feat(invoices): rebuild the invoice editor as the snabbflöde single column (#1654)

* refactor(invoices): extract editor payload builders with parity tests Extract the three near-identical inline payload builders in InvoiceEditor.tsx (handleConfirm, saveDraftData, saveEdit) and the self-billed body mapper into pure functions in lib/invoices/editor-payload.ts. Zero behavioral change: the new lib module carries a 300-case parity suite asserting JSON byte equality against verbatim copies of the legacy inline recipes across the full mode x deduction x dimensions x ore-rounding matrix. This is the byte-compatibility ratchet under the upcoming editor re-layout: the repo renders no components in tests, so the wire bodies are what CI can pin. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> * feat(invoices): rebuild the invoice editor as the snabbflöde single column Reshape InvoiceEditor to the approved prototype: one 640px column with uppercase section labels and honest state marks (RequiredMark asterisks, sage check on a picked customer, muted row counts), a dense in-table rows surface with a unified last-row entry (autocomplete over the artikelregister, italic ghost cells, Enter commits free text and lands in the price cell, ArrowDown+Enter commits an article through the same applyArticle side effects), hover-revealed 24px row controls with 40px coarse-pointer targets and per-row aria-labels, a Förval chip line whose collapsed settings re-surface as chips whenever a value deviates from its default (critical in edit/copy so PATCH never round-trips invisible values), a single ochre next-step line (aria-live polite) that doubles as the invalid-submit focus router, and a sticky bottom action bar with the live total: position sticky in both hosts, never fixed, since DialogContent's transform re-anchors fixed children in bare mode. Behavioral deltas, all pre-decided: the primary action is never disabled pre-click for writable users (viewers keep the lock+tooltip treatment); client-side validation failures route focus instead of toasting; genuine field errors stay terracotta and field-adjacent while the two ochre disclosures (taxed-where-performed, labor-only) demote to muted text; committed free-text rows expose a quiet Spara-som-artikel link; the review dialog lists the applied förval (currency, öre rounding, payment-link state); a freshly committed row gets a brief background settle that collapses under prefers-reduced-motion. ArticleCombobox gains the missing combobox ARIA (listbox/option roles, aria-controls, aria-activedescendant only after explicit arrowing). New pure module invoice-editor-flow.ts pins the next-step priority order, the Förval chip derivation and the suggestion filter with unit tests. All payload builders, submit targets and the VAT baseline refs are untouched. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> * fix(invoices): editor review nits: orphaned keys, housing gate, listbox ARIA Three review findings on the snabbflode editor: - Delete 13 orphaned invoice_editor keys from both message files (subtitle_*, add_row, remove_row, remove_row_aria, details_card_title, save_as_draft_short, validation_toast_*, delivery_date_placeholder); each verified unused on the branch, sv/en parity kept. - Gate the housing next-step on a claimed deduction amount so it matches the ROT/RUT claim card's mount condition: a ROT-flagged line with a zero amount mounts no card, and the ochre link would try to focus an unmounted field. Extracted as deriveRequiresHousing in the flow module with a test proven to fail on the old gate. - Move the entry-row popover hint out of the role=listbox element (listbox children must be options) into a sibling inside the absolute wrapper, referenced via aria-describedby on the combobox input. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> * feat(invoices): drop the in-editor faktura/sjalvfaktura tabs The Ny faktura split button already chooses the mode (?self=1); a second switcher inside the editor was double steering. The mode is now fixed for the editor's lifetime and the heading (Registrera sjalvfaktura) carries the distinction. Orphaned tab keys removed from both message files. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> * fix(invoices): wrap sticky-bar actions so they fit small viewports Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> * fix(invoices): stop dialog grid item overflowing small viewports min-w-0 on the editor root: DialogContent is display:grid, so the row grid's min-w otherwise forces the column past narrow screens. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> * fix(invoices): lift assistant FAB above the standalone editor's action bar The rebuilt editor introduces the first page-level sticky bottom bar; the assistant FAB (fixed, z-30) covered its Spara/Granska buttons on the /invoices/[id]/edit page. The editor now sets body[data-page-bottom-bar] in non-bare mode and AgentTrigger lifts to bottom-20 when it is present. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> --------- Co-authored-by: Jakob Wennberg <311770904+jakobwennberg-oss@users.noreply.github.com> Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
2026-08-18 09:56:35 +02:00
parent 93e99012d7
commit 2b5b813b7a
12 changed files with 2879 additions and 1274 deletions
@@ -0,0 +1,505 @@
+import { describe, it, expect } from 'vitest'
+import {
+  buildInvoiceWritePayload,
+  buildSelfBilledPayload,
+  hasDimensionValues,
+  pruneItemDimensions,
+  sanitizeDeductionItems,
+  stripSelfBillingFields,
+} from '@/lib/invoices/editor-payload'
+
+/**
+ * Payload-parity ratchet for the invoice editor rebuild.
+ *
+ * The "legacy" builders below are verbatim re-implementations of the three
+ * inline payload builders that lived in InvoiceEditor.tsx (handleConfirm,
+ * saveDraftData, saveEdit) and the inline self-billed body mapper, before the
+ * extraction into lib/invoices/editor-payload.ts. Every combination in the
+ * matrix asserts JSON.stringify equality between the extracted builder and
+ * the legacy recipe: what goes over the wire may not change by a byte.
+ */
+
+type Item = {
+  line_type?: 'product' | 'text'
+  description: string
+  quantity: number
+  unit: string
+  unit_price: number
+  vat_rate: number
+  article_id?: string | null
+  revenue_account?: string | null
+  deduction_type?: 'rot' | 'rut' | null
+  labor_hours?: number | null
+  work_type?: string | null
+  housing_designation?: string | null
+  apartment_number?: string | null
+  brf_org_number?: string | null
+  accrual_period_start?: string | null
+  accrual_period_end?: string | null
+  accrual_balance_account?: string | null
+  dimensions?: Record<string, string> | null
+}
+
+type FormData = {
+  customer_id: string
+  invoice_date: string
+  due_date: string
+  delivery_date?: string
+  currency: string
+  document_type: 'invoice' | 'proforma' | 'delivery_note'
+  your_reference?: string
+  our_reference?: string
+  notes?: string
+  payment_link_url?: string
+  payment_link_auto?: boolean
+  external_invoice_number?: string
+  self_billing_agreement_ref?: string
+  received_date?: string
+  deduction_personnummer?: string
+  deduction_housing_designation?: string
+  items: Item[]
+}
+
+// ---------------------------------------------------------------------------
+// Legacy recipes (verbatim from InvoiceEditor.tsx before the extraction)
+// ---------------------------------------------------------------------------
+
+function legacyHasDimensionValues(dims: Record<string, string> | null | undefined): boolean {
+  return !!dims && Object.keys(dims).length > 0
+}
+
+function legacyPruneItemDimensions<T extends { dimensions?: Record<string, string> | null }>(
+  items: T[],
+): T[] {
+  return items.map((item) =>
+    legacyHasDimensionValues(item.dimensions) ? item : { ...item, dimensions: undefined },
+  )
+}
+
+function legacyStripSelfBillingFields(data: FormData): Omit<
+  FormData,
+  'external_invoice_number' | 'self_billing_agreement_ref' | 'received_date'
+> {
+  const {
+    external_invoice_number: _ein,
+    self_billing_agreement_ref: _sbar,
+    received_date: _rd,
+    ...rest
+  } = data
+  return rest
+}
+
+function legacySanitizedItems(items: Item[]) {
+  return legacyPruneItemDimensions(items).map((item) => {
+    if (item.deduction_type) return item
+    const {
+      deduction_type: _dt,
+      labor_hours: _lh,
+      work_type: _wt,
+      housing_designation: _hd,
+      apartment_number: _an,
+      brf_org_number: _bn,
+      ...rest
+    } = item
+    return rest
+  })
+}
+
+/** handleConfirm's inline body (create with review). */
+function legacyCreatePayload(
+  data: FormData,
+  oreRounding: boolean,
+  defaultDims: Record<string, string>,
+) {
+  const anyDeduction = data.items.some((i) => i.deduction_type)
+  return {
+    ...legacyStripSelfBillingFields(data),
+    ore_rounding: oreRounding,
+    default_dimensions: defaultDims,
+    items: legacySanitizedItems(data.items),
+    ...(anyDeduction
+      ? {}
+      : { deduction_personnummer: undefined, deduction_housing_designation: undefined }),
+  }
+}
+
+/** saveDraftData's inline body (create + save_as_draft). */
+function legacyDraftPayload(
+  data: FormData,
+  oreRounding: boolean,
+  defaultDims: Record<string, string>,
+) {
+  const anyDeduction = data.items.some((i) => i.deduction_type)
+  return {
+    ...legacyStripSelfBillingFields(data),
+    save_as_draft: true,
+    ore_rounding: oreRounding,
+    default_dimensions: defaultDims,
+    items: legacySanitizedItems(data.items),
+    ...(anyDeduction
+      ? {}
+      : { deduction_personnummer: undefined, deduction_housing_designation: undefined }),
+  }
+}
+
+/** saveEdit's inline body (PATCH). Identical recipe to create. */
+const legacyEditPayload = legacyCreatePayload
+
+/** handleSelfBilledSubmit's inline body. */
+function legacySelfBilledPayload(data: FormData) {
+  return {
+    customer_id: data.customer_id,
+    external_invoice_number: data.external_invoice_number,
+    self_billing_agreement_ref: data.self_billing_agreement_ref || undefined,
+    invoice_date: data.invoice_date,
+    received_date: data.received_date,
+    due_date: data.due_date,
+    currency: data.currency,
+    notes: data.notes,
+    items: data.items.map((i) => ({
+      description: i.description,
+      quantity: i.quantity,
+      unit: i.unit,
+      unit_price: i.unit_price,
+      vat_rate: i.vat_rate,
+    })),
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Fixtures
+// ---------------------------------------------------------------------------
+
+function plainItem(overrides: Partial<Item> = {}): Item {
+  return {
+    line_type: 'product',
+    description: 'Konsulttid',
+    quantity: 10,
+    unit: 'tim',
+    unit_price: 1200,
+    vat_rate: 25,
+    article_id: null,
+    revenue_account: null,
+    deduction_type: null,
+    labor_hours: null,
+    work_type: null,
+    housing_designation: null,
+    apartment_number: null,
+    brf_org_number: null,
+    accrual_period_start: null,
+    accrual_period_end: null,
+    accrual_balance_account: null,
+    dimensions: null,
+    ...overrides,
+  }
+}
+
+function rotItem(overrides: Partial<Item> = {}): Item {
+  return plainItem({
+    description: 'Målning av fasad',
+    deduction_type: 'rot',
+    labor_hours: 12,
+    work_type: 'malning',
+    housing_designation: 'Stockholm Vasastan 1:23',
+    ...overrides,
+  })
+}
+
+function textItem(overrides: Partial<Item> = {}): Item {
+  return plainItem({
+    line_type: 'text',
+    description: 'Enligt offert 2026-14',
+    quantity: 0,
+    unit: '',
+    unit_price: 0,
+    vat_rate: 0,
+    ...overrides,
+  })
+}
+
+function form(overrides: Partial<FormData> = {}): FormData {
+  return {
+    customer_id: 'cust-1',
+    invoice_date: '2026-08-17',
+    due_date: '2026-09-16',
+    delivery_date: '',
+    currency: 'SEK',
+    document_type: 'invoice',
+    your_reference: 'Anna',
+    our_reference: 'Jakob',
+    notes: 'Tack för samarbetet',
+    payment_link_url: '',
+    payment_link_auto: true,
+    external_invoice_number: '',
+    self_billing_agreement_ref: '',
+    received_date: '',
+    deduction_personnummer: '',
+    deduction_housing_designation: '',
+    items: [plainItem()],
+    ...overrides,
+  }
+}
+
+const jsonOf = (v: unknown) => JSON.stringify(v)
+
+// ---------------------------------------------------------------------------
+// Parity matrix: create / draft / edit x deduction x dimensions x text rows
+// ---------------------------------------------------------------------------
+
+describe('buildInvoiceWritePayload parity with the legacy inline builders', () => {
+  const itemVariants: Array<[string, Item[]]> = [
+    ['plain single line', [plainItem()]],
+    ['ROT deduction line', [rotItem()]],
+    ['mixed rot + plain + text', [rotItem(), plainItem(), textItem()]],
+    [
+      'dimensions: empty bag pruned, non-empty kept',
+      [
+        plainItem({ dimensions: {} }),
+        plainItem({ dimensions: { '1': 'KS01', '6': 'P001' } }),
+      ],
+    ],
+    [
+      'accrual line without deduction keeps accrual fields',
+      [
+        plainItem({
+          accrual_period_start: '2026-09-01',
+          accrual_period_end: '2026-12-31',
+          accrual_balance_account: '2990',
+        }),
+      ],
+    ],
+    [
+      'RUT with per-item override account and dims',
+      [
+        rotItem({
+          deduction_type: 'rut',
+          work_type: 'stadning',
+          revenue_account: '3041',
+          dimensions: { '6': 'P002' },
+        }),
+      ],
+    ],
+  ]
+
+  const formVariants: Array<[string, Partial<FormData>]> = [
+    ['default create form', {}],
+    [
+      'claim fields filled',
+      { deduction_personnummer: '19800101-1234', deduction_housing_designation: 'Berga 2:11' },
+    ],
+    [
+      'self-billing carriers accidentally non-empty are stripped',
+      { external_invoice_number: 'K-99', self_billing_agreement_ref: 'AVT-1', received_date: '2026-08-01' },
+    ],
+    ['EUR proforma with payment link', { currency: 'EUR', document_type: 'proforma', payment_link_url: 'https://buy.stripe.com/x' }],
+  ]
+
+  for (const [itemLabel, items] of itemVariants) {
+    for (const [formLabel, formOverrides] of formVariants) {
+      const data = form({ ...formOverrides, items })
+      const dimsVariants: Array<Record<string, string>> = [{}, { '1': 'KS01' }]
+      for (const oreRounding of [true, false]) {
+        for (const defaultDims of dimsVariants) {
+          it(`create: ${itemLabel} / ${formLabel} / ore=${oreRounding} / dims=${jsonOf(defaultDims)}`, () => {
+            expect(
+              jsonOf(buildInvoiceWritePayload(data, { oreRounding, defaultDims })),
+            ).toBe(jsonOf(legacyCreatePayload(data, oreRounding, defaultDims)))
+          })
+          it(`draft: ${itemLabel} / ${formLabel} / ore=${oreRounding} / dims=${jsonOf(defaultDims)}`, () => {
+            expect(
+              jsonOf(
+                buildInvoiceWritePayload(data, { saveAsDraft: true, oreRounding, defaultDims }),
+              ),
+            ).toBe(jsonOf(legacyDraftPayload(data, oreRounding, defaultDims)))
+          })
+          it(`edit: ${itemLabel} / ${formLabel} / ore=${oreRounding} / dims=${jsonOf(defaultDims)}`, () => {
+            expect(
+              jsonOf(buildInvoiceWritePayload(data, { oreRounding, defaultDims })),
+            ).toBe(jsonOf(legacyEditPayload(data, oreRounding, defaultDims)))
+          })
+        }
+      }
+    }
+  }
+})
+
+describe('buildInvoiceWritePayload semantics', () => {
+  it('drops the self-billing carriers from the wire body', () => {
+    const body = JSON.parse(
+      jsonOf(
+        buildInvoiceWritePayload(
+          form({ external_invoice_number: 'X', self_billing_agreement_ref: 'Y', received_date: '2026-01-01' }),
+          { oreRounding: true, defaultDims: {} },
+        ),
+      ),
+    )
+    expect(body).not.toHaveProperty('external_invoice_number')
+    expect(body).not.toHaveProperty('self_billing_agreement_ref')
+    expect(body).not.toHaveProperty('received_date')
+  })
+
+  it('omits save_as_draft entirely unless requested', () => {
+    const noDraft = buildInvoiceWritePayload(form(), { oreRounding: true, defaultDims: {} })
+    expect('save_as_draft' in noDraft).toBe(false)
+    const draft = buildInvoiceWritePayload(form(), {
+      saveAsDraft: true,
+      oreRounding: true,
+      defaultDims: {},
+    })
+    expect(draft.save_as_draft).toBe(true)
+  })
+
+  it('strips invoice-level personnummer/housing when no line claims a deduction', () => {
+    const body = JSON.parse(
+      jsonOf(
+        buildInvoiceWritePayload(
+          form({
+            deduction_personnummer: '19800101-1234',
+            deduction_housing_designation: 'Berga 2:11',
+            items: [plainItem()],
+          }),
+          { oreRounding: true, defaultDims: {} },
+        ),
+      ),
+    )
+    expect(body).not.toHaveProperty('deduction_personnummer')
+    expect(body).not.toHaveProperty('deduction_housing_designation')
+  })
+
+  it('keeps invoice-level personnummer/housing when any line claims a deduction', () => {
+    const body = JSON.parse(
+      jsonOf(
+        buildInvoiceWritePayload(
+          form({
+            deduction_personnummer: '19800101-1234',
+            deduction_housing_designation: 'Berga 2:11',
+            items: [rotItem(), plainItem()],
+          }),
+          { oreRounding: true, defaultDims: {} },
+        ),
+      ),
+    )
+    expect(body.deduction_personnummer).toBe('19800101-1234')
+    expect(body.deduction_housing_designation).toBe('Berga 2:11')
+  })
+
+  it('privacy-strips the six ROT/RUT fields only from non-deduction lines', () => {
+    const body = JSON.parse(
+      jsonOf(
+        buildInvoiceWritePayload(form({ items: [rotItem(), plainItem()] }), {
+          oreRounding: false,
+          defaultDims: {},
+        }),
+      ),
+    )
+    expect(body.items[0].deduction_type).toBe('rot')
+    expect(body.items[0].labor_hours).toBe(12)
+    expect(body.items[0].work_type).toBe('malning')
+    for (const key of [
+      'deduction_type',
+      'labor_hours',
+      'work_type',
+      'housing_designation',
+      'apartment_number',
+      'brf_org_number',
+    ]) {
+      expect(body.items[1]).not.toHaveProperty(key)
+    }
+    // Non-personal fields survive the strip.
+    expect(body.items[1].description).toBe('Konsulttid')
+    expect(body.items[1].accrual_period_start).toBeNull()
+  })
+
+  it('always sends ore_rounding and default_dimensions ({} clears)', () => {
+    const body = JSON.parse(
+      jsonOf(buildInvoiceWritePayload(form(), { oreRounding: false, defaultDims: {} })),
+    )
+    expect(body.ore_rounding).toBe(false)
+    expect(body.default_dimensions).toEqual({})
+  })
+})
+
+describe('pruneItemDimensions', () => {
+  it('turns empty and null bags into undefined (inherit) and keeps valued bags', () => {
+    const [a, b, c] = pruneItemDimensions([
+      plainItem({ dimensions: {} }),
+      plainItem({ dimensions: null }),
+      plainItem({ dimensions: { '1': 'KS01' } }),
+    ])
+    expect(a.dimensions).toBeUndefined()
+    expect(b.dimensions).toBeUndefined()
+    expect(c.dimensions).toEqual({ '1': 'KS01' })
+  })
+})
+
+describe('hasDimensionValues', () => {
+  it('is false for null/undefined/empty and true for a valued bag', () => {
+    expect(hasDimensionValues(null)).toBe(false)
+    expect(hasDimensionValues(undefined)).toBe(false)
+    expect(hasDimensionValues({})).toBe(false)
+    expect(hasDimensionValues({ '6': 'P001' })).toBe(true)
+  })
+})
+
+describe('stripSelfBillingFields / sanitizeDeductionItems', () => {
+  it('stripSelfBillingFields removes exactly the three carriers', () => {
+    const out = stripSelfBillingFields(form()) as Record<string, unknown>
+    expect(out).not.toHaveProperty('external_invoice_number')
+    expect(out).not.toHaveProperty('self_billing_agreement_ref')
+    expect(out).not.toHaveProperty('received_date')
+    expect(out.customer_id).toBe('cust-1')
+    expect(out.items).toHaveLength(1)
+  })
+
+  it('sanitizeDeductionItems leaves deduction lines untouched (same reference)', () => {
+    const rot = rotItem()
+    const out = sanitizeDeductionItems([rot])
+    expect(out[0]).toBe(rot)
+  })
+})
+
+describe('buildSelfBilledPayload parity and semantics', () => {
+  const selfBilledForm = form({
+    external_invoice_number: 'K-2026-17',
+    self_billing_agreement_ref: '',
+    received_date: '2026-08-15',
+    notes: 'Mottagen självfaktura',
+    items: [
+      plainItem({ article_id: 'art-1', revenue_account: '3001', dimensions: { '1': 'KS01' } }),
+      plainItem({ description: 'Frakt', quantity: 1, unit: 'st', unit_price: 120, vat_rate: 25 }),
+    ],
+  })
+
+  it('matches the legacy inline body byte for byte', () => {
+    expect(jsonOf(buildSelfBilledPayload(selfBilledForm))).toBe(
+      jsonOf(legacySelfBilledPayload(selfBilledForm)),
+    )
+  })
+
+  it('reduces items to the five wire fields', () => {
+    const body = JSON.parse(jsonOf(buildSelfBilledPayload(selfBilledForm)))
+    expect(Object.keys(body.items[0]).sort()).toEqual([
+      'description',
+      'quantity',
+      'unit',
+      'unit_price',
+      'vat_rate',
+    ])
+  })
+
+  it("coerces an empty agreement ref to undefined so it drops off the wire", () => {
+    const body = JSON.parse(jsonOf(buildSelfBilledPayload(selfBilledForm)))
+    expect(body).not.toHaveProperty('self_billing_agreement_ref')
+    const withRef = JSON.parse(
+      jsonOf(buildSelfBilledPayload({ ...selfBilledForm, self_billing_agreement_ref: 'AVT-9' })),
+    )
+    expect(withRef.self_billing_agreement_ref).toBe('AVT-9')
+  })
+
+  it('never sends document_type, ROT/RUT or payment-link fields', () => {
+    const body = JSON.parse(jsonOf(buildSelfBilledPayload(selfBilledForm)))
+    for (const key of ['document_type', 'payment_link_url', 'payment_link_auto', 'ore_rounding', 'deduction_personnummer']) {
+      expect(body).not.toHaveProperty(key)
+    }
+  })
+})
@@ -0,0 +1,173 @@
+/**
+ * Pure payload builders for the invoice editor (components/invoices/
+ * InvoiceEditor.tsx). Extracted so the exact request bodies the editor sends
+ * to POST /api/invoices, PATCH /api/invoices/[id] and POST
+ * /api/invoices/self-billed are pinned by unit tests: the repo renders no
+ * components in tests, so these builders are the byte-compatibility ratchet
+ * under any editor re-layout.
+ *
+ * Nothing in here may read component state: every input arrives as an
+ * argument, every function is a pure mapping from form data to wire body.
+ */
+
+/** True when a dimensions bag ({sie_dim_no: code}) carries at least one value. */
+export function hasDimensionValues(
+  dims: Record<string, string> | null | undefined,
+): boolean {
+  return !!dims && Object.keys(dims).length > 0
+}
+
+/** The self-billing carrier fields the form always holds (default ''). */
+export interface SelfBillingCarrierFields {
+  external_invoice_number?: string
+  self_billing_agreement_ref?: string
+  received_date?: string
+}
+
+/** The per-item ROT/RUT fields that are privacy-stripped when unused. */
+export interface DeductionItemFields {
+  deduction_type?: 'rot' | 'rut' | null
+  labor_hours?: number | null
+  work_type?: string | null
+  housing_designation?: string | null
+  apartment_number?: string | null
+  brf_org_number?: string | null
+}
+
+/**
+ * Per-item bags ride the payload only when they carry values: the server
+ * treats an absent bag as "inherit the invoice's default_dimensions".
+ */
+export function pruneItemDimensions<
+  T extends { dimensions?: Record<string, string> | null },
+>(items: T[]): T[] {
+  return items.map((item) =>
+    hasDimensionValues(item.dimensions) ? item : { ...item, dimensions: undefined },
+  )
+}
+
+/**
+ * The form always carries the self-billing fields (they default to '' in both
+ * create and edit mode). The editor's normal create/draft/edit flows never
+ * use self-billing (that goes through /api/invoices/self-billed), so drop the
+ * empty carriers before spreading the form data into the /api/invoices (or
+ * PATCH) body: a bare external_invoice_number: '' otherwise trips the shared
+ * CreateInvoiceSchema's min(1). Belt-and-suspenders; the server schema also
+ * coerces '' to undefined for these fields.
+ */
+export function stripSelfBillingFields<T extends SelfBillingCarrierFields>(
+  data: T,
+): Omit<T, keyof SelfBillingCarrierFields> {
+  const {
+    external_invoice_number: _ein,
+    self_billing_agreement_ref: _sbar,
+    received_date: _rd,
+    ...rest
+  } = data
+  return rest
+}
+
+/**
+ * Privacy by default: ROT/RUT line fields are only sent to the API when the
+ * line actually claims a deduction. Defaults are pre-instantiated as null in
+ * the form state, but null personal-data fields shouldn't ride along on every
+ * regular invoice.
+ */
+export function sanitizeDeductionItems<T extends DeductionItemFields>(
+  items: T[],
+): Array<T | Omit<T, keyof DeductionItemFields>> {
+  return items.map((item) => {
+    if (item.deduction_type) return item
+    const {
+      deduction_type: _dt,
+      labor_hours: _lh,
+      work_type: _wt,
+      housing_designation: _hd,
+      apartment_number: _an,
+      brf_org_number: _bn,
+      ...rest
+    } = item
+    return rest
+  })
+}
+
+export interface InvoiceWritePayloadOptions {
+  /** POST with save_as_draft: true (unnumbered draft, no invoice.created). */
+  saveAsDraft?: boolean
+  /** Öresavrundning display flag (component state, not a form field). */
+  oreRounding: boolean
+  /** Invoice-level default dims: always sent so an edit can clear them ({} = none). */
+  defaultDims: Record<string, string>
+}
+
+/**
+ * The one body builder behind "Granska & skapa" (POST), "Spara som utkast"
+ * (POST + save_as_draft) and edit mode (PATCH). Unifies the three previously
+ * inline, near-identical builders in InvoiceEditor.tsx: same dimension
+ * pruning, same ROT/RUT privacy strip, same invoice-level personnummer /
+ * housing sanitization.
+ */
+export function buildInvoiceWritePayload<
+  TItem extends DeductionItemFields & { dimensions?: Record<string, string> | null },
+  TForm extends SelfBillingCarrierFields & { items: TItem[] },
+>(data: TForm, options: InvoiceWritePayloadOptions) {
+  const anyDeduction = data.items.some((i) => i.deduction_type)
+  const sanitizedItems = sanitizeDeductionItems(pruneItemDimensions(data.items))
+  return {
+    ...stripSelfBillingFields(data),
+    ...(options.saveAsDraft ? { save_as_draft: true } : {}),
+    ore_rounding: options.oreRounding,
+    default_dimensions: options.defaultDims,
+    items: sanitizedItems,
+    // Invoice-level personnummer/housing only ride along when a deduction is
+    // actually claimed somewhere. undefined keys disappear in JSON.
+    ...(anyDeduction
+      ? {}
+      : { deduction_personnummer: undefined, deduction_housing_designation: undefined }),
+  }
+}
+
+/** The reduced field set POST /api/invoices/self-billed accepts. */
+export interface SelfBilledFormShape {
+  customer_id: string
+  external_invoice_number?: string
+  self_billing_agreement_ref?: string
+  invoice_date: string
+  received_date?: string
+  due_date: string
+  currency: string
+  notes?: string
+  items: Array<{
+    description: string
+    quantity: number
+    unit: string
+    unit_price: number
+    vat_rate: number
+  }>
+}
+
+/**
+ * Body mapper for a mottagen självfaktura (POST /api/invoices/self-billed):
+ * a faithful revenue-only transcription, so items are reduced to the five
+ * wire fields and none of the invoice-doc extras (document_type, ROT/RUT,
+ * payment link, ore_rounding) are sent.
+ */
+export function buildSelfBilledPayload<T extends SelfBilledFormShape>(data: T) {
+  return {
+    customer_id: data.customer_id,
+    external_invoice_number: data.external_invoice_number,
+    self_billing_agreement_ref: data.self_billing_agreement_ref || undefined,
+    invoice_date: data.invoice_date,
+    received_date: data.received_date,
+    due_date: data.due_date,
+    currency: data.currency,
+    notes: data.notes,
+    items: data.items.map((i) => ({
+      description: i.description,
+      quantity: i.quantity,
+      unit: i.unit,
+      unit_price: i.unit_price,
+      vat_rate: i.vat_rate,
+    })),
+  }
+}