feat(WHE-22): ingest configured topic messages with idempotent persistence

apps/bot/src/purchase-topic-ingestion.test.ts

@@ -0,0 +1,53 @@
+import { describe, expect, test } from 'bun:test'
+
+import {
+  extractPurchaseTopicCandidate,
+  type PurchaseTopicCandidate
+} from './purchase-topic-ingestion'
+
+const config = {
+  householdId: '11111111-1111-4111-8111-111111111111',
+  householdChatId: '-10012345',
+  purchaseTopicId: 777
+}
+
+function candidate(overrides: Partial<PurchaseTopicCandidate> = {}): PurchaseTopicCandidate {
+  return {
+    updateId: 1,
+    chatId: '-10012345',
+    messageId: '10',
+    threadId: '777',
+    senderTelegramUserId: '10002',
+    rawText: 'Bought toilet paper 30 gel',
+    messageSentAt: new Date('2026-03-05T00:00:00.000Z'),
+    ...overrides
+  }
+}
+
+describe('extractPurchaseTopicCandidate', () => {
+  test('returns record when message belongs to configured topic', () => {
+    const record = extractPurchaseTopicCandidate(candidate(), config)
+
+    expect(record).not.toBeNull()
+    expect(record?.householdId).toBe(config.householdId)
+    expect(record?.rawText).toBe('Bought toilet paper 30 gel')
+  })
+
+  test('skips message from other chat', () => {
+    const record = extractPurchaseTopicCandidate(candidate({ chatId: '-10099999' }), config)
+
+    expect(record).toBeNull()
+  })
+
+  test('skips message from other topic', () => {
+    const record = extractPurchaseTopicCandidate(candidate({ threadId: '778' }), config)
+
+    expect(record).toBeNull()
+  })
+
+  test('skips blank text after trim', () => {
+    const record = extractPurchaseTopicCandidate(candidate({ rawText: '   ' }), config)
+
+    expect(record).toBeNull()
+  })
+})