import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest'
import { randomUUID } from 'node:crypto'
import bcrypt from 'bcrypt'

const { requestOtp, verifyOtp, OtpError } = await import('../../src/services/otp.service.js')
const {
  addTestOtpBypassEntry,
  setTestOtpBypassEnabled,
  getTestOtpBypass,
} = await import('../../src/services/config.service.js')
const { db, resetDb } = await import('../helpers/db.js')

// Unique phone per test so rate-limit (3 per hour per phone) doesn't poison
// tests that reuse otp_requests rows. resetDb() truncates otp_requests but
// keeps the rate-limit guarantee tight regardless.
const uniquePhone = () => {
  const digits = randomUUID().replace(/[^0-9]/g, '').slice(0, 10).padEnd(10, '0')
  return `+628${digits}`
}

const clearBypassConfig = async () => {
  const sql = db()
  await sql`DELETE FROM app_config WHERE key = 'test_otp_bypass'`
}

const peekOtpRow = async (id) => {
  const sql = db()
  const [row] = await sql`
    SELECT id, phone, fazpass_reference, is_bypass, code_hash, used_at, expires_at
    FROM otp_requests WHERE id = ${id}
  `
  return row
}

describe('otp.service — hash-at-rest (stub mode)', () => {
  beforeEach(async () => {
    await resetDb()
    await clearBypassConfig()
  })

  it('stores bcrypt(code_hash) instead of plaintext after requestOtp', async () => {
    const phone = uniquePhone()
    const { otp_request_id } = await requestOtp({
      phone, userType: 'customer', ipAddress: '10.0.0.1',
    })
    const row = await peekOtpRow(otp_request_id)

    expect(row).toBeDefined()
    expect(row.is_bypass).toBe(false)
    expect(row.code_hash).toMatch(/^\$2[aby]\$/)        // bcrypt signature
    // fazpass_reference holds ONLY the stub reference now — no ":code" suffix.
    expect(row.fazpass_reference).toMatch(/^stub_/)
    expect(row.fazpass_reference).not.toContain(':')
  })

  it('verifyOtp succeeds against the same plaintext code (via stub peek)', async () => {
    const phone = uniquePhone()
    // Pin the stub to a known code so we don't depend on the in-memory Map.
    vi.stubEnv('OTP_STATIC_CODE', '424242')
    const { otp_request_id } = await requestOtp({
      phone, userType: 'customer', ipAddress: '10.0.0.1',
    })
    const result = await verifyOtp({ otpRequestId: otp_request_id, code: '424242' })
    expect(result).toEqual({ phone, user_type: 'customer' })

    const used = await peekOtpRow(otp_request_id)
    expect(used.used_at).not.toBeNull()
    vi.unstubAllEnvs()
  })

  it('verifyOtp rejects a wrong code with CODE_MISMATCH', async () => {
    const phone = uniquePhone()
    vi.stubEnv('OTP_STATIC_CODE', '111111')
    const { otp_request_id } = await requestOtp({
      phone, userType: 'customer', ipAddress: '10.0.0.1',
    })
    await expect(verifyOtp({ otpRequestId: otp_request_id, code: '999999' }))
      .rejects.toMatchObject({ code: 'CODE_MISMATCH', statusCode: 401 })
    vi.unstubAllEnvs()
  })
})

describe('otp.service — DB-level CHECK constraint', () => {
  beforeEach(async () => {
    await resetDb()
    await clearBypassConfig()
  })

  it('rejects an insert with is_bypass=true and code_hash NULL', async () => {
    const sql = db()
    await expect(sql`
      INSERT INTO otp_requests (phone, user_type, channel, expires_at, is_bypass, code_hash)
      VALUES ('+628999999991', 'customer', 'whatsapp', NOW() + INTERVAL '5 min', true, NULL)
    `).rejects.toMatchObject({ code: '23514' })   // PG check_violation
  })

  it('rejects an insert with is_bypass=true and fazpass_reference set', async () => {
    const sql = db()
    await expect(sql`
      INSERT INTO otp_requests (phone, user_type, channel, expires_at,
                                is_bypass, code_hash, fazpass_reference)
      VALUES ('+628999999992', 'customer', 'whatsapp', NOW() + INTERVAL '5 min',
              true, '$2b$10$abcdefghijklmnopqrstuv', 'leak_ref')
    `).rejects.toMatchObject({ code: '23514' })
  })

  it('allows is_bypass=false with code_hash NULL (Fazpass-live shape) at insert time', async () => {
    const sql = db()
    const [row] = await sql`
      INSERT INTO otp_requests (phone, user_type, channel, expires_at,
                                is_bypass, code_hash, fazpass_reference)
      VALUES ('+628999999993', 'customer', 'whatsapp', NOW() + INTERVAL '5 min',
              false, NULL, 'fazpass_ref_xyz')
      RETURNING id
    `
    expect(row.id).toBeDefined()
  })
})

describe('otp.service — verify anomaly refusal', () => {
  beforeEach(async () => {
    await resetDb()
    await clearBypassConfig()
  })

  it('rejects verify on a row missing BOTH code_hash and fazpass_reference (unverifiable)', async () => {
    const sql = db()
    const [row] = await sql`
      INSERT INTO otp_requests (phone, user_type, channel, expires_at,
                                is_bypass, code_hash, fazpass_reference)
      VALUES ('+628999999994', 'customer', 'whatsapp', NOW() + INTERVAL '5 min',
              false, NULL, NULL)
      RETURNING id
    `
    await expect(verifyOtp({ otpRequestId: row.id, code: '123456' }))
      .rejects.toMatchObject({ code: 'OTP_CORRUPT', statusCode: 500 })
  })

  it('returns OTP_PROVIDER_FAILED when row has fazpass_reference but Fazpass is disabled', async () => {
    const sql = db()
    const [row] = await sql`
      INSERT INTO otp_requests (phone, user_type, channel, expires_at,
                                is_bypass, code_hash, fazpass_reference)
      VALUES ('+628999999998', 'customer', 'whatsapp', NOW() + INTERVAL '5 min',
              false, NULL, 'fazpass_ref_xyz')
      RETURNING id
    `
    // FAZPASS_ENABLED is unset/false in tests; fazpassVerifyOtp throws
    // FazpassError, which otp.service.js converts to OTP_PROVIDER_FAILED 502.
    await expect(verifyOtp({ otpRequestId: row.id, code: '123456' }))
      .rejects.toMatchObject({ code: 'OTP_PROVIDER_FAILED', statusCode: 502 })
  })
})

describe('otp.service — test OTP bypass allowlist', () => {
  beforeEach(async () => {
    await resetDb()
    await clearBypassConfig()
  })
  afterEach(async () => {
    await clearBypassConfig()
  })

  it('plants a bypass row that verifies against the configured static OTP', async () => {
    const phone = uniquePhone()
    await setTestOtpBypassEnabled(true)
    await addTestOtpBypassEntry({
      phone, otp: '294857', user_type: 'customer', label: 'Apple Reviewer #1',
      expires_at: new Date(Date.now() + 24 * 60 * 60 * 1000).toISOString(),
    })

    const { otp_request_id } = await requestOtp({
      phone, userType: 'customer', ipAddress: '10.0.0.2',
    })

    const row = await peekOtpRow(otp_request_id)
    expect(row.is_bypass).toBe(true)
    expect(row.fazpass_reference).toBeNull()
    expect(row.code_hash).toMatch(/^\$2[aby]\$/)

    // Verify against the configured static OTP succeeds.
    const result = await verifyOtp({ otpRequestId: otp_request_id, code: '294857' })
    expect(result).toEqual({ phone, user_type: 'customer' })
  })

  it('does not match when user_type differs (same phone for customer + mitra is distinct)', async () => {
    const phone = uniquePhone()
    await setTestOtpBypassEnabled(true)
    await addTestOtpBypassEntry({
      phone, otp: '111111', user_type: 'mitra', label: 'Internal QA Mitra',
      expires_at: new Date(Date.now() + 24 * 60 * 60 * 1000).toISOString(),
    })

    // Customer request to the same phone → falls through to stub.
    const { otp_request_id } = await requestOtp({
      phone, userType: 'customer', ipAddress: '10.0.0.3',
    })
    const row = await peekOtpRow(otp_request_id)
    expect(row.is_bypass).toBe(false)
    expect(row.fazpass_reference).toMatch(/^stub_/)
  })

  it('does not match when the entry has expired', async () => {
    const phone = uniquePhone()
    await setTestOtpBypassEnabled(true)
    // addTestOtpBypassEntry refuses past dates, so set a valid future date,
    // then manually backdate the entry via SQL — emulating "this entry has
    // been sitting in the list for too long".
    await addTestOtpBypassEntry({
      phone, otp: '222222', user_type: 'customer', label: 'Old Reviewer',
      expires_at: new Date(Date.now() + 60_000).toISOString(),
    })
    const sql = db()
    await sql`
      UPDATE app_config
      SET value = jsonb_set(
        value,
        '{entries,0,expires_at}',
        to_jsonb(${new Date(Date.now() - 60_000).toISOString()}::text)
      )
      WHERE key = 'test_otp_bypass'
    `

    const { otp_request_id } = await requestOtp({
      phone, userType: 'customer', ipAddress: '10.0.0.4',
    })
    const row = await peekOtpRow(otp_request_id)
    expect(row.is_bypass).toBe(false)
  })

  it('does not match when the global kill switch is off', async () => {
    const phone = uniquePhone()
    await setTestOtpBypassEnabled(true)
    await addTestOtpBypassEntry({
      phone, otp: '333333', user_type: 'customer', label: 'Disabled later',
      expires_at: new Date(Date.now() + 24 * 60 * 60 * 1000).toISOString(),
    })
    // Flip the kill switch off — entries remain but no longer match.
    await setTestOtpBypassEnabled(false)

    const { otp_request_id } = await requestOtp({
      phone, userType: 'customer', ipAddress: '10.0.0.5',
    })
    const row = await peekOtpRow(otp_request_id)
    expect(row.is_bypass).toBe(false)
  })

  it('rejects an entry whose plaintext OTP is malformed', async () => {
    await expect(addTestOtpBypassEntry({
      phone: '+628999999995', otp: 'abc', user_type: 'customer', label: 'Bad OTP',
      expires_at: new Date(Date.now() + 24 * 60 * 60 * 1000).toISOString(),
    })).rejects.toMatchObject({ code: 'VALIDATION_ERROR' })
  })

  it('rejects an entry whose expires_at is in the past', async () => {
    await expect(addTestOtpBypassEntry({
      phone: '+628999999996', otp: '123456', user_type: 'customer', label: 'Stale',
      expires_at: new Date(Date.now() - 60_000).toISOString(),
    })).rejects.toMatchObject({ code: 'VALIDATION_ERROR' })
  })

  it('rejects a duplicate (phone, user_type) entry', async () => {
    const phone = uniquePhone()
    const future = new Date(Date.now() + 24 * 60 * 60 * 1000).toISOString()
    await addTestOtpBypassEntry({
      phone, otp: '101010', user_type: 'customer', label: 'First',
      expires_at: future,
    })
    await expect(addTestOtpBypassEntry({
      phone, otp: '202020', user_type: 'customer', label: 'Second',
      expires_at: future,
    })).rejects.toMatchObject({ code: 'DUPLICATE_ENTRY' })
  })

  // No new tests in this describe — see "Fazpass-live mode" below for the
  // request/verify integration coverage.

  it('getTestOtpBypass returns the bcrypt hash, not the plaintext OTP', async () => {
    const phone = uniquePhone()
    await addTestOtpBypassEntry({
      phone, otp: '424242', user_type: 'customer', label: 'Apple #1',
      expires_at: new Date(Date.now() + 24 * 60 * 60 * 1000).toISOString(),
    })
    const list = await getTestOtpBypass()
    expect(list.entries).toHaveLength(1)
    const entry = list.entries[0]
    expect(entry.otp_hash).toMatch(/^\$2[aby]\$/)
    // Defense-in-depth: serialised object must not contain the plaintext anywhere.
    expect(JSON.stringify(entry)).not.toContain('424242')
    // And the hash actually matches the plaintext (so verify works downstream).
    expect(await bcrypt.compare('424242', entry.otp_hash)).toBe(true)
  })
})

describe('otp.service — Fazpass-live mode (FAZPASS_ENABLED=true)', () => {
  const setFazpassEnv = () => {
    vi.stubEnv('FAZPASS_ENABLED', 'true')
    vi.stubEnv('FAZPASS_BASE_URL', 'https://api.fazpass.example')
    vi.stubEnv('FAZPASS_MERCHANT_KEY', 'mkey')
    vi.stubEnv('FAZPASS_GATEWAY_KEY', 'gkey')
    vi.stubEnv('FAZPASS_TIMEOUT_MS', '5000')
  }

  const mockFetch = (impl) => vi.spyOn(globalThis, 'fetch').mockImplementation(impl)
  const jsonResponse = (status, body) => new Response(JSON.stringify(body), {
    status, headers: { 'Content-Type': 'application/json' },
  })

  beforeEach(async () => {
    setFazpassEnv()
    await resetDb()
    await clearBypassConfig()
  })
  afterEach(() => {
    vi.restoreAllMocks()
    vi.unstubAllEnvs()
  })

  it('requestOtp stores fazpass_reference + leaves code_hash NULL when Fazpass returns success', async () => {
    mockFetch(async () => jsonResponse(200, {
      status: true,
      data: {
        id: 'fzp-ref-001', otp: 'XXXXXX', otp_length: 6,
        channel: 'WA_GENERIC_OTP', provider: 'Fazpass', purpose: 'production',
      },
    }))

    const phone = uniquePhone()
    const { otp_request_id, channel_used } = await requestOtp({
      phone, userType: 'customer', ipAddress: '10.0.0.10', channel: 'whatsapp',
    })

    expect(channel_used).toBe('whatsapp')  // API contract: echoes client-requested channel

    const row = await peekOtpRow(otp_request_id)
    expect(row.is_bypass).toBe(false)
    expect(row.fazpass_reference).toBe('fzp-ref-001')
    expect(row.code_hash).toBeNull()
  })

  it('requestOtp propagates Fazpass error and does NOT insert a row', async () => {
    mockFetch(async () => jsonResponse(503, { status: false, code: '5030503', message: 'gateway unavailable' }))

    const phone = uniquePhone()
    await expect(requestOtp({
      phone, userType: 'customer', ipAddress: '10.0.0.11', channel: 'whatsapp',
    })).rejects.toMatchObject({ code: 'OTP_PROVIDER_FAILED', statusCode: 502 })

    const sql = db()
    const [{ n }] = await sql`SELECT COUNT(*)::int AS n FROM otp_requests WHERE phone = ${phone}`
    expect(n).toBe(0)
  })

  it('verifyOtp delegates to Fazpass and succeeds on status:true', async () => {
    // Sequence: 1st fetch = /request, 2nd fetch = /verify.
    let call = 0
    mockFetch(async (url) => {
      call++
      if (url.endsWith('/v1/otp/request')) {
        return jsonResponse(200, { status: true, data: { id: 'fzp-ref-002' } })
      }
      if (url.endsWith('/v1/otp/verify')) {
        return jsonResponse(200, { status: true, code: '2000200' })
      }
      throw new Error(`unexpected url ${url}`)
    })

    const phone = uniquePhone()
    const { otp_request_id } = await requestOtp({
      phone, userType: 'customer', ipAddress: '10.0.0.12', channel: 'whatsapp',
    })
    const result = await verifyOtp({ otpRequestId: otp_request_id, code: '424242' })

    expect(result).toEqual({ phone, user_type: 'customer' })
    expect(call).toBe(2)
    const used = await peekOtpRow(otp_request_id)
    expect(used.used_at).not.toBeNull()
  })

  it('verifyOtp surfaces wrong OTP as CODE_MISMATCH when Fazpass returns status:false', async () => {
    mockFetch(async (url) => {
      if (url.endsWith('/v1/otp/request')) {
        return jsonResponse(200, { status: true, data: { id: 'fzp-ref-003' } })
      }
      return jsonResponse(200, { status: false, code: '4000401', message: 'Invalid OTP' })
    })

    const phone = uniquePhone()
    const { otp_request_id } = await requestOtp({
      phone, userType: 'customer', ipAddress: '10.0.0.13', channel: 'whatsapp',
    })
    await expect(verifyOtp({ otpRequestId: otp_request_id, code: '000000' }))
      .rejects.toMatchObject({ code: 'CODE_MISMATCH', statusCode: 401 })

    // Row stays unused — attempts incremented but not marked.
    const row = await peekOtpRow(otp_request_id)
    expect(row.used_at).toBeNull()
  })

  it('verifyOtp returns OTP_PROVIDER_FAILED 502 on Fazpass outage (distinct from wrong code)', async () => {
    mockFetch(async (url) => {
      if (url.endsWith('/v1/otp/request')) {
        return jsonResponse(200, { status: true, data: { id: 'fzp-ref-004' } })
      }
      return jsonResponse(503, { status: false, code: '5030503', message: 'gateway unavailable' })
    })

    const phone = uniquePhone()
    const { otp_request_id } = await requestOtp({
      phone, userType: 'customer', ipAddress: '10.0.0.14', channel: 'whatsapp',
    })
    await expect(verifyOtp({ otpRequestId: otp_request_id, code: '424242' }))
      .rejects.toMatchObject({ code: 'OTP_PROVIDER_FAILED', statusCode: 502 })
  })

  it('test-OTP bypass still works even when FAZPASS_ENABLED=true (skips Fazpass entirely)', async () => {
    const fetchSpy = mockFetch(async () => {
      throw new Error('Fazpass MUST NOT be called for bypass rows')
    })

    const phone = uniquePhone()
    await setTestOtpBypassEnabled(true)
    await addTestOtpBypassEntry({
      phone, otp: '999000', user_type: 'customer', label: 'Apple #1',
      expires_at: new Date(Date.now() + 24 * 60 * 60 * 1000).toISOString(),
    })

    const { otp_request_id } = await requestOtp({
      phone, userType: 'customer', ipAddress: '10.0.0.15', channel: 'whatsapp',
    })
    const result = await verifyOtp({ otpRequestId: otp_request_id, code: '999000' })

    expect(result).toEqual({ phone, user_type: 'customer' })
    expect(fetchSpy).not.toHaveBeenCalled()
  })
})