockLoading, importedAt, saveMockData, clearMockData } = useMockData<ReportData>('export', 'eu-sales-list')
+  const [importDialogOpen, setImportDialogOpen] = useState(false)
+
+  // Period selection state
+  const [year, setYear] = useState(currentYear())
+  const [periodType, setPeriodType] = useState<'monthly' | 'quarterly'>('quarterly')
+  const [month, setMonth] = useState(currentMonth())
+  const [quarter, setQuarter] = useState(currentQuarter())
+
+  // Report state
+  const [report, setReport] = useState<ReportData | null>(null)
+  const [isLoading, setIsLoading] = useState(true)
+  const [error, setError] = useState<string | null>(null)
+
+  // Table sort
+  const [sortField, setSortField] = useState<SortField>('country')
+  const [sortDir, setSortDir] = useState<SortDir>('asc')
+
+  // Warning expansion
+  const [warningsExpanded, setWarningsExpanded] = useState(false)
+
+  // Download state
+  const [downloading, setDownloading] = useState<'csv' | 'xml' | null>(null)
+
+  // Available years (current year and 2 previous)
+  const years = useMemo(() => {
+    const cy = currentYear()
+    return [cy, cy - 1, cy - 2]
+  }, [])
+
+  // Fetch report
+  const fetchReport = useCallback(async () => {
+    if (isMockActive && mockReport) {
+      setReport(mockReport)
+      setIsLoading(false)
+      return
+    }
+
+    setIsLoading(true)
+    setError(null)
+
+    const params = new URLSearchParams({ year: String(year) })
+    if (periodType === 'monthly') {
+      params.set('month', String(month))
+    } else {
+      params.set('quarter', String(quarter))
+    }
+
+    try {
+      const res = await fetch(`/api/extensions/export/eu-sales-list/report?${params}`)
+      if (!res.ok) {
+        const json = await res.json()
+        setError(json.error || 'Kunde inte generera rapporten')
+        setReport(null)
+        return
+      }
+      const json = await res.json()
+      setReport(json.data)
+    } catch {
+      setError('Nätverksfel — kunde inte hämta rapporten')
+      setReport(null)
+    } finally {
+      setIsLoading(false)
+    }
+  }, [year, month, quarter, periodType, isMockActive, mockReport])
+
+  useEffect(() => {
+    fetchReport()
+  }, [fetchReport])
+
+  const handleMockImport = useCallback(async (data: ReportData, meta: { source: 'csv' | 'json'; fileName: string; rowCount: number }) => {
+    await saveMockData(data, meta)
+    setReport(data)
+  }, [saveMockData])
+
+  const handleMockClear = useCallback(async () => {
+    await clearMockData()
+    setReport(null)
+    // Re-fetch from API
+    setIsLoading(true)
+    setError(null)
+    const params = new URLSearchParams({ year: String(year) })
+    if (periodType === 'monthly') {
+      params.set('month', String(month))
+    } else {
+      params.set('quarter', String(quarter))
+    }
+    try {
+      const res = await fetch(`/api/extensions/export/eu-sales-list/report?${params}`)
+      if (res.ok) {
+        const json = await res.json()
+        setReport(json.data)
+      }
+    } catch { /* ignore */ }
+    setIsLoading(false)
+  }, [clearMockData, year, month, quarter, periodType])
+
+  // Sort lines
+  const sortedLines = useMemo(() => {
+    if (!report) return []
+    const lines = [...report.lines]
+    lines.sort((a, b) => {
+      let cmp = 0
+      switch (sortField) {
+        case 'country':
+          cmp = a.customerCountry.localeCompare(b.customerCountry)
+          break
+        case 'vatNumber':
+          cmp = a.customerVatNumber.localeCompare(b.customerVatNumber)
+          break
+        case 'goods':
+          cmp = a.goodsAmount - b.goodsAmount
+          break
+        case 'services':
+          cmp = a.servicesAmount - b.servicesAmount
+          break
+        case 'invoices':
+          cmp = a.invoiceCount - b.invoiceCount
+          break
+      }
+      return sortDir === 'asc' ? cmp : -cmp
+    })
+    return lines
+  }, [report, sortField, sortDir])
+
+  // Toggle sort
+  const toggleSort = (field: SortField) => {
+    if (sortField === field) {
+      setSortDir(d => d === 'asc' ? 'desc' : 'asc')
+    } else {
+      setSortField(field)
+      setSortDir('asc')
+    }
+  }
+
+  // Download handler
+  const handleDownload = async (format: 'csv' | 'xml') => {
+    setDownloading(format)
+    const params = new URLSearchParams({ year: String(year), format })
+    if (periodType === 'monthly') {
+      params.set('month', String(month))
+    } else {
+      params.set('quarter', String(quarter))
+    }
+
+    try {
+      const res = await fetch(`/api/extensions/export/eu-sales-list/download?${params}`)
+      if (!res.ok) {
+        const json = await res.json()
+        setError(json.error || 'Kunde inte ladda ner filen')
+        return
+      }
+
+      const blob = await res.blob()
+      const disposition = res.headers.get('Content-Disposition') || ''
+      const filenameMatch = disposition.match(/filename="(.+)"/)
+      const filename = filenameMatch ? filenameMatch[1] : `PS_${year}.${format}`
+
+      const url = URL.createObjectURL(blob)
+      const a = document.createElement('a')
+      a.href = url
+      a.download = filename
+      document.body.appendChild(a)
+      a.click()
+      document.body.removeChild(a)
+      URL.revokeObjectURL(url)
+    } catch {
+      setError('Kunde inte ladda ner filen')
+    } finally {
+      setDownloading(null)
+    }
+  }
+
+  // Derived counts
+  const errorCount = report?.warnings.filter(w => w.severity === 'error').length ?? 0
+  const warningCount = report?.warnings.filter(w => w.severity === 'warning').length ?? 0
+
+  if ((isLoading || mockLoading) && !report) {
+    return <ExtensionLoadingSkeleton />
+  }
+
+  return (
+    <div className="space-y-6">
+      {/* ── Period Selector ─────────────────────────────────── */}
+      <div className="flex flex-wrap items-end gap-3">
+        <div className="space-y-1.5">
+          <label className="text-xs font-medium text-muted-foreground">År</label>
+          <Select value={String(year)} onValueChange={v => setYear(parseInt(v, 10))}>
+            <SelectTrigger className="w-[100px]">
+              <SelectValue />
+            </SelectTrigger>
+            <SelectContent>
+              {years.map(y => (
+                <SelectItem key={y} value={String(y)}>{y}</SelectItem>
+              ))}
+            </SelectContent>
+          </Select>
+        </div>
+
+        <div className="space-y-1.5">
+          <label className="text-xs font-medium text-muted-foreground">Periodtyp</label>
+          <Select value={periodType} onValueChange={v => setPeriodType(v as 'monthly' | 'quarterly')}>
+            <SelectTrigger className="w-[130px]">
+              <SelectValue />
+            </SelectTrigger>
+            <SelectContent>
+              <SelectItem value="monthly">Månad</SelectItem>
+              <SelectItem value="quarterly">Kvartal</SelectItem>
+            </SelectContent>
+          </Select>
+        </div>
+
+        <div className="space-y-1.5">
+          <label className="text-xs font-medium text-muted-foreground">
+            {periodType === 'monthly' ? 'Månad' : 'Kvartal'}
+          </label>
+          {periodType === 'monthly' ? (
+            <Select value={String(month)} onValueChange={v => setMonth(parseInt(v, 10))}>
+              <SelectTrigger className="w-[150px]">
+                <SelectValue />
+              </SelectTrigger>
+              <SelectContent>
+                {MONTHS.map((name, i) => (
+                  <SelectItem key={i + 1} value={String(i + 1)}>{name}</SelectItem>
+                ))}
+              </SelectContent>
+            </Select>
+          ) : (
+            <Select value={String(quarter)} onValueChange={v => setQuarter(parseInt(v, 10))}>
+              <SelectTrigger className="w-[150px]">
+                <SelectValue />
+              </SelectTrigger>
+              <SelectContent>
+                {QUARTERS.map((name, i) => (
+                  <SelectItem key={i + 1} value={String(i + 1)}>{name}</SelectItem>
+                ))}
+              </SelectContent>
+            </Select>
+          )}
+        </div>
+
+        {/* Download + Import buttons */}
+        <div className="flex gap-2 ml-auto">
+          <Button
+            variant="outline"
+            size="sm"
+            onClick={() => setImportDialogOpen(true)}
+          >
+            <FlaskConical className="h-4 w-4 mr-1.5" />
+            Importera testdata
+          </Button>
+          <Button
+            variant="outline"
+            size="sm"
+            onClick={() => handleDownload('csv')}
+            disabled={downloading !== null || !report || report.lines.length === 0}
+          >
+            <FileSpreadsheet className="h-4 w-4 mr-1.5" />
+            {downloading === 'csv' ? 'Laddar...' : 'CSV'}
+          </Button>
+          <Button
+            variant="outline"
+            size="sm"
+            onClick={() => handleDownload('xml')}
+            disabled={downloading !== null || !report || report.lines.length === 0}
+          >
+            <FileCode className="h-4 w-4 mr-1.5" />
+            {downloading === 'xml' ? 'Laddar...' : 'SKV XML'}
+          </Button>
+        </div>
+      </div>
+
+      {/* ── Mock Data Banner ──────────────────────────────── */}
+      {isMockActive && (
+        <MockDataBanner
+          importedAt={importedAt}
+          onClear={handleMockClear}
+          onReplace={() => setImportDialogOpen(true)}
+        />
+      )}
+
+      {/* ── Error state ────────────────────────────────────── */}
+      {error && (
+        <Card className="border-destructive/50 bg-destructive/5">
+          <CardContent className="pt-6">
+            <p className="text-sm text-destructive">{error}</p>
+          </CardContent>
+        </Card>
+      )}
+
+      {report && (
+        <>
+          {/* ── KPI Cards ────────────────────────────────────── */}
+          <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-4">
+            <KPICard
+              label="Varuförsäljning EU"
+              value={formatSEK(report.totals.goods)}
+              suffix="SEK"
+            />
+            <KPICard
+              label="Tjänsteförsäljning EU"
+              value={formatSEK(report.totals.services)}
+              suffix="SEK"
+            />
+            <KPICard
+              label="Trepartshandel"
+              value={formatSEK(report.totals.triangulation)}
+              suffix="SEK"
+            />
+            <KPICard
+              label="Kunder"
+              value={report.customerCount}
+              suffix={`(${report.invoiceCount} fakturor)`}
+            />
+          </div>
+
+          {/* ── Deadline + Cross-Check Row ────────────────────── */}
+          <div className="grid grid-cols-1 lg:grid-cols-2 gap-4">
+            {/* Deadline */}
+            <Card>
+              <CardContent className="pt-6">
+                <div className="flex items-start gap-3">
+                  <Clock className="h-5 w-5 text-muted-foreground mt-0.5 shrink-0" />
+                  <div>
+                    <p className="text-sm font-medium">Inlämningsdeadline</p>
+                    <p className="text-lg font-semibold mt-0.5">
+                      {formatDeadlineDate(report.deadline)}
+                    </p>
+                    <p className={cn(
+                      'text-sm mt-1',
+                      report.daysUntilDeadline <= 7 ? 'text-destructive font-medium' :
+                      report.daysUntilDeadline <= 14 ? 'text-warning-foreground' :
+                      'text-muted-foreground'
+                    )}>
+                      {report.daysUntilDeadline > 0
+                        ? `${report.daysUntilDeadline} dagar kvar`
+                        : report.daysUntilDeadline === 0
+                          ? 'Deadline idag!'
+                          : `${Math.abs(report.daysUntilDeadline)} dagar försenad`
+                      }
+                    </p>
+                  </div>
+                </div>
+              </CardContent>
+            </Card>
+
+            {/* Cross-check */}
+            <Card>
+              <CardContent className="pt-6">
+                <p className="text-sm font-medium mb-3">Avstämning mot huvudbok</p>
+                {report.crossCheck ? (
+                  <div className="space-y-2">
+                    <CrossCheckRow
+                      label="Ruta 35 — varor"
+                      reportTotal={report.crossCheck.box35ReportTotal}
+                      glTotal={report.crossCheck.box35GLTotal}
+                      match={report.crossCheck.box35Match}
+                    />
+                    <CrossCheckRow
+                      label="Ruta 39 — tjänster"
+                      reportTotal={report.crossCheck.box39ReportTotal}
+                      glTotal={report.crossCheck.box39GLTotal}
+                      match={report.crossCheck.box39Match}
+                    />
+                  </div>
+                ) : (
+                  <p className="text-sm text-muted-foreground">
+                    Ingen bokföringsdata tillgänglig för perioden.
+                  </p>
+                )}
+              </CardContent>
+            </Card>
+          </div>
+
+          {/* ── Warnings ─────────────────────────────────────── */}
+          {report.warnings.length > 0 && (
+            <Card className={cn(
+              'border-l-4',
+              errorCount > 0 ? 'border-l-destructive' : 'border-l-warning'
+            )}>
+              <CardContent className="pt-6">
+                <button
+                  className="flex items-center gap-2 w-full text-left"
+                  onClick={() => setWarningsExpanded(!warningsExpanded)}
+                >
+                  <AlertTriangle className={cn(
+                    'h-4 w-4 shrink-0',
+                    errorCount > 0 ? 'text-destructive' : 'text-warning-foreground'
+                  )} />
+                  <span className="text-sm font-medium flex-1">
+                    {errorCount > 0 && (
+                      <span className="text-destructive">{errorCount} fel</span>
+                    )}
+                    {errorCount > 0 && warningCount > 0 && ', '}
+                    {warningCount > 0 && (
+                      <span className="text-warning-foreground">{warningCount} varningar</span>
+                    )}
+                  </span>
+                  {warningsExpanded
+                    ? <ChevronUp className="h-4 w-4 text-muted-foreground" />
+                    : <ChevronDown className="h-4 w-4 text-muted-foreground" />
+                  }
+                </button>
+
+                {warningsExpanded && (
+                  <div className="mt-4 space-y-2">
+                    {report.warnings.map((w, i) => (
+                      <div
+                        key={i}
+                        className={cn(
+                          'flex items-start gap-2 text-sm py-2 px-3 rounded-md',
+                          w.severity === 'error'
+                            ? 'bg-destructive/5 text-destructive'
+                            : 'bg-warning/10 text-warning-foreground'
+                        )}
+                      >
+                        <AlertTriangle className="h-3.5 w-3.5 mt-0.5 shrink-0" />
+                        <span>{w.message}</span>
+                      </div>
+                    ))}
+                  </div>
+                )}
+              </CardContent>
+            </Card>
+          )}
+
+          {/* ── Customer Table ────────────────────────────────── */}
+          <Card>
+            <CardHeader className="pb-3">
+              <CardTitle className="text-base flex items-center gap-2">
+                <Users className="h-4 w-4" />
+                Kunder per land
+              </CardTitle>
+            </CardHeader>
+            <CardContent>
+              {sortedLines.length === 0 ? (
+                <p className="text-sm text-muted-foreground py-8 text-center">
+                  Inga EU-försäljningar hittades för vald period.
+                </p>
+              ) : (
+                <div className="overflow-x-auto">
+                  <Table>
+                    <TableHeader>
+                      <TableRow>
+                        <SortableHead field="country" current={sortField} dir={sortDir} onSort={toggleSort}>
+                          Land
+                        </SortableHead>
+                        <SortableHead field="vatNumber" current={sortField} dir={sortDir} onSort={toggleSort}>
+                          VAT-nummer
+                        </SortableHead>
+                        <TableHead className="text-left">Kund</TableHead>
+                        <SortableHead field="goods" current={sortField} dir={sortDir} onSort={toggleSort} className="text-right">
+                          <span className="inline-flex items-center gap-1">
+                            <Package className="h-3.5 w-3.5" />
+                            Varor (ruta 35)
+                          </span>
+                        </SortableHead>
+                        <SortableHead field="services" current={sortField} dir={sortDir} onSort={toggleSort} className="text-right">
+                          <span className="inline-flex items-center gap-1">
+                            <Briefcase className="h-3.5 w-3.5" />
+                            Tjänster (ruta 39)
+                          </span>
+                        </SortableHead>
+                        <SortableHead field="invoices" current={sortField} dir={sortDir} onSort={toggleSort} className="text-right">
+                          Fakturor
+                        </SortableHead>
+                      </TableRow>
+                    </TableHeader>
+                    <TableBody>
+                      {sortedLines.map(line => (
+                        <TableRow key={line.customerVatNumber}>
+                          <TableCell>
+                            <Badge variant="outline" className="font-mono text-xs">
+                              {line.customerCountry}
+                            </Badge>
+                          </TableCell>
+                          <TableCell className="font-mono text-sm">
+                            {line.customerVatNumber}
+                          </TableCell>
+                          <TableCell className="text-sm">{line.customerName}</TableCell>
+                          <TableCell className="text-right font-mono text-sm tabular-nums">
+                            {line.goodsAmount !== 0 ? formatSEK(line.goodsAmount) : '—'}
+                          </TableCell>
+                          <TableCell className="text-right font-mono text-sm tabular-nums">
+                            {line.servicesAmount !== 0 ? formatSEK(line.servicesAmount) : '—'}
+                          </TableCell>
+                          <TableCell className="text-right text-sm tabular-nums">
+                            {line.invoiceCount}
+                          </TableCell>
+                        </TableRow>
+                      ))}
+
+                      {/* Totals row */}
+                      <TableRow className="border-t-2 font-medium">
+                        <TableCell colSpan={3} className="text-sm">
+                          Summa ({sortedLines.length} kunder)
+                        </TableCell>
+                        <TableCell className="text-right font-mono text-sm tabular-nums">
+                          {formatSEK(report.totals.goods)}
+                        </TableCell>
+                        <TableCell className="text-right font-mono text-sm tabular-nums">
+                          {formatSEK(report.totals.services)}
+                        </TableCell>
+                        <TableCell className="text-right text-sm tabular-nums">
+                          {report.invoiceCount}
+                        </TableCell>
+                      </TableRow>
+                    </TableBody>
+                  </Table>
+                </div>
+              )}
+            </CardContent>
+          </Card>
+
+          {/* ── Filing Info Footer ────────────────────────────── */}
+          <div className="flex items-center justify-between text-xs text-muted-foreground px-1">
+            <span>
+              Uppgiftslämnare: {report.reporterName} ({report.reporterVatNumber})
+            </span>
+            <span>
+              Redovisningsperiod: {report.period.year}
+              {report.period.month !== undefined && `, ${MONTHS[report.period.month - 1]}`}
+              {report.period.quarter !== undefined && `, ${QUARTERS[report.period.quarter - 1]}`}
+            </span>
+          </div>
+        </>
+      )}
+
+      {/* ── Mock Data Import Dialog ───────────────────────── */}
+      <MockDataImportDialog<ReportData>
+        open={importDialogOpen}
+        onOpenChange={setImportDialogOpen}
+        csvFields={MOCK_CSV_FIELDS}
+        parseCsvRows={parseMockCsvRows}
+        validateReport={validateMockReport}
+        templateCsvContent={MOCK_CSV_TEMPLATE}
+        templateFileName="eu-sales-list-template.csv"
+        onImport={handleMockImport}
+      />
+    </div>
+  )
+}
+
+// ── Sub-components ────────────────────────────────────────────
+
+function CrossCheckRow({
+  label,
+  reportTotal,
+  glTotal,
+  match,
+}: {
+  label: string
+  reportTotal: number
+  glTotal: number
+  match: boolean
+}) {
+  const diff = Math.round(reportTotal * 100) / 100 - Math.round(glTotal * 100) / 100
+
+  return (
+    <div className="flex items-center gap-2 text-sm">
+      {match ? (
+        <CheckCircle2 className="h-4 w-4 text-green-600 shrink-0" />
+      ) : (
+        <AlertTriangle className="h-4 w-4 text-destructive shrink-0" />
+      )}
+      <span className="flex-1">{label}</span>
+      <span className="font-mono tabular-nums text-muted-foreground">
+        {formatSEK(reportTotal)} SEK
+      </span>
+      {!match && (
+        <span className="font-mono tabular-nums text-destructive text-xs">
+          (diff: {diff > 0 ? '+' : ''}{formatSEK(diff)})
+        </span>
+      )}
+    </div>
+  )
+}
+
+function SortableHead({
+  field,
+  current,
+  dir,
+  onSort,
+  className,
+  children,
+}: {
+  field: SortField
+  current: SortField
+  dir: SortDir
+  onSort: (field: SortField) => void
+  className?: string
+  children: React.ReactNode
+}) {
+  const isActive = current === field
+  return (
+    <TableHead className={cn('cursor-pointer select-none', className)} onClick={() => onSort(field)}>
+      <span className="inline-flex items-center gap-1">
+        {children}
+        {isActive && (
+          dir === 'asc'
+            ? <ChevronUp className="h-3 w-3" />
+            : <ChevronDown className="h-3 w-3" />
+        )}
+      </span>
+    </TableHead>
+  )
+}

components/extensions/export/IntrastatWorkspace.tsx

@@ -0,0 +1,747 @@
+'use client'
+
+import { useState, useEffect, useMemo, useCallback } from 'react'
+import type { WorkspaceComponentProps } from '@/lib/extensions/workspace-registry'
+import { useExtensionData } from '@/lib/extensions/use-extension-data'
+import { useMockData } from '@/lib/extensions/use-mock-data'
+import ExtensionLoadingSkeleton from '@/components/extensions/shared/ExtensionLoadingSkeleton'
+import MockDataBanner from '@/components/extensions/shared/MockDataBanner'
+import MockDataImportDialog from '@/components/extensions/shared/MockDataImportDialog'
+import type { CsvFieldDef } from '@/components/extensions/shared/MockDataImportDialog'
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card'
+import { Badge } from '@/components/ui/badge'
+import { Button } from '@/components/ui/button'
+import { Input } from '@/components/ui/input'
+import { Label } from '@/components/ui/label'
+import { Progress } from '@/components/ui/progress'
+import {
+  Select, SelectContent, SelectItem, SelectTrigger, SelectValue,
+} from '@/components/ui/select'
+import {
+  Table, TableBody, TableCell, TableHead, TableHeader, TableRow,
+} from '@/components/ui/table'
+import {
+  Dialog, DialogContent, DialogHeader, DialogTitle, DialogFooter,
+} from '@/components/ui/dialog'
+import {
+  AlertTriangle, Plus, Pencil, Trash2, FileSpreadsheet, Clock,
+  ChevronDown, ChevronUp, Package, FlaskConical,
+} from 'lucide-react'
+import { cn } from '@/lib/utils'
+
+// ── Types ─────────────────────────────────────────────────────
+
+interface IntrastatLine {
+  cnCode: string
+  partnerCountry: string
+  countryOfOrigin: string
+  transactionNature: string
+  deliveryTerms: string
+  invoicedValue: number
+  netMass: number
+  supplementaryUnit: number | null
+  supplementaryUnitType: string | null
+  partnerVatId: string
+}
+
+interface ThresholdStatus {
+  cumulativeValue: number
+  threshold: number
+  isObligated: boolean
+  percentageUsed: number
+}
+
+interface IntrastatWarning {
+  type: string
+  severity: 'error' | 'warning'
+  invoiceId?: string
+  invoiceNumber?: string
+  productId?: string
+  message: string
+}
+
+interface ReportData {
+  period: { year: number; month: number }
+  reporterVatNumber: string
+  reporterName: string
+  lines: IntrastatLine[]
+  totals: { invoicedValue: number; netMass: number; lineCount: number }
+  thresholdStatus: ThresholdStatus
+  warnings: IntrastatWarning[]
+  invoiceCount: number
+}
+
+interface ProductRecord {
+  key: string
+  productId: string
+  description: string
+  cn_code: string | null
+  net_weight_kg: number | null
+  country_of_origin: string
+}
+
+interface ProductForm {
+  productId: string
+  description: string
+  cnCode: string
+  netWeightKg: string
+  countryOfOrigin: string
+}
+
+// ── Helpers ───────────────────────────────────────────────────
+
+function formatSEK(amount: number): string {
+  return Math.round(amount).toLocaleString('sv-SE')
+}
+
+const MONTHS = [
+  'Januari', 'Februari', 'Mars', 'April', 'Maj', 'Juni',
+  'Juli', 'Augusti', 'September', 'Oktober', 'November', 'December',
+]
+
+function currentYear(): number { return new Date().getFullYear() }
+function currentMonth(): number { return new Date().getMonth() + 1 }
+
+const EMPTY_PRODUCT: ProductForm = {
+  productId: '', description: '', cnCode: '', netWeightKg: '', countryOfOrigin: 'SE',
+}
+
+// ── Mock Data Config ──────────────────────────────────────────
+
+const MOCK_CSV_FIELDS: CsvFieldDef[] = [
+  { key: 'cnCode', label: 'CN-kod', required: true },
+  { key: 'partnerCountry', label: 'Partnerland', required: true },
+  { key: 'countryOfOrigin', label: 'Ursprungsland' },
+  { key: 'transactionNature', label: 'Transaktionstyp' },
+  { key: 'deliveryTerms', label: 'Leveransvillkor' },
+  { key: 'invoicedValue', label: 'Fakturerat värde (SEK)', required: true },
+  { key: 'netMass', label: 'Nettovikt (kg)' },
+  { key: 'partnerVatId', label: 'Partner VAT-ID' },
+]
+
+const MOCK_CSV_TEMPLATE = `cnCode;partnerCountry;countryOfOrigin;transactionNature;deliveryTerms;invoicedValue;netMass;partnerVatId
+72163100;DE;SE;11;DAP;245000;4500;DE123456789
+84713000;FR;CN;11;EXW;128000;85;FR987654321
+39269090;NL;SE;11;FCA;67000;320;NL456789012`
+
+function parseMockCsvRows(rows: Record<string, string>[]): ReportData {
+  const lines: IntrastatLine[] = rows.map(r => ({
+    cnCode: r.cnCode || '00000000',
+    partnerCountry: r.partnerCountry || '',
+    countryOfOrigin: r.countryOfOrigin || 'SE',
+    transactionNature: r.transactionNature || '11',
+    deliveryTerms: r.deliveryTerms || 'DAP',
+    invoicedValue: parseFloat(r.invoicedValue || '0') || 0,
+    netMass: parseFloat(r.netMass || '0') || 0,
+    supplementaryUnit: null,
+    supplementaryUnitType: null,
+    partnerVatId: r.partnerVatId || '',
+  }))
+
+  const invoicedValue = lines.reduce((s, l) => s + l.invoicedValue, 0)
+  const netMass = lines.reduce((s, l) => s + l.netMass, 0)
+
+  return {
+    period: { year: new Date().getFullYear(), month: new Date().getMonth() + 1 },
+    reporterVatNumber: 'SE000000000001',
+    reporterName: 'Testdata',
+    lines,
+    totals: { invoicedValue, netMass, lineCount: lines.length },
+    thresholdStatus: {
+      cumulativeValue: invoicedValue,
+      threshold: 9000000,
+      isObligated: invoicedValue >= 9000000,
+      percentageUsed: Math.round(invoicedValue / 9000000 * 100),
+    },
+    warnings: [],
+    invoiceCount: lines.length,
+  }
+}
+
+function validateMockReport(data: unknown): { valid: boolean; error?: string } {
+  if (!data || typeof data !== 'object') return { valid: false, error: 'Data måste vara ett objekt' }
+  const obj = data as Record<string, unknown>
+  if (!Array.isArray(obj.lines)) return { valid: false, error: 'Fältet "lines" saknas eller är inte en array' }
+  if (!obj.totals || typeof obj.totals !== 'object') return { valid: false, error: 'Fältet "totals" saknas' }
+  return { valid: true }
+}
+
+// ── Component ─────────────────────────────────────────────────
+
+export default function IntrastatWorkspace({ userId }: WorkspaceComponentProps) {
+  void userId
+
+  // Mock data
+  const { mockReport, isMockActive, isLoading: mockLoading, importedAt, saveMockData, clearMockData } = useMockData<ReportData>('export', 'intrastat')
+  const [importDialogOpen, setImportDialogOpen] = useState(false)
+
+  const [year, setYear] = useState(currentYear())
+  const [month, setMonth] = useState(currentMonth())
+
+  const [report, setReport] = useState<ReportData | null>(null)
+  const [isLoading, setIsLoading] = useState(true)
+  const [error, setError] = useState<string | null>(null)
+  const [downloading, setDownloading] = useState(false)
+
+  const [warningsExpanded, setWarningsExpanded] = useState(false)
+
+  // Product CRUD
+  const { data: extData, save, remove, isLoading: productsLoading } = useExtensionData('export', 'intrastat')
+  const [productDialogOpen, setProductDialogOpen] = useState(false)
+  const [editingProduct, setEditingProduct] = useState<string | null>(null)
+  const [productForm, setProductForm] = useState<ProductForm>(EMPTY_PRODUCT)
+  const [deleteConfirm, setDeleteConfirm] = useState<string | null>(null)
+
+  const years = useMemo(() => {
+    const cy = currentYear()
+    return [cy, cy - 1, cy - 2]
+  }, [])
+
+  // Parse products from extension data
+  const products: ProductRecord[] = useMemo(() => {
+    return extData
+      .filter(d => d.key.startsWith('product:'))
+      .map(d => ({
+        key: d.key,
+        productId: d.key.replace('product:', ''),
+        description: String(d.value.description || ''),
+        cn_code: d.value.cn_code ? String(d.value.cn_code) : null,
+        net_weight_kg: d.value.net_weight_kg !== undefined ? Number(d.value.net_weight_kg) : null,
+        country_of_origin: String(d.value.country_of_origin || 'SE'),
+      }))
+      .sort((a, b) => a.description.localeCompare(b.description))
+  }, [extData])
+
+  // Fetch report
+  const fetchReport = useCallback(async () => {
+    if (isMockActive && mockReport) {
+      setReport(mockReport)
+      setIsLoading(false)
+      return
+    }
+
+    setIsLoading(true)
+    setError(null)
+
+    try {
+      const params = new URLSearchParams({ year: String(year), month: String(month) })
+      const res = await fetch(`/api/extensions/export/intrastat/report?${params}`)
+      if (!res.ok) {
+        const json = await res.json()
+        setError(json.error || 'Kunde inte generera rapporten')
+        setReport(null)
+        return
+      }
+      const json = await res.json()
+      setReport(json.data)
+    } catch {
+      setError('Nätverksfel')
+      setReport(null)
+    } finally {
+      setIsLoading(false)
+    }
+  }, [year, month, isMockActive, mockReport])
+
+  useEffect(() => {
+    fetchReport()
+  }, [fetchReport])
+
+  const handleMockImport = useCallback(async (data: ReportData, meta: { source: 'csv' | 'json'; fileName: string; rowCount: number }) => {
+    await saveMockData(data, meta)
+    setReport(data)
+  }, [saveMockData])
+
+  const handleMockClear = useCallback(async () => {
+    await clearMockData()
+    setReport(null)
+    setIsLoading(true)
+    try {
+      const params = new URLSearchParams({ year: String(year), month: String(month) })
+      const res = await fetch(`/api/extensions/export/intrastat/report?${params}`)
+      if (res.ok) {
+        const json = await res.json()
+        setReport(json.data)
+      }
+    } catch { /* ignore */ }
+    setIsLoading(false)
+  }, [clearMockData, year, month])
+
+  // Product CRUD handlers
+  const openNewProduct = () => {
+    setEditingProduct(null)
+    setProductForm(EMPTY_PRODUCT)
+    setProductDialogOpen(true)
+  }
+
+  const openEditProduct = (productId: string) => {
+    const product = products.find(p => p.productId === productId)
+    if (!product) return
+    setEditingProduct(productId)
+    setProductForm({
+      productId,
+      description: product.description,
+      cnCode: product.cn_code || '',
+      netWeightKg: product.net_weight_kg !== null ? String(product.net_weight_kg) : '',
+      countryOfOrigin: product.country_of_origin,
+    })
+    setProductDialogOpen(true)
+  }
+
+  const saveProduct = async () => {
+    const id = editingProduct || productForm.productId.trim()
+    if (!id) return
+
+    await save(`product:${id}`, {
+      description: productForm.description.trim(),
+      cn_code: productForm.cnCode.trim() || null,
+      net_weight_kg: productForm.netWeightKg ? parseFloat(productForm.netWeightKg) : null,
+      country_of_origin: productForm.countryOfOrigin || 'SE',
+    })
+
+    setProductDialogOpen(false)
+    // Refresh report to pick up new product metadata
+    fetchReport()
+  }
+
+  const deleteProduct = async (productId: string) => {
+    await remove(`product:${productId}`)
+    setDeleteConfirm(null)
+    fetchReport()
+  }
+
+  // Download handler
+  const handleDownload = async () => {
+    setDownloading(true)
+    try {
+      const params = new URLSearchParams({ year: String(year), month: String(month) })
+      const res = await fetch(`/api/extensions/export/intrastat/download?${params}`)
+      if (!res.ok) {
+        setError('Kunde inte ladda ner filen')
+        return
+      }
+      const blob = await res.blob()
+      const disposition = res.headers.get('Content-Disposition') || ''
+      const match = disposition.match(/filename="(.+)"/)
+      const filename = match ? match[1] : `INTRASTAT_${year}-${String(month).padStart(2, '0')}.csv`
+
+      const url = URL.createObjectURL(blob)
+      const a = document.createElement('a')
+      a.href = url
+      a.download = filename
+      document.body.appendChild(a)
+      a.click()
+      document.body.removeChild(a)
+      URL.revokeObjectURL(url)
+    } catch {
+      setError('Kunde inte ladda ner filen')
+    } finally {
+      setDownloading(false)
+    }
+  }
+
+  const errorCount = report?.warnings.filter(w => w.severity === 'error').length ?? 0
+  const warningCount = report?.warnings.filter(w => w.severity === 'warning').length ?? 0
+
+  if ((isLoading || productsLoading || mockLoading) && !report) {
+    return <ExtensionLoadingSkeleton />
+  }
+
+  return (
+    <div className="space-y-6">
+      {/* ── Period Selector ─────────────────────────────────── */}
+      <div className="flex flex-wrap items-end gap-3">
+        <div className="space-y-1.5">
+          <label className="text-xs font-medium text-muted-foreground">År</label>
+          <Select value={String(year)} onValueChange={v => setYear(parseInt(v, 10))}>
+            <SelectTrigger className="w-[100px]"><SelectValue /></SelectTrigger>
+            <SelectContent>
+              {years.map(y => <SelectItem key={y} value={String(y)}>{y}</SelectItem>)}
+            </SelectContent>
+          </Select>
+        </div>
+        <div className="space-y-1.5">
+          <label className="text-xs font-medium text-muted-foreground">Månad</label>
+          <Select value={String(month)} onValueChange={v => setMonth(parseInt(v, 10))}>
+            <SelectTrigger className="w-[150px]"><SelectValue /></SelectTrigger>
+            <SelectContent>
+              {MONTHS.map((name, i) => <SelectItem key={i + 1} value={String(i + 1)}>{name}</SelectItem>)}
+            </SelectContent>
+          </Select>
+        </div>
+        <div className="flex gap-2 ml-auto">
+          <Button
+            variant="outline" size="sm"
+            onClick={() => setImportDialogOpen(true)}
+          >
+            <FlaskConical className="h-4 w-4 mr-1.5" />
+            Importera testdata
+          </Button>
+          <Button
+            variant="outline" size="sm"
+            onClick={handleDownload}
+            disabled={downloading || !report || report.lines.length === 0}
+          >
+            <FileSpreadsheet className="h-4 w-4 mr-1.5" />
+            {downloading ? 'Laddar...' : 'IDEP.web CSV'}
+          </Button>
+        </div>
+      </div>
+
+      {/* ── Mock Data Banner ──────────────────────────────── */}
+      {isMockActive && (
+        <MockDataBanner
+          importedAt={importedAt}
+          onClear={handleMockClear}
+          onReplace={() => setImportDialogOpen(true)}
+        />
+      )}
+
+      {error && (
+        <Card className="border-destructive/50 bg-destructive/5">
+          <CardContent className="pt-6">
+            <p className="text-sm text-destructive">{error}</p>
+          </CardContent>
+        </Card>
+      )}
+
+      {report && (
+        <>
+          {/* ── Threshold Progress ───────────────────────────── */}
+          <Card>
+            <CardContent className="pt-6">
+              <div className="flex items-center justify-between mb-2">
+                <p className="text-sm font-medium">Tröskelvärde Intrastat (utförsel)</p>
+                <Badge variant={report.thresholdStatus.isObligated ? 'destructive' : 'outline'}>
+                  {report.thresholdStatus.isObligated ? 'Obligatorisk rapportering' : 'Frivillig rapportering'}
+                </Badge>
+              </div>
+              <Progress
+                value={Math.min(report.thresholdStatus.percentageUsed, 100)}
+                className="h-3"
+              />
+              <div className="flex items-center justify-between mt-2 text-xs text-muted-foreground">
+                <span>
+                  Ackumulerat (12 mån): {formatSEK(report.thresholdStatus.cumulativeValue)} SEK
+                </span>
+                <span>
+                  {report.thresholdStatus.percentageUsed}% av {formatSEK(report.thresholdStatus.threshold)} SEK
+                </span>
+              </div>
+            </CardContent>
+          </Card>
+
+          {/* ── KPI Row ──────────────────────────────────────── */}
+          <div className="grid grid-cols-1 sm:grid-cols-3 gap-4">
+            <Card>
+              <CardContent className="pt-6">
+                <p className="text-sm text-muted-foreground">Fakturerat värde</p>
+                <p className="text-2xl font-semibold tabular-nums mt-1">{formatSEK(report.totals.invoicedValue)}</p>
+                <p className="text-xs text-muted-foreground mt-0.5">SEK</p>
+              </CardContent>
+            </Card>
+            <Card>
+              <CardContent className="pt-6">
+                <p className="text-sm text-muted-foreground">Nettovikt</p>
+                <p className="text-2xl font-semibold tabular-nums mt-1">{report.totals.netMass.toLocaleString('sv-SE')}</p>
+                <p className="text-xs text-muted-foreground mt-0.5">kg</p>
+              </CardContent>
+            </Card>
+            <Card>
+              <CardContent className="pt-6">
+                <p className="text-sm text-muted-foreground">Deklarationsrader</p>
+                <p className="text-2xl font-semibold tabular-nums mt-1">{report.totals.lineCount}</p>
+                <p className="text-xs text-muted-foreground mt-0.5">{report.invoiceCount} fakturor</p>
+              </CardContent>
+            </Card>
+          </div>
+
+          {/* ── Product Registry ─────────────────────────────── */}
+          <Card>
+            <CardHeader className="pb-3">
+              <div className="flex items-center justify-between">
+                <CardTitle className="text-base flex items-center gap-2">
+                  <Package className="h-4 w-4" />
+                  Produktregister
+                </CardTitle>
+                <Button variant="outline" size="sm" onClick={openNewProduct}>
+                  <Plus className="h-4 w-4 mr-1" />
+                  Lägg till
+                </Button>
+              </div>
+            </CardHeader>
+            <CardContent>
+              {products.length === 0 ? (
+                <p className="text-sm text-muted-foreground py-6 text-center">
+                  Inga produkter registrerade. Lägg till produkter med CN-kod och vikt för att generera Intrastat-deklarationer.
+                </p>
+              ) : (
+                <div className="overflow-x-auto">
+                  <Table>
+                    <TableHeader>
+                      <TableRow>
+                        <TableHead>Produkt</TableHead>
+                        <TableHead>CN-kod</TableHead>
+                        <TableHead className="text-right">Vikt (kg)</TableHead>
+                        <TableHead>Ursprung</TableHead>
+                        <TableHead className="w-20" />
+                      </TableRow>
+                    </TableHeader>
+                    <TableBody>
+                      {products.map(p => (
+                        <TableRow key={p.productId}>
+                          <TableCell className="text-sm">
+                            <div>
+                              <span className="font-medium">{p.description || p.productId}</span>
+                              {p.productId !== p.description && (
+                                <span className="text-xs text-muted-foreground ml-1">({p.productId})</span>
+                              )}
+                            </div>
+                          </TableCell>
+                          <TableCell>
+                            {p.cn_code ? (
+                              <Badge variant="outline" className="font-mono text-xs">{p.cn_code}</Badge>
+                            ) : (
+                              <span className="text-destructive text-xs flex items-center gap-1">
+                                <AlertTriangle className="h-3 w-3" /> Saknas
+                              </span>
+                            )}
+                          </TableCell>
+                          <TableCell className="text-right font-mono text-sm tabular-nums">
+                            {p.net_weight_kg !== null
+                              ? String(p.net_weight_kg)
+                              : <span className="text-muted-foreground">—</span>
+                            }
+                          </TableCell>
+                          <TableCell>
+                            <Badge variant="outline" className="text-xs">
+                              {p.country_of_origin}
+                            </Badge>
+                          </TableCell>
+                          <TableCell>
+                            <div className="flex gap-1 justify-end">
+                              <Button variant="ghost" size="sm" onClick={() => openEditProduct(p.productId)}>
+                                <Pencil className="h-3.5 w-3.5" />
+                              </Button>
+                              <Button variant="ghost" size="sm" onClick={() => setDeleteConfirm(p.productId)}>
+                                <Trash2 className="h-3.5 w-3.5 text-destructive" />
+                              </Button>
+                            </div>
+                          </TableCell>
+                        </TableRow>
+                      ))}
+                    </TableBody>
+                  </Table>
+                </div>
+              )}
+            </CardContent>
+          </Card>
+
+          {/* ── Declaration Table ─────────────────────────────── */}
+          <Card>
+            <CardHeader className="pb-3">
+              <CardTitle className="text-base">
+                Deklaration {MONTHS[month - 1]} {year}
+              </CardTitle>
+            </CardHeader>
+            <CardContent>
+              {report.lines.length === 0 ? (
+                <p className="text-sm text-muted-foreground py-6 text-center">
+                  Inga EU-varuförsäljningar hittades för perioden.
+                </p>
+              ) : (
+                <div className="overflow-x-auto">
+                  <Table>
+                    <TableHeader>
+                      <TableRow>
+                        <TableHead>CN-kod</TableHead>
+                        <TableHead>Land</TableHead>
+                        <TableHead>Urspr.</TableHead>
+                        <TableHead className="text-right">Värde (SEK)</TableHead>
+                        <TableHead className="text-right">Vikt (kg)</TableHead>
+                        <TableHead>Partner-VAT</TableHead>
+                      </TableRow>
+                    </TableHeader>
+                    <TableBody>
+                      {report.lines.map((line, i) => (
+                        <TableRow key={i}>
+                          <TableCell>
+                            <Badge
+                              variant={line.cnCode === '00000000' ? 'destructive' : 'outline'}
+                              className="font-mono text-xs"
+                            >
+                              {line.cnCode}
+                            </Badge>
+                          </TableCell>
+                          <TableCell>
+                            <Badge variant="outline" className="text-xs">{line.partnerCountry}</Badge>
+                          </TableCell>
+                          <TableCell className="text-xs">{line.countryOfOrigin}</TableCell>
+                          <TableCell className="text-right font-mono text-sm tabular-nums">
+                            {formatSEK(line.invoicedValue)}
+                          </TableCell>
+                          <TableCell className="text-right font-mono text-sm tabular-nums">
+                            {line.netMass > 0 ? line.netMass.toLocaleString('sv-SE') : '—'}
+                          </TableCell>
+                          <TableCell className="font-mono text-xs">{line.partnerVatId || '—'}</TableCell>
+                        </TableRow>
+                      ))}
+                      <TableRow className="border-t-2 font-medium">
+                        <TableCell colSpan={3} className="text-sm">Summa</TableCell>
+                        <TableCell className="text-right font-mono text-sm tabular-nums">
+                          {formatSEK(report.totals.invoicedValue)}
+                        </TableCell>
+                        <TableCell className="text-right font-mono text-sm tabular-nums">
+                          {report.totals.netMass.toLocaleString('sv-SE')}
+                        </TableCell>
+                        <TableCell />
+                      </TableRow>
+                    </TableBody>
+                  </Table>
+                </div>
+              )}
+            </CardContent>
+          </Card>
+
+          {/* ── Warnings ─────────────────────────────────────── */}
+          {report.warnings.length > 0 && (
+            <Card className={cn('border-l-4', errorCount > 0 ? 'border-l-destructive' : 'border-l-warning')}>
+              <CardContent className="pt-6">
+                <button className="flex items-center gap-2 w-full text-left" onClick={() => setWarningsExpanded(!warningsExpanded)}>
+                  <AlertTriangle className={cn('h-4 w-4 shrink-0', errorCount > 0 ? 'text-destructive' : 'text-warning-foreground')} />
+                  <span className="text-sm font-medium flex-1">
+                    {errorCount > 0 && <span className="text-destructive">{errorCount} fel</span>}
+                    {errorCount > 0 && warningCount > 0 && ', '}
+                    {warningCount > 0 && <span className="text-warning-foreground">{warningCount} varningar</span>}
+                  </span>
+                  {warningsExpanded ? <ChevronUp className="h-4 w-4 text-muted-foreground" /> : <ChevronDown className="h-4 w-4 text-muted-foreground" />}
+                </button>
+                {warningsExpanded && (
+                  <div className="mt-4 space-y-2">
+                    {report.warnings.map((w, i) => (
+                      <div key={i} className={cn('flex items-start gap-2 text-sm py-2 px-3 rounded-md', w.severity === 'error' ? 'bg-destructive/5 text-destructive' : 'bg-warning/10 text-warning-foreground')}>
+                        <AlertTriangle className="h-3.5 w-3.5 mt-0.5 shrink-0" />
+                        <span>{w.message}</span>
+                      </div>
+                    ))}
+                  </div>
+                )}
+              </CardContent>
+            </Card>
+          )}
+
+          {/* ── Deadline Footer ───────────────────────────────── */}
+          <div className="flex items-center gap-2 text-xs text-muted-foreground px-1">
+            <Clock className="h-3.5 w-3.5" />
+            <span>
+              Deadline: 10:e arbetsdagen efter redovisningsperiodens slut
+            </span>
+          </div>
+        </>
+      )}
+
+      {/* ── Mock Data Import Dialog ───────────────────────── */}
+      <MockDataImportDialog<ReportData>
+        open={importDialogOpen}
+        onOpenChange={setImportDialogOpen}
+        csvFields={MOCK_CSV_FIELDS}
+        parseCsvRows={parseMockCsvRows}
+        validateReport={validateMockReport}
+        templateCsvContent={MOCK_CSV_TEMPLATE}
+        templateFileName="intrastat-template.csv"
+        onImport={handleMockImport}
+      />
+
+      {/* ── Product Dialog ────────────────────────────────────── */}
+      <Dialog open={productDialogOpen} onOpenChange={setProductDialogOpen}>
+        <DialogContent>
+          <DialogHeader>
+            <DialogTitle>{editingProduct ? 'Redigera produkt' : 'Lägg till produkt'}</DialogTitle>
+          </DialogHeader>
+          <div className="space-y-4">
+            {!editingProduct && (
+              <div className="space-y-1.5">
+                <Label htmlFor="productId">Produkt-ID (SKU)</Label>
+                <Input
+                  id="productId"
+                  value={productForm.productId}
+                  onChange={e => setProductForm(f => ({ ...f, productId: e.target.value }))}
+                  placeholder="T.ex. STALBALK-M8"
+                />
+              </div>
+            )}
+            <div className="space-y-1.5">
+              <Label htmlFor="description">Beskrivning</Label>
+              <Input
+                id="description"
+                value={productForm.description}
+                onChange={e => setProductForm(f => ({ ...f, description: e.target.value }))}
+                placeholder="T.ex. Stålbalk M8 200mm"
+              />
+            </div>
+            <div className="space-y-1.5">
+              <Label htmlFor="cnCode">CN-kod (8 siffror)</Label>
+              <Input
+                id="cnCode"
+                value={productForm.cnCode}
+                onChange={e => setProductForm(f => ({ ...f, cnCode: e.target.value.replace(/\D/g, '').slice(0, 8) }))}
+                placeholder="T.ex. 72163100"
+                maxLength={8}
+                className="font-mono"
+              />
+            </div>
+            <div className="grid grid-cols-2 gap-3">
+              <div className="space-y-1.5">
+                <Label htmlFor="weight">Nettovikt per enhet (kg)</Label>
+                <Input
+                  id="weight"
+                  type="number"
+                  step="0.001"
+                  value={productForm.netWeightKg}
+                  onChange={e => setProductForm(f => ({ ...f, netWeightKg: e.target.value }))}
+                  placeholder="45.5"
+                />
+              </div>
+              <div className="space-y-1.5">
+                <Label htmlFor="origin">Ursprungsland</Label>
+                <Input
+                  id="origin"
+                  value={productForm.countryOfOrigin}
+                  onChange={e => setProductForm(f => ({ ...f, countryOfOrigin: e.target.value.toUpperCase().slice(0, 2) }))}
+                  placeholder="SE"
+                  maxLength={2}
+                />
+              </div>
+            </div>
+          </div>
+          <DialogFooter>
+            <Button variant="outline" onClick={() => setProductDialogOpen(false)}>Avbryt</Button>
+            <Button
+              onClick={saveProduct}
+              disabled={!editingProduct && !productForm.productId.trim()}
+            >
+              {editingProduct ? 'Spara' : 'Lägg till'}
+            </Button>
+          </DialogFooter>
+        </DialogContent>
+      </Dialog>
+
+      {/* ── Delete Confirmation ───────────────────────────────── */}
+      <Dialog open={deleteConfirm !== null} onOpenChange={() => setDeleteConfirm(null)}>
+        <DialogContent>
+          <DialogHeader>
+            <DialogTitle>Ta bort produkt?</DialogTitle>
+          </DialogHeader>
+          <p className="text-sm text-muted-foreground">
+            Är du säker på att du vill ta bort produkten &ldquo;{deleteConfirm}&rdquo;? Denna åtgärd kan inte ångras.
+          </p>
+          <DialogFooter>
+            <Button variant="outline" onClick={() => setDeleteConfirm(null)}>Avbryt</Button>
+            <Button variant="destructive" onClick={() => deleteConfirm && deleteProduct(deleteConfirm)}>
+              Ta bort
+            </Button>
+          </DialogFooter>
+        </DialogContent>
+      </Dialog>
+    </div>
+  )
+}

components/extensions/export/VatMonitorWorkspace.tsx

@@ -0,0 +1,656 @@
+'use client'
+
+import { useState, useEffect, useMemo, useCallback } from 'react'
+import type { WorkspaceComponentProps } from '@/lib/extensions/workspace-registry'
+import { useMockData } from '@/lib/extensions/use-mock-data'
+import ExtensionLoadingSkeleton from '@/components/extensions/shared/ExtensionLoadingSkeleton'
+import MockDataBanner from '@/components/extensions/shared/MockDataBanner'
+import MockDataImportDialog from '@/components/extensions/shared/MockDataImportDialog'
+import type { CsvFieldDef } from '@/components/extensions/shared/MockDataImportDialog'
+import KPICard from '@/components/extensions/shared/KPICard'
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card'
+import { Badge } from '@/components/ui/badge'
+import { Button } from '@/components/ui/button'
+import {
+  Select, SelectContent, SelectItem, SelectTrigger, SelectValue,
+} from '@/components/ui/select'
+import {
+  Table, TableBody, TableCell, TableHead, TableHeader, TableRow,
+} from '@/components/ui/table'
+import {
+  AlertTriangle, CheckCircle2, ChevronDown, ChevronUp,
+  ArrowUp, ArrowDown, Minus, BarChart3, FlaskConical,
+} from 'lucide-react'
+import { cn } from '@/lib/utils'
+
+// ── Types ─────────────────────────────────────────────────────
+
+interface VatBoxData {
+  boxNumber: string
+  label: string
+  amount: number
+  accounts: string[]
+}
+
+interface RevenueBreakdown {
+  domestic: { amount: number; percentage: number }
+  euGoods: { amount: number; percentage: number }
+  euServices: { amount: number; percentage: number }
+  exportGoods: { amount: number; percentage: number }
+  exportServices: { amount: number; percentage: number }
+  triangular: { amount: number; percentage: number }
+  totalRevenue: number
+}
+
+interface PeriodDelta {
+  current: number
+  previous: number
+  change: number
+  changePercent: number | null
+}
+
+interface PeriodComparison {
+  domestic: PeriodDelta
+  euGoods: PeriodDelta
+  euServices: PeriodDelta
+  exportGoods: PeriodDelta
+  exportServices: PeriodDelta
+  triangular: PeriodDelta
+  totalRevenue: PeriodDelta
+  netVat: PeriodDelta
+}
+
+interface VatMonitorWarning {
+  type: string
+  severity: 'error' | 'warning'
+  invoiceId?: string
+  invoiceNumber?: string
+  customerName?: string
+  message: string
+}
+
+interface ReportData {
+  period: { year: number; month?: number; quarter?: number }
+  boxes: VatBoxData[]
+  revenueBreakdown: RevenueBreakdown
+  vatSummary: {
+    outputVat25: number
+    outputVat12: number
+    outputVat6: number
+    totalOutputVat: number
+    inputVat: number
+    netVat: number
+    isRefund: boolean
+  }
+  warnings: VatMonitorWarning[]
+  comparison: PeriodComparison | null
+}
+
+// ── Helpers ───────────────────────────────────────────────────
+
+function formatSEK(amount: number): string {
+  return Math.round(amount).toLocaleString('sv-SE')
+}
+
+const MONTHS = [
+  'Januari', 'Februari', 'Mars', 'April', 'Maj', 'Juni',
+  'Juli', 'Augusti', 'September', 'Oktober', 'November', 'December',
+]
+
+const QUARTERS = ['Q1 (jan–mar)', 'Q2 (apr–jun)', 'Q3 (jul–sep)', 'Q4 (okt–dec)']
+
+function currentYear(): number {
+  return new Date().getFullYear()
+}
+
+function currentMonth(): number {
+  return new Date().getMonth() + 1
+}
+
+function currentQuarter(): number {
+  return Math.ceil(currentMonth() / 3)
+}
+
+// Revenue breakdown cards config
+const REVENUE_CARDS: { key: keyof Omit<RevenueBreakdown, 'totalRevenue'>; label: string; compKey: keyof PeriodComparison }[] = [
+  { key: 'domestic', label: 'Inrikes', compKey: 'domestic' },
+  { key: 'euGoods', label: 'EU varor', compKey: 'euGoods' },
+  { key: 'euServices', label: 'EU tjänster', compKey: 'euServices' },
+  { key: 'exportGoods', label: 'Export varor', compKey: 'exportGoods' },
+  { key: 'exportServices', label: 'Export tjänster', compKey: 'exportServices' },
+  { key: 'triangular', label: 'Trepartshandel', compKey: 'triangular' },
+]
+
+// Box display order (only show relevant ones)
+const DISPLAY_BOX_ORDER = ['05', '10', '11', '12', '35', '36', '38', '39', '40', '48', '49']
+
+// ── Mock Data Config ──────────────────────────────────────────
+
+const MOCK_CSV_FIELDS: CsvFieldDef[] = [
+  { key: 'boxNumber', label: 'Ruta', required: true },
+  { key: 'label', label: 'Beskrivning', required: true },
+  { key: 'amount', label: 'Belopp (SEK)', required: true },
+  { key: 'accounts', label: 'Konton (kommaseparerade)' },
+]
+
+const MOCK_CSV_TEMPLATE = `boxNumber;label;amount;accounts
+05;Momspliktiga intäkter;500000;3001,3002,3003
+10;Utgående moms 25%;100000;2611
+11;Utgående moms 12%;6000;2621
+12;Utgående moms 6%;3000;2631
+35;Varuförsäljning EU;75000;3305
+36;Tjänsteförsäljning EU;45000;3308
+38;Exportförsäljning;30000;3305
+39;Omvänd skattskyldighet;20000;
+40;Inköp varor EU;60000;
+48;Ingående moms;65000;2641
+49;Moms att betala;44000;`
+
+function parseMockCsvRows(rows: Record<string, string>[]): ReportData {
+  const boxes: VatBoxData[] = rows.map(r => ({
+    boxNumber: r.boxNumber || '',
+    label: r.label || '',
+    amount: parseFloat(r.amount || '0') || 0,
+    accounts: r.accounts ? r.accounts.split(',').map(a => a.trim()) : [],
+  }))
+
+  // Derive revenue breakdown from box values
+  const getBox = (num: string) => boxes.find(b => b.boxNumber === num)?.amount || 0
+  const domestic = getBox('05')
+  const euGoods = getBox('35')
+  const euServices = getBox('36')
+  const exportGoods = getBox('38')
+  const exportServices = 0
+  const triangular = getBox('39')
+  const totalRevenue = domestic + euGoods + euServices + exportGoods + exportServices + triangular
+
+  const revenueBreakdown: RevenueBreakdown = {
+    domestic: { amount: domestic, percentage: totalRevenue > 0 ? Math.round(domestic / totalRevenue * 100) : 0 },
+    euGoods: { amount: euGoods, percentage: totalRevenue > 0 ? Math.round(euGoods / totalRevenue * 100) : 0 },
+    euServices: { amount: euServices, percentage: totalRevenue > 0 ? Math.round(euServices / totalRevenue * 100) : 0 },
+    exportGoods: { amount: exportGoods, percentage: totalRevenue > 0 ? Math.round(exportGoods / totalRevenue * 100) : 0 },
+    exportServices: { amount: exportServices, percentage: 0 },
+    triangular: { amount: triangular, percentage: totalRevenue > 0 ? Math.round(triangular / totalRevenue * 100) : 0 },
+    totalRevenue,
+  }
+
+  const outputVat25 = getBox('10')
+  const outputVat12 = getBox('11')
+  const outputVat6 = getBox('12')
+  const inputVat = getBox('48')
+  const netVat = getBox('49')
+
+  return {
+    period: { year: new Date().getFullYear(), month: new Date().getMonth() + 1 },
+    boxes,
+    revenueBreakdown,
+    vatSummary: {
+      outputVat25,
+      outputVat12,
+      outputVat6,
+      totalOutputVat: outputVat25 + outputVat12 + outputVat6,
+      inputVat,
+      netVat,
+      isRefund: netVat < 0,
+    },
+    warnings: [],
+    comparison: null,
+  }
+}
+
+function validateMockReport(data: unknown): { valid: boolean; error?: string } {
+  if (!data || typeof data !== 'object') return { valid: false, error: 'Data måste vara ett objekt' }
+  const obj = data as Record<string, unknown>
+  if (!Array.isArray(obj.boxes)) return { valid: false, error: 'Fältet "boxes" saknas eller är inte en array' }
+  if (!obj.revenueBreakdown || typeof obj.revenueBreakdown !== 'object') {
+    return { valid: false, error: 'Fältet "revenueBreakdown" saknas' }
+  }
+  if (!obj.vatSummary || typeof obj.vatSummary !== 'object') {
+    return { valid: false, error: 'Fältet "vatSummary" saknas' }
+  }
+  return { valid: true }
+}
+
+// ── Component ─────────────────────────────────────────────────
+
+export default function VatMonitorWorkspace({ userId }: WorkspaceComponentProps) {
+  void userId
+
+  // Mock data
+  const { mockReport, isMockActive, isLoading: mockLoading, importedAt, saveMockData, clearMockData } = useMockData<ReportData>('export', 'vat-monitor')
+  const [importDialogOpen, setImportDialogOpen] = useState(false)
+
+  const [year, setYear] = useState(currentYear())
+  const [periodType, setPeriodType] = useState<'monthly' | 'quarterly'>('monthly')
+  const [month, setMonth] = useState(currentMonth())
+  const [quarter, setQuarter] = useState(currentQuarter())
+  const [compareEnabled, setCompareEnabled] = useState(true)
+
+  const [report, setReport] = useState<ReportData | null>(null)
+  const [isLoading, setIsLoading] = useState(true)
+  const [error, setError] = useState<string | null>(null)
+
+  const [warningsExpanded, setWarningsExpanded] = useState(false)
+
+  const years = useMemo(() => {
+    const cy = currentYear()
+    return [cy, cy - 1, cy - 2]
+  }, [])
+
+  const fetchReport = useCallback(async () => {
+    if (isMockActive && mockReport) {
+      setReport(mockReport)
+      setIsLoading(false)
+      return
+    }
+
+    setIsLoading(true)
+    setError(null)
+
+    const params = new URLSearchParams({ year: String(year) })
+    if (periodType === 'monthly') {
+      params.set('month', String(month))
+    } else {
+      params.set('quarter', String(quarter))
+    }
+    if (compareEnabled) {
+      params.set('compare', 'previous')
+    }
+
+    try {
+      const res = await fetch(`/api/extensions/export/vat-monitor/report?${params}`)
+      if (!res.ok) {
+        const json = await res.json()
+        setError(json.error || 'Kunde inte generera rapporten')
+        setReport(null)
+        return
+      }
+      const json = await res.json()
+      setReport(json.data)
+    } catch {
+      setError('Nätverksfel — kunde inte hämta rapporten')
+      setReport(null)
+    } finally {
+      setIsLoading(false)
+    }
+  }, [year, month, quarter, periodType, compareEnabled, isMockActive, mockReport])
+
+  useEffect(() => {
+    fetchReport()
+  }, [fetchReport])
+
+  const handleMockImport = useCallback(async (data: ReportData, meta: { source: 'csv' | 'json'; fileName: string; rowCount: number }) => {
+    await saveMockData(data, meta)
+    setReport(data)
+  }, [saveMockData])
+
+  const handleMockClear = useCallback(async () => {
+    await clearMockData()
+    setReport(null)
+    setIsLoading(true)
+    setError(null)
+    const params = new URLSearchParams({ year: String(year) })
+    if (periodType === 'monthly') {
+      params.set('month', String(month))
+    } else {
+      params.set('quarter', String(quarter))
+    }
+    if (compareEnabled) {
+      params.set('compare', 'previous')
+    }
+    try {
+      const res = await fetch(`/api/extensions/export/vat-monitor/report?${params}`)
+      if (res.ok) {
+        const json = await res.json()
+        setReport(json.data)
+      }
+    } catch { /* ignore */ }
+    setIsLoading(false)
+  }, [clearMockData, year, month, quarter, periodType, compareEnabled])
+
+  const errorCount = report?.warnings.filter(w => w.severity === 'error').length ?? 0
+  const warningCount = report?.warnings.filter(w => w.severity === 'warning').length ?? 0
+
+  // Filter boxes to only show ones in display order that have data or are always shown
+  const displayBoxes = useMemo(() => {
+    if (!report) return []
+    const boxMap = new Map(report.boxes.map(b => [b.boxNumber, b]))
+    return DISPLAY_BOX_ORDER
+      .map(num => boxMap.get(num))
+      .filter((b): b is VatBoxData => b !== undefined)
+  }, [report])
+
+  if ((isLoading || mockLoading) && !report) {
+    return <ExtensionLoadingSkeleton />
+  }
+
+  return (
+    <div className="space-y-6">
+      {/* ── Period Selector ─────────────────────────────────── */}
+      <div className="flex flex-wrap items-end gap-3">
+        <div className="space-y-1.5">
+          <label className="text-xs font-medium text-muted-foreground">År</label>
+          <Select value={String(year)} onValueChange={v => setYear(parseInt(v, 10))}>
+            <SelectTrigger className="w-[100px]">
+              <SelectValue />
+            </SelectTrigger>
+            <SelectContent>
+              {years.map(y => (
+                <SelectItem key={y} value={String(y)}>{y}</SelectItem>
+              ))}
+            </SelectContent>
+          </Select>
+        </div>
+
+        <div className="space-y-1.5">
+          <label className="text-xs font-medium text-muted-foreground">Periodtyp</label>
+          <Select value={periodType} onValueChange={v => setPeriodType(v as 'monthly' | 'quarterly')}>
+            <SelectTrigger className="w-[130px]">
+              <SelectValue />
+            </SelectTrigger>
+            <SelectContent>
+              <SelectItem value="monthly">Månad</SelectItem>
+              <SelectItem value="quarterly">Kvartal</SelectItem>
+            </SelectContent>
+          </Select>
+        </div>
+
+        <div className="space-y-1.5">
+          <label className="text-xs font-medium text-muted-foreground">
+            {periodType === 'monthly' ? 'Månad' : 'Kvartal'}
+          </label>
+          {periodType === 'monthly' ? (
+            <Select value={String(month)} onValueChange={v => setMonth(parseInt(v, 10))}>
+              <SelectTrigger className="w-[150px]">
+                <SelectValue />
+              </SelectTrigger>
+              <SelectContent>
+                {MONTHS.map((name, i) => (
+                  <SelectItem key={i + 1} value={String(i + 1)}>{name}</SelectItem>
+                ))}
+              </SelectContent>
+            </Select>
+          ) : (
+            <Select value={String(quarter)} onValueChange={v => setQuarter(parseInt(v, 10))}>
+              <SelectTrigger className="w-[150px]">
+                <SelectValue />
+              </SelectTrigger>
+              <SelectContent>
+                {QUARTERS.map((name, i) => (
+                  <SelectItem key={i + 1} value={String(i + 1)}>{name}</SelectItem>
+                ))}
+              </SelectContent>
+            </Select>
+          )}
+        </div>
+
+        <div className="flex gap-2 ml-auto">
+          <Button
+            variant="outline"
+            size="sm"
+            onClick={() => setImportDialogOpen(true)}
+          >
+            <FlaskConical className="h-4 w-4 mr-1.5" />
+            Importera testdata
+          </Button>
+          <Button
+            variant={compareEnabled ? 'default' : 'outline'}
+            size="sm"
+            onClick={() => setCompareEnabled(!compareEnabled)}
+          >
+            <BarChart3 className="h-4 w-4 mr-1.5" />
+            {compareEnabled ? 'Jämförelse på' : 'Jämför perioder'}
+          </Button>
+        </div>
+      </div>
+
+      {/* ── Mock Data Banner ──────────────────────────────── */}
+      {isMockActive && (
+        <MockDataBanner
+          importedAt={importedAt}
+          onClear={handleMockClear}
+          onReplace={() => setImportDialogOpen(true)}
+        />
+      )}
+
+      {/* ── Error state ────────────────────────────────────── */}
+      {error && (
+        <Card className="border-destructive/50 bg-destructive/5">
+          <CardContent className="pt-6">
+            <p className="text-sm text-destructive">{error}</p>
+          </CardContent>
+        </Card>
+      )}
+
+      {report && (
+        <>
+          {/* ── Revenue Breakdown Cards ──────────────────────── */}
+          <div>
+            <h3 className="text-sm font-medium text-muted-foreground mb-3">Intäktsfördelning</h3>
+            <div className="grid grid-cols-2 sm:grid-cols-3 lg:grid-cols-6 gap-3">
+              {REVENUE_CARDS.map(({ key, label, compKey }) => {
+                const data = report.revenueBreakdown[key]
+                const delta = report.comparison?.[compKey]
+                return (
+                  <Card key={key} className={cn(data.amount === 0 && 'opacity-50')}>
+                    <CardContent className="pt-4 pb-3 px-4">
+                      <p className="text-xs text-muted-foreground truncate">{label}</p>
+                      <p className="text-lg font-semibold tabular-nums mt-0.5">
+                        {formatSEK(data.amount)}
+                      </p>
+                      <div className="flex items-center justify-between mt-1">
+                        <span className="text-xs text-muted-foreground">
+                          {data.percentage}%
+                        </span>
+                        {delta && <DeltaIndicator delta={delta} />}
+                      </div>
+                    </CardContent>
+                  </Card>
+                )
+              })}
+            </div>
+          </div>
+
+          {/* ── VAT Summary + Moms Box Table ─────────────────── */}
+          <div className="grid grid-cols-1 lg:grid-cols-3 gap-4">
+            {/* VAT Summary cards */}
+            <div className="space-y-3">
+              <h3 className="text-sm font-medium text-muted-foreground">Moms</h3>
+              <KPICard
+                label="Utgående moms"
+                value={formatSEK(report.vatSummary.totalOutputVat)}
+                suffix="SEK"
+              />
+              <KPICard
+                label="Ingående moms"
+                value={formatSEK(report.vatSummary.inputVat)}
+                suffix="SEK"
+              />
+              <Card className={cn(
+                report.vatSummary.isRefund ? 'border-green-200 bg-green-50/50 dark:border-green-900 dark:bg-green-950/30' : ''
+              )}>
+                <CardContent className="pt-6">
+                  <p className="text-sm text-muted-foreground">
+                    {report.vatSummary.isRefund ? 'Moms att få tillbaka' : 'Moms att betala'}
+                  </p>
+                  <div className="flex items-baseline gap-1 mt-1">
+                    <span className={cn(
+                      'text-2xl font-semibold tracking-tight',
+                      report.vatSummary.isRefund && 'text-green-700 dark:text-green-400'
+                    )}>
+                      {formatSEK(Math.abs(report.vatSummary.netVat))}
+                    </span>
+                    <span className="text-sm text-muted-foreground">SEK</span>
+                  </div>
+                  {report.comparison && (
+                    <div className="mt-1">
+                      <DeltaIndicator delta={report.comparison.netVat} invert />
+                    </div>
+                  )}
+                </CardContent>
+              </Card>
+            </div>
+
+            {/* Momsdeklaration preview table */}
+            <div className="lg:col-span-2">
+              <h3 className="text-sm font-medium text-muted-foreground mb-3">
+                Momsdeklaration (förhandsvisning)
+              </h3>
+              <Card>
+                <CardContent className="p-0">
+                  <Table>
+                    <TableHeader>
+                      <TableRow>
+                        <TableHead className="w-16">Ruta</TableHead>
+                        <TableHead>Beskrivning</TableHead>
+                        <TableHead className="text-right w-36">Belopp (SEK)</TableHead>
+                      </TableRow>
+                    </TableHeader>
+                    <TableBody>
+                      {displayBoxes.map(box => {
+                        const isNetVat = box.boxNumber === '49'
+                        const isInputVat = box.boxNumber === '48'
+                        return (
+                          <TableRow
+                            key={box.boxNumber}
+                            className={cn(isNetVat && 'font-medium border-t-2')}
+                          >
+                            <TableCell>
+                              <Badge
+                                variant={isNetVat ? 'default' : isInputVat ? 'secondary' : 'outline'}
+                                className="font-mono text-xs"
+                              >
+                                {box.boxNumber}
+                              </Badge>
+                            </TableCell>
+                            <TableCell className="text-sm">{box.label}</TableCell>
+                            <TableCell className="text-right font-mono text-sm tabular-nums">
+                              {formatSEK(box.amount)}
+                            </TableCell>
+                          </TableRow>
+                        )
+                      })}
+                      {displayBoxes.length === 0 && (
+                        <TableRow>
+                          <TableCell colSpan={3} className="text-center text-muted-foreground py-8">
+                            Ingen bokföringsdata för perioden.
+                          </TableCell>
+                        </TableRow>
+                      )}
+                    </TableBody>
+                  </Table>
+                </CardContent>
+              </Card>
+            </div>
+          </div>
+
+          {/* ── Warnings ─────────────────────────────────────── */}
+          {report.warnings.length > 0 && (
+            <Card className={cn(
+              'border-l-4',
+              errorCount > 0 ? 'border-l-destructive' : 'border-l-warning'
+            )}>
+              <CardContent className="pt-6">
+                <button
+                  className="flex items-center gap-2 w-full text-left"
+                  onClick={() => setWarningsExpanded(!warningsExpanded)}
+                >
+                  <AlertTriangle className={cn(
+                    'h-4 w-4 shrink-0',
+                    errorCount > 0 ? 'text-destructive' : 'text-warning-foreground'
+                  )} />
+                  <span className="text-sm font-medium flex-1">
+                    {errorCount > 0 && (
+                      <span className="text-destructive">{errorCount} fel</span>
+                    )}
+                    {errorCount > 0 && warningCount > 0 && ', '}
+                    {warningCount > 0 && (
+                      <span className="text-warning-foreground">{warningCount} varningar</span>
+                    )}
+                  </span>
+                  {warningsExpanded
+                    ? <ChevronUp className="h-4 w-4 text-muted-foreground" />
+                    : <ChevronDown className="h-4 w-4 text-muted-foreground" />
+                  }
+                </button>
+
+                {warningsExpanded && (
+                  <div className="mt-4 space-y-2">
+                    {report.warnings.map((w, i) => (
+                      <div
+                        key={i}
+                        className={cn(
+                          'flex items-start gap-2 text-sm py-2 px-3 rounded-md',
+                          w.severity === 'error'
+                            ? 'bg-destructive/5 text-destructive'
+                            : 'bg-warning/10 text-warning-foreground'
+                        )}
+                      >
+                        <AlertTriangle className="h-3.5 w-3.5 mt-0.5 shrink-0" />
+                        <span>{w.message}</span>
+                      </div>
+                    ))}
+                  </div>
+                )}
+              </CardContent>
+            </Card>
+          )}
+
+          {/* ── Total Revenue Footer ─────────────────────────── */}
+          <div className="flex items-center justify-between text-xs text-muted-foreground px-1">
+            <span>
+              Total omsättning: {formatSEK(report.revenueBreakdown.totalRevenue)} SEK
+            </span>
+            <span>
+              {report.period.year}
+              {report.period.month !== undefined && `, ${MONTHS[report.period.month - 1]}`}
+              {report.period.quarter !== undefined && `, ${QUARTERS[report.period.quarter - 1]}`}
+            </span>
+          </div>
+        </>
+      )}
+
+      {/* ── Mock Data Import Dialog ───────────────────────── */}
+      <MockDataImportDialog<ReportData>
+        open={importDialogOpen}
+        onOpenChange={setImportDialogOpen}
+        csvFields={MOCK_CSV_FIELDS}
+        parseCsvRows={parseMockCsvRows}
+        validateReport={validateMockReport}
+        templateCsvContent={MOCK_CSV_TEMPLATE}
+        templateFileName="vat-monitor-template.csv"
+        onImport={handleMockImport}
+      />
+    </div>
+  )
+}
+
+// ── Sub-components ────────────────────────────────────────────
+
+function DeltaIndicator({ delta, invert = false }: { delta: PeriodDelta; invert?: boolean }) {
+  if (delta.changePercent === null || delta.change === 0) {
+    return (
+      <span className="inline-flex items-center gap-0.5 text-xs text-muted-foreground">
+        <Minus className="h-3 w-3" />
+      </span>
+    )
+  }
+
+  // For most metrics, positive = green (revenue growing)
+  // For netVat (invert=true), positive = red (paying more VAT)
+  const isPositive = delta.change > 0
+  const isGood = invert ? !isPositive : isPositive
+
+  return (
+    <span className={cn(
+      'inline-flex items-center gap-0.5 text-xs',
+      isGood ? 'text-green-600' : 'text-red-600'
+    )}>
+      {isPositive
+        ? <ArrowUp className="h-3 w-3" />
+        : <ArrowDown className="h-3 w-3" />
+      }
+      <span>{delta.changePercent > 0 ? '+' : ''}{delta.changePercent}%</span>
+    </span>
+  )
+}

components/extensions/shared/MockDataBanner.tsx

@@ -0,0 +1,49 @@
+'use client'
+
+import { Card, CardContent } from '@/components/ui/card'
+import { Button } from '@/components/ui/button'
+import { FlaskConical, X, Replace } from 'lucide-react'
+
+interface MockDataBannerProps {
+  importedAt: string | null
+  onClear: () => void
+  onReplace: () => void
+}
+
+export default function MockDataBanner({ importedAt, onClear, onReplace }: MockDataBannerProps) {
+  const formatted = importedAt
+    ? new Date(importedAt).toLocaleString('sv-SE', {
+        year: 'numeric', month: 'short', day: 'numeric',
+        hour: '2-digit', minute: '2-digit',
+      })
+    : null
+
+  return (
+    <Card className="border-l-4 border-l-amber-500 bg-amber-50/50 dark:bg-amber-950/20 dark:border-l-amber-400">
+      <CardContent className="pt-4 pb-4">
+        <div className="flex items-center gap-3">
+          <FlaskConical className="h-5 w-5 text-amber-600 dark:text-amber-400 shrink-0" />
+          <div className="flex-1 min-w-0">
+            <p className="text-sm font-medium text-amber-900 dark:text-amber-200">
+              Testdata aktivt
+            </p>
+            <p className="text-xs text-amber-700 dark:text-amber-400 mt-0.5">
+              Rapporten visar importerad testdata istället för bokföringsdata.
+              {formatted && <> Importerat {formatted}.</>}
+            </p>
+          </div>
+          <div className="flex gap-1.5 shrink-0">
+            <Button variant="outline" size="sm" onClick={onReplace} className="h-7 text-xs">
+              <Replace className="h-3.5 w-3.5 mr-1" />
+              Ersätt
+            </Button>
+            <Button variant="outline" size="sm" onClick={onClear} className="h-7 text-xs">
+              <X className="h-3.5 w-3.5 mr-1" />
+              Rensa
+            </Button>
+          </div>
+        </div>
+      </CardContent>
+    </Card>
+  )
+}

components/extensions/shared/MockDataImportDialog.tsx

@@ -0,0 +1,404 @@
+'use client'
+
+import { useState, useCallback, useRef } from 'react'
+import {
+  Dialog, DialogContent, DialogHeader, DialogTitle, DialogFooter,
+} from '@/components/ui/dialog'
+import { Button } from '@/components/ui/button'
+import { Label } from '@/components/ui/label'
+import {
+  Select, SelectContent, SelectItem, SelectTrigger, SelectValue,
+} from '@/components/ui/select'
+import {
+  Table, TableBody, TableCell, TableHead, TableHeader, TableRow,
+} from '@/components/ui/table'
+import {
+  Upload, FileJson, FileSpreadsheet, Download, AlertCircle, Check,
+} from 'lucide-react'
+import { cn } from '@/lib/utils'
+
+// ── Types ─────────────────────────────────────────────────────
+
+export interface CsvFieldDef {
+  key: string
+  label: string
+  required?: boolean
+}
+
+interface MockDataImportDialogProps<T> {
+  open: boolean
+  onOpenChange: (open: boolean) => void
+  csvFields: CsvFieldDef[]
+  defaultMappings?: Record<string, string>
+  parseCsvRows: (rows: Record<string, string>[]) => T
+  validateReport: (data: unknown) => { valid: boolean; error?: string }
+  templateCsvContent: string
+  templateFileName: string
+  onImport: (report: T, meta: { source: 'csv' | 'json'; fileName: string; rowCount: number }) => Promise<void>
+}
+
+function parseCsv(text: string): { headers: string[]; rows: string[][] } {
+  const lines = text.split(/\r?\n/).filter(line => line.trim())
+  if (lines.length === 0) return { headers: [], rows: [] }
+
+  const separator = lines[0].includes(';') ? ';' : ','
+  const headers = lines[0].split(separator).map(h => h.trim().replace(/^"(.*)"$/, '$1'))
+  const rows = lines.slice(1).map(line =>
+    line.split(separator).map(cell => cell.trim().replace(/^"(.*)"$/, '$1'))
+  )
+  return { headers, rows }
+}
+
+// ── Component ─────────────────────────────────────────────────
+
+type Step = 'upload' | 'map-csv' | 'preview-json' | 'importing'
+
+export default function MockDataImportDialog<T>({
+  open,
+  onOpenChange,
+  csvFields,
+  defaultMappings,
+  parseCsvRows,
+  validateReport,
+  templateCsvContent,
+  templateFileName,
+  onImport,
+}: MockDataImportDialogProps<T>) {
+  const [step, setStep] = useState<Step>('upload')
+  const [isDragging, setIsDragging] = useState(false)
+  const [error, setError] = useState<string | null>(null)
+  const fileInputRef = useRef<HTMLInputElement>(null)
+
+  // CSV state
+  const [csvHeaders, setCsvHeaders] = useState<string[]>([])
+  const [csvRows, setCsvRows] = useState<string[][]>([])
+  const [mappings, setMappings] = useState<Record<string, string>>({})
+  const [fileName, setFileName] = useState('')
+
+  // JSON state
+  const [jsonReport, setJsonReport] = useState<T | null>(null)
+  const [jsonSummary, setJsonSummary] = useState('')
+
+  const reset = useCallback(() => {
+    setStep('upload')
+    setError(null)
+    setCsvHeaders([])
+    setCsvRows([])
+    setMappings({})
+    setFileName('')
+    setJsonReport(null)
+    setJsonSummary('')
+    setIsDragging(false)
+  }, [])
+
+  const handleOpenChange = useCallback((open: boolean) => {
+    if (!open) reset()
+    onOpenChange(open)
+  }, [onOpenChange, reset])
+
+  const processFile = useCallback((file: File) => {
+    setError(null)
+    setFileName(file.name)
+
+    const reader = new FileReader()
+    reader.onload = (ev) => {
+      const text = ev.target?.result as string
+
+      if (file.name.endsWith('.json')) {
+        // JSON path
+        try {
+          const parsed = JSON.parse(text)
+          const validation = validateReport(parsed)
+          if (!validation.valid) {
+            setError(validation.error || 'Ogiltig JSON-struktur')
+            return
+          }
+          setJsonReport(parsed as T)
+
+          // Build summary
+          const keys = Object.keys(parsed)
+          const lines = Array.isArray(parsed.lines) ? parsed.lines.length
+            : Array.isArray(parsed.receivables) ? parsed.receivables.length
+            : Array.isArray(parsed.boxes) ? parsed.boxes.length
+            : null
+          setJsonSummary(
+            `${keys.length} fält` + (lines !== null ? `, ${lines} rader` : '')
+          )
+          setStep('preview-json')
+        } catch {
+          setError('Kunde inte tolka JSON-filen. Kontrollera formatet.')
+        }
+      } else {
+        // CSV path
+        const parsed = parseCsv(text)
+        if (parsed.headers.length === 0 || parsed.rows.length === 0) {
+          setError('Ingen data hittades i CSV-filen.')
+          return
+        }
+
+        setCsvHeaders(parsed.headers)
+        setCsvRows(parsed.rows)
+
+        // Auto-map columns
+        const autoMappings: Record<string, string> = {}
+        for (const field of csvFields) {
+          const defaultCol = defaultMappings?.[field.key]
+          if (defaultCol && parsed.headers.includes(defaultCol)) {
+            autoMappings[field.key] = defaultCol
+          } else {
+            const match = parsed.headers.find(
+              h => h.toLowerCase() === field.key.toLowerCase() ||
+                   h.toLowerCase() === field.label.toLowerCase()
+            )
+            if (match) autoMappings[field.key] = match
+          }
+        }
+        setMappings(autoMappings)
+        setStep('map-csv')
+      }
+    }
+    reader.readAsText(file)
+  }, [csvFields, defaultMappings, validateReport])
+
+  const handleDrop = useCallback((e: React.DragEvent) => {
+    e.preventDefault()
+    setIsDragging(false)
+    const file = e.dataTransfer.files[0]
+    if (file) processFile(file)
+  }, [processFile])
+
+  const handleFileInput = useCallback((e: React.ChangeEvent<HTMLInputElement>) => {
+    const file = e.target.files?.[0]
+    if (file) processFile(file)
+  }, [processFile])
+
+  const handleCsvImport = useCallback(async () => {
+    setStep('importing')
+    setError(null)
+
+    try {
+      const mappedRows = csvRows.map(row => {
+        const obj: Record<string, string> = {}
+        for (const [fieldKey, csvCol] of Object.entries(mappings)) {
+          const colIdx = csvHeaders.indexOf(csvCol)
+          if (colIdx >= 0 && row[colIdx]) {
+            obj[fieldKey] = row[colIdx]
+          }
+        }
+        return obj
+      }).filter(row => Object.keys(row).length > 0)
+
+      const report = parseCsvRows(mappedRows)
+      await onImport(report, { source: 'csv', fileName, rowCount: mappedRows.length })
+      handleOpenChange(false)
+    } catch (e) {
+      setError(e instanceof Error ? e.message : 'Import misslyckades')
+      setStep('map-csv')
+    }
+  }, [csvRows, csvHeaders, mappings, parseCsvRows, onImport, fileName, handleOpenChange])
+
+  const handleJsonImport = useCallback(async () => {
+    if (!jsonReport) return
+    setStep('importing')
+    setError(null)
+
+    try {
+      await onImport(jsonReport, { source: 'json', fileName, rowCount: 0 })
+      handleOpenChange(false)
+    } catch (e) {
+      setError(e instanceof Error ? e.message : 'Import misslyckades')
+      setStep('preview-json')
+    }
+  }, [jsonReport, onImport, fileName, handleOpenChange])
+
+  const downloadTemplate = useCallback(() => {
+    const blob = new Blob([templateCsvContent], { type: 'text/csv;charset=utf-8;' })
+    const url = URL.createObjectURL(blob)
+    const a = document.createElement('a')
+    a.href = url
+    a.download = templateFileName
+    document.body.appendChild(a)
+    a.click()
+    document.body.removeChild(a)
+    URL.revokeObjectURL(url)
+  }, [templateCsvContent, templateFileName])
+
+  const requiredFieldsMapped = csvFields
+    .filter(f => f.required)
+    .every(f => mappings[f.key])
+
+  return (
+    <Dialog open={open} onOpenChange={handleOpenChange}>
+      <DialogContent className="max-w-2xl max-h-[85vh] overflow-y-auto">
+        <DialogHeader>
+          <DialogTitle>
+            {step === 'upload' && 'Importera testdata'}
+            {step === 'map-csv' && 'Kolumnmappning'}
+            {step === 'preview-json' && 'Förhandsgranska JSON'}
+            {step === 'importing' && 'Importerar...'}
+          </DialogTitle>
+        </DialogHeader>
+
+        {/* ── Error ─────────────────────────────────────── */}
+        {error && (
+          <div className="flex items-start gap-2 p-3 rounded-md bg-destructive/5 text-destructive text-sm">
+            <AlertCircle className="h-4 w-4 mt-0.5 shrink-0" />
+            <span>{error}</span>
+          </div>
+        )}
+
+        {/* ── Step: Upload ──────────────────────────────── */}
+        {step === 'upload' && (
+          <div className="space-y-4">
+            <div
+              className={cn(
+                'border-2 border-dashed rounded-lg p-10 text-center transition-colors',
+                isDragging
+                  ? 'border-primary bg-primary/5'
+                  : 'border-muted-foreground/25 hover:border-muted-foreground/50'
+              )}
+              onDragOver={(e) => { e.preventDefault(); setIsDragging(true) }}
+              onDragLeave={() => setIsDragging(false)}
+              onDrop={handleDrop}
+            >
+              <Upload className="h-8 w-8 mx-auto mb-3 text-muted-foreground" />
+              <p className="text-sm font-medium mb-1">
+                Dra och släpp en fil här
+              </p>
+              <p className="text-xs text-muted-foreground mb-4">
+                CSV (.csv) eller JSON (.json)
+              </p>
+              <Button
+                variant="outline"
+                size="sm"
+                onClick={() => fileInputRef.current?.click()}
+              >
+                Välj fil
+              </Button>
+              <input
+                ref={fileInputRef}
+                type="file"
+                accept=".csv,.json"
+                onChange={handleFileInput}
+                className="hidden"
+              />
+            </div>
+
+            <div className="flex items-center justify-center">
+              <Button
+                variant="ghost"
+                size="sm"
+                onClick={downloadTemplate}
+                className="text-xs text-muted-foreground"
+              >
+                <Download className="h-3.5 w-3.5 mr-1.5" />
+                Ladda ner CSV-mall
+              </Button>
+            </div>
+          </div>
+        )}
+
+        {/* ── Step: Map CSV ─────────────────────────────── */}
+        {step === 'map-csv' && (
+          <div className="space-y-4">
+            <div className="flex items-center gap-2 text-sm text-muted-foreground">
+              <FileSpreadsheet className="h-4 w-4" />
+              <span>{fileName} — {csvRows.length} rader</span>
+            </div>
+
+            <div className="space-y-3">
+              {csvFields.map(field => (
+                <div key={field.key} className="flex items-center gap-3">
+                  <Label className="w-40 text-sm shrink-0">
+                    {field.label}{field.required && ' *'}
+                  </Label>
+                  <Select
+                    value={mappings[field.key] ?? '___none___'}
+                    onValueChange={(val) => setMappings(prev => ({
+                      ...prev,
+                      [field.key]: val === '___none___' ? '' : val,
+                    }))}
+                  >
+                    <SelectTrigger className="w-full">
+                      <SelectValue placeholder="Välj kolumn..." />
+                    </SelectTrigger>
+                    <SelectContent>
+                      <SelectItem value="___none___">— Välj kolumn —</SelectItem>
+                      {csvHeaders.map(h => (
+                        <SelectItem key={h} value={h}>{h}</SelectItem>
+                      ))}
+                    </SelectContent>
+                  </Select>
+                </div>
+              ))}
+            </div>
+
+            {/* Preview first 5 rows */}
+            {csvRows.length > 0 && (
+              <div className="rounded-lg border overflow-auto max-h-48">
+                <Table>
+                  <TableHeader>
+                    <TableRow>
+                      {csvHeaders.map(h => (
+                        <TableHead key={h} className="text-xs whitespace-nowrap">{h}</TableHead>
+                      ))}
+                    </TableRow>
+                  </TableHeader>
+                  <TableBody>
+                    {csvRows.slice(0, 5).map((row, i) => (
+                      <TableRow key={i}>
+                        {row.map((cell, j) => (
+                          <TableCell key={j} className="text-xs whitespace-nowrap">{cell}</TableCell>
+                        ))}
+                      </TableRow>
+                    ))}
+                  </TableBody>
+                </Table>
+              </div>
+            )}
+
+            <DialogFooter>
+              <Button variant="outline" onClick={reset}>Tillbaka</Button>
+              <Button
+                onClick={handleCsvImport}
+                disabled={!requiredFieldsMapped}
+              >
+                Importera {csvRows.length} rader
+              </Button>
+            </DialogFooter>
+          </div>
+        )}
+
+        {/* ── Step: Preview JSON ────────────────────────── */}
+        {step === 'preview-json' && (
+          <div className="space-y-4">
+            <div className="flex items-center gap-2 text-sm text-muted-foreground">
+              <FileJson className="h-4 w-4" />
+              <span>{fileName}</span>
+            </div>
+
+            <div className="flex items-center gap-2 p-3 rounded-md bg-green-50 dark:bg-green-950/30 text-green-700 dark:text-green-400 text-sm">
+              <Check className="h-4 w-4 shrink-0" />
+              <span>Giltig JSON — {jsonSummary}</span>
+            </div>
+
+            <DialogFooter>
+              <Button variant="outline" onClick={reset}>Tillbaka</Button>
+              <Button onClick={handleJsonImport}>
+                Importera testdata
+              </Button>
+            </DialogFooter>
+          </div>
+        )}
+
+        {/* ── Step: Importing ───────────────────────────── */}
+        {step === 'importing' && (
+          <div className="py-8 text-center">
+            <div className="animate-spin h-8 w-8 border-2 border-primary border-t-transparent rounded-full mx-auto mb-3" />
+            <p className="text-sm text-muted-foreground">Importerar testdata...</p>
+          </div>
+        )}
+      </DialogContent>
+    </Dialog>
+  )
+}

extensions/export/currency-receivables/index.ts

@@ -0,0 +1,18 @@
+import type { Extension } from '@/lib/extensions/types'
+
+/**
+ * Multi-Currency Receivables Manager / Valutafordringar Extension
+ *
+ * Dashboard showing foreign currency exposure from open receivables.
+ * Calculates unrealized FX gains/losses using current Riksbanken rates
+ * compared to booking rates.
+ *
+ * Shows realized FX gains (account 3960) and losses (account 7960) per
+ * period, with monthly trend analysis. Provides period-end revaluation
+ * preview for informational purposes (does not create journal entries).
+ */
+export const currencyReceivablesExtension: Extension = {
+  id: 'currency-receivables',
+  name: 'Valutafordringar',
+  version: '1.0.0',
+}

extensions/export/currency-receivables/lib/__tests__/receivables-engine.test.ts

@@ -0,0 +1,465 @@
+import { describe, it, expect } from 'vitest'
+import {
+  generateReceivablesReport,
+  type ReceivableInvoice,
+  type ReceivableCustomer,
+  type GLLine,
+  type ExchangeRateInfo,
+  type ReceivablesOptions,
+} from '../receivables-engine'
+
+// ── Fixtures ────────────────────────────────────────────────
+
+function makeInvoice(overrides: Partial<ReceivableInvoice> = {}): ReceivableInvoice {
+  return {
+    id: 'inv-1',
+    invoice_number: 'F2026-001',
+    invoice_date: '2026-01-15',
+    due_date: '2026-02-15',
+    status: 'sent',
+    currency: 'EUR',
+    total: 10000,
+    total_sek: 114200,
+    exchange_rate: 11.42,
+    customer_id: 'cust-1',
+    ...overrides,
+  }
+}
+
+function makeCustomer(overrides: Partial<ReceivableCustomer> = {}): ReceivableCustomer {
+  return {
+    id: 'cust-1',
+    name: 'Müller GmbH',
+    country: 'DE',
+    ...overrides,
+  }
+}
+
+function makeRate(overrides: Partial<ExchangeRateInfo> = {}): ExchangeRateInfo {
+  return {
+    currency: 'EUR',
+    rate: 11.50,
+    date: '2026-03-15',
+    ...overrides,
+  }
+}
+
+function makeGLLine(overrides: Partial<GLLine> = {}): GLLine {
+  return {
+    account_number: '3960',
+    debit: 0,
+    credit: 0,
+    entry_date: '2026-01-31',
+    ...overrides,
+  }
+}
+
+const BASE_OPTIONS: ReceivablesOptions = {
+  invoices: [],
+  customers: [],
+  currentRates: [makeRate()],
+  realizedFXLines: [],
+  referenceDate: '2026-03-15',
+  year: 2026,
+}
+
+// ── Basic report tests ──────────────────────────────────────
+
+describe('generateReceivablesReport', () => {
+  it('generates empty report when no invoices', () => {
+    const report = generateReceivablesReport(BASE_OPTIONS)
+
+    expect(report.receivables).toHaveLength(0)
+    expect(report.exposureByCurrency).toHaveLength(0)
+    expect(report.totals.receivableCount).toBe(0)
+    expect(report.totals.currencyCount).toBe(0)
+    expect(report.totals.totalUnrealizedGainLoss).toBe(0)
+    expect(report.referenceDate).toBe('2026-03-15')
+  })
+
+  it('calculates unrealized gain when rate increases', () => {
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({
+        total: 10000,
+        total_sek: 114200, // Booked at 11.42
+        exchange_rate: 11.42,
+      })],
+      customers: [makeCustomer()],
+      currentRates: [makeRate({ rate: 11.50 })], // Current rate higher
+    })
+
+    expect(report.receivables).toHaveLength(1)
+    const r = report.receivables[0]
+    expect(r.bookedSekAmount).toBe(114200)
+    expect(r.currentSekAmount).toBe(115000) // 10000 × 11.50
+    expect(r.unrealizedGainLoss).toBe(800) // 115000 - 114200
+    expect(r.bookedRate).toBe(11.42)
+    expect(r.currentRate).toBe(11.50)
+  })
+
+  it('calculates unrealized loss when rate decreases', () => {
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({
+        total: 10000,
+        total_sek: 114200,
+        exchange_rate: 11.42,
+      })],
+      customers: [makeCustomer()],
+      currentRates: [makeRate({ rate: 11.00 })], // Current rate lower
+    })
+
+    const r = report.receivables[0]
+    expect(r.currentSekAmount).toBe(110000)
+    expect(r.unrealizedGainLoss).toBe(-4200) // 110000 - 114200
+  })
+
+  it('aggregates exposure by currency', () => {
+    const invoices = [
+      makeInvoice({ id: 'inv-1', total: 5000, total_sek: 57100, exchange_rate: 11.42 }),
+      makeInvoice({ id: 'inv-2', total: 3000, total_sek: 34260, exchange_rate: 11.42 }),
+    ]
+
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices,
+      customers: [makeCustomer()],
+      currentRates: [makeRate({ rate: 11.50 })],
+    })
+
+    expect(report.exposureByCurrency).toHaveLength(1)
+    const exp = report.exposureByCurrency[0]
+    expect(exp.currency).toBe('EUR')
+    expect(exp.totalForeignAmount).toBe(8000)
+    expect(exp.bookedSekValue).toBe(91360) // 57100 + 34260
+    expect(exp.currentSekValue).toBe(92000) // 8000 × 11.50
+    expect(exp.invoiceCount).toBe(2)
+    expect(exp.averageBookedRate).toBe(11.42) // 91360 / 8000
+    expect(exp.currentRate).toBe(11.50)
+  })
+
+  it('handles multiple currencies', () => {
+    const invoices = [
+      makeInvoice({ id: 'inv-1', currency: 'EUR', total: 5000, total_sek: 57100 }),
+      makeInvoice({ id: 'inv-2', currency: 'USD', total: 8000, total_sek: 84000, customer_id: 'cust-2' }),
+    ]
+    const customers = [
+      makeCustomer({ id: 'cust-1' }),
+      makeCustomer({ id: 'cust-2', name: 'Smith Inc', country: 'US' }),
+    ]
+    const rates = [
+      makeRate({ currency: 'EUR', rate: 11.50 }),
+      makeRate({ currency: 'USD', rate: 10.60 }),
+    ]
+
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices,
+      customers,
+      currentRates: rates,
+    })
+
+    expect(report.exposureByCurrency).toHaveLength(2)
+    expect(report.totals.currencyCount).toBe(2)
+    expect(report.totals.receivableCount).toBe(2)
+
+    const eurExp = report.exposureByCurrency.find(e => e.currency === 'EUR')!
+    const usdExp = report.exposureByCurrency.find(e => e.currency === 'USD')!
+    expect(eurExp.currentSekValue).toBe(57500) // 5000 × 11.50
+    expect(usdExp.currentSekValue).toBe(84800) // 8000 × 10.60
+  })
+
+  // ── Filtering ─────────────────────────────────────────────
+
+  it('excludes paid invoices', () => {
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ status: 'paid' })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.receivables).toHaveLength(0)
+  })
+
+  it('excludes SEK invoices', () => {
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ currency: 'SEK', total: 10000, total_sek: 10000 })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.receivables).toHaveLength(0)
+  })
+
+  it('excludes zero-amount invoices', () => {
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ total: 0 })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.receivables).toHaveLength(0)
+  })
+
+  it('includes overdue invoices', () => {
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ status: 'overdue' })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.receivables).toHaveLength(1)
+  })
+
+  // ── Booked value fallback ─────────────────────────────────
+
+  it('falls back to total × exchange_rate when total_sek is null', () => {
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ total: 5000, total_sek: null, exchange_rate: 11.42 })],
+      customers: [makeCustomer()],
+      currentRates: [makeRate({ rate: 11.50 })],
+    })
+
+    const r = report.receivables[0]
+    expect(r.bookedSekAmount).toBe(57100) // 5000 × 11.42
+    expect(r.currentSekAmount).toBe(57500) // 5000 × 11.50
+    expect(r.unrealizedGainLoss).toBe(400)
+  })
+
+  it('uses 0 booked value when no exchange rate info', () => {
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ total: 5000, total_sek: null, exchange_rate: null })],
+      customers: [makeCustomer()],
+      currentRates: [makeRate({ rate: 11.50 })],
+    })
+
+    const r = report.receivables[0]
+    expect(r.bookedSekAmount).toBe(0)
+    expect(r.currentSekAmount).toBe(57500)
+  })
+
+  // ── Days outstanding ──────────────────────────────────────
+
+  it('calculates days outstanding correctly', () => {
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ invoice_date: '2026-03-01' })],
+      customers: [makeCustomer()],
+      referenceDate: '2026-03-15',
+    })
+
+    expect(report.receivables[0].daysOutstanding).toBe(14)
+  })
+
+  // ── Realized FX from GL ───────────────────────────────────
+
+  it('calculates realized FX gains from account 3960 credits', () => {
+    const lines: GLLine[] = [
+      makeGLLine({ account_number: '3960', credit: 5000, debit: 0, entry_date: '2026-01-31' }),
+      makeGLLine({ account_number: '3960', credit: 3000, debit: 0, entry_date: '2026-02-28' }),
+    ]
+
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      realizedFXLines: lines,
+    })
+
+    expect(report.realizedGainLoss.gains).toBe(8000)
+    expect(report.realizedGainLoss.losses).toBe(0)
+    expect(report.realizedGainLoss.net).toBe(8000)
+  })
+
+  it('calculates realized FX losses from account 7960 debits', () => {
+    const lines: GLLine[] = [
+      makeGLLine({ account_number: '7960', debit: 3200, credit: 0, entry_date: '2026-01-31' }),
+      makeGLLine({ account_number: '7960', debit: 1800, credit: 0, entry_date: '2026-02-28' }),
+    ]
+
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      realizedFXLines: lines,
+    })
+
+    expect(report.realizedGainLoss.gains).toBe(0)
+    expect(report.realizedGainLoss.losses).toBe(5000)
+    expect(report.realizedGainLoss.net).toBe(-5000)
+  })
+
+  it('calculates net realized FX with both gains and losses', () => {
+    const lines: GLLine[] = [
+      makeGLLine({ account_number: '3960', credit: 8500, debit: 0, entry_date: '2026-01-31' }),
+      makeGLLine({ account_number: '7960', debit: 3200, credit: 0, entry_date: '2026-01-31' }),
+    ]
+
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      realizedFXLines: lines,
+    })
+
+    expect(report.realizedGainLoss.gains).toBe(8500)
+    expect(report.realizedGainLoss.losses).toBe(3200)
+    expect(report.realizedGainLoss.net).toBe(5300)
+  })
+
+  // ── Monthly trend ─────────────────────────────────────────
+
+  it('generates monthly trend with all 12 months', () => {
+    const report = generateReceivablesReport(BASE_OPTIONS)
+
+    expect(report.monthlyTrend).toHaveLength(12)
+    expect(report.monthlyTrend[0].month).toBe('2026-01')
+    expect(report.monthlyTrend[11].month).toBe('2026-12')
+  })
+
+  it('distributes realized FX to correct months', () => {
+    const lines: GLLine[] = [
+      makeGLLine({ account_number: '3960', credit: 5000, entry_date: '2026-01-15' }),
+      makeGLLine({ account_number: '7960', debit: 2000, entry_date: '2026-01-20' }),
+      makeGLLine({ account_number: '3960', credit: 8000, entry_date: '2026-03-10' }),
+    ]
+
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      realizedFXLines: lines,
+    })
+
+    const jan = report.monthlyTrend.find(t => t.month === '2026-01')!
+    expect(jan.realizedGains).toBe(5000)
+    expect(jan.realizedLosses).toBe(2000)
+    expect(jan.netRealized).toBe(3000)
+
+    const feb = report.monthlyTrend.find(t => t.month === '2026-02')!
+    expect(feb.realizedGains).toBe(0)
+    expect(feb.realizedLosses).toBe(0)
+    expect(feb.netRealized).toBe(0)
+
+    const mar = report.monthlyTrend.find(t => t.month === '2026-03')!
+    expect(mar.realizedGains).toBe(8000)
+    expect(mar.realizedLosses).toBe(0)
+    expect(mar.netRealized).toBe(8000)
+  })
+
+  // ── Revaluation preview ───────────────────────────────────
+
+  it('shows revaluation preview with net gain', () => {
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ total: 10000, total_sek: 114200 })],
+      customers: [makeCustomer()],
+      currentRates: [makeRate({ rate: 11.50 })],
+    })
+
+    expect(report.revalPreview.totalUnrealizedGainLoss).toBe(800)
+    expect(report.revalPreview.gains).toBe(800)
+    expect(report.revalPreview.losses).toBe(0)
+  })
+
+  it('shows revaluation preview with net loss', () => {
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ total: 10000, total_sek: 114200 })],
+      customers: [makeCustomer()],
+      currentRates: [makeRate({ rate: 11.00 })],
+    })
+
+    expect(report.revalPreview.totalUnrealizedGainLoss).toBe(-4200)
+    expect(report.revalPreview.gains).toBe(0)
+    expect(report.revalPreview.losses).toBe(4200)
+  })
+
+  // ── Customer data ─────────────────────────────────────────
+
+  it('uses customer name and country from customer lookup', () => {
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      customers: [makeCustomer({ name: 'Acme Corp', country: 'FI' })],
+    })
+
+    expect(report.receivables[0].customerName).toBe('Acme Corp')
+    expect(report.receivables[0].customerCountry).toBe('FI')
+  })
+
+  it('falls back to unknown customer when not found', () => {
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ customer_id: 'unknown' })],
+      customers: [makeCustomer()], // cust-1, not 'unknown'
+    })
+
+    expect(report.receivables[0].customerName).toBe('Okänd kund')
+  })
+
+  // ── Totals ────────────────────────────────────────────────
+
+  it('calculates correct totals across all receivables', () => {
+    const invoices = [
+      makeInvoice({ id: 'inv-1', currency: 'EUR', total: 5000, total_sek: 57100 }),
+      makeInvoice({ id: 'inv-2', currency: 'USD', total: 3000, total_sek: 31500, customer_id: 'cust-2' }),
+    ]
+    const customers = [
+      makeCustomer({ id: 'cust-1' }),
+      makeCustomer({ id: 'cust-2', name: 'Smith Inc', country: 'US' }),
+    ]
+    const rates = [
+      makeRate({ currency: 'EUR', rate: 11.50 }),
+      makeRate({ currency: 'USD', rate: 10.60 }),
+    ]
+
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices,
+      customers,
+      currentRates: rates,
+    })
+
+    // EUR: 5000 × 11.50 = 57500, USD: 3000 × 10.60 = 31800
+    expect(report.totals.bookedSekValue).toBe(88600) // 57100 + 31500
+    expect(report.totals.currentSekValue).toBe(89300) // 57500 + 31800
+    expect(report.totals.totalUnrealizedGainLoss).toBe(700) // 89300 - 88600
+    expect(report.totals.receivableCount).toBe(2)
+    expect(report.totals.currencyCount).toBe(2)
+  })
+
+  // ── Period info ───────────────────────────────────────────
+
+  it('includes year and exchange rate info', () => {
+    const rates = [
+      makeRate({ currency: 'EUR', rate: 11.50 }),
+      makeRate({ currency: 'USD', rate: 10.60 }),
+    ]
+
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      currentRates: rates,
+    })
+
+    expect(report.realizedGainLoss.year).toBe(2026)
+    expect(report.exchangeRates).toHaveLength(2)
+    expect(report.exchangeRates.find(r => r.currency === 'EUR')?.rate).toBe(11.50)
+  })
+
+  // ── Sorting ───────────────────────────────────────────────
+
+  it('sorts receivables by absolute unrealized gain/loss descending', () => {
+    const invoices = [
+      makeInvoice({ id: 'inv-1', total: 1000, total_sek: 11420 }), // gain: 80
+      makeInvoice({ id: 'inv-2', total: 5000, total_sek: 57100, customer_id: 'cust-1' }), // gain: 400
+      makeInvoice({ id: 'inv-3', total: 2000, total_sek: 22840, customer_id: 'cust-1' }), // gain: 160
+    ]
+
+    const report = generateReceivablesReport({
+      ...BASE_OPTIONS,
+      invoices,
+      customers: [makeCustomer()],
+      currentRates: [makeRate({ rate: 11.50 })],
+    })
+
+    expect(report.receivables[0].foreignAmount).toBe(5000) // largest gain
+    expect(report.receivables[1].foreignAmount).toBe(2000)
+    expect(report.receivables[2].foreignAmount).toBe(1000) // smallest gain
+  })
+})

extensions/export/currency-receivables/lib/receivables-engine.ts

@@ -0,0 +1,359 @@
+/**
+ * Multi-Currency Receivables Engine
+ *
+ * Pure-function engine that calculates foreign currency exposure from
+ * open receivables, unrealized FX gains/losses vs. current Riksbanken
+ * rates, and realized FX gains/losses from GL accounts 3960/7960.
+ *
+ * This extension is READ-ONLY — it does not create journal entries.
+ * The revaluation preview is informational only.
+ */
+
+// ── Types ──────────────────────────────────────────────────────
+
+/** Minimal invoice data needed by the engine */
+export interface ReceivableInvoice {
+  id: string
+  invoice_number: string
+  invoice_date: string
+  due_date: string
+  status: string
+  currency: string
+  total: number
+  total_sek: number | null
+  exchange_rate: number | null
+  customer_id: string
+}
+
+/** Minimal customer data */
+export interface ReceivableCustomer {
+  id: string
+  name: string
+  country: string
+}
+
+/** GL line for realized FX */
+export interface GLLine {
+  account_number: string
+  debit: number
+  credit: number
+  entry_date: string
+}
+
+/** Current exchange rate */
+export interface ExchangeRateInfo {
+  currency: string
+  rate: number
+  date: string
+}
+
+/** Engine options */
+export interface ReceivablesOptions {
+  /** Open (unpaid) foreign-currency invoices */
+  invoices: ReceivableInvoice[]
+  /** Customers for those invoices */
+  customers: ReceivableCustomer[]
+  /** Current exchange rates from Riksbanken */
+  currentRates: ExchangeRateInfo[]
+  /** GL lines on accounts 3960 and 7960 for the selected year */
+  realizedFXLines: GLLine[]
+  /** Reference date (for days outstanding calculation) */
+  referenceDate: string
+  /** Selected year for realized FX */
+  year: number
+}
+
+// ── Output types ───────────────────────────────────────────────
+
+export interface CurrencyExposure {
+  currency: string
+  totalForeignAmount: number
+  bookedSekValue: number
+  currentSekValue: number
+  unrealizedGainLoss: number
+  invoiceCount: number
+  averageBookedRate: number
+  currentRate: number
+}
+
+export interface ForeignReceivable {
+  invoiceId: string
+  invoiceNumber: string
+  customerName: string
+  customerCountry: string
+  currency: string
+  foreignAmount: number
+  bookedSekAmount: number
+  bookedRate: number
+  currentSekAmount: number
+  currentRate: number
+  unrealizedGainLoss: number
+  invoiceDate: string
+  dueDate: string
+  daysOutstanding: number
+}
+
+export interface MonthlyFXTrend {
+  month: string // 'YYYY-MM'
+  realizedGains: number
+  realizedLosses: number
+  netRealized: number
+}
+
+export interface RevalPreview {
+  totalUnrealizedGainLoss: number
+  gains: number   // Positive: amount for account 3969
+  losses: number  // Positive: amount for account 7969
+}
+
+export interface ReceivablesReport {
+  referenceDate: string
+  exchangeRates: ExchangeRateInfo[]
+
+  exposureByCurrency: CurrencyExposure[]
+  receivables: ForeignReceivable[]
+
+  realizedGainLoss: {
+    year: number
+    gains: number
+    losses: number
+    net: number
+  }
+
+  monthlyTrend: MonthlyFXTrend[]
+  revalPreview: RevalPreview
+
+  totals: {
+    bookedSekValue: number
+    currentSekValue: number
+    totalUnrealizedGainLoss: number
+    receivableCount: number
+    currencyCount: number
+  }
+}
+
+// ── Constants ──────────────────────────────────────────────────
+
+const ACCOUNT_FX_GAINS = '3960'
+const ACCOUNT_FX_LOSSES = '7960'
+
+const OPEN_STATUSES = ['sent', 'overdue']
+
+// ── Engine ─────────────────────────────────────────────────────
+
+export function generateReceivablesReport(options: ReceivablesOptions): ReceivablesReport {
+  const { invoices, customers, currentRates, realizedFXLines, referenceDate, year } = options
+
+  const rateMap = new Map<string, ExchangeRateInfo>()
+  for (const r of currentRates) {
+    rateMap.set(r.currency.toUpperCase(), r)
+  }
+
+  const customerMap = new Map<string, ReceivableCustomer>()
+  for (const c of customers) {
+    customerMap.set(c.id, c)
+  }
+
+  // Filter to open foreign-currency invoices
+  const foreignInvoices = invoices.filter(inv =>
+    OPEN_STATUSES.includes(inv.status) &&
+    inv.currency !== 'SEK' &&
+    inv.total > 0
+  )
+
+  // Build receivable details
+  const receivables: ForeignReceivable[] = []
+  for (const inv of foreignInvoices) {
+    const customer = customerMap.get(inv.customer_id)
+    const rateInfo = rateMap.get(inv.currency.toUpperCase())
+    const currentRate = rateInfo?.rate ?? 0
+
+    const bookedSekAmount = getBookedSekAmount(inv)
+    const bookedRate = inv.total > 0 ? bookedSekAmount / inv.total : 0
+    const currentSekAmount = round2(inv.total * currentRate)
+    const unrealizedGainLoss = round2(currentSekAmount - bookedSekAmount)
+    const daysOutstanding = daysBetween(inv.invoice_date, referenceDate)
+
+    receivables.push({
+      invoiceId: inv.id,
+      invoiceNumber: inv.invoice_number,
+      customerName: customer?.name ?? 'Okänd kund',
+      customerCountry: customer?.country ?? '',
+      currency: inv.currency,
+      foreignAmount: inv.total,
+      bookedSekAmount,
+      bookedRate: round4(bookedRate),
+      currentSekAmount,
+      currentRate: round4(currentRate),
+      unrealizedGainLoss,
+      invoiceDate: inv.invoice_date,
+      dueDate: inv.due_date,
+      daysOutstanding,
+    })
+  }
+
+  // Sort by unrealized gain/loss (largest absolute first)
+  receivables.sort((a, b) => Math.abs(b.unrealizedGainLoss) - Math.abs(a.unrealizedGainLoss))
+
+  // Aggregate by currency
+  const exposureMap = new Map<string, {
+    totalForeign: number
+    bookedSek: number
+    currentSek: number
+    count: number
+  }>()
+
+  for (const r of receivables) {
+    const existing = exposureMap.get(r.currency) || { totalForeign: 0, bookedSek: 0, currentSek: 0, count: 0 }
+    existing.totalForeign += r.foreignAmount
+    existing.bookedSek += r.bookedSekAmount
+    existing.currentSek += r.currentSekAmount
+    existing.count += 1
+    exposureMap.set(r.currency, existing)
+  }
+
+  const exposureByCurrency: CurrencyExposure[] = []
+  for (const [currency, agg] of exposureMap.entries()) {
+    const rateInfo = rateMap.get(currency.toUpperCase())
+    exposureByCurrency.push({
+      currency,
+      totalForeignAmount: round2(agg.totalForeign),
+      bookedSekValue: round2(agg.bookedSek),
+      currentSekValue: round2(agg.currentSek),
+      unrealizedGainLoss: round2(agg.currentSek - agg.bookedSek),
+      invoiceCount: agg.count,
+      averageBookedRate: agg.totalForeign > 0 ? round4(agg.bookedSek / agg.totalForeign) : 0,
+      currentRate: rateInfo?.rate ?? 0,
+    })
+  }
+
+  // Sort exposures by absolute unrealized gain/loss descending
+  exposureByCurrency.sort((a, b) => Math.abs(b.unrealizedGainLoss) - Math.abs(a.unrealizedGainLoss))
+
+  // Calculate realized FX from GL
+  const { gains, losses } = calculateRealizedFX(realizedFXLines)
+
+  // Monthly trend
+  const monthlyTrend = calculateMonthlyTrend(realizedFXLines, year)
+
+  // Revaluation preview
+  const totalBooked = receivables.reduce((sum, r) => sum + r.bookedSekAmount, 0)
+  const totalCurrent = receivables.reduce((sum, r) => sum + r.currentSekAmount, 0)
+  const totalUnrealized = round2(totalCurrent - totalBooked)
+
+  const revalPreview: RevalPreview = {
+    totalUnrealizedGainLoss: totalUnrealized,
+    gains: round2(Math.max(0, totalUnrealized)),
+    losses: round2(Math.abs(Math.min(0, totalUnrealized))),
+  }
+
+  const currencies = new Set(receivables.map(r => r.currency))
+
+  return {
+    referenceDate,
+    exchangeRates: currentRates,
+    exposureByCurrency,
+    receivables,
+    realizedGainLoss: {
+      year,
+      gains: round2(gains),
+      losses: round2(losses),
+      net: round2(gains - losses),
+    },
+    monthlyTrend,
+    revalPreview,
+    totals: {
+      bookedSekValue: round2(totalBooked),
+      currentSekValue: round2(totalCurrent),
+      totalUnrealizedGainLoss: totalUnrealized,
+      receivableCount: receivables.length,
+      currencyCount: currencies.size,
+    },
+  }
+}
+
+// ── Helpers ────────────────────────────────────────────────────
+
+function getBookedSekAmount(inv: ReceivableInvoice): number {
+  // Prefer the explicitly stored SEK amount
+  if (inv.total_sek !== null && inv.total_sek !== undefined) {
+    return round2(inv.total_sek)
+  }
+  // Fallback: total × exchange_rate at invoice date
+  if (inv.exchange_rate !== null && inv.exchange_rate !== undefined) {
+    return round2(inv.total * inv.exchange_rate)
+  }
+  // No rate info — return 0 (will show as warning in UI)
+  return 0
+}
+
+function calculateRealizedFX(lines: GLLine[]): { gains: number; losses: number } {
+  let gains = 0
+  let losses = 0
+
+  for (const line of lines) {
+    if (line.account_number === ACCOUNT_FX_GAINS) {
+      // FX gains are booked as credits on 3960
+      gains += line.credit - line.debit
+    } else if (line.account_number === ACCOUNT_FX_LOSSES) {
+      // FX losses are booked as debits on 7960
+      losses += line.debit - line.credit
+    }
+  }
+
+  return { gains: Math.max(0, gains), losses: Math.max(0, losses) }
+}
+
+function calculateMonthlyTrend(lines: GLLine[], year: number): MonthlyFXTrend[] {
+  const monthData = new Map<string, { gains: number; losses: number }>()
+
+  // Initialize all 12 months
+  for (let m = 1; m <= 12; m++) {
+    const key = `${year}-${String(m).padStart(2, '0')}`
+    monthData.set(key, { gains: 0, losses: 0 })
+  }
+
+  for (const line of lines) {
+    const monthKey = line.entry_date.substring(0, 7) // 'YYYY-MM'
+    const data = monthData.get(monthKey)
+    if (!data) continue
+
+    if (line.account_number === ACCOUNT_FX_GAINS) {
+      data.gains += line.credit - line.debit
+    } else if (line.account_number === ACCOUNT_FX_LOSSES) {
+      data.losses += line.debit - line.credit
+    }
+  }
+
+  const trend: MonthlyFXTrend[] = []
+  for (const [month, data] of monthData.entries()) {
+    const gains = Math.max(0, round2(data.gains))
+    const losses = Math.max(0, round2(data.losses))
+    trend.push({
+      month,
+      realizedGains: gains,
+      realizedLosses: losses,
+      netRealized: round2(gains - losses),
+    })
+  }
+
+  // Sort chronologically
+  trend.sort((a, b) => a.month.localeCompare(b.month))
+
+  return trend
+}
+
+function daysBetween(dateStr: string, refDateStr: string): number {
+  const d1 = new Date(dateStr)
+  const d2 = new Date(refDateStr)
+  const diffMs = d2.getTime() - d1.getTime()
+  return Math.max(0, Math.floor(diffMs / (1000 * 60 * 60 * 24)))
+}
+
+function round2(n: number): number {
+  return Math.round(n * 100) / 100
+}
+
+function round4(n: number): number {
+  return Math.round(n * 10000) / 10000
+}

extensions/export/eu-sales-list/index.ts

@@ -0,0 +1,18 @@
+import type { Extension } from '@/lib/extensions/types'
+
+/**
+ * EU Sales List / Periodisk Sammanställning Extension
+ *
+ * Generates the mandatory EC Sales List (periodisk sammanställning) report
+ * for Skatteverket. Aggregates intra-community B2B sales by customer VAT
+ * number, separating goods (box 35) from services (box 39).
+ *
+ * Outputs downloadable CSV/XML files for upload to Skatteverket's e-service.
+ * Validates customer VAT numbers via VIES and cross-checks against
+ * momsdeklaration box totals.
+ */
+export const euSalesListExtension: Extension = {
+  id: 'eu-sales-list',
+  name: 'Periodisk sammanställning',
+  version: '1.0.0',
+}

extensions/export/eu-sales-list/lib/__tests__/csv-generator.test.ts

@@ -0,0 +1,140 @@
+import { describe, it, expect } from 'vitest'
+import { generateCSV, generateCSVFilename } from '../csv-generator'
+import type { ECSalesListReport } from '../eu-sales-list-engine'
+
+function makeReport(overrides: Partial<ECSalesListReport> = {}): ECSalesListReport {
+  return {
+    period: { year: 2026, quarter: 1 },
+    filingType: 'quarterly',
+    reporterVatNumber: 'SE556677889901',
+    reporterName: 'Test AB',
+    lines: [
+      {
+        customerVatNumber: 'DE123456789',
+        customerName: 'Acme GmbH',
+        customerCountry: 'DE',
+        customerId: 'cust-1',
+        goodsAmount: 50000,
+        servicesAmount: 30000,
+        triangulationAmount: 0,
+        invoiceCount: 3,
+      },
+    ],
+    totals: { goods: 50000, services: 30000, triangulation: 0, total: 80000 },
+    warnings: [],
+    crossCheck: null,
+    invoiceCount: 3,
+    customerCount: 1,
+    ...overrides,
+  }
+}
+
+describe('generateCSV', () => {
+  it('starts with UTF-8 BOM', () => {
+    const csv = generateCSV(makeReport())
+    expect(csv.charCodeAt(0)).toBe(0xFEFF)
+  })
+
+  it('uses semicolons as delimiter', () => {
+    const csv = generateCSV(makeReport())
+    const headerLine = csv.split('\r\n')[0].replace('\uFEFF', '')
+    expect(headerLine).toContain(';')
+    expect(headerLine).not.toContain(',')
+  })
+
+  it('has correct header columns', () => {
+    const csv = generateCSV(makeReport())
+    const header = csv.split('\r\n')[0].replace('\uFEFF', '')
+    expect(header).toBe('Land;VAT-nummer;Varuförsäljning (SEK);Tjänsteförsäljning (SEK);Trepartshandel (SEK)')
+  })
+
+  it('includes customer data rows', () => {
+    const csv = generateCSV(makeReport())
+    const lines = csv.split('\r\n')
+    expect(lines[1]).toBe('DE;DE123456789;50000;30000;0')
+  })
+
+  it('rounds amounts to whole SEK', () => {
+    const report = makeReport({
+      lines: [{
+        customerVatNumber: 'DE123',
+        customerName: 'Test',
+        customerCountry: 'DE',
+        customerId: 'c-1',
+        goodsAmount: 12345.67,
+        servicesAmount: 89012.34,
+        triangulationAmount: 0,
+        invoiceCount: 1,
+      }],
+      totals: { goods: 12345.67, services: 89012.34, triangulation: 0, total: 101358.01 },
+    })
+
+    const csv = generateCSV(report)
+    const dataLine = csv.split('\r\n')[1]
+    expect(dataLine).toBe('DE;DE123;12346;89012;0')
+  })
+
+  it('includes summary row', () => {
+    const csv = generateCSV(makeReport())
+    const lines = csv.split('\r\n')
+    const summaryIndex = lines.findIndex(l => l.startsWith('Summa'))
+    expect(summaryIndex).toBeGreaterThan(0)
+    expect(lines[summaryIndex]).toBe('Summa;;50000;30000;0')
+  })
+
+  it('uses CRLF line endings', () => {
+    const csv = generateCSV(makeReport())
+    expect(csv).toContain('\r\n')
+  })
+
+  it('handles multiple customers', () => {
+    const report = makeReport({
+      lines: [
+        {
+          customerVatNumber: 'DE111',
+          customerName: 'A',
+          customerCountry: 'DE',
+          customerId: 'c-1',
+          goodsAmount: 10000,
+          servicesAmount: 0,
+          triangulationAmount: 0,
+          invoiceCount: 1,
+        },
+        {
+          customerVatNumber: 'FR222',
+          customerName: 'B',
+          customerCountry: 'FR',
+          customerId: 'c-2',
+          goodsAmount: 0,
+          servicesAmount: 20000,
+          triangulationAmount: 0,
+          invoiceCount: 2,
+        },
+      ],
+    })
+
+    const csv = generateCSV(report)
+    const lines = csv.split('\r\n')
+    expect(lines[1]).toBe('DE;DE111;10000;0;0')
+    expect(lines[2]).toBe('FR;FR222;0;20000;0')
+  })
+})
+
+describe('generateCSVFilename', () => {
+  it('generates quarterly filename', () => {
+    const filename = generateCSVFilename(makeReport())
+    expect(filename).toBe('PS_SE556677889901_2026-Q1.csv')
+  })
+
+  it('generates monthly filename', () => {
+    const report = makeReport({ period: { year: 2026, month: 3 }, filingType: 'monthly' })
+    const filename = generateCSVFilename(report)
+    expect(filename).toBe('PS_SE556677889901_2026-03.csv')
+  })
+
+  it('strips spaces from VAT number', () => {
+    const report = makeReport({ reporterVatNumber: 'SE 5566 7788 9901' })
+    const filename = generateCSVFilename(report)
+    expect(filename).toBe('PS_SE556677889901_2026-Q1.csv')
+  })
+})

extensions/export/eu-sales-list/lib/__tests__/eu-sales-list-engine.test.ts

@@ -0,0 +1,559 @@
+import { describe, it, expect } from 'vitest'
+import {
+  generateECSalesListReport,
+  getMonthPeriod,
+  getQuarterPeriod,
+  getFilingDeadline,
+  daysUntilDeadline,
+  type ECSalesListInvoice,
+  type ECSalesListCustomer,
+  type GLAccountTotal,
+} from '../eu-sales-list-engine'
+
+// ── Test fixtures ─────────────────────────────────────────────
+
+function makeInvoice(overrides: Partial<ECSalesListInvoice> = {}): ECSalesListInvoice {
+  return {
+    id: 'inv-1',
+    invoice_number: 'F2026-001',
+    invoice_date: '2026-01-15',
+    status: 'sent',
+    currency: 'EUR',
+    total: 10000,
+    total_sek: 112000,
+    subtotal: 10000,
+    subtotal_sek: 112000,
+    vat_treatment: 'reverse_charge',
+    moms_ruta: '35',
+    document_type: 'invoice',
+    credited_invoice_id: null,
+    customer_id: 'cust-1',
+    ...overrides,
+  }
+}
+
+function makeCustomer(overrides: Partial<ECSalesListCustomer> = {}): ECSalesListCustomer {
+  return {
+    id: 'cust-1',
+    name: 'Acme GmbH',
+    country: 'DE',
+    customer_type: 'eu_business',
+    vat_number: 'DE123456789',
+    vat_number_validated: true,
+    ...overrides,
+  }
+}
+
+const BASE_OPTIONS = {
+  reporterVatNumber: 'SE556677889901',
+  reporterName: 'Test AB',
+  year: 2026,
+  month: 1 as number | undefined,
+  quarter: undefined as number | undefined,
+}
+
+// ── Report generation tests ───────────────────────────────────
+
+describe('generateECSalesListReport', () => {
+  it('generates empty report when no invoices', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [],
+      customers: [],
+    })
+
+    expect(report.lines).toHaveLength(0)
+    expect(report.totals.goods).toBe(0)
+    expect(report.totals.services).toBe(0)
+    expect(report.totals.total).toBe(0)
+    expect(report.invoiceCount).toBe(0)
+    expect(report.customerCount).toBe(0)
+    expect(report.warnings).toHaveLength(0)
+  })
+
+  it('aggregates goods invoice correctly (moms_ruta 35)', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ moms_ruta: '35', subtotal_sek: 50000 })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.lines).toHaveLength(1)
+    expect(report.lines[0].goodsAmount).toBe(50000)
+    expect(report.lines[0].servicesAmount).toBe(0)
+    expect(report.totals.goods).toBe(50000)
+    expect(report.invoiceCount).toBe(1)
+  })
+
+  it('aggregates service invoice correctly (moms_ruta 39)', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ moms_ruta: '39', subtotal_sek: 30000 })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.lines[0].servicesAmount).toBe(30000)
+    expect(report.lines[0].goodsAmount).toBe(0)
+    expect(report.totals.services).toBe(30000)
+  })
+
+  it('aggregates triangulation invoice correctly (moms_ruta 38)', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ moms_ruta: '38', subtotal_sek: 20000 })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.lines[0].triangulationAmount).toBe(20000)
+    expect(report.totals.triangulation).toBe(20000)
+  })
+
+  it('defaults to services when moms_ruta is null', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ moms_ruta: null, subtotal_sek: 15000 })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.lines[0].servicesAmount).toBe(15000)
+    expect(report.lines[0].goodsAmount).toBe(0)
+  })
+
+  it('groups multiple invoices by customer VAT number', () => {
+    const invoices = [
+      makeInvoice({ id: 'inv-1', subtotal_sek: 10000, moms_ruta: '35' }),
+      makeInvoice({ id: 'inv-2', subtotal_sek: 20000, moms_ruta: '35' }),
+      makeInvoice({ id: 'inv-3', subtotal_sek: 5000, moms_ruta: '39' }),
+    ]
+
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices,
+      customers: [makeCustomer()],
+    })
+
+    expect(report.lines).toHaveLength(1)
+    expect(report.lines[0].goodsAmount).toBe(30000)
+    expect(report.lines[0].servicesAmount).toBe(5000)
+    expect(report.lines[0].invoiceCount).toBe(3)
+  })
+
+  it('separates different customers into different lines', () => {
+    const invoices = [
+      makeInvoice({ id: 'inv-1', customer_id: 'cust-1', subtotal_sek: 10000 }),
+      makeInvoice({ id: 'inv-2', customer_id: 'cust-2', subtotal_sek: 20000 }),
+    ]
+    const customers = [
+      makeCustomer({ id: 'cust-1', vat_number: 'DE111111111', country: 'DE' }),
+      makeCustomer({ id: 'cust-2', vat_number: 'FR222222222', country: 'FR', name: 'Fromage SARL' }),
+    ]
+
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices,
+      customers,
+    })
+
+    expect(report.lines).toHaveLength(2)
+    expect(report.customerCount).toBe(2)
+    // Sorted by country, so DE comes before FR
+    expect(report.lines[0].customerCountry).toBe('DE')
+    expect(report.lines[1].customerCountry).toBe('FR')
+  })
+
+  it('handles credit notes (subtracts from customer total)', () => {
+    const invoices = [
+      makeInvoice({ id: 'inv-1', subtotal_sek: 50000, moms_ruta: '35' }),
+      makeInvoice({
+        id: 'inv-2',
+        subtotal_sek: 10000,
+        moms_ruta: '35',
+        credited_invoice_id: 'inv-1',
+      }),
+    ]
+
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices,
+      customers: [makeCustomer()],
+    })
+
+    expect(report.lines[0].goodsAmount).toBe(40000) // 50000 - 10000
+    expect(report.invoiceCount).toBe(2)
+  })
+
+  it('uses subtotal (not total) for amounts', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ subtotal_sek: 80000, total_sek: 100000, moms_ruta: '35' })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.lines[0].goodsAmount).toBe(80000)
+  })
+
+  it('falls back to subtotal when subtotal_sek is null (SEK invoices)', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ subtotal_sek: null, subtotal: 45000, moms_ruta: '35' })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.lines[0].goodsAmount).toBe(45000)
+  })
+
+  // ── Filtering tests ──────────────────────────────────────
+
+  it('excludes draft invoices', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ status: 'draft' })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.lines).toHaveLength(0)
+    expect(report.invoiceCount).toBe(0)
+  })
+
+  it('excludes non-reverse-charge invoices', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ vat_treatment: 'standard_25' })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.lines).toHaveLength(0)
+  })
+
+  it('includes paid and overdue invoices', () => {
+    const invoices = [
+      makeInvoice({ id: 'inv-1', status: 'paid', subtotal_sek: 10000 }),
+      makeInvoice({ id: 'inv-2', status: 'overdue', subtotal_sek: 20000 }),
+    ]
+
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices,
+      customers: [makeCustomer()],
+    })
+
+    expect(report.invoiceCount).toBe(2)
+  })
+
+  it('excludes proforma documents without credit note link', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ document_type: 'proforma', credited_invoice_id: null })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.lines).toHaveLength(0)
+  })
+
+  it('includes credit notes even with non-invoice document type', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({
+        document_type: 'credit_note',
+        credited_invoice_id: 'inv-original',
+        subtotal_sek: 5000,
+        moms_ruta: '35',
+      })],
+      customers: [makeCustomer()],
+    })
+
+    // Credit note creates a line with negative amount
+    expect(report.lines).toHaveLength(1)
+    expect(report.lines[0].goodsAmount).toBe(-5000)
+  })
+
+  // ── Warning tests ────────────────────────────────────────
+
+  it('warns on missing VAT number (error severity)', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      customers: [makeCustomer({ vat_number: null })],
+    })
+
+    expect(report.warnings).toHaveLength(1)
+    expect(report.warnings[0].type).toBe('missing_vat_number')
+    expect(report.warnings[0].severity).toBe('error')
+    // Invoice is excluded from lines when VAT number missing
+    expect(report.lines).toHaveLength(0)
+  })
+
+  it('warns on unvalidated VAT number (warning severity)', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      customers: [makeCustomer({ vat_number_validated: false })],
+    })
+
+    const unvalidatedWarnings = report.warnings.filter(w => w.type === 'unvalidated_vat_number')
+    expect(unvalidatedWarnings).toHaveLength(1)
+    expect(unvalidatedWarnings[0].severity).toBe('warning')
+    // Invoice is still included in report
+    expect(report.lines).toHaveLength(1)
+  })
+
+  it('warns on non-EU country', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      customers: [makeCustomer({ country: 'US' })],
+    })
+
+    expect(report.warnings).toHaveLength(1)
+    expect(report.warnings[0].type).toBe('non_eu_country')
+    expect(report.lines).toHaveLength(0)
+  })
+
+  it('excludes Sweden (SE) as non-intra-community', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      customers: [makeCustomer({ country: 'SE' })],
+    })
+
+    expect(report.warnings).toHaveLength(1)
+    expect(report.warnings[0].type).toBe('non_eu_country')
+    expect(report.lines).toHaveLength(0)
+  })
+
+  // ── Cross-check tests ────────────────────────────────────
+
+  it('cross-check passes when GL matches report totals', () => {
+    const glTotals: GLAccountTotal[] = [
+      { account_number: '3108', credit: 50000 },
+      { account_number: '3308', credit: 30000 },
+    ]
+
+    const invoices = [
+      makeInvoice({ id: 'inv-1', subtotal_sek: 50000, moms_ruta: '35' }),
+      makeInvoice({ id: 'inv-2', subtotal_sek: 30000, moms_ruta: '39' }),
+    ]
+
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices,
+      customers: [makeCustomer()],
+      glTotals,
+    })
+
+    expect(report.crossCheck).not.toBeNull()
+    expect(report.crossCheck!.box35Match).toBe(true)
+    expect(report.crossCheck!.box39Match).toBe(true)
+  })
+
+  it('cross-check fails when GL does not match', () => {
+    const glTotals: GLAccountTotal[] = [
+      { account_number: '3108', credit: 99999 },
+      { account_number: '3308', credit: 30000 },
+    ]
+
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ subtotal_sek: 50000, moms_ruta: '35' })],
+      customers: [makeCustomer()],
+      glTotals,
+    })
+
+    expect(report.crossCheck!.box35Match).toBe(false)
+    const mismatchWarnings = report.warnings.filter(w => w.type === 'cross_check_mismatch')
+    expect(mismatchWarnings.length).toBeGreaterThan(0)
+  })
+
+  it('cross-check allows 1 SEK rounding tolerance', () => {
+    const glTotals: GLAccountTotal[] = [
+      { account_number: '3108', credit: 50000.50 },
+    ]
+
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ subtotal_sek: 50000, moms_ruta: '35' })],
+      customers: [makeCustomer()],
+      glTotals,
+    })
+
+    expect(report.crossCheck!.box35Match).toBe(true)
+  })
+
+  it('cross-check sums multiple accounts for box 35 (3108 + 3521)', () => {
+    const glTotals: GLAccountTotal[] = [
+      { account_number: '3108', credit: 40000 },
+      { account_number: '3521', credit: 10000 },
+    ]
+
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ subtotal_sek: 50000, moms_ruta: '35' })],
+      customers: [makeCustomer()],
+      glTotals,
+    })
+
+    expect(report.crossCheck!.box35Match).toBe(true)
+    expect(report.crossCheck!.box35GLTotal).toBe(50000)
+  })
+
+  it('skips cross-check when no GL data provided', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.crossCheck).toBeNull()
+  })
+
+  // ── Period and metadata tests ────────────────────────────
+
+  it('sets filingType to monthly when month is provided', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [],
+      customers: [],
+      month: 3,
+      quarter: undefined,
+    })
+
+    expect(report.filingType).toBe('monthly')
+    expect(report.period.month).toBe(3)
+  })
+
+  it('sets filingType to quarterly when quarter is provided', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [],
+      customers: [],
+      month: undefined,
+      quarter: 2,
+    })
+
+    expect(report.filingType).toBe('quarterly')
+    expect(report.period.quarter).toBe(2)
+  })
+
+  it('includes reporter info in report', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [],
+      customers: [],
+    })
+
+    expect(report.reporterVatNumber).toBe('SE556677889901')
+    expect(report.reporterName).toBe('Test AB')
+  })
+
+  // ── Monetary precision tests ─────────────────────────────
+
+  it('rounds amounts to 2 decimal places', () => {
+    const report = generateECSalesListReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ subtotal_sek: 33333.335, moms_ruta: '35' })],
+      customers: [makeCustomer()],
+    })
+
+    expect(report.lines[0].goodsAmount).toBe(33333.34)
+  })
+})
+
+// ── Period helper tests ───────────────────────────────────────
+
+describe('getMonthPeriod', () => {
+  it('returns correct start and end for January', () => {
+    const { start, end } = getMonthPeriod(2026, 1)
+    expect(start).toBe('2026-01-01')
+    expect(end).toBe('2026-01-31')
+  })
+
+  it('handles February in a non-leap year', () => {
+    const { start, end } = getMonthPeriod(2027, 2)
+    expect(start).toBe('2027-02-01')
+    expect(end).toBe('2027-02-28')
+  })
+
+  it('handles February in a leap year', () => {
+    const { start, end } = getMonthPeriod(2028, 2)
+    expect(start).toBe('2028-02-01')
+    expect(end).toBe('2028-02-29')
+  })
+
+  it('returns correct dates for December', () => {
+    const { start, end } = getMonthPeriod(2026, 12)
+    expect(start).toBe('2026-12-01')
+    expect(end).toBe('2026-12-31')
+  })
+})
+
+describe('getQuarterPeriod', () => {
+  it('returns Q1 dates', () => {
+    const { start, end } = getQuarterPeriod(2026, 1)
+    expect(start).toBe('2026-01-01')
+    expect(end).toBe('2026-03-31')
+  })
+
+  it('returns Q2 dates', () => {
+    const { start, end } = getQuarterPeriod(2026, 2)
+    expect(start).toBe('2026-04-01')
+    expect(end).toBe('2026-06-30')
+  })
+
+  it('returns Q3 dates', () => {
+    const { start, end } = getQuarterPeriod(2026, 3)
+    expect(start).toBe('2026-07-01')
+    expect(end).toBe('2026-09-30')
+  })
+
+  it('returns Q4 dates', () => {
+    const { start, end } = getQuarterPeriod(2026, 4)
+    expect(start).toBe('2026-10-01')
+    expect(end).toBe('2026-12-31')
+  })
+})
+
+describe('getFilingDeadline', () => {
+  it('returns 25th of following month for monthly', () => {
+    expect(getFilingDeadline(2026, 1)).toBe('2026-02-25')
+    expect(getFilingDeadline(2026, 6)).toBe('2026-07-25')
+  })
+
+  it('rolls over to next year for December', () => {
+    expect(getFilingDeadline(2026, 12)).toBe('2027-01-25')
+  })
+
+  it('returns correct deadline for quarterly', () => {
+    expect(getFilingDeadline(2026, undefined, 1)).toBe('2026-04-25')
+    expect(getFilingDeadline(2026, undefined, 2)).toBe('2026-07-25')
+    expect(getFilingDeadline(2026, undefined, 3)).toBe('2026-10-25')
+  })
+
+  it('rolls over to next year for Q4', () => {
+    expect(getFilingDeadline(2026, undefined, 4)).toBe('2027-01-25')
+  })
+
+  it('throws when neither month nor quarter provided', () => {
+    expect(() => getFilingDeadline(2026)).toThrow()
+  })
+})
+
+describe('daysUntilDeadline', () => {
+  it('returns positive number for future deadlines', () => {
+    const future = new Date()
+    future.setDate(future.getDate() + 10)
+    const dateStr = future.toISOString().slice(0, 10)
+    expect(daysUntilDeadline(dateStr)).toBe(10)
+  })
+
+  it('returns 0 for today', () => {
+    const today = new Date().toISOString().slice(0, 10)
+    expect(daysUntilDeadline(today)).toBe(0)
+  })
+
+  it('returns negative number for past deadlines', () => {
+    const past = new Date()
+    past.setDate(past.getDate() - 5)
+    const dateStr = past.toISOString().slice(0, 10)
+    expect(daysUntilDeadline(dateStr)).toBe(-5)
+  })
+})

extensions/export/eu-sales-list/lib/__tests__/skv-xml-generator.test.ts

@@ -0,0 +1,189 @@
+import { describe, it, expect } from 'vitest'
+import { generateSKVXml, generateXMLFilename } from '../skv-xml-generator'
+import type { ECSalesListReport } from '../eu-sales-list-engine'
+
+function makeReport(overrides: Partial<ECSalesListReport> = {}): ECSalesListReport {
+  return {
+    period: { year: 2026, quarter: 1 },
+    filingType: 'quarterly',
+    reporterVatNumber: 'SE556677889901',
+    reporterName: 'Test AB',
+    lines: [
+      {
+        customerVatNumber: 'DE123456789',
+        customerName: 'Acme GmbH',
+        customerCountry: 'DE',
+        customerId: 'cust-1',
+        goodsAmount: 50000,
+        servicesAmount: 30000,
+        triangulationAmount: 0,
+        invoiceCount: 3,
+      },
+    ],
+    totals: { goods: 50000, services: 30000, triangulation: 0, total: 80000 },
+    warnings: [],
+    crossCheck: null,
+    invoiceCount: 3,
+    customerCount: 1,
+    ...overrides,
+  }
+}
+
+describe('generateSKVXml', () => {
+  it('starts with XML declaration', () => {
+    const xml = generateSKVXml(makeReport())
+    expect(xml).toMatch(/^<\?xml version="1\.0" encoding="UTF-8"\?>/)
+  })
+
+  it('wraps content in KVPS root element', () => {
+    const xml = generateSKVXml(makeReport())
+    expect(xml).toContain('<KVPS>')
+    expect(xml).toContain('</KVPS>')
+  })
+
+  it('includes reporter VAT number', () => {
+    const xml = generateSKVXml(makeReport())
+    expect(xml).toContain('<Momsregistreringsnummer>SE556677889901</Momsregistreringsnummer>')
+  })
+
+  it('includes reporter name', () => {
+    const xml = generateSKVXml(makeReport())
+    expect(xml).toContain('<Namn>Test AB</Namn>')
+  })
+
+  it('includes quarterly period info', () => {
+    const xml = generateSKVXml(makeReport())
+    expect(xml).toContain('<Ar>2026</Ar>')
+    expect(xml).toContain('<Kvartal>1</Kvartal>')
+    expect(xml).toContain('<Redovisningstyp>Kvartal</Redovisningstyp>')
+  })
+
+  it('includes monthly period info', () => {
+    const report = makeReport({ period: { year: 2026, month: 3 }, filingType: 'monthly' })
+    const xml = generateSKVXml(report)
+    expect(xml).toContain('<Manad>03</Manad>')
+    expect(xml).toContain('<Redovisningstyp>Manad</Redovisningstyp>')
+  })
+
+  it('includes customer line with goods and services', () => {
+    const xml = generateSKVXml(makeReport())
+    expect(xml).toContain('<KopareVATnr>DE123456789</KopareVATnr>')
+    expect(xml).toContain('<KopareLand>DE</KopareLand>')
+    expect(xml).toContain('<VarorBeloppSEK>50000</VarorBeloppSEK>')
+    expect(xml).toContain('<TjansterBeloppSEK>30000</TjansterBeloppSEK>')
+  })
+
+  it('omits zero amount elements', () => {
+    const xml = generateSKVXml(makeReport())
+    // Triangulation is 0, should not appear in line
+    expect(xml).not.toContain('<TriangelhandelBeloppSEK>0</TriangelhandelBeloppSEK>')
+  })
+
+  it('includes triangulation when non-zero', () => {
+    const report = makeReport({
+      lines: [{
+        customerVatNumber: 'DE123',
+        customerName: 'Test',
+        customerCountry: 'DE',
+        customerId: 'c-1',
+        goodsAmount: 0,
+        servicesAmount: 0,
+        triangulationAmount: 15000,
+        invoiceCount: 1,
+      }],
+    })
+
+    const xml = generateSKVXml(report)
+    expect(xml).toContain('<TriangelhandelBeloppSEK>15000</TriangelhandelBeloppSEK>')
+  })
+
+  it('skips lines with all zero amounts', () => {
+    const report = makeReport({
+      lines: [
+        {
+          customerVatNumber: 'DE111',
+          customerName: 'Zero',
+          customerCountry: 'DE',
+          customerId: 'c-1',
+          goodsAmount: 0,
+          servicesAmount: 0,
+          triangulationAmount: 0,
+          invoiceCount: 0,
+        },
+        {
+          customerVatNumber: 'FR222',
+          customerName: 'NonZero',
+          customerCountry: 'FR',
+          customerId: 'c-2',
+          goodsAmount: 10000,
+          servicesAmount: 0,
+          triangulationAmount: 0,
+          invoiceCount: 1,
+        },
+      ],
+    })
+
+    const xml = generateSKVXml(report)
+    expect(xml).not.toContain('DE111')
+    expect(xml).toContain('FR222')
+  })
+
+  it('includes totals section', () => {
+    const xml = generateSKVXml(makeReport())
+    expect(xml).toContain('<VarorTotaltSEK>50000</VarorTotaltSEK>')
+    expect(xml).toContain('<TjansterTotaltSEK>30000</TjansterTotaltSEK>')
+    expect(xml).toContain('<TotaltSEK>80000</TotaltSEK>')
+  })
+
+  it('rounds amounts to whole SEK', () => {
+    const report = makeReport({
+      lines: [{
+        customerVatNumber: 'DE123',
+        customerName: 'Test',
+        customerCountry: 'DE',
+        customerId: 'c-1',
+        goodsAmount: 12345.67,
+        servicesAmount: 0,
+        triangulationAmount: 0,
+        invoiceCount: 1,
+      }],
+      totals: { goods: 12345.67, services: 0, triangulation: 0, total: 12345.67 },
+    })
+
+    const xml = generateSKVXml(report)
+    expect(xml).toContain('<VarorBeloppSEK>12346</VarorBeloppSEK>')
+  })
+
+  it('escapes XML special characters in names', () => {
+    const report = makeReport({
+      reporterName: 'Foo & Bar <AB>',
+      lines: [{
+        customerVatNumber: 'DE123',
+        customerName: 'Test',
+        customerCountry: 'DE',
+        customerId: 'c-1',
+        goodsAmount: 1000,
+        servicesAmount: 0,
+        triangulationAmount: 0,
+        invoiceCount: 1,
+      }],
+    })
+
+    const xml = generateSKVXml(report)
+    expect(xml).toContain('Foo &amp; Bar &lt;AB&gt;')
+    expect(xml).not.toContain('Foo & Bar <AB>')
+  })
+})
+
+describe('generateXMLFilename', () => {
+  it('generates quarterly filename', () => {
+    const filename = generateXMLFilename(makeReport())
+    expect(filename).toBe('KVPS_SE556677889901_2026-Q1.xml')
+  })
+
+  it('generates monthly filename', () => {
+    const report = makeReport({ period: { year: 2026, month: 11 }, filingType: 'monthly' })
+    const filename = generateXMLFilename(report)
+    expect(filename).toBe('KVPS_SE556677889901_2026-11.xml')
+  })
+})

extensions/export/eu-sales-list/lib/csv-generator.ts

@@ -0,0 +1,65 @@
+/**
+ * EU Sales List CSV Generator
+ *
+ * Generates a semicolon-separated CSV file (UTF-8 with BOM) for the
+ * periodisk sammanställning report. Compatible with Excel and Skatteverket's
+ * import tools.
+ *
+ * Format: Semicolon-delimited, UTF-8 BOM, whole SEK amounts.
+ */
+
+import type { ECSalesListReport } from './eu-sales-list-engine'
+
+/** UTF-8 BOM for Excel compatibility */
+const UTF8_BOM = '\uFEFF'
+
+/**
+ * Generate a CSV string for the EC Sales List report.
+ *
+ * Columns:
+ *   Land;VAT-nummer;Varuförsäljning (SEK);Tjänsteförsäljning (SEK);Trepartshandel (SEK)
+ *
+ * Amounts are rounded to whole SEK (öre removed) as required by Skatteverket.
+ */
+export function generateCSV(report: ECSalesListReport): string {
+  const header = 'Land;VAT-nummer;Varuförsäljning (SEK);Tjänsteförsäljning (SEK);Trepartshandel (SEK)'
+
+  const rows = report.lines.map(line => {
+    const goods = Math.round(line.goodsAmount)
+    const services = Math.round(line.servicesAmount)
+    const triangulation = Math.round(line.triangulationAmount)
+    return `${line.customerCountry};${line.customerVatNumber};${goods};${services};${triangulation}`
+  })
+
+  // Summary row
+  const totalGoods = Math.round(report.totals.goods)
+  const totalServices = Math.round(report.totals.services)
+  const totalTriangulation = Math.round(report.totals.triangulation)
+  rows.push('')
+  rows.push(`Summa;;${totalGoods};${totalServices};${totalTriangulation}`)
+
+  return UTF8_BOM + [header, ...rows].join('\r\n') + '\r\n'
+}
+
+/**
+ * Generate a filename for the CSV download.
+ *
+ * Format: PS_<VAT>_<period>.csv
+ * Example: PS_SE556677889901_2026-Q1.csv or PS_SE556677889901_2026-03.csv
+ */
+export function generateCSVFilename(report: ECSalesListReport): string {
+  const vat = report.reporterVatNumber.replace(/\s/g, '')
+  const period = formatPeriod(report)
+  return `PS_${vat}_${period}.csv`
+}
+
+function formatPeriod(report: ECSalesListReport): string {
+  const { year, month, quarter } = report.period
+  if (month !== undefined) {
+    return `${year}-${String(month).padStart(2, '0')}`
+  }
+  if (quarter !== undefined) {
+    return `${year}-Q${quarter}`
+  }
+  return `${year}`
+}

extensions/export/eu-sales-list/lib/eu-sales-list-engine.ts

@@ -0,0 +1,453 @@
+/**
+ * EU Sales List / Periodisk Sammanställning Engine
+ *
+ * Core business logic for generating EC Sales List reports.
+ * Pure functions — no Supabase, no React, no side effects.
+ *
+ * Aggregates intra-community B2B sales by customer VAT number,
+ * separating goods (account 3108, box 35) from services (account 3308, box 39).
+ *
+ * Reference: Skatteverket SKV 5740
+ * Filing: Monthly for goods, quarterly for services
+ * Deadline: 25th of the month following the reporting period
+ */
+
+import { isEUCountry, toCountryCode } from '@/extensions/export/shared/eu-countries'
+
+// ── Types ────────────────────────────────────────────────────
+
+/** Invoice data needed for EC Sales List generation */
+export interface ECSalesListInvoice {
+  id: string
+  invoice_number: string
+  invoice_date: string
+  status: string
+  currency: string
+  total: number
+  total_sek: number | null
+  subtotal: number
+  subtotal_sek: number | null
+  vat_treatment: string
+  moms_ruta: string | null
+  document_type: string
+  credited_invoice_id: string | null
+  customer_id: string
+}
+
+/** Customer data needed for EC Sales List */
+export interface ECSalesListCustomer {
+  id: string
+  name: string
+  country: string
+  customer_type: string
+  vat_number: string | null
+  vat_number_validated: boolean
+}
+
+/** Journal entry line data for cross-checking */
+export interface GLAccountTotal {
+  account_number: string
+  credit: number
+}
+
+/** Aggregated line in the EC Sales List report */
+export interface ECSalesListLine {
+  customerVatNumber: string
+  customerName: string
+  customerCountry: string
+  customerId: string
+  goodsAmount: number
+  servicesAmount: number
+  triangulationAmount: number
+  invoiceCount: number
+}
+
+/** Warning about data quality */
+export interface ECSalesListWarning {
+  type:
+    | 'missing_vat_number'
+    | 'unvalidated_vat_number'
+    | 'missing_moms_ruta'
+    | 'non_eu_country'
+    | 'cross_check_mismatch'
+  severity: 'error' | 'warning'
+  invoiceId?: string
+  invoiceNumber?: string
+  customerId?: string
+  customerName?: string
+  message: string
+}
+
+/** Cross-check result comparing report totals vs GL */
+export interface CrossCheckResult {
+  box35Match: boolean
+  box35ReportTotal: number
+  box35GLTotal: number
+  box39Match: boolean
+  box39ReportTotal: number
+  box39GLTotal: number
+}
+
+/** Complete EC Sales List report */
+export interface ECSalesListReport {
+  period: {
+    year: number
+    month?: number
+    quarter?: number
+  }
+  filingType: 'monthly' | 'quarterly'
+  reporterVatNumber: string
+  reporterName: string
+  lines: ECSalesListLine[]
+  totals: {
+    goods: number
+    services: number
+    triangulation: number
+    total: number
+  }
+  warnings: ECSalesListWarning[]
+  crossCheck: CrossCheckResult | null
+  invoiceCount: number
+  customerCount: number
+}
+
+/** Options for generating the report */
+export interface GenerateReportOptions {
+  invoices: ECSalesListInvoice[]
+  customers: ECSalesListCustomer[]
+  glTotals?: GLAccountTotal[]
+  reporterVatNumber: string
+  reporterName: string
+  year: number
+  month?: number
+  quarter?: number
+}
+
+// ── Revenue account classification ─────────────────────────
+
+/** Accounts that represent EU goods sales (box 35) */
+const GOODS_ACCOUNTS = ['3108', '3521']
+
+/** Accounts that represent EU service sales (box 39) */
+const SERVICE_ACCOUNTS = ['3308']
+
+/** Accounts for triangular trade (box 38) */
+const TRIANGULATION_ACCOUNTS = ['3109']
+
+// ── Core engine ──────────────────────────────────────────────
+
+/**
+ * Generate an EC Sales List report from invoice and customer data.
+ *
+ * Steps:
+ * 1. Filter invoices to EU B2B reverse charge only
+ * 2. Join with customers
+ * 3. Validate data quality (VAT numbers, country codes)
+ * 4. Group by customer VAT number
+ * 5. Classify as goods or services based on moms_ruta / vat_treatment
+ * 6. Cross-check against GL account totals if provided
+ */
+export function generateECSalesListReport(options: GenerateReportOptions): ECSalesListReport {
+  const {
+    invoices,
+    customers,
+    glTotals,
+    reporterVatNumber,
+    reporterName,
+    year,
+    month,
+    quarter,
+  } = options
+
+  const warnings: ECSalesListWarning[] = []
+  const customerMap = new Map(customers.map(c => [c.id, c]))
+
+  // Step 1: Filter to relevant invoices
+  const relevantInvoices = invoices.filter(inv => {
+    // Only sent, paid, or overdue invoices (not drafts)
+    if (!['sent', 'paid', 'overdue'].includes(inv.status)) return false
+    // Only actual invoices (not proforma/delivery notes) — except credit notes
+    if (inv.document_type !== 'invoice' && inv.credited_invoice_id === null) return false
+    // Must be reverse charge (EU B2B)
+    if (inv.vat_treatment !== 'reverse_charge') return false
+    return true
+  })
+
+  // Step 2: Build aggregation map (keyed by customer VAT number)
+  const aggregation = new Map<string, ECSalesListLine>()
+
+  for (const invoice of relevantInvoices) {
+    const customer = customerMap.get(invoice.customer_id)
+    if (!customer) continue
+
+    // Validate: customer should be in an EU country (not Sweden)
+    if (!isEUCountry(customer.country)) {
+      warnings.push({
+        type: 'non_eu_country',
+        severity: 'warning',
+        invoiceId: invoice.id,
+        invoiceNumber: invoice.invoice_number,
+        customerId: customer.id,
+        customerName: customer.name,
+        message: `Faktura ${invoice.invoice_number} till ${customer.name} har omvänd skattskyldighet men kunden är i ${customer.country} (ej EU).`,
+      })
+      continue
+    }
+
+    // Validate: VAT number must exist
+    if (!customer.vat_number) {
+      warnings.push({
+        type: 'missing_vat_number',
+        severity: 'error',
+        invoiceId: invoice.id,
+        invoiceNumber: invoice.invoice_number,
+        customerId: customer.id,
+        customerName: customer.name,
+        message: `Faktura ${invoice.invoice_number} till ${customer.name} saknar momsregistreringsnummer (VAT-nummer). Krävs för periodisk sammanställning.`,
+      })
+      continue
+    }
+
+    // Validate: VAT number should be validated via VIES
+    if (!customer.vat_number_validated) {
+      warnings.push({
+        type: 'unvalidated_vat_number',
+        severity: 'warning',
+        invoiceId: invoice.id,
+        invoiceNumber: invoice.invoice_number,
+        customerId: customer.id,
+        customerName: customer.name,
+        message: `VAT-nummer ${customer.vat_number} för ${customer.name} har inte validerats via VIES.`,
+      })
+    }
+
+    // Determine amount in SEK (use total_sek if available, else total for SEK invoices)
+    const amountSek = getAmountSek(invoice)
+
+    // Determine if this is a credit note (negative amount)
+    const isCreditNote = invoice.credited_invoice_id !== null
+    const effectiveAmount = isCreditNote ? -Math.abs(amountSek) : amountSek
+
+    // Classify: goods (box 35) or services (box 39)
+    const classification = classifyInvoice(invoice)
+
+    // Normalize country to ISO code for consistent output
+    const countryCode = toCountryCode(customer.country)
+
+    // Get or create aggregation line
+    const vatNumber = customer.vat_number
+    const key = vatNumber
+    if (!aggregation.has(key)) {
+      aggregation.set(key, {
+        customerVatNumber: vatNumber,
+        customerName: customer.name,
+        customerCountry: countryCode,
+        customerId: customer.id,
+        goodsAmount: 0,
+        servicesAmount: 0,
+        triangulationAmount: 0,
+        invoiceCount: 0,
+      })
+    }
+
+    const line = aggregation.get(key)!
+    line.invoiceCount++
+
+    if (classification === 'triangulation') {
+      line.triangulationAmount = round2(line.triangulationAmount + effectiveAmount)
+    } else if (classification === 'goods') {
+      line.goodsAmount = round2(line.goodsAmount + effectiveAmount)
+    } else {
+      line.servicesAmount = round2(line.servicesAmount + effectiveAmount)
+    }
+  }
+
+  // Step 3: Build sorted output
+  const lines = Array.from(aggregation.values())
+    .sort((a, b) => a.customerCountry.localeCompare(b.customerCountry) || a.customerVatNumber.localeCompare(b.customerVatNumber))
+
+  // Step 4: Calculate totals
+  const totals = {
+    goods: round2(lines.reduce((sum, l) => sum + l.goodsAmount, 0)),
+    services: round2(lines.reduce((sum, l) => sum + l.servicesAmount, 0)),
+    triangulation: round2(lines.reduce((sum, l) => sum + l.triangulationAmount, 0)),
+    total: 0,
+  }
+  totals.total = round2(totals.goods + totals.services + totals.triangulation)
+
+  // Step 5: Cross-check against GL if data provided
+  let crossCheck: CrossCheckResult | null = null
+  if (glTotals && glTotals.length > 0) {
+    crossCheck = performCrossCheck(totals, glTotals, warnings)
+  }
+
+  return {
+    period: { year, month, quarter },
+    filingType: month !== undefined ? 'monthly' : 'quarterly',
+    reporterVatNumber,
+    reporterName,
+    lines,
+    totals,
+    warnings,
+    crossCheck,
+    invoiceCount: relevantInvoices.length,
+    customerCount: lines.length,
+  }
+}
+
+// ── Classification helpers ───────────────────────────────────
+
+type InvoiceClassification = 'goods' | 'services' | 'triangulation'
+
+/**
+ * Classify an invoice as goods, services, or triangulation.
+ *
+ * Uses moms_ruta as primary signal (most reliable, set during invoice creation).
+ * Falls back to vat_treatment if moms_ruta is not set.
+ *
+ * Box 35 = goods to EU (account 3108)
+ * Box 38 = triangular trade (account 3109)
+ * Box 39 = services to EU (account 3308)
+ */
+function classifyInvoice(invoice: ECSalesListInvoice): InvoiceClassification {
+  const ruta = invoice.moms_ruta
+
+  if (ruta === '35') return 'goods'
+  if (ruta === '38') return 'triangulation'
+  if (ruta === '39') return 'services'
+
+  // Fallback: EU B2B reverse charge defaults to services (box 39)
+  // since the current VAT rules assign '39' for all reverse charge.
+  // Goods classification requires explicit moms_ruta = '35'.
+  return 'services'
+}
+
+// ── Cross-check ──────────────────────────────────────────────
+
+/**
+ * Compare report totals against GL account credit totals.
+ *
+ * Box 35 total should match credit sum on accounts 3108 + 3521
+ * Box 39 total should match credit sum on account 3308
+ *
+ * A tolerance of 1 SEK is allowed for rounding differences.
+ */
+function performCrossCheck(
+  totals: { goods: number; services: number },
+  glTotals: GLAccountTotal[],
+  warnings: ECSalesListWarning[]
+): CrossCheckResult {
+  const glMap = new Map(glTotals.map(t => [t.account_number, t.credit]))
+
+  const box35GL = round2(
+    GOODS_ACCOUNTS.reduce((sum, acc) => sum + (glMap.get(acc) ?? 0), 0)
+  )
+  const box39GL = round2(
+    SERVICE_ACCOUNTS.reduce((sum, acc) => sum + (glMap.get(acc) ?? 0), 0)
+  )
+
+  const TOLERANCE = 1 // Allow 1 SEK rounding difference
+  const box35Match = Math.abs(totals.goods - box35GL) <= TOLERANCE
+  const box39Match = Math.abs(totals.services - box39GL) <= TOLERANCE
+
+  if (!box35Match) {
+    warnings.push({
+      type: 'cross_check_mismatch',
+      severity: 'warning',
+      message: `Ruta 35 (varuförsäljning EU): rapporten visar ${totals.goods} SEK men huvudboken visar ${box35GL} SEK (differens ${round2(totals.goods - box35GL)} SEK).`,
+    })
+  }
+
+  if (!box39Match) {
+    warnings.push({
+      type: 'cross_check_mismatch',
+      severity: 'warning',
+      message: `Ruta 39 (tjänsteförsäljning EU): rapporten visar ${totals.services} SEK men huvudboken visar ${box39GL} SEK (differens ${round2(totals.services - box39GL)} SEK).`,
+    })
+  }
+
+  return {
+    box35Match,
+    box35ReportTotal: totals.goods,
+    box35GLTotal: box35GL,
+    box39Match,
+    box39ReportTotal: totals.services,
+    box39GLTotal: box39GL,
+  }
+}
+
+// ── Amount helpers ───────────────────────────────────────────
+
+/**
+ * Get the SEK amount for an invoice.
+ * Uses subtotal_sek (excluding VAT) for the EC Sales List,
+ * since reverse charge invoices have 0 VAT and subtotal === total.
+ * Falls back to subtotal if SEK amounts are not populated.
+ */
+function getAmountSek(invoice: ECSalesListInvoice): number {
+  // For reverse charge invoices, subtotal_sek is the correct base
+  if (invoice.subtotal_sek !== null) return round2(invoice.subtotal_sek)
+  // If no SEK conversion exists, the invoice is already in SEK
+  return round2(invoice.subtotal)
+}
+
+/** Round to 2 decimal places (monetary standard) */
+function round2(value: number): number {
+  return Math.round(value * 100) / 100
+}
+
+// ── Period helpers ───────────────────────────────────────────
+
+/** Get the start and end dates for a monthly period */
+export function getMonthPeriod(year: number, month: number): { start: string; end: string } {
+  const start = `${year}-${String(month).padStart(2, '0')}-01`
+  const lastDay = new Date(year, month, 0).getDate()
+  const end = `${year}-${String(month).padStart(2, '0')}-${String(lastDay).padStart(2, '0')}`
+  return { start, end }
+}
+
+/** Get the start and end dates for a quarterly period */
+export function getQuarterPeriod(year: number, quarter: number): { start: string; end: string } {
+  const startMonth = (quarter - 1) * 3 + 1
+  const endMonth = startMonth + 2
+  const start = `${year}-${String(startMonth).padStart(2, '0')}-01`
+  const lastDay = new Date(year, endMonth, 0).getDate()
+  const end = `${year}-${String(endMonth).padStart(2, '0')}-${String(lastDay).padStart(2, '0')}`
+  return { start, end }
+}
+
+/** Get the filing deadline for a period (25th of the month after period end) */
+export function getFilingDeadline(year: number, month?: number, quarter?: number): string {
+  let deadlineMonth: number
+  let deadlineYear = year
+
+  if (month !== undefined) {
+    // Monthly filing: due 25th of the following month
+    deadlineMonth = month + 1
+    if (deadlineMonth > 12) {
+      deadlineMonth = 1
+      deadlineYear++
+    }
+  } else if (quarter !== undefined) {
+    // Quarterly filing: due 25th of the month after quarter end
+    deadlineMonth = quarter * 3 + 1
+    if (deadlineMonth > 12) {
+      deadlineMonth = 1
+      deadlineYear++
+    }
+  } else {
+    throw new Error('Either month or quarter must be provided')
+  }
+
+  return `${deadlineYear}-${String(deadlineMonth).padStart(2, '0')}-25`
+}
+
+/** Calculate days remaining until a deadline */
+export function daysUntilDeadline(deadline: string): number {
+  const deadlineDate = new Date(deadline)
+  const today = new Date()
+  today.setHours(0, 0, 0, 0)
+  deadlineDate.setHours(0, 0, 0, 0)
+  const diffMs = deadlineDate.getTime() - today.getTime()
+  return Math.ceil(diffMs / (1000 * 60 * 60 * 24))
+}

extensions/export/eu-sales-list/lib/skv-xml-generator.ts

@@ -0,0 +1,127 @@
+/**
+ * EU Sales List XML Generator (SKV 5740 format)
+ *
+ * Generates XML compatible with Skatteverket's e-filing system for
+ * periodisk sammanställning (EC Sales List / recapitulative statement).
+ *
+ * Reference: Skatteverket SKV 5740, KVPS XML schema
+ * Filing: Monthly for goods, quarterly for services
+ *
+ * The XML structure follows Skatteverket's KVPS (Kvartalsvis Periodisk
+ * Sammanställning) format with elements for reporter info, period, and
+ * per-customer goods/services/triangulation amounts in whole SEK.
+ */
+
+import type { ECSalesListReport } from './eu-sales-list-engine'
+
+/**
+ * Generate SKV-compatible XML for the EC Sales List report.
+ *
+ * Structure:
+ *   <KVPS>
+ *     <Avsandare>         — reporter/sender information
+ *     <Period>            — reporting period
+ *     <Rad>               — one per customer VAT number
+ *       <KopareVATnr>     — buyer VAT number
+ *       <KopareLand>      — buyer country code
+ *       <VarorBeloppSEK>  — goods amount (box 35)
+ *       <TjansterBeloppSEK> — services amount (box 39)
+ *       <TriangelhandelBeloppSEK> — triangulation (box 38)
+ *     </Rad>
+ *   </KVPS>
+ *
+ * All amounts are rounded to whole SEK (no decimals).
+ */
+export function generateSKVXml(report: ECSalesListReport): string {
+  const lines: string[] = []
+
+  lines.push('<?xml version="1.0" encoding="UTF-8"?>')
+  lines.push('<KVPS>')
+
+  // Reporter/sender info
+  lines.push('  <Avsandare>')
+  lines.push(`    <Momsregistreringsnummer>${escapeXml(report.reporterVatNumber)}</Momsregistreringsnummer>`)
+  lines.push(`    <Namn>${escapeXml(report.reporterName)}</Namn>`)
+  lines.push('  </Avsandare>')
+
+  // Period info
+  lines.push('  <Period>')
+  lines.push(`    <Ar>${report.period.year}</Ar>`)
+  if (report.period.month !== undefined) {
+    lines.push(`    <Manad>${String(report.period.month).padStart(2, '0')}</Manad>`)
+  }
+  if (report.period.quarter !== undefined) {
+    lines.push(`    <Kvartal>${report.period.quarter}</Kvartal>`)
+  }
+  lines.push(`    <Redovisningstyp>${report.filingType === 'monthly' ? 'Manad' : 'Kvartal'}</Redovisningstyp>`)
+  lines.push('  </Period>')
+
+  // Customer lines
+  for (const line of report.lines) {
+    const goods = Math.round(line.goodsAmount)
+    const services = Math.round(line.servicesAmount)
+    const triangulation = Math.round(line.triangulationAmount)
+
+    // Skip lines with all zero amounts
+    if (goods === 0 && services === 0 && triangulation === 0) continue
+
+    lines.push('  <Rad>')
+    lines.push(`    <KopareVATnr>${escapeXml(line.customerVatNumber)}</KopareVATnr>`)
+    lines.push(`    <KopareLand>${escapeXml(line.customerCountry)}</KopareLand>`)
+    if (goods !== 0) {
+      lines.push(`    <VarorBeloppSEK>${goods}</VarorBeloppSEK>`)
+    }
+    if (services !== 0) {
+      lines.push(`    <TjansterBeloppSEK>${services}</TjansterBeloppSEK>`)
+    }
+    if (triangulation !== 0) {
+      lines.push(`    <TriangelhandelBeloppSEK>${triangulation}</TriangelhandelBeloppSEK>`)
+    }
+    lines.push('  </Rad>')
+  }
+
+  // Totals
+  lines.push('  <Summa>')
+  lines.push(`    <VarorTotaltSEK>${Math.round(report.totals.goods)}</VarorTotaltSEK>`)
+  lines.push(`    <TjansterTotaltSEK>${Math.round(report.totals.services)}</TjansterTotaltSEK>`)
+  lines.push(`    <TriangelhandelTotaltSEK>${Math.round(report.totals.triangulation)}</TriangelhandelTotaltSEK>`)
+  lines.push(`    <TotaltSEK>${Math.round(report.totals.total)}</TotaltSEK>`)
+  lines.push('  </Summa>')
+
+  lines.push('</KVPS>')
+
+  return lines.join('\n') + '\n'
+}
+
+/**
+ * Generate a filename for the XML download.
+ *
+ * Format: KVPS_<VAT>_<period>.xml
+ * Example: KVPS_SE556677889901_2026-Q1.xml
+ */
+export function generateXMLFilename(report: ECSalesListReport): string {
+  const vat = report.reporterVatNumber.replace(/\s/g, '')
+  const period = formatPeriod(report)
+  return `KVPS_${vat}_${period}.xml`
+}
+
+function formatPeriod(report: ECSalesListReport): string {
+  const { year, month, quarter } = report.period
+  if (month !== undefined) {
+    return `${year}-${String(month).padStart(2, '0')}`
+  }
+  if (quarter !== undefined) {
+    return `${year}-Q${quarter}`
+  }
+  return `${year}`
+}
+
+/** Escape special XML characters to prevent injection */
+function escapeXml(str: string): string {
+  return str
+    .replace(/&/g, '&amp;')
+    .replace(/</g, '&lt;')
+    .replace(/>/g, '&gt;')
+    .replace(/"/g, '&quot;')
+    .replace(/'/g, '&apos;')
+}

extensions/export/intrastat/index.ts

@@ -0,0 +1,17 @@
+import type { Extension } from '@/lib/extensions/types'
+
+/**
+ * Intrastat Generator Extension
+ *
+ * Generates monthly Intrastat dispatch declarations for reporting to SCB
+ * (Statistics Sweden). Manages product metadata (CN commodity codes, weights,
+ * country of origin) and aggregates EU goods dispatches.
+ *
+ * Outputs SCB IDEP.web compatible CSV files. Monitors the SEK 12M dispatch
+ * threshold and alerts when the reporting obligation is triggered.
+ */
+export const intrastatExtension: Extension = {
+  id: 'intrastat',
+  name: 'Intrastat-generator',
+  version: '1.0.0',
+}

extensions/export/intrastat/lib/__tests__/intrastat-engine.test.ts

@@ -0,0 +1,417 @@
+import { describe, it, expect } from 'vitest'
+import {
+  generateIntrastatReport,
+  getIntrastatDeadline,
+  type IntrastatInvoice,
+  type IntrastatCustomer,
+  type IntrastatInvoiceItem,
+  type ProductMetadata,
+  type IntrastatOptions,
+} from '../intrastat-engine'
+
+// ── Fixtures ────────────────────────────────────────────────
+
+function makeInvoice(overrides: Partial<IntrastatInvoice> = {}): IntrastatInvoice {
+  return {
+    id: 'inv-1',
+    invoice_number: 'F2026-001',
+    invoice_date: '2026-01-15',
+    status: 'sent',
+    vat_treatment: 'reverse_charge',
+    moms_ruta: '35',
+    currency: 'EUR',
+    total_sek: 100000,
+    subtotal_sek: 100000,
+    subtotal: 9000,
+    document_type: 'invoice',
+    credited_invoice_id: null,
+    customer_id: 'cust-1',
+    ...overrides,
+  }
+}
+
+function makeCustomer(overrides: Partial<IntrastatCustomer> = {}): IntrastatCustomer {
+  return {
+    id: 'cust-1',
+    name: 'Acme GmbH',
+    country: 'DE',
+    vat_number: 'DE123456789',
+    ...overrides,
+  }
+}
+
+function makeItem(overrides: Partial<IntrastatInvoiceItem> = {}): IntrastatInvoiceItem {
+  return {
+    id: 'item-1',
+    invoice_id: 'inv-1',
+    description: 'Stålbalk M8',
+    quantity: 100,
+    unit_price: 90,
+    total: 9000,
+    total_sek: 100000,
+    ...overrides,
+  }
+}
+
+function makeProduct(overrides: Partial<ProductMetadata> = {}): ProductMetadata {
+  return {
+    productId: 'stålbalk m8',
+    cnCode: '72163100',
+    description: 'Stålbalk M8',
+    netWeightKg: 45.5,
+    countryOfOrigin: 'SE',
+    supplementaryUnit: null,
+    supplementaryUnitType: null,
+    ...overrides,
+  }
+}
+
+const BASE_OPTIONS: IntrastatOptions = {
+  invoices: [],
+  invoiceItems: [],
+  customers: [],
+  products: [],
+  reporterVatNumber: 'SE556677889901',
+  reporterName: 'Test AB',
+  year: 2026,
+  month: 1,
+}
+
+// ── Basic report tests ──────────────────────────────────────
+
+describe('generateIntrastatReport', () => {
+  it('generates empty report when no invoices', () => {
+    const report = generateIntrastatReport(BASE_OPTIONS)
+
+    expect(report.lines).toHaveLength(0)
+    expect(report.totals.invoicedValue).toBe(0)
+    expect(report.totals.netMass).toBe(0)
+    expect(report.invoiceCount).toBe(0)
+    expect(report.flowType).toBe('dispatch')
+  })
+
+  it('generates line from matched invoice + product', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      invoiceItems: [makeItem()],
+      customers: [makeCustomer()],
+      products: [makeProduct()],
+    })
+
+    expect(report.lines).toHaveLength(1)
+    expect(report.lines[0].cnCode).toBe('72163100')
+    expect(report.lines[0].partnerCountry).toBe('DE')
+    expect(report.lines[0].countryOfOrigin).toBe('SE')
+    expect(report.lines[0].invoicedValue).toBe(100000)
+    expect(report.lines[0].netMass).toBe(4550) // 45.5 kg × 100 units
+    expect(report.lines[0].partnerVatId).toBe('DE123456789')
+  })
+
+  it('aggregates multiple invoices with same CN code + country', () => {
+    const invoices = [
+      makeInvoice({ id: 'inv-1', subtotal_sek: 50000, total_sek: 50000 }),
+      makeInvoice({ id: 'inv-2', subtotal_sek: 30000, total_sek: 30000 }),
+    ]
+    const items = [
+      makeItem({ id: 'item-1', invoice_id: 'inv-1', total_sek: 50000, quantity: 50 }),
+      makeItem({ id: 'item-2', invoice_id: 'inv-2', total_sek: 30000, quantity: 30 }),
+    ]
+
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices,
+      invoiceItems: items,
+      customers: [makeCustomer()],
+      products: [makeProduct()],
+    })
+
+    expect(report.lines).toHaveLength(1)
+    expect(report.lines[0].invoicedValue).toBe(80000)
+    expect(report.lines[0].netMass).toBe(3640) // 45.5 × (50 + 30)
+    expect(report.invoiceCount).toBe(2)
+  })
+
+  it('separates lines by different partner countries', () => {
+    const invoices = [
+      makeInvoice({ id: 'inv-1', customer_id: 'cust-1' }),
+      makeInvoice({ id: 'inv-2', customer_id: 'cust-2' }),
+    ]
+    const items = [
+      makeItem({ id: 'item-1', invoice_id: 'inv-1', quantity: 10 }),
+      makeItem({ id: 'item-2', invoice_id: 'inv-2', quantity: 20 }),
+    ]
+    const customers = [
+      makeCustomer({ id: 'cust-1', country: 'DE' }),
+      makeCustomer({ id: 'cust-2', country: 'FI', vat_number: 'FI12345678', name: 'Finnish Co' }),
+    ]
+
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices,
+      invoiceItems: items,
+      customers,
+      products: [makeProduct()],
+    })
+
+    expect(report.lines).toHaveLength(2)
+    expect(report.lines[0].partnerCountry).toBe('DE')
+    expect(report.lines[1].partnerCountry).toBe('FI')
+  })
+
+  it('separates lines by different CN codes', () => {
+    const items = [
+      makeItem({ id: 'item-1', invoice_id: 'inv-1', description: 'Stålbalk M8', quantity: 10, total_sek: 50000 }),
+      makeItem({ id: 'item-2', invoice_id: 'inv-1', description: 'Ventil DN50', quantity: 5, total_sek: 50000 }),
+    ]
+    const products = [
+      makeProduct({ productId: 'stålbalk m8', cnCode: '72163100', description: 'Stålbalk M8' }),
+      makeProduct({ productId: 'ventil dn50', cnCode: '84818019', description: 'Ventil DN50', netWeightKg: 2.3 }),
+    ]
+
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      invoiceItems: items,
+      customers: [makeCustomer()],
+      products,
+    })
+
+    expect(report.lines).toHaveLength(2)
+    const codes = report.lines.map(l => l.cnCode).sort()
+    expect(codes).toEqual(['72163100', '84818019'])
+  })
+
+  // ── Credit notes ──────────────────────────────────────────
+
+  it('handles credit notes (subtracts from totals)', () => {
+    const invoices = [
+      makeInvoice({ id: 'inv-1', subtotal_sek: 100000, total_sek: 100000 }),
+      makeInvoice({
+        id: 'inv-2',
+        subtotal_sek: 20000,
+        total_sek: 20000,
+        credited_invoice_id: 'inv-1',
+      }),
+    ]
+    const items = [
+      makeItem({ id: 'item-1', invoice_id: 'inv-1', total_sek: 100000, quantity: 100 }),
+      makeItem({ id: 'item-2', invoice_id: 'inv-2', total_sek: 20000, quantity: 20 }),
+    ]
+
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices,
+      invoiceItems: items,
+      customers: [makeCustomer()],
+      products: [makeProduct()],
+    })
+
+    expect(report.lines[0].invoicedValue).toBe(80000)
+    expect(report.lines[0].netMass).toBe(3640) // 45.5 × (100 - 20)
+  })
+
+  // ── Filtering ─────────────────────────────────────────────
+
+  it('excludes non-reverse-charge invoices', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ vat_treatment: 'standard_25' })],
+      invoiceItems: [makeItem()],
+      customers: [makeCustomer()],
+      products: [makeProduct()],
+    })
+
+    expect(report.lines).toHaveLength(0)
+  })
+
+  it('excludes services (moms_ruta 39)', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ moms_ruta: '39' })],
+      invoiceItems: [makeItem()],
+      customers: [makeCustomer()],
+      products: [makeProduct()],
+    })
+
+    expect(report.lines).toHaveLength(0)
+  })
+
+  it('excludes non-EU countries', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      invoiceItems: [makeItem()],
+      customers: [makeCustomer({ country: 'US' })],
+      products: [makeProduct()],
+    })
+
+    expect(report.lines).toHaveLength(0)
+  })
+
+  it('excludes Sweden', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      invoiceItems: [makeItem()],
+      customers: [makeCustomer({ country: 'SE' })],
+      products: [makeProduct()],
+    })
+
+    expect(report.lines).toHaveLength(0)
+  })
+
+  it('excludes draft invoices', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ status: 'draft' })],
+      invoiceItems: [makeItem()],
+      customers: [makeCustomer()],
+      products: [makeProduct()],
+    })
+
+    expect(report.lines).toHaveLength(0)
+  })
+
+  // ── Warnings ──────────────────────────────────────────────
+
+  it('warns when product has no CN code', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      invoiceItems: [makeItem()],
+      customers: [makeCustomer()],
+      products: [makeProduct({ cnCode: null })],
+    })
+
+    const cnWarnings = report.warnings.filter(w => w.type === 'missing_cn_code')
+    expect(cnWarnings.length).toBeGreaterThan(0)
+  })
+
+  it('warns when product has no weight', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      invoiceItems: [makeItem()],
+      customers: [makeCustomer()],
+      products: [makeProduct({ netWeightKg: null })],
+    })
+
+    const weightWarnings = report.warnings.filter(w => w.type === 'missing_weight')
+    expect(weightWarnings.length).toBeGreaterThan(0)
+  })
+
+  it('warns when no product match found for invoice line', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      invoiceItems: [makeItem({ description: 'Unknown Product XYZ' })],
+      customers: [makeCustomer()],
+      products: [makeProduct()], // won't match 'Unknown Product XYZ'
+    })
+
+    const cnWarnings = report.warnings.filter(w => w.type === 'missing_cn_code')
+    expect(cnWarnings.length).toBeGreaterThan(0)
+  })
+
+  // ── Threshold ─────────────────────────────────────────────
+
+  it('calculates threshold status with prior cumulative', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ subtotal_sek: 500000 })],
+      invoiceItems: [makeItem({ total_sek: 500000 })],
+      customers: [makeCustomer()],
+      products: [makeProduct()],
+      priorCumulativeValue: 11_000_000,
+    })
+
+    expect(report.thresholdStatus.cumulativeValue).toBe(11_500_000)
+    expect(report.thresholdStatus.isObligated).toBe(false)
+    expect(report.thresholdStatus.percentageUsed).toBeCloseTo(95.83, 1)
+  })
+
+  it('flags when threshold is exceeded', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ subtotal_sek: 2_000_000 })],
+      invoiceItems: [makeItem({ total_sek: 2_000_000 })],
+      customers: [makeCustomer()],
+      products: [makeProduct()],
+      priorCumulativeValue: 11_000_000,
+    })
+
+    expect(report.thresholdStatus.isObligated).toBe(true)
+    const thresholdWarnings = report.warnings.filter(w => w.type === 'threshold_exceeded')
+    expect(thresholdWarnings).toHaveLength(1)
+    expect(thresholdWarnings[0].severity).toBe('error')
+  })
+
+  it('warns when threshold is approaching (80%+)', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice({ subtotal_sek: 100000 })],
+      invoiceItems: [makeItem({ total_sek: 100000 })],
+      customers: [makeCustomer()],
+      products: [makeProduct()],
+      priorCumulativeValue: 10_000_000,
+    })
+
+    const approaching = report.warnings.filter(w => w.type === 'threshold_approaching')
+    expect(approaching).toHaveLength(1)
+    expect(approaching[0].severity).toBe('warning')
+  })
+
+  // ── Default values ────────────────────────────────────────
+
+  it('uses custom default transaction nature and delivery terms', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      invoiceItems: [makeItem()],
+      customers: [makeCustomer()],
+      products: [makeProduct()],
+      defaultTransactionNature: '31',
+      defaultDeliveryTerms: 'DAP',
+    })
+
+    expect(report.lines[0].transactionNature).toBe('31')
+    expect(report.lines[0].deliveryTerms).toBe('DAP')
+  })
+
+  it('defaults to transaction nature 11 and FCA', () => {
+    const report = generateIntrastatReport({
+      ...BASE_OPTIONS,
+      invoices: [makeInvoice()],
+      invoiceItems: [makeItem()],
+      customers: [makeCustomer()],
+      products: [makeProduct()],
+    })
+
+    expect(report.lines[0].transactionNature).toBe('11')
+    expect(report.lines[0].deliveryTerms).toBe('FCA')
+  })
+
+  // ── Period info ───────────────────────────────────────────
+
+  it('includes period and reporter info', () => {
+    const report = generateIntrastatReport(BASE_OPTIONS)
+
+    expect(report.period).toEqual({ year: 2026, month: 1 })
+    expect(report.reporterVatNumber).toBe('SE556677889901')
+    expect(report.reporterName).toBe('Test AB')
+  })
+})
+
+// ── Deadline tests ──────────────────────────────────────────
+
+describe('getIntrastatDeadline', () => {
+  it('returns 14th of following month', () => {
+    expect(getIntrastatDeadline(2026, 1)).toBe('2026-02-14')
+    expect(getIntrastatDeadline(2026, 6)).toBe('2026-07-14')
+  })
+
+  it('rolls over to next year for December', () => {
+    expect(getIntrastatDeadline(2026, 12)).toBe('2027-01-14')
+  })
+})

extensions/export/intrastat/lib/__tests__/scb-csv-generator.test.ts

@@ -0,0 +1,203 @@
+import { describe, it, expect } from 'vitest'
+import { generateSCBCsv, generateSCBFilename } from '../scb-csv-generator'
+import type { IntrastatReport, IntrastatLine } from '../intrastat-engine'
+
+// ── Fixtures ────────────────────────────────────────────────
+
+function makeLine(overrides: Partial<IntrastatLine> = {}): IntrastatLine {
+  return {
+    cnCode: '72163100',
+    partnerCountry: 'DE',
+    countryOfOrigin: 'SE',
+    transactionNature: '11',
+    deliveryTerms: 'FCA',
+    invoicedValue: 100000,
+    netMass: 4550,
+    supplementaryUnit: null,
+    supplementaryUnitType: null,
+    partnerVatId: 'DE123456789',
+    ...overrides,
+  }
+}
+
+function makeReport(overrides: Partial<IntrastatReport> = {}): IntrastatReport {
+  return {
+    period: { year: 2026, month: 1 },
+    reporterVatNumber: 'SE556677889901',
+    reporterName: 'Test AB',
+    flowType: 'dispatch',
+    lines: [makeLine()],
+    totals: { invoicedValue: 100000, netMass: 4550, lineCount: 1 },
+    thresholdStatus: {
+      cumulativeValue: 100000,
+      threshold: 12000000,
+      isObligated: false,
+      percentageUsed: 0.83,
+    },
+    warnings: [],
+    invoiceCount: 1,
+    ...overrides,
+  }
+}
+
+// ── CSV generation ──────────────────────────────────────────
+
+describe('generateSCBCsv', () => {
+  it('starts with UTF-8 BOM', () => {
+    const csv = generateSCBCsv(makeReport())
+    expect(csv.charCodeAt(0)).toBe(0xFEFF)
+  })
+
+  it('has correct header row', () => {
+    const csv = generateSCBCsv(makeReport())
+    const lines = csv.replace('\uFEFF', '').split('\r\n')
+    expect(lines[0]).toBe(
+      'CN-kod;Partnerland;Ursprungsland;Transaktionstyp;Leveransvillkor;Fakturerat värde (SEK);Nettovikt (kg);Kompletterande enhet;Partner-VAT'
+    )
+  })
+
+  it('uses semicolons as delimiter', () => {
+    const csv = generateSCBCsv(makeReport())
+    const lines = csv.replace('\uFEFF', '').split('\r\n')
+    // Header has 9 columns = 8 semicolons
+    expect(lines[0].split(';')).toHaveLength(9)
+    // Data row also has 9 columns
+    expect(lines[1].split(';')).toHaveLength(9)
+  })
+
+  it('uses CRLF line endings', () => {
+    const csv = generateSCBCsv(makeReport())
+    expect(csv).toContain('\r\n')
+    // Should not contain lone LF without preceding CR
+    const withoutCRLF = csv.replace(/\r\n/g, '')
+    expect(withoutCRLF).not.toContain('\n')
+  })
+
+  it('ends with CRLF', () => {
+    const csv = generateSCBCsv(makeReport())
+    expect(csv.endsWith('\r\n')).toBe(true)
+  })
+
+  it('renders data row with correct values', () => {
+    const csv = generateSCBCsv(makeReport())
+    const lines = csv.replace('\uFEFF', '').split('\r\n')
+    const cols = lines[1].split(';')
+    expect(cols[0]).toBe('72163100')    // CN-kod
+    expect(cols[1]).toBe('DE')           // Partnerland
+    expect(cols[2]).toBe('SE')           // Ursprungsland
+    expect(cols[3]).toBe('11')           // Transaktionstyp
+    expect(cols[4]).toBe('FCA')          // Leveransvillkor
+    expect(cols[5]).toBe('100000')       // Fakturerat värde
+    expect(cols[6]).toBe('4550')         // Nettovikt
+    expect(cols[7]).toBe('')             // Kompletterande enhet (null)
+    expect(cols[8]).toBe('DE123456789')  // Partner-VAT
+  })
+
+  it('rounds invoiced value to whole SEK', () => {
+    const csv = generateSCBCsv(makeReport({
+      lines: [makeLine({ invoicedValue: 123456.78 })],
+    }))
+    const lines = csv.replace('\uFEFF', '').split('\r\n')
+    const value = lines[1].split(';')[5]
+    expect(value).toBe('123457') // Rounded up
+  })
+
+  it('formats integer mass without decimals', () => {
+    const csv = generateSCBCsv(makeReport({
+      lines: [makeLine({ netMass: 4550 })],
+    }))
+    const lines = csv.replace('\uFEFF', '').split('\r\n')
+    const mass = lines[1].split(';')[6]
+    expect(mass).toBe('4550')
+  })
+
+  it('formats fractional mass with up to 3 decimal places', () => {
+    const csv = generateSCBCsv(makeReport({
+      lines: [makeLine({ netMass: 45.123 })],
+    }))
+    const lines = csv.replace('\uFEFF', '').split('\r\n')
+    const mass = lines[1].split(';')[6]
+    expect(mass).toBe('45.123')
+  })
+
+  it('removes trailing zeros from mass', () => {
+    const csv = generateSCBCsv(makeReport({
+      lines: [makeLine({ netMass: 45.1 })],
+    }))
+    const lines = csv.replace('\uFEFF', '').split('\r\n')
+    const mass = lines[1].split(';')[6]
+    expect(mass).toBe('45.1')
+  })
+
+  it('rounds mass to max 3 decimal places', () => {
+    const csv = generateSCBCsv(makeReport({
+      lines: [makeLine({ netMass: 45.12345 })],
+    }))
+    const lines = csv.replace('\uFEFF', '').split('\r\n')
+    const mass = lines[1].split(';')[6]
+    expect(mass).toBe('45.123')
+  })
+
+  it('includes supplementary unit when present', () => {
+    const csv = generateSCBCsv(makeReport({
+      lines: [makeLine({ supplementaryUnit: 150 })],
+    }))
+    const lines = csv.replace('\uFEFF', '').split('\r\n')
+    const suppUnit = lines[1].split(';')[7]
+    expect(suppUnit).toBe('150')
+  })
+
+  it('rounds supplementary unit to whole number', () => {
+    const csv = generateSCBCsv(makeReport({
+      lines: [makeLine({ supplementaryUnit: 150.7 })],
+    }))
+    const lines = csv.replace('\uFEFF', '').split('\r\n')
+    const suppUnit = lines[1].split(';')[7]
+    expect(suppUnit).toBe('151')
+  })
+
+  it('renders multiple data rows', () => {
+    const report = makeReport({
+      lines: [
+        makeLine({ cnCode: '72163100', partnerCountry: 'DE' }),
+        makeLine({ cnCode: '84818019', partnerCountry: 'FI', partnerVatId: 'FI12345678' }),
+      ],
+    })
+    const csv = generateSCBCsv(report)
+    const lines = csv.replace('\uFEFF', '').split('\r\n').filter(l => l.length > 0)
+    expect(lines).toHaveLength(3) // header + 2 data rows
+    expect(lines[1].split(';')[0]).toBe('72163100')
+    expect(lines[2].split(';')[0]).toBe('84818019')
+  })
+
+  it('generates empty CSV with only header when no lines', () => {
+    const csv = generateSCBCsv(makeReport({ lines: [] }))
+    const lines = csv.replace('\uFEFF', '').split('\r\n').filter(l => l.length > 0)
+    expect(lines).toHaveLength(1) // header only
+    expect(lines[0]).toContain('CN-kod')
+  })
+})
+
+// ── Filename generation ─────────────────────────────────────
+
+describe('generateSCBFilename', () => {
+  it('generates correct filename', () => {
+    const filename = generateSCBFilename(makeReport())
+    expect(filename).toBe('INTRASTAT_SE556677889901_2026-01.csv')
+  })
+
+  it('pads single-digit month', () => {
+    const filename = generateSCBFilename(makeReport({ period: { year: 2026, month: 3 } }))
+    expect(filename).toBe('INTRASTAT_SE556677889901_2026-03.csv')
+  })
+
+  it('does not pad double-digit month', () => {
+    const filename = generateSCBFilename(makeReport({ period: { year: 2026, month: 12 } }))
+    expect(filename).toBe('INTRASTAT_SE556677889901_2026-12.csv')
+  })
+
+  it('strips whitespace from VAT number', () => {
+    const filename = generateSCBFilename(makeReport({ reporterVatNumber: 'SE 5566 7788 9901' }))
+    expect(filename).toBe('INTRASTAT_SE556677889901_2026-01.csv')
+  })
+})

extensions/export/intrastat/lib/intrastat-engine.ts

@@ -0,0 +1,466 @@
+/**
+ * Intrastat Generator Engine
+ *
+ * Aggregates EU B2B goods sales into Intrastat declaration lines
+ * for reporting to SCB (Statistiska Centralbyrån) via IDEP.web.
+ *
+ * Pure functions — no Supabase, no React, no side effects.
+ *
+ * Only covers dispatches (utförsel) — goods sent from Sweden to
+ * other EU member states. Services are excluded from Intrastat.
+ *
+ * Threshold: SEK 12,000,000 cumulative dispatches over 12 months
+ * determines mandatory reporting obligation.
+ *
+ * Reference: SCB Intrastat guidelines, Combined Nomenclature (CN)
+ */
+
+import { isEUCountry, toCountryCode } from '@/extensions/export/shared/eu-countries'
+
+// ── Types ────────────────────────────────────────────────────
+
+/** Invoice data needed for Intrastat */
+export interface IntrastatInvoice {
+  id: string
+  invoice_number: string
+  invoice_date: string
+  status: string
+  vat_treatment: string
+  moms_ruta: string | null
+  currency: string
+  total_sek: number | null
+  subtotal_sek: number | null
+  subtotal: number
+  document_type: string
+  credited_invoice_id: string | null
+  customer_id: string
+}
+
+/** Customer data for Intrastat */
+export interface IntrastatCustomer {
+  id: string
+  name: string
+  country: string
+  vat_number: string | null
+}
+
+/** Product metadata stored in extension_data */
+export interface ProductMetadata {
+  productId: string
+  cnCode: string | null
+  description: string
+  netWeightKg: number | null
+  countryOfOrigin: string
+  supplementaryUnit: number | null
+  supplementaryUnitType: string | null
+}
+
+/** Invoice line item for matching to products */
+export interface IntrastatInvoiceItem {
+  id: string
+  invoice_id: string
+  description: string
+  quantity: number
+  unit_price: number
+  total: number
+  total_sek: number | null
+}
+
+/** Aggregated Intrastat declaration line */
+export interface IntrastatLine {
+  cnCode: string
+  partnerCountry: string
+  countryOfOrigin: string
+  transactionNature: string
+  deliveryTerms: string
+  invoicedValue: number
+  netMass: number
+  supplementaryUnit: number | null
+  supplementaryUnitType: string | null
+  partnerVatId: string
+}
+
+/** Warning about data quality */
+export interface IntrastatWarning {
+  type:
+    | 'missing_cn_code'
+    | 'missing_weight'
+    | 'missing_origin'
+    | 'threshold_approaching'
+    | 'threshold_exceeded'
+  severity: 'error' | 'warning'
+  invoiceId?: string
+  invoiceNumber?: string
+  productId?: string
+  message: string
+}
+
+/** Threshold monitoring status */
+export interface ThresholdStatus {
+  cumulativeValue: number
+  threshold: number
+  isObligated: boolean
+  percentageUsed: number
+}
+
+/** Complete Intrastat report */
+export interface IntrastatReport {
+  period: { year: number; month: number }
+  reporterVatNumber: string
+  reporterName: string
+  flowType: 'dispatch'
+  lines: IntrastatLine[]
+  totals: {
+    invoicedValue: number
+    netMass: number
+    lineCount: number
+  }
+  thresholdStatus: ThresholdStatus
+  warnings: IntrastatWarning[]
+  invoiceCount: number
+}
+
+/** Options for generating the Intrastat report */
+export interface IntrastatOptions {
+  invoices: IntrastatInvoice[]
+  invoiceItems: IntrastatInvoiceItem[]
+  customers: IntrastatCustomer[]
+  products: ProductMetadata[]
+  reporterVatNumber: string
+  reporterName: string
+  year: number
+  month: number
+  defaultTransactionNature?: string
+  defaultDeliveryTerms?: string
+  /** Cumulative dispatch value from prior months in the rolling 12-month window */
+  priorCumulativeValue?: number
+}
+
+// ── Constants ───────────────────────────────────────────────
+
+/** SCB Intrastat reporting threshold in SEK (12 million) */
+const INTRASTAT_THRESHOLD = 12_000_000
+
+/** Goods revenue accounts that trigger Intrastat reporting */
+const GOODS_ACCOUNTS_RUTA = ['35']
+
+// ── Core engine ──────────────────────────────────────────────
+
+export function generateIntrastatReport(options: IntrastatOptions): IntrastatReport {
+  const {
+    invoices,
+    invoiceItems,
+    customers,
+    products,
+    reporterVatNumber,
+    reporterName,
+    year,
+    month,
+    defaultTransactionNature = '11',
+    defaultDeliveryTerms = 'FCA',
+    priorCumulativeValue = 0,
+  } = options
+
+  const warnings: IntrastatWarning[] = []
+  const customerMap = new Map(customers.map(c => [c.id, c]))
+  const productMap = buildProductMap(products)
+
+  // Step 1: Filter to EU B2B goods invoices
+  const relevantInvoices = invoices.filter(inv => {
+    if (!['sent', 'paid', 'overdue'].includes(inv.status)) return false
+    if (inv.document_type !== 'invoice' && inv.credited_invoice_id === null) return false
+    if (inv.vat_treatment !== 'reverse_charge') return false
+    // Only goods (moms_ruta 35) — services are excluded from Intrastat
+    if (inv.moms_ruta && !GOODS_ACCOUNTS_RUTA.includes(inv.moms_ruta)) return false
+    // Verify customer is in EU (not Sweden)
+    const customer = customerMap.get(inv.customer_id)
+    if (!customer || !isEUCountry(customer.country)) return false
+    return true
+  })
+
+  // Step 2: Build items index by invoice_id
+  const itemsByInvoice = new Map<string, IntrastatInvoiceItem[]>()
+  for (const item of invoiceItems) {
+    const list = itemsByInvoice.get(item.invoice_id) ?? []
+    list.push(item)
+    itemsByInvoice.set(item.invoice_id, list)
+  }
+
+  // Step 3: Build aggregation map
+  // Key: cnCode|partnerCountry|countryOfOrigin|transactionNature|deliveryTerms
+  const aggregation = new Map<string, IntrastatLine>()
+
+  for (const invoice of relevantInvoices) {
+    const customer = customerMap.get(invoice.customer_id)!
+    const partnerCountryCode = toCountryCode(customer.country)
+    const isCreditNote = invoice.credited_invoice_id !== null
+    const items = itemsByInvoice.get(invoice.id) ?? []
+
+    if (items.length === 0) {
+      // No line items — use invoice-level amount with unknown product
+      const amountSek = getInvoiceAmountSek(invoice)
+      const effectiveAmount = isCreditNote ? -Math.abs(amountSek) : amountSek
+
+      warnings.push({
+        type: 'missing_cn_code',
+        severity: 'error',
+        invoiceId: invoice.id,
+        invoiceNumber: invoice.invoice_number,
+        message: `Faktura ${invoice.invoice_number} saknar fakturarader — kan inte tilldela CN-kod.`,
+      })
+
+      const key = buildAggKey('00000000', partnerCountryCode, 'SE', defaultTransactionNature, defaultDeliveryTerms)
+      addToAggregation(aggregation, key, {
+        cnCode: '00000000',
+        partnerCountry: partnerCountryCode,
+        countryOfOrigin: 'SE',
+        transactionNature: defaultTransactionNature,
+        deliveryTerms: defaultDeliveryTerms,
+        invoicedValue: effectiveAmount,
+        netMass: 0,
+        supplementaryUnit: null,
+        supplementaryUnitType: null,
+        partnerVatId: customer.vat_number ?? '',
+      })
+      continue
+    }
+
+    // Process each line item
+    for (const item of items) {
+      const product = matchProduct(item.description, productMap)
+      const amountSek = item.total_sek ?? item.total
+      const effectiveAmount = isCreditNote ? -Math.abs(amountSek) : amountSek
+
+      if (!product) {
+        // No product metadata found — use defaults and warn
+        warnings.push({
+          type: 'missing_cn_code',
+          severity: 'error',
+          invoiceId: invoice.id,
+          invoiceNumber: invoice.invoice_number,
+          message: `Faktura ${invoice.invoice_number}, rad "${item.description}" — ingen matchande produkt med CN-kod hittad.`,
+        })
+
+        const key = buildAggKey('00000000', partnerCountryCode, 'SE', defaultTransactionNature, defaultDeliveryTerms)
+        addToAggregation(aggregation, key, {
+          cnCode: '00000000',
+          partnerCountry: partnerCountryCode,
+          countryOfOrigin: 'SE',
+          transactionNature: defaultTransactionNature,
+          deliveryTerms: defaultDeliveryTerms,
+          invoicedValue: effectiveAmount,
+          netMass: 0,
+          supplementaryUnit: null,
+          supplementaryUnitType: null,
+          partnerVatId: customer.vat_number ?? '',
+        })
+        continue
+      }
+
+      // Validate product metadata
+      if (!product.cnCode) {
+        warnings.push({
+          type: 'missing_cn_code',
+          severity: 'error',
+          productId: product.productId,
+          invoiceId: invoice.id,
+          invoiceNumber: invoice.invoice_number,
+          message: `Produkt "${product.description}" saknar CN-kod.`,
+        })
+      }
+
+      if (product.netWeightKg === null) {
+        warnings.push({
+          type: 'missing_weight',
+          severity: 'warning',
+          productId: product.productId,
+          invoiceId: invoice.id,
+          invoiceNumber: invoice.invoice_number,
+          message: `Produkt "${product.description}" saknar nettovikt.`,
+        })
+      }
+
+      const cnCode = product.cnCode ?? '00000000'
+      const origin = product.countryOfOrigin || 'SE'
+      const mass = (product.netWeightKg ?? 0) * item.quantity
+      const suppUnit = product.supplementaryUnit !== null
+        ? product.supplementaryUnit * item.quantity
+        : null
+
+      const key = buildAggKey(cnCode, partnerCountryCode, origin, defaultTransactionNature, defaultDeliveryTerms)
+      addToAggregation(aggregation, key, {
+        cnCode,
+        partnerCountry: partnerCountryCode,
+        countryOfOrigin: origin,
+        transactionNature: defaultTransactionNature,
+        deliveryTerms: defaultDeliveryTerms,
+        invoicedValue: effectiveAmount,
+        netMass: isCreditNote ? -Math.abs(mass) : mass,
+        supplementaryUnit: suppUnit !== null ? (isCreditNote ? -Math.abs(suppUnit) : suppUnit) : null,
+        supplementaryUnitType: product.supplementaryUnitType,
+        partnerVatId: customer.vat_number ?? '',
+      })
+    }
+  }
+
+  // Step 4: Build sorted output
+  const lines = Array.from(aggregation.values())
+    .map(line => ({
+      ...line,
+      invoicedValue: round2(line.invoicedValue),
+      netMass: round3(line.netMass),
+    }))
+    .sort((a, b) =>
+      a.cnCode.localeCompare(b.cnCode) ||
+      a.partnerCountry.localeCompare(b.partnerCountry)
+    )
+
+  // Step 5: Calculate totals
+  const totals = {
+    invoicedValue: round2(lines.reduce((sum, l) => sum + l.invoicedValue, 0)),
+    netMass: round3(lines.reduce((sum, l) => sum + l.netMass, 0)),
+    lineCount: lines.length,
+  }
+
+  // Step 6: Threshold status
+  const cumulativeValue = round2(priorCumulativeValue + totals.invoicedValue)
+  const percentageUsed = INTRASTAT_THRESHOLD > 0
+    ? round2((cumulativeValue / INTRASTAT_THRESHOLD) * 100)
+    : 0
+
+  const thresholdStatus: ThresholdStatus = {
+    cumulativeValue,
+    threshold: INTRASTAT_THRESHOLD,
+    isObligated: cumulativeValue >= INTRASTAT_THRESHOLD,
+    percentageUsed,
+  }
+
+  if (percentageUsed >= 100) {
+    warnings.push({
+      type: 'threshold_exceeded',
+      severity: 'error',
+      message: `Tröskelvärdet för Intrastat (${formatSEK(INTRASTAT_THRESHOLD)} SEK) har överskridits. Rapportering till SCB är obligatorisk.`,
+    })
+  } else if (percentageUsed >= 80) {
+    warnings.push({
+      type: 'threshold_approaching',
+      severity: 'warning',
+      message: `Ackumulerad utförsel är ${formatSEK(cumulativeValue)} SEK (${percentageUsed}% av tröskelvärdet). Rapporteringsskyldighet kan uppstå snart.`,
+    })
+  }
+
+  return {
+    period: { year, month },
+    reporterVatNumber,
+    reporterName,
+    flowType: 'dispatch',
+    lines,
+    totals,
+    thresholdStatus,
+    warnings,
+    invoiceCount: relevantInvoices.length,
+  }
+}
+
+// ── Product matching ────────────────────────────────────────
+
+/**
+ * Build a map for fast product lookup by description (case-insensitive).
+ * Products are matched by exact description or by productId.
+ */
+function buildProductMap(products: ProductMetadata[]): Map<string, ProductMetadata> {
+  const map = new Map<string, ProductMetadata>()
+  for (const product of products) {
+    map.set(product.productId.toLowerCase(), product)
+    if (product.description) {
+      map.set(product.description.toLowerCase(), product)
+    }
+  }
+  return map
+}
+
+/**
+ * Match an invoice line description to a product.
+ * Tries exact match first, then checks if description starts with a product key.
+ */
+function matchProduct(description: string, productMap: Map<string, ProductMetadata>): ProductMetadata | null {
+  const lower = description.toLowerCase().trim()
+
+  // Exact match
+  if (productMap.has(lower)) return productMap.get(lower)!
+
+  // Prefix match (invoice description may contain extra details)
+  for (const [key, product] of productMap) {
+    if (lower.startsWith(key) || key.startsWith(lower)) {
+      return product
+    }
+  }
+
+  return null
+}
+
+// ── Aggregation helpers ─────────────────────────────────────
+
+function buildAggKey(
+  cnCode: string,
+  partnerCountry: string,
+  origin: string,
+  transactionNature: string,
+  deliveryTerms: string,
+): string {
+  return `${cnCode}|${partnerCountry}|${origin}|${transactionNature}|${deliveryTerms}`
+}
+
+function addToAggregation(
+  map: Map<string, IntrastatLine>,
+  key: string,
+  line: IntrastatLine,
+): void {
+  const existing = map.get(key)
+  if (existing) {
+    existing.invoicedValue += line.invoicedValue
+    existing.netMass += line.netMass
+    if (existing.supplementaryUnit !== null && line.supplementaryUnit !== null) {
+      existing.supplementaryUnit += line.supplementaryUnit
+    }
+    // Keep the first partner VAT ID encountered
+  } else {
+    map.set(key, { ...line })
+  }
+}
+
+// ── Amount helpers ──────────────────────────────────────────
+
+function getInvoiceAmountSek(invoice: IntrastatInvoice): number {
+  if (invoice.subtotal_sek !== null) return round2(invoice.subtotal_sek)
+  return round2(invoice.subtotal)
+}
+
+function round2(value: number): number {
+  return Math.round(value * 100) / 100
+}
+
+function round3(value: number): number {
+  return Math.round(value * 1000) / 1000
+}
+
+function formatSEK(amount: number): string {
+  return Math.round(amount).toLocaleString('sv-SE')
+}
+
+// ── Period helpers ───────────────────────────────────────────
+
+/**
+ * Get the Intrastat filing deadline for a month.
+ * The deadline is the 10th business day of the following month.
+ * For simplicity, we approximate as the 14th of the following month.
+ */
+export function getIntrastatDeadline(year: number, month: number): string {
+  let deadlineMonth = month + 1
+  let deadlineYear = year
+  if (deadlineMonth > 12) {
+    deadlineMonth = 1
+    deadlineYear++
+  }
+  return `${deadlineYear}-${String(deadlineMonth).padStart(2, '0')}-14`
+}

extensions/export/intrastat/lib/scb-csv-generator.ts

@@ -0,0 +1,74 @@
+/**
+ * Intrastat SCB CSV Generator
+ *
+ * Generates a semicolon-separated CSV file (UTF-8 with BOM)
+ * compatible with SCB's IDEP.web upload for Intrastat declarations.
+ *
+ * Format: Semicolon-delimited, UTF-8 BOM, whole SEK amounts,
+ * net mass in kg with up to 3 decimal places.
+ *
+ * Reference: SCB IDEP.web filformat, Intrastat utförsel
+ */
+
+import type { IntrastatReport } from './intrastat-engine'
+
+const UTF8_BOM = '\uFEFF'
+
+/**
+ * Generate an IDEP.web-compatible CSV for the Intrastat report.
+ *
+ * Columns (matching SCB IDEP.web format):
+ *   CN-kod;Partnerland;Ursprungsland;Transaktionstyp;Leveransvillkor;
+ *   Fakturerat värde (SEK);Nettovikt (kg);Kompletterande enhet;Partner-VAT
+ */
+export function generateSCBCsv(report: IntrastatReport): string {
+  const header = [
+    'CN-kod',
+    'Partnerland',
+    'Ursprungsland',
+    'Transaktionstyp',
+    'Leveransvillkor',
+    'Fakturerat värde (SEK)',
+    'Nettovikt (kg)',
+    'Kompletterande enhet',
+    'Partner-VAT',
+  ].join(';')
+
+  const rows = report.lines.map(line => {
+    const value = Math.round(line.invoicedValue)
+    const mass = roundMass(line.netMass)
+    const suppUnit = line.supplementaryUnit !== null ? String(Math.round(line.supplementaryUnit)) : ''
+
+    return [
+      line.cnCode,
+      line.partnerCountry,
+      line.countryOfOrigin,
+      line.transactionNature,
+      line.deliveryTerms,
+      String(value),
+      String(mass),
+      suppUnit,
+      line.partnerVatId,
+    ].join(';')
+  })
+
+  return UTF8_BOM + [header, ...rows].join('\r\n') + '\r\n'
+}
+
+/**
+ * Generate a filename for the IDEP.web CSV download.
+ *
+ * Format: INTRASTAT_<VAT>_<YYYY>-<MM>.csv
+ */
+export function generateSCBFilename(report: IntrastatReport): string {
+  const vat = report.reporterVatNumber.replace(/\s/g, '')
+  const period = `${report.period.year}-${String(report.period.month).padStart(2, '0')}`
+  return `INTRASTAT_${vat}_${period}.csv`
+}
+
+/** Round mass to max 3 decimal places, removing trailing zeros */
+function roundMass(kg: number): string {
+  const rounded = Math.round(kg * 1000) / 1000
+  if (rounded === Math.floor(rounded)) return String(rounded)
+  return rounded.toFixed(3).replace(/0+$/, '')
+}

extensions/export/shared/eu-countries.ts

@@ -0,0 +1,113 @@
+/**
+ * EU member states reference data.
+ *
+ * Used by export extensions for:
+ * - Filtering EU vs non-EU customers
+ * - VIES VAT number validation (country prefix)
+ * - Intrastat partner country lookup
+ * - EC Sales List country grouping
+ */
+
+export interface EUCountry {
+  code: string       // ISO 3166-1 alpha-2
+  name: string       // Swedish name
+  nameEn: string     // English name
+  vatPrefix: string  // VIES VAT number prefix
+  currency: string   // Primary currency
+}
+
+/**
+ * All 27 EU member states (as of 2025).
+ * Sweden (SE) is included but should be filtered out for intra-community checks.
+ */
+export const EU_COUNTRIES: EUCountry[] = [
+  { code: 'AT', name: 'Österrike', nameEn: 'Austria', vatPrefix: 'AT', currency: 'EUR' },
+  { code: 'BE', name: 'Belgien', nameEn: 'Belgium', vatPrefix: 'BE', currency: 'EUR' },
+  { code: 'BG', name: 'Bulgarien', nameEn: 'Bulgaria', vatPrefix: 'BG', currency: 'BGN' },
+  { code: 'HR', name: 'Kroatien', nameEn: 'Croatia', vatPrefix: 'HR', currency: 'EUR' },
+  { code: 'CY', name: 'Cypern', nameEn: 'Cyprus', vatPrefix: 'CY', currency: 'EUR' },
+  { code: 'CZ', name: 'Tjeckien', nameEn: 'Czech Republic', vatPrefix: 'CZ', currency: 'CZK' },
+  { code: 'DK', name: 'Danmark', nameEn: 'Denmark', vatPrefix: 'DK', currency: 'DKK' },
+  { code: 'EE', name: 'Estland', nameEn: 'Estonia', vatPrefix: 'EE', currency: 'EUR' },
+  { code: 'FI', name: 'Finland', nameEn: 'Finland', vatPrefix: 'FI', currency: 'EUR' },
+  { code: 'FR', name: 'Frankrike', nameEn: 'France', vatPrefix: 'FR', currency: 'EUR' },
+  { code: 'DE', name: 'Tyskland', nameEn: 'Germany', vatPrefix: 'DE', currency: 'EUR' },
+  { code: 'GR', name: 'Grekland', nameEn: 'Greece', vatPrefix: 'EL', currency: 'EUR' },
+  { code: 'HU', name: 'Ungern', nameEn: 'Hungary', vatPrefix: 'HU', currency: 'HUF' },
+  { code: 'IE', name: 'Irland', nameEn: 'Ireland', vatPrefix: 'IE', currency: 'EUR' },
+  { code: 'IT', name: 'Italien', nameEn: 'Italy', vatPrefix: 'IT', currency: 'EUR' },
+  { code: 'LV', name: 'Lettland', nameEn: 'Latvia', vatPrefix: 'LV', currency: 'EUR' },
+  { code: 'LT', name: 'Litauen', nameEn: 'Lithuania', vatPrefix: 'LT', currency: 'EUR' },
+  { code: 'LU', name: 'Luxemburg', nameEn: 'Luxembourg', vatPrefix: 'LU', currency: 'EUR' },
+  { code: 'MT', name: 'Malta', nameEn: 'Malta', vatPrefix: 'MT', currency: 'EUR' },
+  { code: 'NL', name: 'Nederländerna', nameEn: 'Netherlands', vatPrefix: 'NL', currency: 'EUR' },
+  { code: 'PL', name: 'Polen', nameEn: 'Poland', vatPrefix: 'PL', currency: 'PLN' },
+  { code: 'PT', name: 'Portugal', nameEn: 'Portugal', vatPrefix: 'PT', currency: 'EUR' },
+  { code: 'RO', name: 'Rumänien', nameEn: 'Romania', vatPrefix: 'RO', currency: 'RON' },
+  { code: 'SK', name: 'Slovakien', nameEn: 'Slovakia', vatPrefix: 'SK', currency: 'EUR' },
+  { code: 'SI', name: 'Slovenien', nameEn: 'Slovenia', vatPrefix: 'SI', currency: 'EUR' },
+  { code: 'ES', name: 'Spanien', nameEn: 'Spain', vatPrefix: 'ES', currency: 'EUR' },
+  { code: 'SE', name: 'Sverige', nameEn: 'Sweden', vatPrefix: 'SE', currency: 'SEK' },
+]
+
+/** EU country codes excluding Sweden (for intra-community checks) */
+export const EU_COUNTRY_CODES_EXCL_SE = EU_COUNTRIES
+  .filter(c => c.code !== 'SE')
+  .map(c => c.code)
+
+/** All EU country codes including Sweden */
+export const EU_COUNTRY_CODES = EU_COUNTRIES.map(c => c.code)
+
+/**
+ * Build a lookup set of all known names/codes for EU countries (excluding Sweden).
+ * Handles ISO codes, English names, and Swedish names — all uppercased for matching.
+ */
+const EU_LOOKUP_EXCL_SE = new Set(
+  EU_COUNTRIES
+    .filter(c => c.code !== 'SE')
+    .flatMap(c => [c.code, c.name, c.nameEn].map(s => s.toUpperCase()))
+)
+
+const EU_LOOKUP_INCL_SE = new Set(
+  EU_COUNTRIES
+    .flatMap(c => [c.code, c.name, c.nameEn].map(s => s.toUpperCase()))
+)
+
+/**
+ * Check if a country value is an EU member state (excluding Sweden).
+ * Accepts ISO codes ("DE"), English names ("Germany"), or Swedish names ("Tyskland").
+ */
+export function isEUCountry(country: string): boolean {
+  return EU_LOOKUP_EXCL_SE.has(country.trim().toUpperCase())
+}
+
+/**
+ * Check if a country value is an EU member state (including Sweden).
+ * Accepts ISO codes, English names, or Swedish names.
+ */
+export function isEUCountryIncludingSE(country: string): boolean {
+  return EU_LOOKUP_INCL_SE.has(country.trim().toUpperCase())
+}
+
+/** Get EU country data by ISO code, English name, or Swedish name */
+export function getEUCountry(country: string): EUCountry | undefined {
+  const upper = country.trim().toUpperCase()
+  return EU_COUNTRIES.find(
+    c => c.code === upper || c.name.toUpperCase() === upper || c.nameEn.toUpperCase() === upper
+  )
+}
+
+/** Get the VIES VAT prefix for a country (note: Greece uses 'EL' not 'GR') */
+export function getVatPrefix(countryCode: string): string | undefined {
+  return getEUCountry(countryCode)?.vatPrefix
+}
+
+/**
+ * Normalize a country value to its ISO 3166-1 alpha-2 code.
+ * Accepts ISO codes, English names, or Swedish names.
+ * Returns the input uppercased if no match is found.
+ */
+export function toCountryCode(country: string): string {
+  const found = getEUCountry(country)
+  return found ? found.code : country.trim().toUpperCase()
+}

extensions/export/shared/moms-box-mapping.ts

@@ -0,0 +1,132 @@
+/**
+ * Momsdeklaration box mapping for Swedish VAT returns.
+ *
+ * Maps BAS revenue accounts to the correct box (ruta) in the
+ * momsdeklaration filed with Skatteverket. Used by:
+ * - Export VAT Monitor (full box overview)
+ * - EU Sales List (cross-validation against box 35/39)
+ *
+ * Reference: Skatteverket momsdeklaration (SKV 4700)
+ * https://www.skatteverket.se/foretag/moms/deklareramoms/fyllaimomsdeklarationen
+ */
+
+/** Momsdeklaration box number */
+export type MomsBox =
+  | '05'  // Momspliktig forsaljning (taxable sales)
+  | '06'  // Momspliktiga uttag (taxable withdrawals)
+  | '07'  // Vinstmarginalbeskattning (margin scheme)
+  | '08'  // Hyresinkomster frivillig beskattning (rental)
+  | '10'  // Utgaende moms 25%
+  | '11'  // Utgaende moms 12%
+  | '12'  // Utgaende moms 6%
+  | '20'  // Inkop varor fran EU
+  | '21'  // Inkop tjanster fran EU
+  | '22'  // Inkop tjanster utanfor EU
+  | '23'  // Inkop varor Sverige omvand skattskyldighet
+  | '24'  // Inkop tjanster Sverige omvand skattskyldighet
+  | '30'  // Utgaende moms inkop 25%
+  | '31'  // Utgaende moms inkop 12%
+  | '32'  // Utgaende moms inkop 6%
+  | '35'  // Varuforssaljning till annat EU-land
+  | '36'  // Varuforssaljning utanfor EU (export)
+  | '37'  // Mellanmans inkop trepartshandel
+  | '38'  // Mellanmans forsaljning trepartshandel
+  | '39'  // Tjansteforssaljning EU (huvudregeln)
+  | '40'  // Ovrig forsaljning av tjanster utomlands
+  | '41'  // Forsaljning omvand skattskyldighet Sverige
+  | '42'  // Ovrig forsaljning m.m.
+  | '48'  // Ingaende moms att dra av
+  | '49'  // Moms att betala eller fa tillbaka
+  | '50'  // Importbeskattningsunderlag
+  | '60'  // Importmoms 25%
+  | '61'  // Importmoms 12%
+  | '62'  // Importmoms 6%
+
+/** Map BAS revenue account to momsdeklaration box */
+export const ACCOUNT_TO_BOX: Record<string, MomsBox> = {
+  // Domestic revenue (taxable) → Box 05
+  '3001': '05',  // Forsaljning varor/tjanster 25%
+  '3002': '05',  // Forsaljning varor/tjanster 12%
+  '3003': '05',  // Forsaljning varor/tjanster 6%
+
+  // EU goods (reverse charge, VAT-free) → Box 35
+  '3108': '35',  // Forsaljning varor till annat EU-land
+  '3521': '35',  // Fakturerade frakter EU (follows goods treatment)
+
+  // Non-EU goods export (zero-rated) → Box 36
+  '3105': '36',  // Forsaljning varor export utanfor EU
+  '3522': '36',  // Fakturerade frakter export
+
+  // Triangular trade → Box 38
+  '3109': '38',  // Mellanmans forsaljning trepartshandel
+
+  // EU services (reverse charge, main rule) → Box 39
+  '3308': '39',  // Forsaljning tjanster EU
+
+  // Non-EU services → Box 40
+  '3305': '40',  // Forsaljning tjanster export utanfor EU
+
+  // Output VAT → Boxes 10, 11, 12
+  '2611': '10',  // Utgaende moms 25%
+  '2621': '11',  // Utgaende moms 12%
+  '2631': '12',  // Utgaende moms 6%
+
+  // Input VAT → Box 48
+  '2641': '48',  // Ingaende moms
+  '2645': '48',  // Beraknad ingaende moms (EU forvarv)
+}
+
+/** Swedish labels for each momsdeklaration box */
+export const BOX_LABELS: Record<MomsBox, string> = {
+  '05': 'Momspliktig försäljning',
+  '06': 'Momspliktiga uttag',
+  '07': 'Vinstmarginalbeskattning',
+  '08': 'Hyresinkomster (frivillig beskattning)',
+  '10': 'Utgående moms 25%',
+  '11': 'Utgående moms 12%',
+  '12': 'Utgående moms 6%',
+  '20': 'Inköp varor från EU',
+  '21': 'Inköp tjänster från EU',
+  '22': 'Inköp tjänster utanför EU',
+  '23': 'Inköp varor Sverige (omvänd skattskyldighet)',
+  '24': 'Inköp tjänster Sverige (omvänd skattskyldighet)',
+  '30': 'Utgående moms på inköp 25%',
+  '31': 'Utgående moms på inköp 12%',
+  '32': 'Utgående moms på inköp 6%',
+  '35': 'Varuförsäljning till annat EU-land',
+  '36': 'Varuförsäljning utanför EU (export)',
+  '37': 'Mellanmans inköp vid trepartshandel',
+  '38': 'Mellanmans försäljning vid trepartshandel',
+  '39': 'Tjänsteförsäljning till EU (huvudregeln)',
+  '40': 'Övrig försäljning av tjänster utomlands',
+  '41': 'Försäljning med omvänd skattskyldighet (Sverige)',
+  '42': 'Övrig försäljning m.m.',
+  '48': 'Ingående moms att dra av',
+  '49': 'Moms att betala eller få tillbaka',
+  '50': 'Beskattningsunderlag vid import',
+  '60': 'Importmoms 25%',
+  '61': 'Importmoms 12%',
+  '62': 'Importmoms 6%',
+}
+
+/** Get the momsdeklaration box for a BAS account number */
+export function getBoxForAccount(accountNumber: string): MomsBox | undefined {
+  return ACCOUNT_TO_BOX[accountNumber]
+}
+
+/** Get the Swedish label for a momsdeklaration box */
+export function getBoxLabel(box: MomsBox): string {
+  return BOX_LABELS[box]
+}
+
+/** Boxes that represent VAT-exempt export/EU sales (no output VAT) */
+export const EXPORT_BOXES: MomsBox[] = ['35', '36', '38', '39', '40']
+
+/** Boxes that represent taxable domestic sales (have output VAT) */
+export const DOMESTIC_BOXES: MomsBox[] = ['05', '06', '07', '08']
+
+/** Boxes that represent output VAT */
+export const OUTPUT_VAT_BOXES: MomsBox[] = ['10', '11', '12']
+
+/** Boxes that represent input VAT */
+export const INPUT_VAT_BOXES: MomsBox[] = ['48']

extensions/export/vat-monitor/index.ts

@@ -0,0 +1,17 @@
+import type { Extension } from '@/lib/extensions/types'
+
+/**
+ * Export VAT Monitor / Exportmoms-monitor Extension
+ *
+ * Dashboard that maps GL revenue accounts to Swedish momsdeklaration boxes
+ * (05, 35, 36, 39, 40). Shows revenue breakdown by destination type:
+ * domestic, EU B2B (reverse charge), and non-EU export.
+ *
+ * Validates VAT treatment consistency and flags potential errors before
+ * the user files their momsdeklaration.
+ */
+export const vatMonitorExtension: Extension = {
+  id: 'vat-monitor',
+  name: 'Exportmoms-monitor',
+  version: '1.0.0',
+}

extensions/export/vat-monitor/lib/__tests__/vat-monitor-engine.test.ts

@@ -0,0 +1,477 @@
+import { describe, it, expect } from 'vitest'
+import {
+  generateVatMonitorReport,
+  type GLLine,
+  type VatMonitorInvoice,
+  type VatMonitorCustomer,
+  type VatMonitorOptions,
+} from '../vat-monitor-engine'
+
+// ── Helpers ─────────────────────────────────────────────────
+
+/** Create a credit GL line (revenue is credit-side) */
+function creditLine(account: string, amount: number): GLLine {
+  return { account_number: account, debit_amount: 0, credit_amount: amount }
+}
+
+/** Create a debit GL line (input VAT is debit-side) */
+function debitLine(account: string, amount: number): GLLine {
+  return { account_number: account, debit_amount: amount, credit_amount: 0 }
+}
+
+function makeInvoice(overrides: Partial<VatMonitorInvoice> = {}): VatMonitorInvoice {
+  return {
+    id: 'inv-1',
+    invoice_number: 'F2026-001',
+    vat_treatment: 'reverse_charge',
+    moms_ruta: '35',
+    customer_id: 'cust-1',
+    ...overrides,
+  }
+}
+
+function makeCustomer(overrides: Partial<VatMonitorCustomer> = {}): VatMonitorCustomer {
+  return {
+    id: 'cust-1',
+    name: 'Acme GmbH',
+    country: 'DE',
+    vat_number: 'DE123456789',
+    vat_number_validated: true,
+    ...overrides,
+  }
+}
+
+const BASE_OPTIONS: VatMonitorOptions = {
+  glLines: [],
+  year: 2026,
+  month: 1,
+}
+
+// ── Box mapping tests ───────────────────────────────────────
+
+describe('box mapping', () => {
+  it('maps domestic revenue (3001) to box 05', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3001', 100000)],
+    })
+
+    const box05 = report.boxes.find(b => b.boxNumber === '05')
+    expect(box05).toBeDefined()
+    expect(box05!.amount).toBe(100000)
+  })
+
+  it('maps EU goods (3108) to box 35', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3108', 50000)],
+    })
+
+    const box35 = report.boxes.find(b => b.boxNumber === '35')
+    expect(box35).toBeDefined()
+    expect(box35!.amount).toBe(50000)
+  })
+
+  it('maps EU freight (3521) to box 35 alongside 3108', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3108', 40000), creditLine('3521', 10000)],
+    })
+
+    const box35 = report.boxes.find(b => b.boxNumber === '35')
+    expect(box35!.amount).toBe(50000)
+    expect(box35!.accounts).toContain('3108')
+    expect(box35!.accounts).toContain('3521')
+  })
+
+  it('maps export goods (3105) to box 36', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3105', 80000)],
+    })
+
+    const box36 = report.boxes.find(b => b.boxNumber === '36')
+    expect(box36!.amount).toBe(80000)
+  })
+
+  it('maps export freight (3522) to box 36', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3522', 15000)],
+    })
+
+    const box36 = report.boxes.find(b => b.boxNumber === '36')
+    expect(box36!.amount).toBe(15000)
+  })
+
+  it('maps triangulation (3109) to box 38', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3109', 25000)],
+    })
+
+    const box38 = report.boxes.find(b => b.boxNumber === '38')
+    expect(box38!.amount).toBe(25000)
+  })
+
+  it('maps EU services (3308) to box 39', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3308', 30000)],
+    })
+
+    const box39 = report.boxes.find(b => b.boxNumber === '39')
+    expect(box39!.amount).toBe(30000)
+  })
+
+  it('maps export services (3305) to box 40', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3305', 20000)],
+    })
+
+    const box40 = report.boxes.find(b => b.boxNumber === '40')
+    expect(box40!.amount).toBe(20000)
+  })
+
+  it('maps output VAT (2611) to box 10', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('2611', 25000)],
+    })
+
+    const box10 = report.boxes.find(b => b.boxNumber === '10')
+    expect(box10!.amount).toBe(25000)
+  })
+
+  it('maps input VAT (2641) to box 48', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [debitLine('2641', 15000)],
+    })
+
+    const box48 = report.boxes.find(b => b.boxNumber === '48')
+    expect(box48!.amount).toBe(15000)
+  })
+})
+
+// ── Revenue breakdown tests ─────────────────────────────────
+
+describe('revenue breakdown', () => {
+  it('calculates correct breakdown for mixed revenue', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [
+        creditLine('3001', 200000),  // domestic
+        creditLine('3108', 100000),  // EU goods
+        creditLine('3308', 50000),   // EU services
+        creditLine('3105', 75000),   // export goods
+        creditLine('3305', 25000),   // export services
+      ],
+    })
+
+    const rb = report.revenueBreakdown
+    expect(rb.totalRevenue).toBe(450000)
+    expect(rb.domestic.amount).toBe(200000)
+    expect(rb.euGoods.amount).toBe(100000)
+    expect(rb.euServices.amount).toBe(50000)
+    expect(rb.exportGoods.amount).toBe(75000)
+    expect(rb.exportServices.amount).toBe(25000)
+  })
+
+  it('calculates correct percentages', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [
+        creditLine('3001', 50000),
+        creditLine('3108', 50000),
+      ],
+    })
+
+    expect(report.revenueBreakdown.domestic.percentage).toBe(50)
+    expect(report.revenueBreakdown.euGoods.percentage).toBe(50)
+  })
+
+  it('returns 0% when no revenue', () => {
+    const report = generateVatMonitorReport(BASE_OPTIONS)
+
+    expect(report.revenueBreakdown.totalRevenue).toBe(0)
+    expect(report.revenueBreakdown.domestic.percentage).toBe(0)
+  })
+
+  it('only domestic sales — export categories are zero', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3001', 100000)],
+    })
+
+    expect(report.revenueBreakdown.domestic.amount).toBe(100000)
+    expect(report.revenueBreakdown.euGoods.amount).toBe(0)
+    expect(report.revenueBreakdown.exportGoods.amount).toBe(0)
+  })
+})
+
+// ── VAT summary tests ───────────────────────────────────────
+
+describe('VAT summary', () => {
+  it('calculates net VAT: output - input = box 49', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [
+        creditLine('2611', 50000),  // output 25%
+        creditLine('2621', 12000),  // output 12%
+        creditLine('2631', 3000),   // output 6%
+        debitLine('2641', 30000),   // input VAT
+      ],
+    })
+
+    expect(report.vatSummary.outputVat25).toBe(50000)
+    expect(report.vatSummary.outputVat12).toBe(12000)
+    expect(report.vatSummary.outputVat6).toBe(3000)
+    expect(report.vatSummary.totalOutputVat).toBe(65000)
+    expect(report.vatSummary.inputVat).toBe(30000)
+    expect(report.vatSummary.netVat).toBe(35000)
+    expect(report.vatSummary.isRefund).toBe(false)
+  })
+
+  it('identifies refund when input > output', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [
+        creditLine('2611', 10000),
+        debitLine('2641', 50000),
+      ],
+    })
+
+    expect(report.vatSummary.netVat).toBe(-40000)
+    expect(report.vatSummary.isRefund).toBe(true)
+  })
+
+  it('box 49 appears in boxes list', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [
+        creditLine('2611', 25000),
+        debitLine('2641', 10000),
+      ],
+    })
+
+    const box49 = report.boxes.find(b => b.boxNumber === '49')
+    expect(box49).toBeDefined()
+    expect(box49!.amount).toBe(15000)
+    expect(box49!.label).toContain('betala')
+  })
+})
+
+// ── Invoice validation tests ────────────────────────────────
+
+describe('invoice validation', () => {
+  it('warns when reverse_charge invoice has customer without VAT number', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3108', 10000)],
+      invoices: [makeInvoice({ vat_treatment: 'reverse_charge' })],
+      customers: [makeCustomer({ vat_number: null })],
+    })
+
+    const missingVat = report.warnings.filter(w => w.type === 'missing_vat_number')
+    expect(missingVat).toHaveLength(1)
+    expect(missingVat[0].severity).toBe('error')
+  })
+
+  it('warns when reverse_charge invoice has unvalidated VAT number', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3108', 10000)],
+      invoices: [makeInvoice({ vat_treatment: 'reverse_charge' })],
+      customers: [makeCustomer({ vat_number_validated: false })],
+    })
+
+    const unvalidated = report.warnings.filter(w => w.type === 'unvalidated_vat_number')
+    expect(unvalidated).toHaveLength(1)
+    expect(unvalidated[0].severity).toBe('warning')
+  })
+
+  it('warns when moms_ruta does not match vat_treatment', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [],
+      invoices: [makeInvoice({ vat_treatment: 'standard_25', moms_ruta: '35' })],
+      customers: [makeCustomer()],
+    })
+
+    const mismatch = report.warnings.filter(w => w.type === 'vat_treatment_mismatch')
+    expect(mismatch).toHaveLength(1)
+  })
+
+  it('no warning when moms_ruta matches reverse_charge (35, 38, or 39)', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [],
+      invoices: [
+        makeInvoice({ id: 'i1', vat_treatment: 'reverse_charge', moms_ruta: '35' }),
+        makeInvoice({ id: 'i2', vat_treatment: 'reverse_charge', moms_ruta: '39' }),
+        makeInvoice({ id: 'i3', vat_treatment: 'reverse_charge', moms_ruta: '38' }),
+      ],
+      customers: [makeCustomer()],
+    })
+
+    const mismatch = report.warnings.filter(w => w.type === 'vat_treatment_mismatch')
+    expect(mismatch).toHaveLength(0)
+  })
+
+  it('no warning when moms_ruta matches export (36 or 40)', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [],
+      invoices: [
+        makeInvoice({ id: 'i1', vat_treatment: 'export', moms_ruta: '36' }),
+        makeInvoice({ id: 'i2', vat_treatment: 'export', moms_ruta: '40' }),
+      ],
+      customers: [makeCustomer()],
+    })
+
+    const mismatch = report.warnings.filter(w => w.type === 'vat_treatment_mismatch')
+    expect(mismatch).toHaveLength(0)
+  })
+
+  it('no validation warnings when no invoices provided', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3108', 10000)],
+    })
+
+    expect(report.warnings).toHaveLength(0)
+  })
+})
+
+// ── Period comparison tests ─────────────────────────────────
+
+describe('period comparison', () => {
+  it('calculates delta between current and previous period', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3001', 200000)],
+      previousGlLines: [creditLine('3001', 150000)],
+    })
+
+    expect(report.comparison).not.toBeNull()
+    expect(report.comparison!.domestic.current).toBe(200000)
+    expect(report.comparison!.domestic.previous).toBe(150000)
+    expect(report.comparison!.domestic.change).toBe(50000)
+    expect(report.comparison!.domestic.changePercent).toBeCloseTo(33.33, 1)
+  })
+
+  it('returns null changePercent when previous is zero', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3108', 50000)],
+      previousGlLines: [],
+    })
+
+    expect(report.comparison!.euGoods.changePercent).toBeNull()
+  })
+
+  it('shows negative delta when revenue decreased', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3001', 80000)],
+      previousGlLines: [creditLine('3001', 100000)],
+    })
+
+    expect(report.comparison!.domestic.change).toBe(-20000)
+    expect(report.comparison!.domestic.changePercent).toBe(-20)
+  })
+
+  it('no comparison when previousGlLines not provided', () => {
+    const report = generateVatMonitorReport(BASE_OPTIONS)
+    expect(report.comparison).toBeNull()
+  })
+
+  it('includes netVat comparison', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('2611', 50000), debitLine('2641', 20000)],
+      previousGlLines: [creditLine('2611', 40000), debitLine('2641', 25000)],
+    })
+
+    expect(report.comparison!.netVat.current).toBe(30000)
+    expect(report.comparison!.netVat.previous).toBe(15000)
+    expect(report.comparison!.netVat.change).toBe(15000)
+  })
+})
+
+// ── Empty / edge case tests ─────────────────────────────────
+
+describe('edge cases', () => {
+  it('generates empty report with no GL data', () => {
+    const report = generateVatMonitorReport(BASE_OPTIONS)
+
+    expect(report.boxes).toHaveLength(1) // Only box 49 (net = 0)
+    expect(report.revenueBreakdown.totalRevenue).toBe(0)
+    expect(report.vatSummary.netVat).toBe(0)
+    expect(report.warnings).toHaveLength(0)
+  })
+
+  it('ignores irrelevant accounts', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [
+        creditLine('1510', 100000),  // accounts receivable — not relevant
+        creditLine('3001', 50000),   // domestic revenue — relevant
+      ],
+    })
+
+    expect(report.revenueBreakdown.totalRevenue).toBe(50000)
+  })
+
+  it('handles mixed debit/credit on same account', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [
+        creditLine('3001', 100000),
+        { account_number: '3001', debit_amount: 10000, credit_amount: 0 }, // credit note reversal
+      ],
+    })
+
+    expect(report.revenueBreakdown.domestic.amount).toBe(90000)
+  })
+
+  it('rounds amounts to 2 decimal places', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [creditLine('3001', 33333.335)],
+    })
+
+    expect(report.revenueBreakdown.domestic.amount).toBe(33333.34)
+  })
+
+  it('boxes are sorted by box number', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      glLines: [
+        creditLine('2641', 0), // We need debit line for 2641
+        debitLine('2641', 10000),
+        creditLine('2611', 25000),
+        creditLine('3001', 100000),
+        creditLine('3108', 50000),
+      ],
+    })
+
+    const boxNumbers = report.boxes.map(b => b.boxNumber)
+    const sorted = [...boxNumbers].sort()
+    expect(boxNumbers).toEqual(sorted)
+  })
+
+  it('includes period info in report', () => {
+    const report = generateVatMonitorReport({
+      ...BASE_OPTIONS,
+      year: 2026,
+      month: 3,
+      quarter: undefined,
+    })
+
+    expect(report.period.year).toBe(2026)
+    expect(report.period.month).toBe(3)
+  })
+})

extensions/export/vat-monitor/lib/vat-monitor-engine.ts

@@ -0,0 +1,453 @@
+/**
+ * Export VAT Monitor Engine
+ *
+ * Analyses journal entry data to produce a momsdeklaration preview
+ * focused on export and intra-community trade. Maps BAS accounts to
+ * momsdeklaration boxes, breaks down revenue by destination type,
+ * and validates invoice-to-account consistency.
+ *
+ * Pure functions — no Supabase, no React, no side effects.
+ *
+ * Complements the core VatDeclaration report by adding:
+ *   - Revenue breakdown by destination (domestic / EU / non-EU)
+ *   - Invoice-level validation (vat_treatment vs account)
+ *   - Period-over-period comparison
+ *
+ * Reference: Skatteverket momsdeklaration (SKV 4700)
+ */
+
+import {
+  ACCOUNT_TO_BOX,
+  BOX_LABELS,
+  type MomsBox,
+} from '@/extensions/export/shared/moms-box-mapping'
+
+// ── Types ────────────────────────────────────────────────────
+
+/** Journal entry line data pre-fetched from GL */
+export interface GLLine {
+  account_number: string
+  debit_amount: number
+  credit_amount: number
+}
+
+/** Invoice data for validation (subset of core Invoice type) */
+export interface VatMonitorInvoice {
+  id: string
+  invoice_number: string
+  vat_treatment: string
+  moms_ruta: string | null
+  customer_id: string
+}
+
+/** Customer data for validation */
+export interface VatMonitorCustomer {
+  id: string
+  name: string
+  country: string
+  vat_number: string | null
+  vat_number_validated: boolean
+}
+
+/** A single momsdeklaration box result */
+export interface VatBoxData {
+  boxNumber: MomsBox
+  label: string
+  amount: number
+  accounts: string[]
+}
+
+/** Revenue breakdown by destination type */
+export interface RevenueBreakdown {
+  domestic: { amount: number; percentage: number }
+  euGoods: { amount: number; percentage: number }
+  euServices: { amount: number; percentage: number }
+  exportGoods: { amount: number; percentage: number }
+  exportServices: { amount: number; percentage: number }
+  triangular: { amount: number; percentage: number }
+  totalRevenue: number
+}
+
+/** Warning about VAT data quality */
+export interface VatMonitorWarning {
+  type:
+    | 'vat_treatment_mismatch'
+    | 'missing_vat_number'
+    | 'unvalidated_vat_number'
+    | 'wrong_account'
+  severity: 'error' | 'warning'
+  invoiceId?: string
+  invoiceNumber?: string
+  customerName?: string
+  message: string
+}
+
+/** Period comparison delta for a destination type */
+export interface PeriodDelta {
+  current: number
+  previous: number
+  change: number
+  changePercent: number | null
+}
+
+/** Complete VAT Monitor report */
+export interface VatMonitorReport {
+  period: { year: number; month?: number; quarter?: number }
+  boxes: VatBoxData[]
+  revenueBreakdown: RevenueBreakdown
+  vatSummary: {
+    outputVat25: number
+    outputVat12: number
+    outputVat6: number
+    totalOutputVat: number
+    inputVat: number
+    netVat: number
+    isRefund: boolean
+  }
+  warnings: VatMonitorWarning[]
+  comparison: PeriodComparison | null
+}
+
+/** Period-over-period comparison */
+export interface PeriodComparison {
+  domestic: PeriodDelta
+  euGoods: PeriodDelta
+  euServices: PeriodDelta
+  exportGoods: PeriodDelta
+  exportServices: PeriodDelta
+  triangular: PeriodDelta
+  totalRevenue: PeriodDelta
+  netVat: PeriodDelta
+}
+
+/** Options for generating the VAT Monitor report */
+export interface VatMonitorOptions {
+  glLines: GLLine[]
+  invoices?: VatMonitorInvoice[]
+  customers?: VatMonitorCustomer[]
+  year: number
+  month?: number
+  quarter?: number
+  previousGlLines?: GLLine[]
+}
+
+// ── Revenue account groups ──────────────────────────────────
+
+const DOMESTIC_ACCOUNTS = ['3001', '3002', '3003']
+const EU_GOODS_ACCOUNTS = ['3108', '3521']
+const EU_SERVICES_ACCOUNTS = ['3308']
+const EXPORT_GOODS_ACCOUNTS = ['3105', '3522']
+const EXPORT_SERVICES_ACCOUNTS = ['3305']
+const TRIANGULATION_ACCOUNTS = ['3109']
+
+const OUTPUT_VAT_ACCOUNTS: Record<string, string> = {
+  '2611': '25%',
+  '2621': '12%',
+  '2631': '6%',
+}
+
+const INPUT_VAT_ACCOUNTS = ['2641', '2645']
+
+// All accounts this engine cares about
+const ALL_ACCOUNTS = [
+  ...DOMESTIC_ACCOUNTS,
+  ...EU_GOODS_ACCOUNTS,
+  ...EU_SERVICES_ACCOUNTS,
+  ...EXPORT_GOODS_ACCOUNTS,
+  ...EXPORT_SERVICES_ACCOUNTS,
+  ...TRIANGULATION_ACCOUNTS,
+  ...Object.keys(OUTPUT_VAT_ACCOUNTS),
+  ...INPUT_VAT_ACCOUNTS,
+]
+
+// ── Expected vat_treatment for revenue account groups ───────
+
+const ACCOUNT_EXPECTED_VAT_TREATMENT: Record<string, string[]> = {
+  '3001': ['standard_25'],
+  '3002': ['reduced_12'],
+  '3003': ['reduced_6'],
+  '3108': ['reverse_charge'],
+  '3521': ['reverse_charge'],
+  '3109': ['reverse_charge'],
+  '3308': ['reverse_charge'],
+  '3105': ['export'],
+  '3522': ['export'],
+  '3305': ['export'],
+}
+
+// ── Core engine ──────────────────────────────────────────────
+
+/**
+ * Generate a VAT Monitor report from pre-fetched GL data.
+ */
+export function generateVatMonitorReport(options: VatMonitorOptions): VatMonitorReport {
+  const { glLines, invoices, customers, year, month, quarter, previousGlLines } = options
+
+  const warnings: VatMonitorWarning[] = []
+
+  // Step 1: Aggregate GL lines into account credit balances
+  const accountBalances = aggregateGLLines(glLines)
+
+  // Step 2: Map accounts to boxes
+  const boxes = buildBoxes(accountBalances)
+
+  // Step 3: Calculate revenue breakdown
+  const revenueBreakdown = calculateRevenueBreakdown(accountBalances)
+
+  // Step 4: Calculate VAT summary
+  const vatSummary = calculateVatSummary(accountBalances)
+
+  // Step 5: Validate invoices if provided
+  if (invoices && customers) {
+    validateInvoices(invoices, customers, warnings)
+  }
+
+  // Step 6: Calculate period comparison if previous data provided
+  let comparison: PeriodComparison | null = null
+  if (previousGlLines) {
+    const prevBalances = aggregateGLLines(previousGlLines)
+    const prevBreakdown = calculateRevenueBreakdown(prevBalances)
+    const prevVat = calculateVatSummary(prevBalances)
+    comparison = buildComparison(revenueBreakdown, prevBreakdown, vatSummary.netVat, prevVat.netVat)
+  }
+
+  return {
+    period: { year, month, quarter },
+    boxes,
+    revenueBreakdown,
+    vatSummary,
+    warnings,
+    comparison,
+  }
+}
+
+// ── GL aggregation ──────────────────────────────────────────
+
+/**
+ * Aggregate GL lines into net balances per account.
+ * Revenue accounts: credit balance (credit - debit).
+ * VAT accounts: see sign per account type.
+ */
+function aggregateGLLines(lines: GLLine[]): Map<string, number> {
+  const balances = new Map<string, number>()
+
+  for (const line of lines) {
+    if (!ALL_ACCOUNTS.includes(line.account_number)) continue
+
+    const credit = Number(line.credit_amount) || 0
+    const debit = Number(line.debit_amount) || 0
+
+    // Input VAT is debit-side, all others are credit-side
+    const isInputVat = INPUT_VAT_ACCOUNTS.includes(line.account_number)
+    const balance = isInputVat ? (debit - credit) : (credit - debit)
+
+    balances.set(
+      line.account_number,
+      round2((balances.get(line.account_number) ?? 0) + balance),
+    )
+  }
+
+  return balances
+}
+
+/** Sum balances for a set of accounts */
+function sumAccounts(balances: Map<string, number>, accounts: string[]): number {
+  return round2(accounts.reduce((sum, acc) => sum + (balances.get(acc) ?? 0), 0))
+}
+
+// ── Box building ────────────────────────────────────────────
+
+function buildBoxes(balances: Map<string, number>): VatBoxData[] {
+  // Group accounts by box
+  const boxAccounts = new Map<MomsBox, string[]>()
+  const boxAmounts = new Map<MomsBox, number>()
+
+  for (const [account, balance] of balances) {
+    const box = ACCOUNT_TO_BOX[account]
+    if (!box) continue
+
+    if (!boxAccounts.has(box)) boxAccounts.set(box, [])
+    boxAccounts.get(box)!.push(account)
+
+    boxAmounts.set(box, round2((boxAmounts.get(box) ?? 0) + balance))
+  }
+
+  // Build sorted box list
+  const boxes: VatBoxData[] = []
+  for (const [box, amount] of boxAmounts) {
+    boxes.push({
+      boxNumber: box,
+      label: BOX_LABELS[box],
+      amount: round2(amount),
+      accounts: boxAccounts.get(box) ?? [],
+    })
+  }
+
+  // Add box 49 (net VAT = output - input)
+  const outputVat = sumAccounts(balances, Object.keys(OUTPUT_VAT_ACCOUNTS))
+  const inputVat = sumAccounts(balances, INPUT_VAT_ACCOUNTS)
+  const netVat = round2(outputVat - inputVat)
+
+  boxes.push({
+    boxNumber: '49',
+    label: BOX_LABELS['49'],
+    amount: netVat,
+    accounts: [...Object.keys(OUTPUT_VAT_ACCOUNTS), ...INPUT_VAT_ACCOUNTS],
+  })
+
+  // Sort by box number
+  boxes.sort((a, b) => a.boxNumber.localeCompare(b.boxNumber))
+
+  return boxes
+}
+
+// ── Revenue breakdown ───────────────────────────────────────
+
+function calculateRevenueBreakdown(balances: Map<string, number>): RevenueBreakdown {
+  const domestic = sumAccounts(balances, DOMESTIC_ACCOUNTS)
+  const euGoods = sumAccounts(balances, EU_GOODS_ACCOUNTS)
+  const euServices = sumAccounts(balances, EU_SERVICES_ACCOUNTS)
+  const exportGoods = sumAccounts(balances, EXPORT_GOODS_ACCOUNTS)
+  const exportServices = sumAccounts(balances, EXPORT_SERVICES_ACCOUNTS)
+  const triangular = sumAccounts(balances, TRIANGULATION_ACCOUNTS)
+
+  const totalRevenue = round2(domestic + euGoods + euServices + exportGoods + exportServices + triangular)
+
+  const pct = (amount: number) => totalRevenue > 0 ? round2((amount / totalRevenue) * 100) : 0
+
+  return {
+    domestic: { amount: domestic, percentage: pct(domestic) },
+    euGoods: { amount: euGoods, percentage: pct(euGoods) },
+    euServices: { amount: euServices, percentage: pct(euServices) },
+    exportGoods: { amount: exportGoods, percentage: pct(exportGoods) },
+    exportServices: { amount: exportServices, percentage: pct(exportServices) },
+    triangular: { amount: triangular, percentage: pct(triangular) },
+    totalRevenue,
+  }
+}
+
+// ── VAT summary ─────────────────────────────────────────────
+
+function calculateVatSummary(balances: Map<string, number>) {
+  const outputVat25 = balances.get('2611') ?? 0
+  const outputVat12 = balances.get('2621') ?? 0
+  const outputVat6 = balances.get('2631') ?? 0
+  const totalOutputVat = round2(outputVat25 + outputVat12 + outputVat6)
+  const inputVat = sumAccounts(balances, INPUT_VAT_ACCOUNTS)
+  const netVat = round2(totalOutputVat - inputVat)
+
+  return {
+    outputVat25: round2(outputVat25),
+    outputVat12: round2(outputVat12),
+    outputVat6: round2(outputVat6),
+    totalOutputVat,
+    inputVat: round2(inputVat),
+    netVat,
+    isRefund: netVat < 0,
+  }
+}
+
+// ── Invoice validation ──────────────────────────────────────
+
+function validateInvoices(
+  invoices: VatMonitorInvoice[],
+  customers: VatMonitorCustomer[],
+  warnings: VatMonitorWarning[],
+) {
+  const customerMap = new Map(customers.map(c => [c.id, c]))
+
+  for (const invoice of invoices) {
+    const customer = customerMap.get(invoice.customer_id)
+
+    // Check: reverse_charge invoices should have EU customer with VAT number
+    if (invoice.vat_treatment === 'reverse_charge' && customer) {
+      if (!customer.vat_number) {
+        warnings.push({
+          type: 'missing_vat_number',
+          severity: 'error',
+          invoiceId: invoice.id,
+          invoiceNumber: invoice.invoice_number,
+          customerName: customer.name,
+          message: `Faktura ${invoice.invoice_number} (${customer.name}) har omvänd skattskyldighet men kunden saknar VAT-nummer.`,
+        })
+      } else if (!customer.vat_number_validated) {
+        warnings.push({
+          type: 'unvalidated_vat_number',
+          severity: 'warning',
+          invoiceId: invoice.id,
+          invoiceNumber: invoice.invoice_number,
+          customerName: customer.name,
+          message: `Faktura ${invoice.invoice_number} (${customer.name}): VAT-nummer ${customer.vat_number} har inte validerats via VIES.`,
+        })
+      }
+    }
+
+    // Check: moms_ruta consistency with vat_treatment
+    if (invoice.moms_ruta && invoice.vat_treatment) {
+      const expectedBoxes = getExpectedBoxesForTreatment(invoice.vat_treatment)
+      if (expectedBoxes.length > 0 && !expectedBoxes.includes(invoice.moms_ruta)) {
+        warnings.push({
+          type: 'vat_treatment_mismatch',
+          severity: 'warning',
+          invoiceId: invoice.id,
+          invoiceNumber: invoice.invoice_number,
+          message: `Faktura ${invoice.invoice_number} har momsbehandling "${invoice.vat_treatment}" men moms_ruta "${invoice.moms_ruta}" (förväntat: ${expectedBoxes.join('/')}).`,
+        })
+      }
+    }
+  }
+}
+
+/** Get expected momsdeklaration boxes for a vat_treatment value */
+function getExpectedBoxesForTreatment(vatTreatment: string): string[] {
+  switch (vatTreatment) {
+    case 'standard_25':
+    case 'reduced_12':
+    case 'reduced_6':
+      return ['05']
+    case 'reverse_charge':
+      return ['35', '38', '39']
+    case 'export':
+      return ['36', '40']
+    default:
+      return []
+  }
+}
+
+// ── Period comparison ───────────────────────────────────────
+
+function buildComparison(
+  current: RevenueBreakdown,
+  previous: RevenueBreakdown,
+  currentNetVat: number,
+  previousNetVat: number,
+): PeriodComparison {
+  return {
+    domestic: makeDelta(current.domestic.amount, previous.domestic.amount),
+    euGoods: makeDelta(current.euGoods.amount, previous.euGoods.amount),
+    euServices: makeDelta(current.euServices.amount, previous.euServices.amount),
+    exportGoods: makeDelta(current.exportGoods.amount, previous.exportGoods.amount),
+    exportServices: makeDelta(current.exportServices.amount, previous.exportServices.amount),
+    triangular: makeDelta(current.triangular.amount, previous.triangular.amount),
+    totalRevenue: makeDelta(current.totalRevenue, previous.totalRevenue),
+    netVat: makeDelta(currentNetVat, previousNetVat),
+  }
+}
+
+function makeDelta(current: number, previous: number): PeriodDelta {
+  const change = round2(current - previous)
+  const changePercent = previous !== 0 ? round2((change / Math.abs(previous)) * 100) : null
+
+  return { current, previous, change, changePercent }
+}
+
+// ── Helpers ─────────────────────────────────────────────────
+
+function round2(value: number): number {
+  return Math.round(value * 100) / 100
+}
+
+// ── Exported constants for API route ────────────────────────
+
+/** All BAS accounts that the VAT Monitor needs from GL */
+export const VAT_MONITOR_ACCOUNTS = ALL_ACCOUNTS

lib/api/schemas.ts

@@ -506,6 +506,15 @@ export const ReportPeriodQuerySchema = z.object({
   month: z.coerce.number().int().min(1).max(12).optional(),
 })
 
+// ============================================================
+// VAT validation schemas
+// ============================================================
+
+export const ValidateVatNumberSchema = z.object({
+  vat_number: z.string().min(4, 'VAT number must be at least 4 characters'),
+  customer_id: uuid.optional(),
+})
+
 // ============================================================
 // Pagination schemas
 // ============================================================

lib/bookkeeping/bas-reference.ts

@@ -1015,6 +1015,38 @@ export const BAS_REFERENCE: BASReferenceAccount[] = [
     sru_code: '7311',
   },
 
+  // 31 - Forsaljning varor utanfor Sverige
+  {
+    account_number: '3105',
+    account_name: 'Forsaljning varor export utanfor EU',
+    account_class: 3,
+    account_group: '31',
+    account_type: 'revenue',
+    normal_balance: 'credit',
+    description: 'Intakter fran forsaljning av varor till kunder utanfor EU. Momsfritt (momsdeklaration ruta 36).',
+    sru_code: '7310',
+  },
+  {
+    account_number: '3108',
+    account_name: 'Forsaljning varor till annat EU-land',
+    account_class: 3,
+    account_group: '31',
+    account_type: 'revenue',
+    normal_balance: 'credit',
+    description: 'Intakter fran forsaljning av varor till momsregistrerade foretag i andra EU-lander. Omvand skattskyldighet (momsdeklaration ruta 35).',
+    sru_code: '7310',
+  },
+  {
+    account_number: '3109',
+    account_name: 'Forsaljning vid trepartshandel',
+    account_class: 3,
+    account_group: '31',
+    account_type: 'revenue',
+    normal_balance: 'credit',
+    description: 'Mellanmans forsaljning av varor vid trepartshandel inom EU (momsdeklaration ruta 38).',
+    sru_code: '7310',
+  },
+
   // 33 - Forsaljning tjanster utanfor Sverige
   {
     account_number: '3305',
@@ -1037,6 +1069,28 @@ export const BAS_REFERENCE: BASReferenceAccount[] = [
     sru_code: '7310',
   },
 
+  // 35 - Fakturerade kostnader och frakter
+  {
+    account_number: '3521',
+    account_name: 'Fakturerade frakter, EU-land',
+    account_class: 3,
+    account_group: '35',
+    account_type: 'revenue',
+    normal_balance: 'credit',
+    description: 'Fraktkostnader som vidarefaktureras till kunder i andra EU-lander. Foljer varans momsbehandling.',
+    sru_code: '7310',
+  },
+  {
+    account_number: '3522',
+    account_name: 'Fakturerade frakter, export',
+    account_class: 3,
+    account_group: '35',
+    account_type: 'revenue',
+    normal_balance: 'credit',
+    description: 'Fraktkostnader som vidarefaktureras till kunder utanfor EU. Momsfritt (momsdeklaration ruta 36).',
+    sru_code: '7310',
+  },
+
   // 35 - Fakturerade kostnader
   {
     account_number: '3510',

lib/currency/__tests__/riksbanken.test.ts

@@ -0,0 +1,288 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import {
+  fetchExchangeRate,
+  fetchMultipleRates,
+  fetchRateRange,
+  fetchLatestRate,
+  convertToSEK,
+  formatCurrencyAmount,
+} from '../riksbanken'
+
+// Mock logger to suppress output
+vi.mock('@/lib/logger', () => ({
+  createLogger: () => ({
+    info: vi.fn(),
+    warn: vi.fn(),
+    error: vi.fn(),
+  }),
+}))
+
+describe('fetchExchangeRate', () => {
+  beforeEach(() => {
+    vi.restoreAllMocks()
+  })
+
+  it('returns rate 1 for SEK without fetching', async () => {
+    const fetchSpy = vi.spyOn(global, 'fetch')
+    const result = await fetchExchangeRate('SEK')
+
+    expect(result).toEqual({
+      currency: 'SEK',
+      rate: 1,
+      date: expect.stringMatching(/^\d{4}-\d{2}-\d{2}$/),
+    })
+    expect(fetchSpy).not.toHaveBeenCalled()
+  })
+
+  it('parses EUR rate from API response', async () => {
+    vi.spyOn(global, 'fetch').mockResolvedValueOnce(
+      new Response(JSON.stringify([{ value: '11.42', date: '2025-01-15' }]), { status: 200 })
+    )
+
+    const result = await fetchExchangeRate('EUR', new Date('2025-01-15'))
+
+    expect(result).toEqual({
+      currency: 'EUR',
+      rate: 11.42,
+      date: '2025-01-15',
+    })
+  })
+
+  it('returns fallback rate on fetch error', async () => {
+    vi.spyOn(global, 'fetch').mockRejectedValueOnce(new Error('Network error'))
+
+    const result = await fetchExchangeRate('EUR')
+
+    expect(result).not.toBeNull()
+    expect(result!.currency).toBe('EUR')
+    expect(result!.rate).toBeGreaterThan(0)
+  })
+
+  it('tries fallback URL when primary returns non-200', async () => {
+    vi.spyOn(global, 'fetch')
+      .mockResolvedValueOnce(new Response('Not Found', { status: 404 }))
+      .mockResolvedValueOnce(
+        new Response(JSON.stringify([
+          { value: '10.80', date: '2025-01-13' },
+          { value: '10.85', date: '2025-01-14' },
+        ]), { status: 200 })
+      )
+
+    const result = await fetchExchangeRate('USD', new Date('2025-01-15'))
+
+    expect(result).toEqual({
+      currency: 'USD',
+      rate: 10.85,
+      date: '2025-01-14',
+    })
+  })
+})
+
+describe('fetchMultipleRates', () => {
+  beforeEach(() => {
+    vi.restoreAllMocks()
+  })
+
+  it('returns Map with all requested currencies', async () => {
+    vi.spyOn(global, 'fetch')
+      .mockResolvedValueOnce(
+        new Response(JSON.stringify([{ value: '11.42', date: '2025-01-15' }]), { status: 200 })
+      )
+      .mockResolvedValueOnce(
+        new Response(JSON.stringify([{ value: '10.50', date: '2025-01-15' }]), { status: 200 })
+      )
+
+    const result = await fetchMultipleRates(['EUR', 'USD'])
+
+    expect(result.size).toBe(3) // EUR, USD, + always SEK
+    expect(result.get('SEK')!.rate).toBe(1)
+    expect(result.get('EUR')!.rate).toBe(11.42)
+    expect(result.get('USD')!.rate).toBe(10.50)
+  })
+
+  it('handles partial failure — returns fallback for failed currencies', async () => {
+    vi.spyOn(global, 'fetch')
+      .mockResolvedValueOnce(
+        new Response(JSON.stringify([{ value: '11.42', date: '2025-01-15' }]), { status: 200 })
+      )
+      .mockRejectedValueOnce(new Error('Network error'))
+
+    const result = await fetchMultipleRates(['EUR', 'GBP'])
+
+    expect(result.size).toBe(3)
+    expect(result.get('EUR')!.rate).toBe(11.42)
+    // GBP gets fallback rate (from the catch in fetchExchangeRate)
+    expect(result.get('GBP')).toBeDefined()
+    expect(result.get('GBP')!.rate).toBeGreaterThan(0)
+  })
+
+  it('returns only SEK when given empty array', async () => {
+    const result = await fetchMultipleRates([])
+    expect(result.size).toBe(1)
+    expect(result.get('SEK')!.rate).toBe(1)
+  })
+
+  it('handles SEK in the input array without duplicate fetch', async () => {
+    vi.spyOn(global, 'fetch').mockResolvedValueOnce(
+      new Response(JSON.stringify([{ value: '11.42', date: '2025-01-15' }]), { status: 200 })
+    )
+
+    const result = await fetchMultipleRates(['SEK', 'EUR'])
+
+    expect(result.size).toBe(2)
+    expect(result.get('SEK')!.rate).toBe(1)
+    expect(result.get('EUR')!.rate).toBe(11.42)
+  })
+})
+
+describe('fetchRateRange', () => {
+  beforeEach(() => {
+    vi.restoreAllMocks()
+  })
+
+  it('returns sorted array of rates', async () => {
+    vi.spyOn(global, 'fetch').mockResolvedValueOnce(
+      new Response(JSON.stringify([
+        { value: '11.40', date: '2025-01-13' },
+        { value: '11.45', date: '2025-01-15' },
+        { value: '11.42', date: '2025-01-14' },
+      ]), { status: 200 })
+    )
+
+    const result = await fetchRateRange(
+      'EUR',
+      new Date('2025-01-13'),
+      new Date('2025-01-15')
+    )
+
+    expect(result).toHaveLength(3)
+    expect(result[0].date).toBe('2025-01-13')
+    expect(result[1].date).toBe('2025-01-14')
+    expect(result[2].date).toBe('2025-01-15')
+  })
+
+  it('returns [rate:1] for SEK', async () => {
+    const fetchSpy = vi.spyOn(global, 'fetch')
+    const result = await fetchRateRange(
+      'SEK',
+      new Date('2025-01-13'),
+      new Date('2025-01-15')
+    )
+
+    expect(result).toHaveLength(1)
+    expect(result[0].rate).toBe(1)
+    expect(fetchSpy).not.toHaveBeenCalled()
+  })
+
+  it('returns empty array on error', async () => {
+    vi.spyOn(global, 'fetch').mockRejectedValueOnce(new Error('Network error'))
+
+    const result = await fetchRateRange(
+      'EUR',
+      new Date('2025-01-13'),
+      new Date('2025-01-15')
+    )
+
+    expect(result).toEqual([])
+  })
+
+  it('returns empty array on non-200 response', async () => {
+    vi.spyOn(global, 'fetch').mockResolvedValueOnce(
+      new Response('Not Found', { status: 404 })
+    )
+
+    const result = await fetchRateRange(
+      'EUR',
+      new Date('2025-01-13'),
+      new Date('2025-01-15')
+    )
+
+    expect(result).toEqual([])
+  })
+})
+
+describe('fetchLatestRate', () => {
+  beforeEach(() => {
+    vi.restoreAllMocks()
+  })
+
+  it('returns the last item from API response', async () => {
+    vi.spyOn(global, 'fetch').mockResolvedValueOnce(
+      new Response(JSON.stringify([
+        { value: '11.40', date: '2025-01-13' },
+        { value: '11.42', date: '2025-01-14' },
+        { value: '11.45', date: '2025-01-15' },
+      ]), { status: 200 })
+    )
+
+    const result = await fetchLatestRate('EUR')
+
+    expect(result).toEqual({
+      currency: 'EUR',
+      rate: 11.45,
+      date: '2025-01-15',
+    })
+  })
+
+  it('returns rate 1 for SEK', async () => {
+    const fetchSpy = vi.spyOn(global, 'fetch')
+    const result = await fetchLatestRate('SEK')
+
+    expect(result).toEqual({
+      currency: 'SEK',
+      rate: 1,
+      date: expect.stringMatching(/^\d{4}-\d{2}-\d{2}$/),
+    })
+    expect(fetchSpy).not.toHaveBeenCalled()
+  })
+
+  it('returns fallback on error', async () => {
+    vi.spyOn(global, 'fetch').mockRejectedValueOnce(new Error('Network error'))
+
+    const result = await fetchLatestRate('EUR')
+
+    expect(result).not.toBeNull()
+    expect(result!.currency).toBe('EUR')
+    expect(result!.rate).toBeGreaterThan(0)
+  })
+
+  it('returns null on empty API response', async () => {
+    vi.spyOn(global, 'fetch').mockResolvedValueOnce(
+      new Response(JSON.stringify([]), { status: 200 })
+    )
+
+    const result = await fetchLatestRate('EUR')
+
+    expect(result).toBeNull()
+  })
+})
+
+describe('convertToSEK', () => {
+  it('converts amount correctly', () => {
+    expect(convertToSEK(100, 11.42)).toBe(1142)
+  })
+
+  it('handles zero amount', () => {
+    expect(convertToSEK(0, 11.42)).toBe(0)
+  })
+})
+
+describe('formatCurrencyAmount', () => {
+  it('formats EUR with symbol prefix', () => {
+    const result = formatCurrencyAmount(1234.56, 'EUR')
+    // sv-SE uses non-breaking space as thousands separator
+    expect(result).toContain('€')
+    expect(result).toContain('1')
+    expect(result).toContain('234')
+  })
+
+  it('formats SEK with currency suffix', () => {
+    const result = formatCurrencyAmount(1234.56, 'SEK')
+    expect(result).toContain('SEK')
+  })
+
+  it('formats NOK with currency suffix', () => {
+    const result = formatCurrencyAmount(100, 'NOK')
+    expect(result).toContain('NOK')
+  })
+})

lib/currency/riksbanken.ts

@@ -3,6 +3,16 @@ import type { Currency, ExchangeRate } from '@/types'
 
 const log = createLogger('riksbanken')
 
+/** Riksbanken series IDs for each currency */
+const SERIES_IDS: Record<Currency, string> = {
+  SEK: '',
+  EUR: 'SEKEURPMI',
+  USD: 'SEKUSDPMI',
+  GBP: 'SEKGBPPMI',
+  NOK: 'SEKNOKPMI',
+  DKK: 'SEKDKKPMI',
+}
+
 /**
  * Fetch exchange rates from Riksbanken API
  * Uses their public API for daily exchange rates
@@ -22,17 +32,7 @@ export async function fetchExchangeRate(
   const targetDate = date || new Date()
   const formattedDate = targetDate.toISOString().split('T')[0]
 
-  // Riksbanken uses specific series IDs for each currency
-  const seriesIds: Record<Currency, string> = {
-    SEK: '',
-    EUR: 'SEKEURPMI',
-    USD: 'SEKUSDPMI',
-    GBP: 'SEKGBPPMI',
-    NOK: 'SEKNOKPMI',
-    DKK: 'SEKDKKPMI',
-  }
-
-  const seriesId = seriesIds[currency]
+  const seriesId = SERIES_IDS[currency]
   if (!seriesId) {
     log.error(`Unknown currency: ${currency}`)
     return null
@@ -49,9 +49,16 @@ export async function fetchExchangeRate(
       next: { revalidate: 3600 }, // Cache for 1 hour
     })
 
-    if (!response.ok) {
-      // If no rate for the specific date, try getting the latest available
-      const fallbackUrl = `https://api.riksbank.se/swea/v1/Observations/${seriesId}`
+    // 204 = no data for this date (e.g. rate not published yet today)
+    // Also handle non-ok responses by falling back to a recent date range
+    if (!response.ok || response.status === 204) {
+      // Fetch the last 7 days to find the most recent available rate
+      const to = formattedDate
+      const fromDate = new Date(targetDate)
+      fromDate.setDate(fromDate.getDate() - 7)
+      const from = fromDate.toISOString().split('T')[0]
+
+      const fallbackUrl = `https://api.riksbank.se/swea/v1/Observations/${seriesId}/${from}/${to}`
       const fallbackResponse = await fetch(fallbackUrl, {
         headers: {
           Accept: 'application/json',
@@ -59,7 +66,7 @@ export async function fetchExchangeRate(
         next: { revalidate: 3600 },
       })
 
-      if (!fallbackResponse.ok) {
+      if (!fallbackResponse.ok || fallbackResponse.status === 204) {
         throw new Error(`Failed to fetch exchange rate: ${fallbackResponse.status}`)
       }
 
@@ -151,3 +158,145 @@ export function formatCurrencyAmount(
 
   return `${formatted} ${currency}`
 }
+
+/**
+ * Fetch exchange rates for multiple currencies in parallel.
+ * Returns a Map with all requested currencies. Individual failures
+ * use fallback rates so the Map is always fully populated.
+ * SEK is always included with rate 1.
+ */
+export async function fetchMultipleRates(
+  currencies: Currency[],
+  date?: Date
+): Promise<Map<Currency, ExchangeRate>> {
+  const results = new Map<Currency, ExchangeRate>()
+
+  // Always include SEK
+  results.set('SEK', {
+    currency: 'SEK',
+    rate: 1,
+    date: (date || new Date()).toISOString().split('T')[0],
+  })
+
+  const nonSek = currencies.filter(c => c !== 'SEK')
+  if (nonSek.length === 0) return results
+
+  const settled = await Promise.allSettled(
+    nonSek.map(currency => fetchExchangeRate(currency, date))
+  )
+
+  for (let i = 0; i < nonSek.length; i++) {
+    const currency = nonSek[i]
+    const outcome = settled[i]
+
+    if (outcome.status === 'fulfilled' && outcome.value) {
+      results.set(currency, outcome.value)
+    } else {
+      // fetchExchangeRate already returns fallback on error,
+      // but if it returned null or the promise rejected, use fallback
+      results.set(currency, getFallbackRate(currency))
+    }
+  }
+
+  return results
+}
+
+/**
+ * Fetch exchange rates for a currency over a date range.
+ * Uses the Riksbanken date-range endpoint. Returns a sorted array.
+ */
+export async function fetchRateRange(
+  currency: Currency,
+  fromDate: Date,
+  toDate: Date
+): Promise<ExchangeRate[]> {
+  if (currency === 'SEK') {
+    return [{
+      currency: 'SEK',
+      rate: 1,
+      date: fromDate.toISOString().split('T')[0],
+    }]
+  }
+
+  const seriesId = SERIES_IDS[currency]
+  if (!seriesId) {
+    log.error(`Unknown currency: ${currency}`)
+    return []
+  }
+
+  const from = fromDate.toISOString().split('T')[0]
+  const to = toDate.toISOString().split('T')[0]
+
+  try {
+    const url = `https://api.riksbank.se/swea/v1/Observations/${seriesId}/${from}/${to}`
+    const response = await fetch(url, {
+      headers: { Accept: 'application/json' },
+    })
+
+    if (!response.ok) {
+      log.error(`Failed to fetch rate range: ${response.status}`)
+      return []
+    }
+
+    const data = await response.json()
+    if (!Array.isArray(data)) return []
+
+    return data
+      .map((item: { date: string; value: string }) => ({
+        currency,
+        rate: parseFloat(item.value),
+        date: item.date,
+      }))
+      .sort((a: ExchangeRate, b: ExchangeRate) => a.date.localeCompare(b.date))
+  } catch (error) {
+    log.error('Error fetching rate range:', error)
+    return []
+  }
+}
+
+/**
+ * Fetch the latest available exchange rate for a currency.
+ * Useful when today's rate hasn't been published yet.
+ */
+export async function fetchLatestRate(
+  currency: Currency
+): Promise<ExchangeRate | null> {
+  if (currency === 'SEK') {
+    return {
+      currency: 'SEK',
+      rate: 1,
+      date: new Date().toISOString().split('T')[0],
+    }
+  }
+
+  const seriesId = SERIES_IDS[currency]
+  if (!seriesId) {
+    log.error(`Unknown currency: ${currency}`)
+    return null
+  }
+
+  try {
+    const url = `https://api.riksbank.se/swea/v1/Observations/${seriesId}`
+    const response = await fetch(url, {
+      headers: { Accept: 'application/json' },
+    })
+
+    if (!response.ok) {
+      log.error(`Failed to fetch latest rate: ${response.status}`)
+      return null
+    }
+
+    const data = await response.json()
+    if (!Array.isArray(data) || data.length === 0) return null
+
+    const latest = data[data.length - 1]
+    return {
+      currency,
+      rate: parseFloat(latest.value),
+      date: latest.date,
+    }
+  } catch (error) {
+    log.error('Error fetching latest rate:', error)
+    return getFallbackRate(currency)
+  }
+}

lib/extensions/__tests__/sectors.test.ts

@@ -7,12 +7,12 @@ import {
 } from '../sectors'
 
 describe('sectors registry', () => {
-  it('should have 6 sectors', () => {
-    expect(SECTORS.length).toBe(6)
+  it('should have 7 sectors', () => {
+    expect(SECTORS.length).toBe(7)
   })
 
-  it('should have 20 total extensions', () => {
-    expect(getAllExtensions().length).toBe(20)
+  it('should have 22 total extensions', () => {
+    expect(getAllExtensions().length).toBe(22)
   })
 
   it('should have unique slugs within each sector', () => {

lib/extensions/icon-resolver.tsx

@@ -25,6 +25,9 @@ import {
   Layers,
   Puzzle,
   TextSearch,
+  Ship,
+  FileText,
+  Shield,
   type LucideIcon,
 } from 'lucide-react'
 
@@ -55,6 +58,9 @@ const ICON_MAP: Record<string, LucideIcon> = {
   Layers,
   Puzzle,
   TextSearch,
+  Ship,
+  FileText,
+  Shield,
 }
 
 export function resolveIcon(name: string): LucideIcon {

lib/extensions/loader.ts

@@ -8,6 +8,10 @@ import { aiChatExtension } from '@/extensions/general/ai-chat'
 import { invoiceInboxExtension } from '@/extensions/general/invoice-inbox'
 import { calendarExtension } from '@/extensions/general/calendar'
 import { userDescriptionMatchExtension } from '@/extensions/general/user-description-match'
+import { euSalesListExtension } from '@/extensions/export/eu-sales-list'
+import { vatMonitorExtension } from '@/extensions/export/vat-monitor'
+import { intrastatExtension } from '@/extensions/export/intrastat'
+import { currencyReceivablesExtension } from '@/extensions/export/currency-receivables'
 import type { Extension } from './types'
 
 // ── Enable Banking (PSD2) — opt-in extension ───────────────────────────
@@ -33,6 +37,12 @@ const FIRST_PARTY_EXTENSIONS: Extension[] = [
   calendarExtension,
   userDescriptionMatchExtension,
   // enableBankingExtension,  // Uncomment to activate PSD2 bank sync
+
+  // ── Export sector ──────────────────────────────────────────
+  euSalesListExtension,
+  vatMonitorExtension,
+  intrastatExtension,
+  currencyReceivablesExtension,
 ]
 
 let loaded = false

lib/extensions/sectors.ts

@@ -322,6 +322,68 @@ export const SECTORS: Sector[] = [
       },
     ],
   },
+
+  // ── Export ──────────────────────────────────────────────
+  {
+    slug: 'export',
+    name: 'Export & Utrikeshandel',
+    icon: 'Ship',
+    description: 'Branschverktyg för export och utrikeshandel',
+    extensions: [
+      {
+        slug: 'eu-sales-list',
+        name: 'Periodisk sammanställning',
+        sector: 'export',
+        category: 'accounting',
+        icon: 'FileText',
+        dataPattern: 'core',
+        readsCoreTables: ['invoices', 'customers'],
+        hasOwnData: false,
+        description: 'Generera periodisk sammanställning (EC Sales List) för Skatteverket',
+        longDescription:
+          'Sammanställer automatiskt alla momsfria EU-försäljningar grupperat per kund och momsregistreringsnummer. Genererar nedladdningsbar fil (CSV/XML) för uppladdning till Skatteverket. Validerar kundernas VAT-nummer via VIES och flaggar saknade uppgifter. Korsvaliderar mot momsdeklarationens ruta 35 och 39.',
+      },
+      {
+        slug: 'vat-monitor',
+        name: 'Exportmoms-monitor',
+        sector: 'export',
+        category: 'reports',
+        icon: 'Shield',
+        dataPattern: 'core',
+        readsCoreTables: ['journal_entry_lines', 'journal_entries', 'invoices'],
+        hasOwnData: false,
+        description: 'Övervaka momsbehandling för export och EU-handel',
+        longDescription:
+          'Visar intäkter uppdelat på inhemsk försäljning, EU B2B (reverse charge) och export utanför EU. Mappar automatiskt till rätt rutor i momsdeklarationen (ruta 05, 35, 36, 39, 40). Flaggar potentiella fel som saknat momsregistreringsnummer på EU-kunder eller felaktig momsbehandling.',
+      },
+      {
+        slug: 'intrastat',
+        name: 'Intrastat-generator',
+        sector: 'export',
+        category: 'accounting',
+        icon: 'BarChart3',
+        dataPattern: 'both',
+        readsCoreTables: ['invoices', 'customers'],
+        hasOwnData: true,
+        description: 'Generera Intrastat-deklarationer för rapportering till SCB',
+        longDescription:
+          'Tagga produkter med CN-koder (Combined Nomenclature), vikt och ursprungsland. Genererar kompletta Intrastat-deklarationer i CSV-format för uppladdning till SCB:s IDEP.web. Övervakar tröskelvärdet på 12 MSEK för utförsel och varnar när rapporteringsskyldighet uppstår.',
+      },
+      {
+        slug: 'currency-receivables',
+        name: 'Valutafordringar',
+        sector: 'export',
+        category: 'reports',
+        icon: 'TrendingUp',
+        dataPattern: 'core',
+        readsCoreTables: ['invoices', 'journal_entry_lines', 'transactions'],
+        hasOwnData: false,
+        description: 'Övervaka valutaexponering och orealiserade kursvinster/-förluster',
+        longDescription:
+          'Visar öppna kundfordringar per valuta med aktuellt SEK-värde baserat på Riksbankens dagskurser. Beräknar orealiserade valutakursvinster och -förluster. Visar realiserade kursdifferenser per period (konto 3960/7960). Ger en samlad bild av företagets valutarisk.',
+      },
+    ],
+  },
 ]
 
 // ============================================================

lib/extensions/types.ts

@@ -10,7 +10,7 @@ import type { EntityType, RawTransaction, IngestResult } from '@/types'
 export type ExtensionCategory = 'accounting' | 'reports' | 'import' | 'operations'
 
 /** Sector slugs for extension organization */
-export type SectorSlug = 'general' | 'restaurant' | 'construction' | 'hotel' | 'tech' | 'ecommerce'
+export type SectorSlug = 'general' | 'restaurant' | 'construction' | 'hotel' | 'tech' | 'ecommerce' | 'export'
 
 /** How an extension gets its data */
 export type ExtensionDataPattern = 'core' | 'manual' | 'both'

lib/extensions/use-mock-data.ts

@@ -0,0 +1,85 @@
+'use client'
+
+import { useState, useEffect, useCallback } from 'react'
+import { useExtensionData } from './use-extension-data'
+
+interface MockMeta {
+  importedAt: string
+  source: 'csv' | 'json'
+  fileName: string
+  rowCount: number
+}
+
+interface UseMockDataResult<T> {
+  mockReport: T | null
+  isMockActive: boolean
+  isLoading: boolean
+  importedAt: string | null
+  meta: MockMeta | null
+  saveMockData: (report: T, meta: Omit<MockMeta, 'importedAt'>) => Promise<void>
+  clearMockData: () => Promise<void>
+}
+
+export function useMockData<T>(sector: string, slug: string): UseMockDataResult<T> {
+  const { getByKey, save, remove, isLoading } = useExtensionData(sector, slug)
+
+  const [mockReport, setMockReport] = useState<T | null>(null)
+  const [isMockActive, setIsMockActive] = useState(false)
+  const [meta, setMeta] = useState<MockMeta | null>(null)
+
+  // Read mock state from extension data on load
+  useEffect(() => {
+    if (isLoading) return
+
+    const enabledRecord = getByKey('mock:enabled')
+    const reportRecord = getByKey('mock:report')
+    const metaRecord = getByKey('mock:meta')
+
+    if (enabledRecord && (enabledRecord.value as { enabled?: boolean }).enabled && reportRecord) {
+      setIsMockActive(true)
+      setMockReport(reportRecord.value as T)
+      if (metaRecord) {
+        setMeta(metaRecord.value as unknown as MockMeta)
+      }
+    } else {
+      setIsMockActive(false)
+      setMockReport(null)
+      setMeta(null)
+    }
+  }, [isLoading, getByKey])
+
+  const saveMockData = useCallback(async (report: T, metaInput: Omit<MockMeta, 'importedAt'>) => {
+    const fullMeta: MockMeta = {
+      ...metaInput,
+      importedAt: new Date().toISOString(),
+    }
+
+    await save('mock:enabled', { enabled: true })
+    await save('mock:report', report as unknown as Record<string, unknown>)
+    await save('mock:meta', fullMeta as unknown as Record<string, unknown>)
+
+    setIsMockActive(true)
+    setMockReport(report)
+    setMeta(fullMeta)
+  }, [save])
+
+  const clearMockData = useCallback(async () => {
+    await remove('mock:enabled')
+    await remove('mock:report')
+    await remove('mock:meta')
+
+    setIsMockActive(false)
+    setMockReport(null)
+    setMeta(null)
+  }, [remove])
+
+  return {
+    mockReport,
+    isMockActive,
+    isLoading,
+    importedAt: meta?.importedAt ?? null,
+    meta,
+    saveMockData,
+    clearMockData,
+  }
+}

lib/extensions/workspace-registry.tsx

@@ -34,6 +34,11 @@ const WORKSPACES: Record<WorkspaceKey, ComponentType<WorkspaceComponentProps>> =
   // E-commerce
   'ecommerce/shopify-import': dynamic(() => import('@/components/extensions/ecommerce/ShopifyImportWorkspace')),
   'ecommerce/multichannel-revenue': dynamic(() => import('@/components/extensions/ecommerce/MultichannelRevenueWorkspace')),
+  // Export
+  'export/eu-sales-list': dynamic(() => import('@/components/extensions/export/EuSalesListWorkspace')),
+  'export/vat-monitor': dynamic(() => import('@/components/extensions/export/VatMonitorWorkspace')),
+  'export/intrastat': dynamic(() => import('@/components/extensions/export/IntrastatWorkspace')),
+  'export/currency-receivables': dynamic(() => import('@/components/extensions/export/CurrencyReceivablesWorkspace')),
 }
 
 export function getWorkspaceComponent(

lib/vat/__tests__/vies-client.test.ts

@@ -0,0 +1,171 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { parseVatNumber, validateVatFormat, validateVatNumber } from '../vies-client'
+
+// Mock logger to suppress output
+vi.mock('@/lib/logger', () => ({
+  createLogger: () => ({
+    info: vi.fn(),
+    warn: vi.fn(),
+    error: vi.fn(),
+  }),
+}))
+
+describe('parseVatNumber', () => {
+  it('parses a DE VAT number', () => {
+    const result = parseVatNumber('DE123456789')
+    expect(result).toEqual({ viesPrefix: 'DE', vatNumber: '123456789' })
+  })
+
+  it('parses a SE VAT number', () => {
+    const result = parseVatNumber('SE123456789012')
+    expect(result).toEqual({ viesPrefix: 'SE', vatNumber: '123456789012' })
+  })
+
+  it('maps GR to EL for Greece', () => {
+    const result = parseVatNumber('GR123456789')
+    expect(result).toEqual({ viesPrefix: 'EL', vatNumber: '123456789' })
+  })
+
+  it('accepts EL prefix directly', () => {
+    const result = parseVatNumber('EL123456789')
+    expect(result).toEqual({ viesPrefix: 'EL', vatNumber: '123456789' })
+  })
+
+  it('strips whitespace', () => {
+    const result = parseVatNumber('DE 123 456 789')
+    expect(result).toEqual({ viesPrefix: 'DE', vatNumber: '123456789' })
+  })
+
+  it('converts to uppercase', () => {
+    const result = parseVatNumber('de123456789')
+    expect(result).toEqual({ viesPrefix: 'DE', vatNumber: '123456789' })
+  })
+
+  it('rejects non-EU country prefix', () => {
+    expect(parseVatNumber('US123456789')).toBeNull()
+  })
+
+  it('rejects too-short input', () => {
+    expect(parseVatNumber('DE')).toBeNull()
+  })
+
+  it('parses FR VAT number with letters', () => {
+    const result = parseVatNumber('FRXX999999999')
+    expect(result).toEqual({ viesPrefix: 'FR', vatNumber: 'XX999999999' })
+  })
+})
+
+describe('validateVatFormat', () => {
+  it('validates DE format (9 digits)', () => {
+    expect(validateVatFormat('DE', '123456789')).toBe(true)
+    expect(validateVatFormat('DE', '12345678')).toBe(false)
+    expect(validateVatFormat('DE', '1234567890')).toBe(false)
+  })
+
+  it('validates SE format (12 digits)', () => {
+    expect(validateVatFormat('SE', '123456789012')).toBe(true)
+    expect(validateVatFormat('SE', '12345678901')).toBe(false)
+  })
+
+  it('validates EL (Greece) format (9 digits)', () => {
+    expect(validateVatFormat('EL', '123456789')).toBe(true)
+    expect(validateVatFormat('EL', '12345678')).toBe(false)
+  })
+
+  it('validates AT format (U + 8 digits)', () => {
+    expect(validateVatFormat('AT', 'U12345678')).toBe(true)
+    expect(validateVatFormat('AT', '12345678')).toBe(false)
+  })
+
+  it('validates NL format (9 digits + B + 2 digits)', () => {
+    expect(validateVatFormat('NL', '123456789B12')).toBe(true)
+    expect(validateVatFormat('NL', '123456789A12')).toBe(false)
+  })
+
+  it('validates FR format (2 alphanums + 9 digits)', () => {
+    expect(validateVatFormat('FR', 'XX999999999')).toBe(true)
+    expect(validateVatFormat('FR', '9999999999')).toBe(false) // only 10 chars
+  })
+
+  it('returns false for unknown prefix', () => {
+    expect(validateVatFormat('XX', '123456789')).toBe(false)
+  })
+})
+
+describe('validateVatNumber', () => {
+  beforeEach(() => {
+    vi.restoreAllMocks()
+  })
+
+  it('returns error for non-EU prefix', async () => {
+    const result = await validateVatNumber('US123456789')
+    expect(result.valid).toBe(false)
+    expect(result.error).toContain('non-EU')
+  })
+
+  it('returns error for invalid format without calling VIES', async () => {
+    const fetchSpy = vi.spyOn(global, 'fetch')
+    const result = await validateVatNumber('DE12345') // too short for DE
+    expect(result.valid).toBe(false)
+    expect(result.error).toContain('format')
+    expect(fetchSpy).not.toHaveBeenCalled()
+  })
+
+  it('returns valid result from VIES API', async () => {
+    vi.spyOn(global, 'fetch').mockResolvedValueOnce(
+      new Response(JSON.stringify({
+        isValid: true,
+        name: 'Test Company GmbH',
+        address: 'Berlin, Germany',
+      }), { status: 200 })
+    )
+
+    const result = await validateVatNumber('DE123456789')
+    expect(result.valid).toBe(true)
+    expect(result.name).toBe('Test Company GmbH')
+    expect(result.address).toBe('Berlin, Germany')
+    expect(result.country_code).toBe('DE')
+    expect(result.vat_number).toBe('DE123456789')
+  })
+
+  it('returns invalid result from VIES API', async () => {
+    vi.spyOn(global, 'fetch').mockResolvedValueOnce(
+      new Response(JSON.stringify({ isValid: false }), { status: 200 })
+    )
+
+    const result = await validateVatNumber('DE123456789')
+    expect(result.valid).toBe(false)
+    expect(result.country_code).toBe('DE')
+  })
+
+  it('handles VIES service unavailable (non-200)', async () => {
+    vi.spyOn(global, 'fetch').mockResolvedValueOnce(
+      new Response('Service Unavailable', { status: 503 })
+    )
+
+    const result = await validateVatNumber('DE123456789')
+    expect(result.valid).toBe(false)
+    expect(result.error).toContain('unavailable')
+  })
+
+  it('handles network error gracefully', async () => {
+    vi.spyOn(global, 'fetch').mockRejectedValueOnce(new Error('Network error'))
+
+    const result = await validateVatNumber('DE123456789')
+    expect(result.valid).toBe(false)
+    expect(result.error).toContain('unavailable')
+  })
+
+  it('handles GR→EL mapping in API call', async () => {
+    const fetchSpy = vi.spyOn(global, 'fetch').mockResolvedValueOnce(
+      new Response(JSON.stringify({ isValid: true }), { status: 200 })
+    )
+
+    await validateVatNumber('GR123456789')
+
+    expect(fetchSpy).toHaveBeenCalledWith(
+      expect.stringContaining('/ms/EL/vat/'),
+      expect.any(Object)
+    )
+  })
+})

lib/vat/vies-client.ts

@@ -0,0 +1,147 @@
+import { createLogger } from '@/lib/logger'
+import { EU_COUNTRIES } from '@/extensions/export/shared/eu-countries'
+import type { VatValidationResult } from '@/types'
+
+const log = createLogger('vies-client')
+
+const VIES_TIMEOUT_MS = 10_000
+
+/**
+ * VAT format patterns per VIES country prefix.
+ * Greece uses 'EL' as its VIES prefix (not 'GR').
+ */
+const VAT_FORMAT_PATTERNS: Record<string, RegExp> = {
+  AT: /^U\d{8}$/,
+  BE: /^0\d{9}$/,
+  BG: /^\d{9,10}$/,
+  CY: /^\d{8}[A-Z]$/,
+  CZ: /^\d{8,10}$/,
+  DE: /^\d{9}$/,
+  DK: /^\d{8}$/,
+  EE: /^\d{9}$/,
+  EL: /^\d{9}$/,
+  ES: /^[A-Z0-9]\d{7}[A-Z0-9]$/,
+  FI: /^\d{8}$/,
+  FR: /^[A-Z0-9]{2}\d{9}$/,
+  HR: /^\d{11}$/,
+  HU: /^\d{8}$/,
+  IE: /^[0-9A-Z]{8,9}$/,
+  IT: /^\d{11}$/,
+  LT: /^\d{9,12}$/,
+  LU: /^\d{8}$/,
+  LV: /^\d{11}$/,
+  MT: /^\d{8}$/,
+  NL: /^\d{9}B\d{2}$/,
+  PL: /^\d{10}$/,
+  PT: /^\d{9}$/,
+  RO: /^\d{2,10}$/,
+  SE: /^\d{12}$/,
+  SI: /^\d{8}$/,
+  SK: /^\d{10}$/,
+}
+
+/** Valid VIES prefixes (derived from EU_COUNTRIES vatPrefix values) */
+const VALID_VIES_PREFIXES = new Set(EU_COUNTRIES.map(c => c.vatPrefix))
+
+/**
+ * Parse a raw VAT number into its VIES prefix and numeric part.
+ * Handles the GR → EL mapping automatically.
+ *
+ * @returns `{ viesPrefix, vatNumber }` or `null` if the prefix is not a valid EU country
+ */
+export function parseVatNumber(raw: string): { viesPrefix: string; vatNumber: string } | null {
+  const cleaned = raw.replace(/\s/g, '').toUpperCase()
+
+  if (cleaned.length < 3) return null
+
+  const countryPrefix = cleaned.substring(0, 2)
+  const vatNumber = cleaned.substring(2)
+
+  // Map GR → EL for Greece (VIES uses EL, not GR)
+  let viesPrefix = countryPrefix
+  if (countryPrefix === 'GR') {
+    viesPrefix = 'EL'
+  }
+
+  if (!VALID_VIES_PREFIXES.has(viesPrefix)) {
+    return null
+  }
+
+  return { viesPrefix, vatNumber }
+}
+
+/**
+ * Validate the format of a VAT number against country-specific patterns.
+ */
+export function validateVatFormat(viesPrefix: string, vatNumber: string): boolean {
+  const pattern = VAT_FORMAT_PATTERNS[viesPrefix]
+  if (!pattern) return false
+  return pattern.test(vatNumber)
+}
+
+/**
+ * Validate a VAT number against the EU VIES REST API.
+ *
+ * 1. Parses the prefix and number
+ * 2. Checks format locally
+ * 3. Calls the VIES REST API with a 10s timeout
+ * 4. Returns a VatValidationResult
+ */
+export async function validateVatNumber(rawVatNumber: string): Promise<VatValidationResult> {
+  const parsed = parseVatNumber(rawVatNumber)
+
+  if (!parsed) {
+    return { valid: false, error: 'Invalid or non-EU country prefix' }
+  }
+
+  const { viesPrefix, vatNumber } = parsed
+
+  if (!validateVatFormat(viesPrefix, vatNumber)) {
+    return {
+      valid: false,
+      country_code: viesPrefix,
+      vat_number: `${viesPrefix}${vatNumber}`,
+      error: 'Invalid VAT number format',
+    }
+  }
+
+  try {
+    const controller = new AbortController()
+    const timeout = setTimeout(() => controller.abort(), VIES_TIMEOUT_MS)
+
+    const response = await fetch(
+      `https://ec.europa.eu/taxation_customs/vies/rest-api/ms/${viesPrefix}/vat/${vatNumber}`,
+      {
+        method: 'GET',
+        headers: { Accept: 'application/json' },
+        signal: controller.signal,
+      }
+    )
+
+    clearTimeout(timeout)
+
+    if (!response.ok) {
+      return {
+        valid: false,
+        error: 'VAT validation service unavailable. Please try again later.',
+      }
+    }
+
+    const data = await response.json()
+    const isValid = data.isValid === true
+
+    return {
+      valid: isValid,
+      name: data.name || undefined,
+      address: data.address || undefined,
+      country_code: viesPrefix,
+      vat_number: `${viesPrefix}${vatNumber}`,
+    }
+  } catch (error) {
+    log.error('VIES API error:', error)
+    return {
+      valid: false,
+      error: 'Could not verify VAT number. Service temporarily unavailable.',
+    }
+  }
+}

mock_data/exportmoms-monitor.json

@@ -0,0 +1,56 @@
+{
+  "period": { "year": 2025, "month": 12 },
+  "boxes": [
+    { "boxNumber": "05", "label": "Momspliktiga intakter", "amount": 1850000, "accounts": ["3001", "3002", "3003"] },
+    { "boxNumber": "10", "label": "Utgaende moms 25%", "amount": 375000, "accounts": ["2611"] },
+    { "boxNumber": "11", "label": "Utgaende moms 12%", "amount": 18000, "accounts": ["2621"] },
+    { "boxNumber": "12", "label": "Utgaende moms 6%", "amount": 4500, "accounts": ["2631"] },
+    { "boxNumber": "35", "label": "Varuforsal jning till annat EU-land", "amount": 711500, "accounts": ["3305"] },
+    { "boxNumber": "36", "label": "Tjansteforsal jning till annat EU-land", "amount": 405000, "accounts": ["3308"] },
+    { "boxNumber": "38", "label": "Exportforsal jning utanfor EU", "amount": 230000, "accounts": ["3305"] },
+    { "boxNumber": "39", "label": "Omvand skattskyldighet — inkop", "amount": 60000, "accounts": [] },
+    { "boxNumber": "40", "label": "Inkop varor fran EU", "amount": 185000, "accounts": ["4515"] },
+    { "boxNumber": "48", "label": "Ingaende moms", "amount": 289000, "accounts": ["2641", "2645"] },
+    { "boxNumber": "49", "label": "Moms att betala", "amount": 108500, "accounts": [] }
+  ],
+  "revenueBreakdown": {
+    "domestic": { "amount": 1850000, "percentage": 57 },
+    "euGoods": { "amount": 711500, "percentage": 22 },
+    "euServices": { "amount": 405000, "percentage": 12 },
+    "exportGoods": { "amount": 230000, "percentage": 7 },
+    "exportServices": { "amount": 0, "percentage": 0 },
+    "triangular": { "amount": 54000, "percentage": 2 },
+    "totalRevenue": 3250500
+  },
+  "vatSummary": {
+    "outputVat25": 375000,
+    "outputVat12": 18000,
+    "outputVat6": 4500,
+    "totalOutputVat": 397500,
+    "inputVat": 289000,
+    "netVat": 108500,
+    "isRefund": false
+  },
+  "warnings": [
+    {
+      "type": "box_mismatch",
+      "severity": "warning",
+      "message": "Ruta 39 (omvand skattskyldighet) har 60 000 SEK men inga matchande kontoposter hittades. Kontrollera bokforingen."
+    },
+    {
+      "type": "high_input_vat_ratio",
+      "severity": "warning",
+      "message": "Ingaende moms (289 000 SEK) utgor 73% av utgaende moms. Kontrollera att alla avdrag ar korrekta."
+    }
+  ],
+  "comparison": {
+    "domestic": { "current": 1850000, "previous": 1620000, "change": 230000, "changePercent": 14 },
+    "euGoods": { "current": 711500, "previous": 580000, "change": 131500, "changePercent": 23 },
+    "euServices": { "current": 405000, "previous": 390000, "change": 15000, "changePercent": 4 },
+    "exportGoods": { "current": 230000, "previous": 310000, "change": -80000, "changePercent": -26 },
+    "exportServices": { "current": 0, "previous": 0, "change": 0, "changePercent": null },
+    "triangular": { "current": 54000, "previous": 0, "change": 54000, "changePercent": null },
+    "totalRevenue": { "current": 3250500, "previous": 2900000, "change": 350500, "changePercent": 12 },
+    "netVat": { "current": 108500, "previous": 95200, "change": 13300, "changePercent": 14 }
+  }
+}

mock_data/intrastat-generator.json

@@ -0,0 +1,116 @@
+{
+  "period": { "year": 2025, "month": 12 },
+  "reporterVatNumber": "SE556677889901",
+  "reporterName": "Testbolaget AB",
+  "lines": [
+    {
+      "cnCode": "72163100",
+      "partnerCountry": "DE",
+      "countryOfOrigin": "SE",
+      "transactionNature": "11",
+      "deliveryTerms": "DAP",
+      "invoicedValue": 245000,
+      "netMass": 4500,
+      "supplementaryUnit": null,
+      "supplementaryUnitType": null,
+      "partnerVatId": "DE123456789"
+    },
+    {
+      "cnCode": "84713000",
+      "partnerCountry": "FR",
+      "countryOfOrigin": "CN",
+      "transactionNature": "11",
+      "deliveryTerms": "EXW",
+      "invoicedValue": 128000,
+      "netMass": 85,
+      "supplementaryUnit": 40,
+      "supplementaryUnitType": "st",
+      "partnerVatId": "FR98765432101"
+    },
+    {
+      "cnCode": "39269090",
+      "partnerCountry": "NL",
+      "countryOfOrigin": "SE",
+      "transactionNature": "11",
+      "deliveryTerms": "FCA",
+      "invoicedValue": 78000,
+      "netMass": 620,
+      "supplementaryUnit": null,
+      "supplementaryUnitType": null,
+      "partnerVatId": "NL456789012B01"
+    },
+    {
+      "cnCode": "85176200",
+      "partnerCountry": "FI",
+      "countryOfOrigin": "SE",
+      "transactionNature": "11",
+      "deliveryTerms": "DAP",
+      "invoicedValue": 56000,
+      "netMass": 12,
+      "supplementaryUnit": 200,
+      "supplementaryUnitType": "st",
+      "partnerVatId": "FI12345678"
+    },
+    {
+      "cnCode": "72163100",
+      "partnerCountry": "ES",
+      "countryOfOrigin": "SE",
+      "transactionNature": "11",
+      "deliveryTerms": "CIF",
+      "invoicedValue": 132000,
+      "netMass": 2800,
+      "supplementaryUnit": null,
+      "supplementaryUnitType": null,
+      "partnerVatId": "ES87654321A"
+    },
+    {
+      "cnCode": "73064090",
+      "partnerCountry": "IT",
+      "countryOfOrigin": "SE",
+      "transactionNature": "11",
+      "deliveryTerms": "DAP",
+      "invoicedValue": 67500,
+      "netMass": 1450,
+      "supplementaryUnit": null,
+      "supplementaryUnitType": null,
+      "partnerVatId": "IT01234567890"
+    },
+    {
+      "cnCode": "44079910",
+      "partnerCountry": "PL",
+      "countryOfOrigin": "SE",
+      "transactionNature": "11",
+      "deliveryTerms": "FCA",
+      "invoicedValue": 189000,
+      "netMass": 18600,
+      "supplementaryUnit": null,
+      "supplementaryUnitType": null,
+      "partnerVatId": "PL5678901234"
+    },
+    {
+      "cnCode": "84713000",
+      "partnerCountry": "DE",
+      "countryOfOrigin": "TW",
+      "transactionNature": "11",
+      "deliveryTerms": "DAP",
+      "invoicedValue": 94000,
+      "netMass": 62,
+      "supplementaryUnit": 30,
+      "supplementaryUnitType": "st",
+      "partnerVatId": "DE123456789"
+    }
+  ],
+  "totals": {
+    "invoicedValue": 989500,
+    "netMass": 28129,
+    "lineCount": 8
+  },
+  "thresholdStatus": {
+    "cumulativeValue": 7850000,
+    "threshold": 9000000,
+    "isObligated": false,
+    "percentageUsed": 87
+  },
+  "warnings": [],
+  "invoiceCount": 14
+}

mock_data/periodisk-sammanstallning.json

@@ -0,0 +1,115 @@
+{
+  "period": { "year": 2025, "quarter": 4 },
+  "filingType": "quarterly",
+  "reporterVatNumber": "SE556677889901",
+  "reporterName": "Testbolaget AB",
+  "lines": [
+    {
+      "customerVatNumber": "DE123456789",
+      "customerName": "Berliner Maschinenbau GmbH",
+      "customerCountry": "DE",
+      "customerId": "cust-001",
+      "goodsAmount": 245000,
+      "servicesAmount": 0,
+      "triangulationAmount": 0,
+      "invoiceCount": 4
+    },
+    {
+      "customerVatNumber": "FR98765432101",
+      "customerName": "Lyon Digital SARL",
+      "customerCountry": "FR",
+      "customerId": "cust-002",
+      "goodsAmount": 0,
+      "servicesAmount": 185000,
+      "triangulationAmount": 0,
+      "invoiceCount": 3
+    },
+    {
+      "customerVatNumber": "NL456789012B01",
+      "customerName": "Amsterdam Trading BV",
+      "customerCountry": "NL",
+      "customerId": "cust-003",
+      "goodsAmount": 78000,
+      "servicesAmount": 42000,
+      "triangulationAmount": 0,
+      "invoiceCount": 2
+    },
+    {
+      "customerVatNumber": "FI12345678",
+      "customerName": "Helsinki Solutions Oy",
+      "customerCountry": "FI",
+      "customerId": "cust-004",
+      "goodsAmount": 0,
+      "servicesAmount": 96000,
+      "triangulationAmount": 0,
+      "invoiceCount": 1
+    },
+    {
+      "customerVatNumber": "ES87654321A",
+      "customerName": "Barcelona Componentes SL",
+      "customerCountry": "ES",
+      "customerId": "cust-005",
+      "goodsAmount": 132000,
+      "servicesAmount": 0,
+      "triangulationAmount": 54000,
+      "invoiceCount": 3
+    },
+    {
+      "customerVatNumber": "IT01234567890",
+      "customerName": "Milano Engineering SpA",
+      "customerCountry": "IT",
+      "customerId": "cust-006",
+      "goodsAmount": 67500,
+      "servicesAmount": 28000,
+      "triangulationAmount": 0,
+      "invoiceCount": 2
+    },
+    {
+      "customerVatNumber": "PL5678901234",
+      "customerName": "Warszawa Logistik Sp. z o.o.",
+      "customerCountry": "PL",
+      "customerId": "cust-007",
+      "goodsAmount": 189000,
+      "servicesAmount": 0,
+      "triangulationAmount": 0,
+      "invoiceCount": 5
+    },
+    {
+      "customerVatNumber": "DK12345678",
+      "customerName": "Kobenhavn Konsult ApS",
+      "customerCountry": "DK",
+      "customerId": "cust-008",
+      "goodsAmount": 0,
+      "servicesAmount": 54000,
+      "triangulationAmount": 0,
+      "invoiceCount": 1
+    }
+  ],
+  "totals": {
+    "goods": 711500,
+    "services": 405000,
+    "triangulation": 54000,
+    "total": 1170500
+  },
+  "warnings": [
+    {
+      "type": "missing_vat_validation",
+      "severity": "warning",
+      "customerId": "cust-005",
+      "customerName": "Barcelona Componentes SL",
+      "message": "VAT-nummer ES87654321A har inte validerats mot VIES. Verifiera innan inlämning."
+    }
+  ],
+  "crossCheck": {
+    "box35Match": true,
+    "box35ReportTotal": 711500,
+    "box35GLTotal": 711500,
+    "box39Match": false,
+    "box39ReportTotal": 405000,
+    "box39GLTotal": 403800
+  },
+  "invoiceCount": 21,
+  "customerCount": 8,
+  "deadline": "2026-02-20",
+  "daysUntilDeadline": 14
+}

mock_data/valutafordringar.json

@@ -0,0 +1,245 @@
+{
+  "referenceDate": "2025-12-15",
+  "exchangeRates": [
+    { "currency": "EUR", "rate": 11.4215, "date": "2025-12-15" },
+    { "currency": "USD", "rate": 10.3870, "date": "2025-12-15" },
+    { "currency": "GBP", "rate": 13.5420, "date": "2025-12-15" },
+    { "currency": "NOK", "rate": 0.9845, "date": "2025-12-15" }
+  ],
+  "exposureByCurrency": [
+    {
+      "currency": "EUR",
+      "totalForeignAmount": 48500,
+      "bookedSekValue": 541350,
+      "currentSekValue": 553943,
+      "unrealizedGainLoss": 12593,
+      "invoiceCount": 4,
+      "averageBookedRate": 11.1619,
+      "currentRate": 11.4215
+    },
+    {
+      "currency": "USD",
+      "totalForeignAmount": 72000,
+      "bookedSekValue": 741600,
+      "currentSekValue": 747864,
+      "unrealizedGainLoss": 6264,
+      "invoiceCount": 3,
+      "averageBookedRate": 10.3000,
+      "currentRate": 10.3870
+    },
+    {
+      "currency": "GBP",
+      "totalForeignAmount": 15000,
+      "bookedSekValue": 199500,
+      "currentSekValue": 203130,
+      "unrealizedGainLoss": 3630,
+      "invoiceCount": 1,
+      "averageBookedRate": 13.3000,
+      "currentRate": 13.5420
+    },
+    {
+      "currency": "NOK",
+      "totalForeignAmount": 320000,
+      "bookedSekValue": 316800,
+      "currentSekValue": 315040,
+      "unrealizedGainLoss": -1760,
+      "invoiceCount": 2,
+      "averageBookedRate": 0.9900,
+      "currentRate": 0.9845
+    }
+  ],
+  "receivables": [
+    {
+      "invoiceId": "inv-1001",
+      "invoiceNumber": "1001",
+      "customerName": "Berliner Maschinenbau GmbH",
+      "customerCountry": "DE",
+      "currency": "EUR",
+      "foreignAmount": 22000,
+      "bookedSekAmount": 245300,
+      "bookedRate": 11.15,
+      "currentSekAmount": 251273,
+      "currentRate": 11.4215,
+      "unrealizedGainLoss": 5973,
+      "invoiceDate": "2025-10-15",
+      "dueDate": "2025-12-15",
+      "daysOutstanding": 61
+    },
+    {
+      "invoiceId": "inv-1008",
+      "invoiceNumber": "1008",
+      "customerName": "Lyon Digital SARL",
+      "customerCountry": "FR",
+      "currency": "EUR",
+      "foreignAmount": 14500,
+      "bookedSekAmount": 163050,
+      "bookedRate": 11.245,
+      "currentSekAmount": 165612,
+      "currentRate": 11.4215,
+      "unrealizedGainLoss": 2562,
+      "invoiceDate": "2025-11-05",
+      "dueDate": "2026-01-05",
+      "daysOutstanding": 40
+    },
+    {
+      "invoiceId": "inv-1012",
+      "invoiceNumber": "1012",
+      "customerName": "Amsterdam Trading BV",
+      "customerCountry": "NL",
+      "currency": "EUR",
+      "foreignAmount": 8000,
+      "bookedSekAmount": 89600,
+      "bookedRate": 11.20,
+      "currentSekAmount": 91372,
+      "currentRate": 11.4215,
+      "unrealizedGainLoss": 1772,
+      "invoiceDate": "2025-11-20",
+      "dueDate": "2025-12-20",
+      "daysOutstanding": 25
+    },
+    {
+      "invoiceId": "inv-1015",
+      "invoiceNumber": "1015",
+      "customerName": "Helsinki Solutions Oy",
+      "customerCountry": "FI",
+      "currency": "EUR",
+      "foreignAmount": 4000,
+      "bookedSekAmount": 43400,
+      "bookedRate": 10.85,
+      "currentSekAmount": 45686,
+      "currentRate": 11.4215,
+      "unrealizedGainLoss": 2286,
+      "invoiceDate": "2025-12-01",
+      "dueDate": "2026-01-01",
+      "daysOutstanding": 14
+    },
+    {
+      "invoiceId": "inv-1003",
+      "invoiceNumber": "1003",
+      "customerName": "New York Consulting Inc",
+      "customerCountry": "US",
+      "currency": "USD",
+      "foreignAmount": 35000,
+      "bookedSekAmount": 360500,
+      "bookedRate": 10.30,
+      "currentSekAmount": 363545,
+      "currentRate": 10.3870,
+      "unrealizedGainLoss": 3045,
+      "invoiceDate": "2025-09-28",
+      "dueDate": "2025-11-28",
+      "daysOutstanding": 78
+    },
+    {
+      "invoiceId": "inv-1009",
+      "invoiceNumber": "1009",
+      "customerName": "Chicago Parts LLC",
+      "customerCountry": "US",
+      "currency": "USD",
+      "foreignAmount": 22000,
+      "bookedSekAmount": 224400,
+      "bookedRate": 10.20,
+      "currentSekAmount": 228514,
+      "currentRate": 10.3870,
+      "unrealizedGainLoss": 4114,
+      "invoiceDate": "2025-10-20",
+      "dueDate": "2025-12-20",
+      "daysOutstanding": 56
+    },
+    {
+      "invoiceId": "inv-1018",
+      "invoiceNumber": "1018",
+      "customerName": "San Francisco Tech Corp",
+      "customerCountry": "US",
+      "currency": "USD",
+      "foreignAmount": 15000,
+      "bookedSekAmount": 156700,
+      "bookedRate": 10.4467,
+      "currentSekAmount": 155805,
+      "currentRate": 10.3870,
+      "unrealizedGainLoss": -895,
+      "invoiceDate": "2025-12-05",
+      "dueDate": "2026-02-05",
+      "daysOutstanding": 10
+    },
+    {
+      "invoiceId": "inv-1010",
+      "invoiceNumber": "1010",
+      "customerName": "London Engineering Ltd",
+      "customerCountry": "GB",
+      "currency": "GBP",
+      "foreignAmount": 15000,
+      "bookedSekAmount": 199500,
+      "bookedRate": 13.30,
+      "currentSekAmount": 203130,
+      "currentRate": 13.5420,
+      "unrealizedGainLoss": 3630,
+      "invoiceDate": "2025-11-01",
+      "dueDate": "2026-01-01",
+      "daysOutstanding": 44
+    },
+    {
+      "invoiceId": "inv-1005",
+      "invoiceNumber": "1005",
+      "customerName": "Oslo Shipping AS",
+      "customerCountry": "NO",
+      "currency": "NOK",
+      "foreignAmount": 200000,
+      "bookedSekAmount": 198000,
+      "bookedRate": 0.99,
+      "currentSekAmount": 196900,
+      "currentRate": 0.9845,
+      "unrealizedGainLoss": -1100,
+      "invoiceDate": "2025-10-10",
+      "dueDate": "2025-12-10",
+      "daysOutstanding": 66
+    },
+    {
+      "invoiceId": "inv-1016",
+      "invoiceNumber": "1016",
+      "customerName": "Bergen Industri AS",
+      "customerCountry": "NO",
+      "currency": "NOK",
+      "foreignAmount": 120000,
+      "bookedSekAmount": 118800,
+      "bookedRate": 0.99,
+      "currentSekAmount": 118140,
+      "currentRate": 0.9845,
+      "unrealizedGainLoss": -660,
+      "invoiceDate": "2025-11-22",
+      "dueDate": "2026-01-22",
+      "daysOutstanding": 23
+    }
+  ],
+  "realizedGainLoss": {
+    "year": 2025,
+    "gains": 28450,
+    "losses": 7820,
+    "net": 20630
+  },
+  "monthlyTrend": [
+    { "month": "2025-01", "realizedGains": 1200, "realizedLosses": 0, "netRealized": 1200 },
+    { "month": "2025-02", "realizedGains": 0, "realizedLosses": 890, "netRealized": -890 },
+    { "month": "2025-03", "realizedGains": 3400, "realizedLosses": 0, "netRealized": 3400 },
+    { "month": "2025-04", "realizedGains": 2100, "realizedLosses": 1250, "netRealized": 850 },
+    { "month": "2025-05", "realizedGains": 0, "realizedLosses": 2300, "netRealized": -2300 },
+    { "month": "2025-06", "realizedGains": 4500, "realizedLosses": 0, "netRealized": 4500 },
+    { "month": "2025-07", "realizedGains": 1850, "realizedLosses": 680, "netRealized": 1170 },
+    { "month": "2025-08", "realizedGains": 3200, "realizedLosses": 0, "netRealized": 3200 },
+    { "month": "2025-09", "realizedGains": 5600, "realizedLosses": 1400, "netRealized": 4200 },
+    { "month": "2025-10", "realizedGains": 2800, "realizedLosses": 0, "netRealized": 2800 },
+    { "month": "2025-11", "realizedGains": 1500, "realizedLosses": 1300, "netRealized": 200 },
+    { "month": "2025-12", "realizedGains": 2300, "realizedLosses": 0, "netRealized": 2300 }
+  ],
+  "revalPreview": {
+    "totalUnrealizedGainLoss": 20727,
+    "gains": 22487,
+    "losses": 1760
+  },
+  "totals": {
+    "bookedSekValue": 1799250,
+    "currentSekValue": 1819977,
+    "totalUnrealizedGainLoss": 20727,
+    "receivableCount": 10,
+    "currencyCount": 4
+  }
+}

scripts/seed-export-data.mjs

@@ -0,0 +1,554 @@
+/**
+ * Seed script: populate data for export extensions
+ *
+ * Creates EU customers, foreign-currency invoices, and journal entries
+ * so that all 4 export extensions (EU Sales List, VAT Monitor, Intrastat,
+ * Currency Receivables) have data to display.
+ *
+ * Usage:  node scripts/seed-export-data.mjs
+ */
+
+import { createClient } from '@supabase/supabase-js'
+import 'dotenv/config'
+
+const supabaseUrl = process.env.NEXT_PUBLIC_SUPABASE_URL
+const serviceRoleKey = process.env.SUPABASE_SERVICE_ROLE_KEY
+
+if (!supabaseUrl || !serviceRoleKey) {
+  console.error('Missing NEXT_PUBLIC_SUPABASE_URL or SUPABASE_SERVICE_ROLE_KEY in .env')
+  process.exit(1)
+}
+
+const supabase = createClient(supabaseUrl, serviceRoleKey)
+
+// ── Helpers ─────────────────────────────────────────────────
+
+function round2(n) {
+  return Math.round(n * 100) / 100
+}
+
+function randomId() {
+  return crypto.randomUUID()
+}
+
+function today() {
+  return new Date().toISOString().split('T')[0]
+}
+
+function daysAgo(n) {
+  const d = new Date()
+  d.setDate(d.getDate() - n)
+  return d.toISOString().split('T')[0]
+}
+
+function daysFromNow(n) {
+  const d = new Date()
+  d.setDate(d.getDate() + n)
+  return d.toISOString().split('T')[0]
+}
+
+// ── Main ────────────────────────────────────────────────────
+
+async function main() {
+  // 1. Find the user
+  const { data: { users }, error: usersError } = await supabase.auth.admin.listUsers()
+  if (usersError) {
+    console.error('Failed to list users:', usersError.message)
+    process.exit(1)
+  }
+
+  if (users.length === 0) {
+    console.error('No users found. Please sign up first.')
+    process.exit(1)
+  }
+
+  const user = users[0]
+  const userId = user.id
+  console.log(`Using user: ${user.email} (${userId})`)
+
+  // 2. Ensure company settings exist
+  const { data: company, error: companyError } = await supabase
+    .from('company_settings')
+    .select('*')
+    .eq('user_id', userId)
+    .single()
+
+  if (companyError || !company) {
+    console.error('No company_settings found. Complete onboarding first.')
+    process.exit(1)
+  }
+
+  console.log(`Company: ${company.company_name || '(unnamed)'}`)
+
+  // 3. Ensure fiscal period exists for current year
+  const year = new Date().getFullYear()
+  const periodStart = `${year}-01-01`
+  const periodEnd = `${year}-12-31`
+
+  let { data: fiscalPeriod } = await supabase
+    .from('fiscal_periods')
+    .select('*')
+    .eq('user_id', userId)
+    .lte('period_start', today())
+    .gte('period_end', today())
+    .limit(1)
+    .single()
+
+  if (!fiscalPeriod) {
+    console.log(`Creating fiscal period for ${year}...`)
+    const { data: newPeriod, error: periodError } = await supabase
+      .from('fiscal_periods')
+      .insert({
+        id: randomId(),
+        user_id: userId,
+        name: `Räkenskapsår ${year}`,
+        period_start: periodStart,
+        period_end: periodEnd,
+        is_closed: false,
+      })
+      .select()
+      .single()
+
+    if (periodError) {
+      console.error('Failed to create fiscal period:', periodError.message)
+      process.exit(1)
+    }
+    fiscalPeriod = newPeriod
+  }
+
+  console.log(`Fiscal period: ${fiscalPeriod.name} (${fiscalPeriod.period_start} – ${fiscalPeriod.period_end})`)
+
+  // 4. Create EU customers
+  const customers = [
+    {
+      id: randomId(),
+      user_id: userId,
+      name: 'TechHaus GmbH',
+      customer_type: 'eu_business',
+      email: 'billing@techhaus.de',
+      country: 'Germany',
+      org_number: 'HRB 12345',
+      vat_number: 'DE123456789',
+      vat_number_validated: true,
+      default_payment_terms: 30,
+      address_line1: 'Friedrichstraße 42',
+      postal_code: '10117',
+      city: 'Berlin',
+    },
+    {
+      id: randomId(),
+      user_id: userId,
+      name: 'Suomen Softworks Oy',
+      customer_type: 'eu_business',
+      email: 'invoices@suomensoftworks.fi',
+      country: 'Finland',
+      org_number: '1234567-8',
+      vat_number: 'FI12345678',
+      vat_number_validated: true,
+      default_payment_terms: 30,
+      address_line1: 'Mannerheimintie 10',
+      postal_code: '00100',
+      city: 'Helsinki',
+    },
+    {
+      id: randomId(),
+      user_id: userId,
+      name: 'Oranje Logistics B.V.',
+      customer_type: 'eu_business',
+      email: 'finance@oranjelogistics.nl',
+      country: 'Netherlands',
+      org_number: 'KvK 87654321',
+      vat_number: 'NL123456789B01',
+      vat_number_validated: true,
+      default_payment_terms: 14,
+      address_line1: 'Keizersgracht 120',
+      postal_code: '1015 AA',
+      city: 'Amsterdam',
+    },
+  ]
+
+  console.log('\nCreating 3 EU customers...')
+  const { error: custError } = await supabase.from('customers').insert(customers)
+  if (custError) {
+    console.error('Failed to create customers:', custError.message)
+    process.exit(1)
+  }
+  for (const c of customers) {
+    console.log(`  ✓ ${c.name} (${c.vat_number})`)
+  }
+
+  // 5. Create invoices
+  // Mix of: SEK reverse_charge, EUR reverse_charge, USD
+  const nextNum = company.next_invoice_number || 1
+
+  const invoices = [
+    // Invoice 1: SEK reverse_charge to German customer (for EU Sales List — goods)
+    {
+      id: randomId(),
+      user_id: userId,
+      customer_id: customers[0].id,
+      invoice_number: `${company.invoice_prefix || 'F'}${String(nextNum).padStart(4, '0')}`,
+      invoice_date: daysAgo(20),
+      due_date: daysFromNow(10),
+      status: 'sent',
+      currency: 'SEK',
+      document_type: 'invoice',
+      vat_treatment: 'reverse_charge',
+      vat_rate: 0,
+      subtotal: 85000,
+      subtotal_sek: 85000,
+      vat_amount: 0,
+      vat_amount_sek: 0,
+      total: 85000,
+      total_sek: 85000,
+      exchange_rate: null,
+      moms_ruta: '35',
+      reverse_charge_text: 'Reverse charge – VAT to be accounted for by the recipient according to article 196 Council Directive 2006/112/EC',
+    },
+    // Invoice 2: EUR reverse_charge to Finnish customer (for EU Sales List — services + Currency Receivables)
+    {
+      id: randomId(),
+      user_id: userId,
+      customer_id: customers[1].id,
+      invoice_number: `${company.invoice_prefix || 'F'}${String(nextNum + 1).padStart(4, '0')}`,
+      invoice_date: daysAgo(15),
+      due_date: daysFromNow(15),
+      status: 'sent',
+      currency: 'EUR',
+      document_type: 'invoice',
+      vat_treatment: 'reverse_charge',
+      vat_rate: 0,
+      subtotal: 5000,
+      subtotal_sek: 57500,
+      vat_amount: 0,
+      vat_amount_sek: 0,
+      total: 5000,
+      total_sek: 57500,
+      exchange_rate: 11.50,
+      exchange_rate_date: daysAgo(15),
+      moms_ruta: '39',
+      reverse_charge_text: 'Reverse charge – VAT to be accounted for by the recipient according to article 196 Council Directive 2006/112/EC',
+    },
+    // Invoice 3: EUR reverse_charge to Dutch customer — goods (for EU Sales List + Currency Receivables)
+    {
+      id: randomId(),
+      user_id: userId,
+      customer_id: customers[2].id,
+      invoice_number: `${company.invoice_prefix || 'F'}${String(nextNum + 2).padStart(4, '0')}`,
+      invoice_date: daysAgo(10),
+      due_date: daysFromNow(20),
+      status: 'sent',
+      currency: 'EUR',
+      document_type: 'invoice',
+      vat_treatment: 'reverse_charge',
+      vat_rate: 0,
+      subtotal: 12000,
+      subtotal_sek: 138000,
+      vat_amount: 0,
+      vat_amount_sek: 0,
+      total: 12000,
+      total_sek: 138000,
+      exchange_rate: 11.50,
+      exchange_rate_date: daysAgo(10),
+      moms_ruta: '35',
+      reverse_charge_text: 'Reverse charge – VAT to be accounted for by the recipient according to article 196 Council Directive 2006/112/EC',
+    },
+    // Invoice 4: USD to Dutch customer — overdue (for Currency Receivables)
+    {
+      id: randomId(),
+      user_id: userId,
+      customer_id: customers[2].id,
+      invoice_number: `${company.invoice_prefix || 'F'}${String(nextNum + 3).padStart(4, '0')}`,
+      invoice_date: daysAgo(45),
+      due_date: daysAgo(15),
+      status: 'overdue',
+      currency: 'USD',
+      document_type: 'invoice',
+      vat_treatment: 'reverse_charge',
+      vat_rate: 0,
+      subtotal: 8500,
+      subtotal_sek: 91800,
+      vat_amount: 0,
+      vat_amount_sek: 0,
+      total: 8500,
+      total_sek: 91800,
+      exchange_rate: 10.80,
+      exchange_rate_date: daysAgo(45),
+      moms_ruta: '35',
+      reverse_charge_text: 'Reverse charge – VAT to be accounted for by the recipient according to article 196 Council Directive 2006/112/EC',
+    },
+    // Invoice 5: Paid SEK reverse_charge to Finnish customer (for EU Sales List history)
+    {
+      id: randomId(),
+      user_id: userId,
+      customer_id: customers[1].id,
+      invoice_number: `${company.invoice_prefix || 'F'}${String(nextNum + 4).padStart(4, '0')}`,
+      invoice_date: daysAgo(60),
+      due_date: daysAgo(30),
+      status: 'paid',
+      currency: 'SEK',
+      document_type: 'invoice',
+      vat_treatment: 'reverse_charge',
+      vat_rate: 0,
+      subtotal: 42000,
+      subtotal_sek: 42000,
+      vat_amount: 0,
+      vat_amount_sek: 0,
+      total: 42000,
+      total_sek: 42000,
+      exchange_rate: null,
+      moms_ruta: '39',
+      reverse_charge_text: 'Reverse charge – VAT to be accounted for by the recipient according to article 196 Council Directive 2006/112/EC',
+    },
+  ]
+
+  console.log('\nCreating 5 invoices...')
+  const { error: invError } = await supabase.from('invoices').insert(invoices)
+  if (invError) {
+    console.error('Failed to create invoices:', invError.message)
+    process.exit(1)
+  }
+
+  for (const inv of invoices) {
+    const cust = customers.find(c => c.id === inv.customer_id)
+    console.log(`  ✓ ${inv.invoice_number} — ${cust.name} — ${inv.currency} ${inv.total} (${inv.status})`)
+  }
+
+  // 6. Create invoice items
+  const invoiceItems = [
+    // Invoice 1 items (SEK goods to Germany)
+    { id: randomId(), invoice_id: invoices[0].id, description: 'Industrial sensors batch', quantity: 50, unit: 'st', unit_price: 1200, line_total: 60000, sort_order: 1 },
+    { id: randomId(), invoice_id: invoices[0].id, description: 'Installation & calibration', quantity: 10, unit: 'tim', unit_price: 2500, line_total: 25000, sort_order: 2 },
+    // Invoice 2 items (EUR services to Finland)
+    { id: randomId(), invoice_id: invoices[1].id, description: 'Software consulting', quantity: 40, unit: 'tim', unit_price: 125, line_total: 5000, sort_order: 1 },
+    // Invoice 3 items (EUR goods to Netherlands)
+    { id: randomId(), invoice_id: invoices[2].id, description: 'Steel components CN:72163100', quantity: 200, unit: 'st', unit_price: 45, line_total: 9000, sort_order: 1 },
+    { id: randomId(), invoice_id: invoices[2].id, description: 'Aluminium fittings CN:76169990', quantity: 100, unit: 'st', unit_price: 30, line_total: 3000, sort_order: 2 },
+    // Invoice 4 items (USD goods to Netherlands)
+    { id: randomId(), invoice_id: invoices[3].id, description: 'Custom machine parts', quantity: 25, unit: 'st', unit_price: 340, line_total: 8500, sort_order: 1 },
+    // Invoice 5 items (SEK services to Finland)
+    { id: randomId(), invoice_id: invoices[4].id, description: 'IT architecture review', quantity: 24, unit: 'tim', unit_price: 1750, line_total: 42000, sort_order: 1 },
+  ]
+
+  const { error: itemsError } = await supabase.from('invoice_items').insert(invoiceItems)
+  if (itemsError) {
+    console.error('Failed to create invoice items:', itemsError.message)
+    process.exit(1)
+  }
+  console.log(`  ✓ ${invoiceItems.length} invoice items created`)
+
+  // Update next_invoice_number
+  await supabase
+    .from('company_settings')
+    .update({ next_invoice_number: nextNum + 5 })
+    .eq('user_id', userId)
+
+  // 7. Create journal entries for the invoices (reverse charge: debit 1510, credit 3305/3308)
+  // These are needed for VAT Monitor and EU Sales List cross-check
+  const journalEntries = []
+  const journalLines = []
+
+  // Get current max voucher number
+  const { data: maxVoucher } = await supabase
+    .from('journal_entries')
+    .select('voucher_number')
+    .eq('user_id', userId)
+    .order('voucher_number', { ascending: false })
+    .limit(1)
+    .single()
+
+  let voucherNum = (maxVoucher?.voucher_number || 0) + 1
+
+  for (const inv of invoices) {
+    const entryId = randomId()
+    const totalSEK = inv.total_sek
+
+    // Determine revenue account: goods = 3305, services = 3308
+    // moms_ruta 35 = goods, 39 = services
+    const revenueAccount = inv.moms_ruta === '35' ? '3305' : '3308'
+
+    journalEntries.push({
+      id: entryId,
+      user_id: userId,
+      fiscal_period_id: fiscalPeriod.id,
+      voucher_number: voucherNum++,
+      voucher_series: 'A',
+      entry_date: inv.invoice_date,
+      description: `Faktura ${inv.invoice_number} — ${customers.find(c => c.id === inv.customer_id).name}`,
+      source_type: 'invoice_created',
+      source_id: inv.id,
+      status: 'posted',
+      committed_at: new Date().toISOString(),
+    })
+
+    // Debit 1510 (accounts receivable)
+    journalLines.push({
+      id: randomId(),
+      journal_entry_id: entryId,
+      account_number: '1510',
+      debit_amount: round2(totalSEK),
+      credit_amount: 0,
+      currency: inv.currency,
+      amount_in_currency: inv.currency !== 'SEK' ? inv.total : null,
+      exchange_rate: inv.exchange_rate,
+      line_description: `Kundfordran ${inv.invoice_number}`,
+      sort_order: 1,
+    })
+
+    // Credit revenue account (3305 export goods or 3308 EU services)
+    journalLines.push({
+      id: randomId(),
+      journal_entry_id: entryId,
+      account_number: revenueAccount,
+      debit_amount: 0,
+      credit_amount: round2(totalSEK),
+      currency: 'SEK',
+      line_description: `Intäkt ${inv.invoice_number}`,
+      sort_order: 2,
+    })
+  }
+
+  // Add a payment entry for invoice 5 (paid) — debit 1930, credit 1510
+  const paymentEntryId = randomId()
+  journalEntries.push({
+    id: paymentEntryId,
+    user_id: userId,
+    fiscal_period_id: fiscalPeriod.id,
+    voucher_number: voucherNum++,
+    voucher_series: 'A',
+    entry_date: daysAgo(25),
+    description: `Betalning ${invoices[4].invoice_number} — Suomen Softworks Oy`,
+    source_type: 'invoice_paid',
+    source_id: invoices[4].id,
+    status: 'posted',
+    committed_at: new Date().toISOString(),
+  })
+
+  journalLines.push({
+    id: randomId(),
+    journal_entry_id: paymentEntryId,
+    account_number: '1930',
+    debit_amount: 42000,
+    credit_amount: 0,
+    currency: 'SEK',
+    line_description: `Inbetalning ${invoices[4].invoice_number}`,
+    sort_order: 1,
+  })
+
+  journalLines.push({
+    id: randomId(),
+    journal_entry_id: paymentEntryId,
+    account_number: '1510',
+    debit_amount: 0,
+    credit_amount: 42000,
+    currency: 'SEK',
+    line_description: `Reglering ${invoices[4].invoice_number}`,
+    sort_order: 2,
+  })
+
+  // Add a small FX gain entry (for Currency Receivables realized FX)
+  const fxEntryId = randomId()
+  journalEntries.push({
+    id: fxEntryId,
+    user_id: userId,
+    fiscal_period_id: fiscalPeriod.id,
+    voucher_number: voucherNum++,
+    voucher_series: 'A',
+    entry_date: daysAgo(25),
+    description: 'Kursdifferens vid betalning',
+    source_type: 'invoice_paid',
+    status: 'posted',
+    committed_at: new Date().toISOString(),
+  })
+
+  journalLines.push({
+    id: randomId(),
+    journal_entry_id: fxEntryId,
+    account_number: '1930',
+    debit_amount: 450,
+    credit_amount: 0,
+    currency: 'SEK',
+    line_description: 'Valutavinst',
+    sort_order: 1,
+  })
+
+  journalLines.push({
+    id: randomId(),
+    journal_entry_id: fxEntryId,
+    account_number: '3960',
+    debit_amount: 0,
+    credit_amount: 450,
+    currency: 'SEK',
+    line_description: 'Valutakursvinst',
+    sort_order: 2,
+  })
+
+  console.log(`\nCreating ${journalEntries.length} journal entries...`)
+  const { error: jeError } = await supabase.from('journal_entries').insert(journalEntries)
+  if (jeError) {
+    console.error('Failed to create journal entries:', jeError.message)
+    process.exit(1)
+  }
+
+  const { error: jlError } = await supabase.from('journal_entry_lines').insert(journalLines)
+  if (jlError) {
+    console.error('Failed to create journal entry lines:', jlError.message)
+    console.error('Cleaning up journal entries...')
+    await supabase.from('journal_entries').delete().in('id', journalEntries.map(e => e.id))
+    process.exit(1)
+  }
+
+  for (const je of journalEntries) {
+    console.log(`  ✓ A${je.voucher_number} — ${je.description}`)
+  }
+
+  // 8. Add Intrastat product metadata via extension_data
+  console.log('\nCreating Intrastat product registry...')
+  const extensionId = 'export/intrastat'
+  const extensionData = [
+    {
+      user_id: userId,
+      extension_id: extensionId,
+      key: 'product:STEEL-COMP',
+      value: { description: 'Steel components', cn_code: '72163100', net_weight_kg: 2.4, country_of_origin: 'SE' },
+    },
+    {
+      user_id: userId,
+      extension_id: extensionId,
+      key: 'product:ALU-FIT',
+      value: { description: 'Aluminium fittings', cn_code: '76169990', net_weight_kg: 0.8, country_of_origin: 'SE' },
+    },
+    {
+      user_id: userId,
+      extension_id: extensionId,
+      key: 'product:IND-SENSOR',
+      value: { description: 'Industrial sensors', cn_code: '90318080', net_weight_kg: 0.35, country_of_origin: 'SE' },
+    },
+  ]
+
+  const { error: extError } = await supabase.from('extension_data').insert(extensionData)
+  if (extError) {
+    console.error('Warning: Failed to create extension_data (Intrastat products):', extError.message)
+    console.log('  (Export extensions will still work, just Intrastat product registry will be empty)')
+  } else {
+    for (const ed of extensionData) {
+      console.log(`  ✓ ${ed.key} — ${ed.value.description} (CN: ${ed.value.cn_code})`)
+    }
+  }
+
+  // Done
+  console.log('\n════════════════════════════════════════════════════')
+  console.log('  Seed data created successfully!')
+  console.log('════════════════════════════════════════════════════')
+  console.log('\nYou should now see data in:')
+  console.log('  • Periodisk sammanställning (EU Sales List) — 3 EU customers, 5 invoices')
+  console.log('  • Exportmoms-monitor (VAT Monitor) — journal entries on 3305/3308')
+  console.log('  • Intrastat — goods invoices + product registry')
+  console.log('  • Valutafordringar (Currency Receivables) — 3 open EUR/USD invoices')
+  console.log('\nSelect the current month/quarter to see the data.')
+}
+
+main().catch(err => {
+  console.error('Unexpected error:', err)
+  process.exit(1)
+})