// apps/hq/test/reminder-preview.test.ts
import { describe, it, expect, beforeAll, afterAll } from 'vitest'
import express from 'express'
import { openDb } from '../src/db'
import { seedIfEmpty } from '../src/seed'
import { createStaff } from '../src/auth'
import { createClient } from '../src/repos-clients'
import { createModule, setPrice } from '../src/repos-modules'
import { createDraft, issueDocument } from '../src/repos-documents'
import { upsertReminder } from '../src/repos-reminders'
import { apiRouter } from '../src/api'

async function appWith() {
  const db = openDb(':memory:'); await seedIfEmpty(db) // company.name='Tecnostac'
  await createStaff(db, { email: 'owner@test.in', displayName: 'Owner', role: 'owner', password: 'owner-password' })
  const c = await createClient(db, 'u1', { name: 'Acme', code: 'ACME', stateCode: '32', contacts: [{ name: 'Ravi', email: 'ravi@acme.in' }] })
  const m = await createModule(db, 'u1', { code: 'POS', name: 'POS' })
  await setPrice(db, 'u1', { moduleId: m.id, kind: 'yearly', pricePaise: 10_000_00, effectiveFrom: '2026-04-01' })
  const inv = await issueDocument(db, 'u1', (await createDraft(db, 'u1', { docType: 'INVOICE', clientId: c.id, lines: [{ moduleId: m.id, qty: 1, kind: 'yearly' }] })).id)
  const overdue = await upsertReminder(db, { ruleKind: 'invoice_overdue', subjectId: inv.id, duePeriod: '2026-07', clientId: c.id, docId: inv.id })
  const internal = await upsertReminder(db, { ruleKind: 'follow_up', subjectId: 'i1', duePeriod: '2026-07-08', clientId: c.id })
  const app = express(); app.use(express.json()); app.locals['db'] = db; app.use('/api', apiRouter(db))
  const server = app.listen(0)
  const base = `http://localhost:${(server.address() as { port: number }).port}/api`
  return { server, base, inv, overdueId: overdue.id, internalId: internal.id }
}

describe('GET /reminders/:id/preview', () => {
  let ctx: Awaited<ReturnType<typeof appWith>>
  beforeAll(async () => { ctx = await appWith() })
  afterAll(() => ctx.server.close())
  const login = async () =>
    (await (await fetch(`${ctx.base}/auth/login`, { method: 'POST', headers: { 'content-type': 'application/json' }, body: JSON.stringify({ email: 'owner@test.in', password: 'owner-password' }) })).json() as any).token
  const get = async (token: string | null, id: string) => {
    const res = await fetch(`${ctx.base}/reminders/${id}/preview`, { headers: token ? { authorization: `Bearer ${token}` } : {} })
    return { status: res.status, json: await res.json() as any }
  }
  it('requires auth', async () => { expect((await get(null, ctx.overdueId)).status).toBe(401) })
  it('previews the overdue email — subject + body match what would be sent', async () => {
    const token = await login()
    const r = await get(token, ctx.overdueId)
    expect(r.status).toBe(200)
    expect(r.json.subject).toContain(ctx.inv.docNo)  // 'Payment reminder — Invoice INV/26-27-0001 (Tecnostac)'
    expect(r.json.subject).toContain('Tecnostac')
    expect(r.json.body).toContain('Acme')            // clientName
  })
  it('404s an unknown reminder and 400s an internal follow_up', async () => {
    const token = await login()
    expect((await get(token, 'nope')).status).toBe(404)
    expect((await get(token, ctx.internalId)).status).toBe(400)
  })
})