fix(invoices): bank match stores the applied amount, not cash received, in invoice_payments (#2277)

* fix(invoices): bank match stores the applied amount, not cash received, in invoice_payments

The dashboard match-invoice route, its v1 twin and the pending-operation
match_transaction_invoice executor wrote invoice_payments.amount as the
cash received in invoice currency. When a whole-krona bank line settles an
öre-carrying remaining (the customer pays the rounded "Att betala"),
planInvoicePayment advances paid_amount by the remaining only and books
the öre on 3740, so the row exceeded the receivable by the absorbed öre:
remaining 999.60, bank 1 000.00 gave a 1 000.00 row against a 999.60
paid_amount. The kontantmetod cut-off then pushed a -0.40 receivable with
negative scaled moms, the historical AR ledger showed -0.40 outstanding
on a paid invoice, and a storno of the payment voucher restored
paid_amount 0.40 off (issue #2250).

PR #2236 defined the amount for the manual, MCP and Stripe paths as the
amount APPLIED to the invoice (new paid_amount minus the prior one). The
three bank-match paths now share that definition through one helper,
appliedPaymentAmount() in lib/invoices/invoice-payment-row.ts, which
recordInvoicePaymentRow() uses as well. Every other field of the row
(payment date, currency, exchange rate, journal entry, bank transaction,
notes) is unchanged. Without a residual the applied amount equals the
cash received, so ordinary matches post identical rows; cross-currency
rows are now öre-rounded like paid_amount instead of the 4-decimal spot
conversion, so row and paid_amount agree.

Existing rows carrying the overshoot are not repaired here; that is a
separate call.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015qgLgdt4mLmha1ZLFMwq1u

* refactor(invoices): one writer for invoice_payments rows

Rework of the #2250 fix from first principles. The bank-match paths did
not just get the amount wrong; the class of bug is that invoice_payments
rows were hand-built at five product sites (dashboard bank match, its v1
twin, the pending-operation match, the link-to-existing-voucher flow, and
the #2236 paths through the helper), each computing its own fields with
no single definition of what the row means.

recordInvoicePaymentRow() (lib/invoices/invoice-payment-row.ts) is now the
one writer. Its options grew by what the bank paths set, all optional with
today's defaults so the #2236 callers are unchanged: transactionId
(default null), exchangeRate (the rate actually used; omitted =
invoice.exchange_rate, explicit null stored as null) and notes (default
null). The failure result carries the Postgres SQLSTATE so the routes keep
mapping a unique violation (23505) exactly as before. The applied-amount
formula is an internal detail of that file again.

Routed through the writer: app/api/transactions/[id]/match-invoice, the
v1 match-invoice twin, commitMatchTransactionInvoice in
lib/pending-operations/commit.ts, and lib/transactions/link-journal-entry.ts
(strict plan, same currency only: its amount is unchanged, it now shares
the row semantics). The pending-operation path used to drop the insert
error on the floor; it stays non-fatal but is logged with ids.

Guard: scripts/checks/no-new-antipatterns.mjs gains
direct-invoice-payment-insert, a file-set rule with no baseline (0 today):
.from('invoice_payments').insert( or .upsert( anywhere under app/, lib/ or
extensions/ outside lib/invoices/invoice-payment-row.ts fails
npm run check:guards. Operator scripts under scripts/ are out of its scope
on purpose.

Tests: the writer's unit tests cover the new options, the explicit-null
rate, the SQLSTATE passthrough and the öre-rounded prior-paid
subtraction; the per-path 3740 tests from the first commit stand; mock
insert slots now return the row id the writer selects back.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015qgLgdt4mLmha1ZLFMwq1u

---------

Co-authored-by: Jakob Wennberg <311770904+jakobwennberg-oss@users.noreply.github.com>
Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

lib/pending-operations/__tests__/link-transaction-journal-entry.test.ts

@@ -231,7 +231,7 @@ describe('commitPendingOperation: link_transaction_journal_entry', () => {
     })
     enqueue({ data: [{ id: TX_UUID }], error: null }) // tx UPDATE
     enqueue({ data: [{ id: INV_UUID }], error: null }) // optimistic-lock invoice UPDATE
-    enqueue({ data: null, error: null }) // invoice_payments INSERT
+    enqueue({ data: { id: 'ip-1' }, error: null }) // invoice_payments INSERT
     enqueue({ data: null, error: null }) // logMatchEvent insert
     enqueue({ data: null, error: null }) // dispatcher commit update
 

lib/pending-operations/__tests__/match-transaction-invoice-settlement-account.test.ts

@@ -171,7 +171,7 @@ describe('commitPendingOperation: match_transaction_invoice settlement account r
     enqueue({ data: { accounting_method: 'accrual', entity_type: 'aktiebolag' }, error: null }) // settings
     enqueue({ data: { ledger_account: '1940' }, error: null }) // cash_accounts lookup
     enqueue({ data: [{ id: 'inv-1' }], error: null }) // invoice CAS update
-    enqueue({ data: null, error: null }) // invoice_payments insert
+    enqueue({ data: { id: 'ip-1' }, error: null }) // invoice_payments insert
     enqueue({ data: null, error: null }) // transactions update (link)
     enqueue({ data: null, error: null }) // dispatcher pending_operations update
 
@@ -196,6 +196,15 @@ describe('commitPendingOperation: match_transaction_invoice settlement account r
     expect(mockCreateCashEntry).not.toHaveBeenCalled()
     const invoiceUpdate = findCalls('invoices', 'update').at(-1)?.[0]
     expect(invoiceUpdate).toMatchObject({ paid_at: '2026-05-12T12:00:00Z' })
+    // No residual: the applied amount IS the cash received (#2250).
+    expect(findCalls('invoice_payments', 'insert').at(-1)?.[0]).toMatchObject({
+      invoice_id: 'inv-1',
+      transaction_id: 'tx-1',
+      payment_date: '2026-05-12',
+      amount: 12500,
+      currency: 'SEK',
+      journal_entry_id: 'je-1',
+    })
     expect(matchedHandler).toHaveBeenCalledWith(
       expect.objectContaining({
         invoice: expect.objectContaining({
@@ -253,7 +262,7 @@ describe('commitPendingOperation: match_transaction_invoice settlement account r
     enqueue({ data: { accounting_method: 'accrual', entity_type: 'aktiebolag' }, error: null }) // settings
     enqueue({ data: [], error: null }) // resolveSettlementAccount: no enabled cash accounts -> 1930
     enqueue({ data: [{ id: 'inv-1' }], error: null }) // invoice CAS update
-    enqueue({ data: null, error: null }) // invoice_payments insert
+    enqueue({ data: { id: 'ip-1' }, error: null }) // invoice_payments insert
     enqueue({ data: null, error: null }) // transactions update (link)
     enqueue({ data: null, error: null }) // dispatcher pending_operations update
 
@@ -302,7 +311,7 @@ describe('commitPendingOperation: match_transaction_invoice settlement account r
     // it keeps the 1930 fallback.
     enqueue({ data: [], error: null }) // resolveSettlementAccount: no enabled cash accounts
     enqueue({ data: [{ id: 'inv-1' }], error: null }) // invoice CAS update
-    enqueue({ data: null, error: null }) // invoice_payments insert
+    enqueue({ data: { id: 'ip-1' }, error: null }) // invoice_payments insert
     enqueue({ data: null, error: null }) // transactions update (link)
     enqueue({ data: null, error: null }) // dispatcher pending_operations update
 
@@ -407,7 +416,7 @@ describe('commitPendingOperation: match_transaction_invoice settlement account r
     enqueue({ data: { accounting_method: 'accrual', entity_type: 'aktiebolag' }, error: null }) // settings
     enqueue({ data: [], error: null }) // resolveSettlementAccount: no enabled cash accounts -> 1930
     enqueue({ data: [{ id: 'inv-1' }], error: null }) // invoice CAS update
-    enqueue({ data: null, error: null }) // invoice_payments insert
+    enqueue({ data: { id: 'ip-1' }, error: null }) // invoice_payments insert
     enqueue({ data: null, error: null }) // transactions update (link)
     enqueue({ data: null, error: null }) // dispatcher pending_operations update
 
@@ -435,6 +444,79 @@ describe('commitPendingOperation: match_transaction_invoice settlement account r
     })
   })
 
+  it('3740 residual: the invoice_payments row carries the applied amount, not the cash received (#2250)', async () => {
+    // Remaining 999.60 settled by a whole-krona 1 000.00 bank line: 3740
+    // absorbs the 0.40 and paid_amount advances by the remaining only, so the
+    // AR sub-ledger row must be 999.60 as well (parity with the dashboard and
+    // v1 routes; the #2236 definition every reader relies on).
+    const { supabase, enqueue, findCalls } = createQueuedMockSupabase()
+    enqueue({ data: { id: 'op-1' }, error: null }) // CAS claim
+    enqueue({
+      data: {
+        id: 'tx-1',
+        company_id: 'company-1',
+        amount: 1000,
+        currency: 'SEK',
+        date: '2026-05-12',
+        invoice_id: null,
+        journal_entry_id: null,
+        cash_account_id: null,
+      },
+      error: null,
+    }) // transaction fetch
+    enqueue({
+      data: {
+        id: 'inv-1',
+        invoice_number: 'F-2026002',
+        status: 'sent',
+        total: 999.6,
+        remaining_amount: 999.6,
+        paid_amount: 0,
+        currency: 'SEK',
+        exchange_rate: null,
+        journal_entry_id: null,
+        customer: { name: 'Test AB' },
+      },
+      error: null,
+    }) // invoice fetch
+    enqueue({ data: { accounting_method: 'accrual', entity_type: 'aktiebolag' }, error: null }) // settings
+    enqueue({ data: [], error: null }) // resolveSettlementAccount: no enabled cash accounts -> 1930
+    enqueue({ data: [{ id: 'inv-1' }], error: null }) // invoice CAS update
+    enqueue({ data: { id: 'ip-1' }, error: null }) // invoice_payments insert
+    enqueue({ data: null, error: null }) // transactions update (link)
+    enqueue({ data: null, error: null }) // dispatcher pending_operations update
+
+    const op = makePendingOp({ params: { transaction_id: 'tx-1', invoice_id: 'inv-1' } })
+    const result = await commitPendingOperation(supabase as never, 'user-1', 'company-1', op)
+
+    expect(result.status).toBe('committed')
+    expect(mockCreateJournalEntry).toHaveBeenCalledWith(
+      expect.anything(),
+      'company-1',
+      'user-1',
+      expect.objectContaining({
+        lines: expect.arrayContaining([
+          expect.objectContaining({ account_number: '1930', debit_amount: 1000 }),
+          expect.objectContaining({ account_number: '1510', credit_amount: 999.6 }),
+          expect.objectContaining({ account_number: '3740', credit_amount: 0.4 }),
+        ]),
+      }),
+    )
+    expect(findCalls('invoices', 'update').at(-1)?.[0]).toMatchObject({
+      status: 'paid',
+      paid_amount: 999.6,
+      remaining_amount: 0,
+    })
+    expect(findCalls('invoice_payments', 'insert').at(-1)?.[0]).toMatchObject({
+      invoice_id: 'inv-1',
+      transaction_id: 'tx-1',
+      payment_date: '2026-05-12',
+      amount: 999.6,
+      currency: 'SEK',
+      journal_entry_id: 'je-1',
+    })
+  })
+
   it('converts a cross-currency payment into the invoice currency before recording it', async () => {
     // Parity with the dashboard/v1 routes: feeding the raw SEK amount into a
     // USD invoice corrupts the units of paid_amount / remaining_amount and
@@ -474,7 +556,7 @@ describe('commitPendingOperation: match_transaction_invoice settlement account r
     enqueue({ data: { accounting_method: 'accrual', entity_type: 'aktiebolag' }, error: null }) // settings
     enqueue({ data: [], error: null }) // resolveSettlementAccount: no enabled cash accounts -> 1930
     enqueue({ data: [{ id: 'inv-1' }], error: null }) // invoice CAS update
-    enqueue({ data: null, error: null }) // invoice_payments insert
+    enqueue({ data: { id: 'ip-1' }, error: null }) // invoice_payments insert
     enqueue({ data: null, error: null }) // transactions update (link)
     enqueue({ data: null, error: null }) // dispatcher pending_operations update
 

lib/pending-operations/commit.ts

@@ -3504,18 +3504,35 @@ async function commitMatchTransactionInvoice(
   // No cash-method note here anymore: pure kontantmetoden partials are now
   // rejected above, and for an invoice booked at send the clearing entry
   // handles a partial correctly, so the note would be misleading.
-  await supabase.from('invoice_payments').insert({
-    user_id: userId,
-    company_id: companyId,
-    invoice_id: invoiceId,
-    payment_date: transaction.date,
-    amount: paidAmount,
-    currency: invoice.currency,
-    exchange_rate: fx.required ? fx.rate : invoice.exchange_rate,
-    journal_entry_id: journalEntryId,
-    transaction_id: transactionId,
-    notes: null,
+  // The AR sub-ledger row goes through the single writer
+  // (lib/invoices/invoice-payment-row.ts), which owns the amount definition:
+  // applied to the invoice, never the cash received (#2250). Not fatal here,
+  // exactly like the fire-and-forget insert it replaces: the voucher and the
+  // invoice update are already committed. The failure is logged now, so the
+  // row the kontantmetod cut-off would otherwise miss can be added.
+  const recorded = await recordInvoicePaymentRow(supabase, {
+    userId,
+    companyId,
+    invoice: {
+      id: invoiceId,
+      currency: invoice.currency,
+      exchange_rate: invoice.exchange_rate,
+      paid_amount: invoice.paid_amount,
+    },
+    paymentDate: transaction.date,
+    newPaidAmount,
+    journalEntryId,
+    transactionId,
+    exchangeRate: fx.required ? fx.rate : invoice.exchange_rate,
   })
+  if (!recorded.ok) {
+    log.error('match_transaction_invoice: invoice_payments insert failed', undefined, {
+      invoiceId,
+      transactionId,
+      companyId,
+      error: recorded.error,
+    })
+  }
 
   // The invoice is now settled, so every OTHER transaction still carrying a
   // suggestion pointer at it is dead: retire them (issue #1259). This