import { NextResponse } from 'next/server'
import { createDraftEntry, createJournalEntry } from '@/lib/bookkeeping/engine'
import { bookkeepingErrorResponse } from '@/lib/bookkeeping/errors'
import { ensureInitialized } from '@/lib/init'
import { withRouteContext } from '@/lib/api/with-route-context'
import { validateBody } from '@/lib/api/validate'
import { CreateJournalEntrySchema } from '@/lib/api/schemas'
import { escapeLikePattern } from '@/lib/invoices/duplicate-payment-guard'
import { getErrorMessage } from '@/lib/errors/get-error-message'

ensureInitialized()

// Query params are hand-parsed with per-param clamping/regex validation (see
// each param's comment) rather than a Zod schema; response shapes are legacy
// `{ data, count }` / `{ error: string }` for the verifikat list UI.
export const GET = withRouteContext('bookkeeping.journal_entries.list', async (request, ctx) => {
  const { supabase, companyId, log } = ctx

  const { searchParams } = new URL(request.url)
  const periodId = searchParams.get('period_id')
  const status = searchParams.get('status')
  // Drafts get their own surface in the UI; the committed list excludes them.
  const excludeDraft = searchParams.get('exclude_draft') === 'true'
  // Collapse a correction group to the live correction (hide the storno and the
  // reversed original it replaced). The full chain stays reachable.
  const collapseCorrections = searchParams.get('collapse_corrections') === 'true'
  // Clamp pagination to bound DB work against oversized/pathological inputs
  // (compliance A.8.28 / ASVS V1.2.5). The UI page-size selector offers
  // 20/50/100/Alla; "Alla" sends a large limit which is capped at MAX_LIMIT.
  const MAX_LIMIT = 100000
  const rawLimit = parseInt(searchParams.get('limit') || '50', 10)
  const limit = Number.isFinite(rawLimit) ? Math.min(Math.max(rawLimit, 1), MAX_LIMIT) : 50
  const rawOffset = parseInt(searchParams.get('offset') || '0', 10)
  const offset = Number.isFinite(rawOffset) && rawOffset >= 0 ? rawOffset : 0
  const dateFrom = searchParams.get('date_from')
  const dateTo = searchParams.get('date_to')
  const sortDate = searchParams.get('sort_date') // 'asc' | 'desc'
  // 'series' optional filter: single uppercase letter A-Z. Ignored if any
  // other value is passed (defense against trivial injection / typos).
  const seriesRaw = searchParams.get('series')
  const seriesFilter = seriesRaw && /^[A-Z]$/.test(seriesRaw) ? seriesRaw : null
  // Free-text search over the voucher description (verifikationstext). When set,
  // we take the direct-query path below (the include_related RPC can't search),
  // which filters strictly by fiscal_period_id. So search is scoped to the
  // selected fiscal period / company and (like voucher sort) does NOT surface
  // cross-period follow-up entries: every result stays inside the selected
  // year's series (the BFL-compliant per-year view). It narrows the period, it
  // never widens it.
  const search = searchParams.get('search')?.trim() || null
  // 'date_desc' (default) | 'date_asc' | 'voucher_asc' | 'voucher_desc'
  // sort_by overrides sort_date when present. sort_date is kept for backwards
  // compatibility with older clients.
  const sortBy = searchParams.get('sort_by')
  const isVoucherSort = sortBy === 'voucher_asc' || sortBy === 'voucher_desc'
  // Default on: when a fiscal period is selected, include follow-up entries
  // booked in later periods whose source aggregate (invoice, supplier invoice)
  // is dated inside the selected period. Pass include_related=false to
  // restore strict fiscal_period_id filtering.
  const includeRelated = searchParams.get('include_related') !== 'false'

  const dateAscending = sortDate === 'asc' || sortBy === 'date_asc'
  const sortDateParam = sortBy === 'date_asc' || sortDate === 'asc' ? 'asc' : 'desc'

  // Voucher-sort path: include_related RPC doesn't support voucher ordering,
  // so fall through to the direct query below. This means voucher sort is
  // *strict by fiscal_period_id*: cross-period follow-up entries that the
  // RPC normally surfaces under date sort are excluded under voucher sort.
  // That's intentional: voucher numbers are series-scoped within a fiscal
  // year (BFL 5 kap 6-7 §§), so showing series A1, A2 … alongside entries
  // belonging to a different year's series would be misleading. The trade-off
  // is that the visible row count may differ between sort modes for the same
  // period; the strict count is the BFL-compliant view of that year.
  if (periodId && includeRelated && !isVoucherSort && !search) {
    const { data, error } = await supabase.rpc('list_fiscal_period_entries_with_related', {
      p_company_id: companyId,
      p_period_id: periodId,
      p_include_related: true,
      p_status: status,
      p_date_from: dateFrom,
      p_date_to: dateTo,
      p_sort_date: sortDateParam,
      p_limit: limit,
      p_offset: offset,
      p_exclude_draft: excludeDraft,
      p_collapse_corrections: collapseCorrections,
      // Series filter lives in the RPC now (#798): filtering here after the RPC
      // paged would recompute count from one page only, breaking pagination.
      p_series: seriesFilter,
    })

    if (error) {
      log.error('failed to list fiscal period entries via RPC', error)
      return NextResponse.json(
        { error: 'Verifikationerna kunde inte hämtas. Försök igen.' },
        { status: 500 }
      )
    }

    const rows = data ?? []
    const entries = rows.map((r: { entry: unknown }) => r.entry)
    const count = rows.length > 0 ? Number((rows[0] as { total_count: number | string }).total_count) : 0

    return NextResponse.json({ data: entries, count })
  }

  let query = supabase
    .from('journal_entries')
    .select('*, lines:journal_entry_lines(*)', { count: 'exact' })
    .eq('company_id', companyId)

  if (isVoucherSort) {
    const voucherAscending = sortBy === 'voucher_asc'
    query = query
      .order('voucher_series', { ascending: voucherAscending })
      .order('voucher_number', { ascending: voucherAscending })
  } else if (sortDate === 'asc' || sortDate === 'desc' || sortBy === 'date_asc' || sortBy === 'date_desc') {
    // Tiebreak same-date vouchers in the SAME direction as the date sort, and
    // by series before number so the order matches the RPC path (#972).
    query = query
      .order('entry_date', { ascending: dateAscending })
      .order('voucher_series', { ascending: dateAscending })
      .order('voucher_number', { ascending: dateAscending })
  } else {
    query = query
      .order('voucher_series', { ascending: true })
      .order('voucher_number', { ascending: true })
  }

  query = query.range(offset, offset + limit - 1)

  if (periodId) {
    query = query.eq('fiscal_period_id', periodId)
  }

  if (status) {
    query = query.eq('status', status)
  } else {
    query = query.neq('status', 'cancelled')
    if (excludeDraft) {
      query = query.neq('status', 'draft')
    }
  }

  if (dateFrom) {
    query = query.gte('entry_date', dateFrom)
  }

  if (dateTo) {
    query = query.lte('entry_date', dateTo)
  }

  if (seriesFilter) {
    query = query.eq('voucher_series', seriesFilter)
  }

  if (search) {
    // Escape LIKE wildcards (\ % _) so they match literally, and cap the needle
    // length (≤200 chars): both handled by the shared escapeLikePattern helper.
    // The cap bounds DB work against oversized/pathological inputs (compliance
    // A.8.28 / ASVS V1.2.5); escaping prevents silent over-matching on values
    // like "50%". Supabase parameterises the value, so this is not about SQLi.
    query = query.ilike('description', `%${escapeLikePattern(search)}%`)
  }

  // Collapse correction groups (voucher-sort / search path): hide the storno
  // and the reversed originals a posted correction replaced, leaving the live
  // correction. Pagination/count stay correct because these are query filters.
  if (collapseCorrections) {
    query = query.neq('source_type', 'storno')
    const { data: corrections } = await supabase
      .from('journal_entries')
      .select('correction_of_id')
      .eq('company_id', companyId)
      .eq('source_type', 'correction')
      .eq('status', 'posted')
      .not('correction_of_id', 'is', null)
    const correctedOriginalIds = Array.from(
      new Set((corrections ?? []).map((r) => r.correction_of_id).filter(Boolean) as string[])
    )
    if (correctedOriginalIds.length > 0) {
      query = query.not('id', 'in', `(${correctedOriginalIds.join(',')})`)
    }
  }

  const { data, error, count } = await query

  if (error) {
    log.error('failed to list journal entries', error)
    return NextResponse.json(
      { error: 'Verifikationerna kunde inte hämtas. Försök igen.' },
      { status: 500 }
    )
  }

  return NextResponse.json({ data, count })
})

export const POST = withRouteContext(
  'bookkeeping.journal_entries.create',
  async (request, ctx) => {
  const { supabase, companyId, user, log } = ctx

  const validation = await validateBody(request, CreateJournalEntrySchema)
  if (!validation.success) return validation.response
  const body = validation.data

  const { searchParams } = new URL(request.url)
  const asDraft = searchParams.get('as_draft') === 'true'

  try {
    const entry = asDraft
      ? await createDraftEntry(supabase, companyId, user.id, body)
      : await createJournalEntry(supabase, companyId, user.id, body)
    return NextResponse.json({ data: entry })
  } catch (err) {
    const typed = bookkeepingErrorResponse(err)
    if (typed) return typed
    // Untyped errors map to Swedish via getErrorMessage: the raw message is
    // logged here and must never reach the user verbatim (issue #337).
    log.error('failed to create journal entry', err as Error)
    return NextResponse.json(
      { error: getErrorMessage(err, { context: 'journal_entry' }) },
      { status: 400 }
    )
  }
  },
  { requireWrite: true },
)