import { describe, it, expect, beforeAll, vi, afterEach, beforeEach } from 'vitest'
import * as db from '../src/database.js'
import { registerSubscription, CONFIRM_EMAIL_COOLDOWN_SECONDS } from '../src/actions.js'
import * as mailer from '../src/mailer.js'

// Guard: at most one confirmation email per subscription per cooldown window,
// no matter how many PUTs arrive (e.g. a page-refresh storm while unconfirmed).

vi.mock('../src/mailer.js', async (importOriginal) => {
  const actual: any = await importOriginal()
  return { ...actual, sendConfirm: vi.fn(async () => {}) }
})

const unique = (label: string) => `${label}-${Date.now()}-${Math.random().toString(36).slice(2)}`
const pubkey = unique('cooldown')
const email = `${unique('cooldown')}@example.com`

const confirmCalls = () => vi.mocked(mailer.sendConfirm).mock.calls.length

describe('Confirmation email cooldown', () => {
  beforeAll(async () => {
    await db.migrate()
  })

  beforeEach(() => {
    vi.mocked(mailer.sendConfirm).mockClear()
  })

  it('sends a confirmation email on the first register', async () => {
    const res = await registerSubscription({ pubkey, email, frequency: 'daily' })
    expect(res.key).toBeTruthy()
    expect(confirmCalls()).toBe(1)
  })

  it('does NOT re-send a confirmation email on re-register (refresh/retry storm)', async () => {
    // Simulate several PUTs arriving in quick succession (e.g. page reloads).
    for (let i = 0; i < 5; i++) {
      await registerSubscription({ pubkey, email, frequency: 'daily' })
    }
    expect(confirmCalls()).toBe(0)
  })

  it('a new frequency (setting change) does not re-send', async () => {
    await registerSubscription({ pubkey, email, frequency: 'weekly' })
    expect(confirmCalls()).toBe(0)
  })

  it('changing the email address sends immediately (cooldown reset)', async () => {
    const newEmail = `${unique('cooldown')}@example.com`
    await registerSubscription({ pubkey, email: newEmail, frequency: 'daily' })
    expect(confirmCalls()).toBe(1)
  })

  it('a fresh unconfirmed subscription is still throttled after confirm-sent marker', async () => {
    // New pubkey: first PUT sends one email; immediate re-PUT is suppressed.
    const pk2 = unique('cooldown2')
    const em2 = `${unique('cooldown2')}@example.com`
    await registerSubscription({ pubkey: pk2, email: em2, frequency: 'daily' })
    await registerSubscription({ pubkey: pk2, email: em2, frequency: 'daily' })
    expect(confirmCalls()).toBe(1)
  })

  it('cooldown window constant is 10 minutes', () => {
    expect(CONFIRM_EMAIL_COOLDOWN_SECONDS).toBe(600)
  })
})

describe('Cooldown reset on subscription reactivation (same email, off/on cycle)', () => {
  const k = unique('cooldown-reactivate')
  const e = `${unique('cooldown-reactivate')}@example.com`

  beforeAll(async () => {
    await db.migrate()
  })

  beforeEach(() => {
    vi.mocked(mailer.sendConfirm).mockClear()
  })

  it('register, confirm, unsubscribe, re-register same email → fresh key emails immediately', async () => {
    const r1 = await registerSubscription({ pubkey: k, email: e, frequency: 'daily' })
    const active = await db.getSubscriptionByPubkey(k)

    // Confirm first so reactivation is a "keep confirmed" path — but that also
    // means no confirm email on re-register (already confirmed). Verify the row
    // is reactivated with a fresh key, not a duplicate.
    const confirmed = await db.confirmSubscription(active!.key)
    expect(confirmed).toBeTruthy()

    await db.unsubscribeSubscription(active!.key)

    vi.mocked(mailer.sendConfirm).mockClear()
    const r2 = await registerSubscription({ pubkey: k, email: e, frequency: 'daily' })

    expect(r2.key).not.toBe(r1.key) // fresh key issued
    expect(confirmCalls()).toBe(0) // still confirmed → no new email

    const rows = await db.getAllSubscriptionsByPubkey(k)
    expect(rows).toHaveLength(1)
  })
})