import { describe, it, expect, vi, beforeEach } from 'vitest'
import { NextRequest } from 'next/server'

const mockPayloadCreate = vi.fn()
const mockGetPayload = vi.fn(() => ({ create: mockPayloadCreate }))

vi.mock('payload', () => ({ getPayload: mockGetPayload }))
vi.mock('@payload-config', () => ({ default: {} }))
vi.mock('@/lib/telegram', () => ({ sendLeadAlert: vi.fn().mockResolvedValue(undefined) }))
vi.mock('@/lib/resend', () => ({ sendLeadAlert: vi.fn().mockResolvedValue(undefined) }))

const VALID_LEAD = {
  name: 'Іван Іванов',
  phone: '+380501234567',
  formSource: 'hero-form',
}

function makeRequest(body: unknown, ip = '1.2.3.4'): NextRequest {
  return new NextRequest('http://localhost/api/leads', {
    method: 'POST',
    body: typeof body === 'string' ? body : JSON.stringify(body),
    headers: {
      'content-type': 'application/json',
      'x-forwarded-for': ip,
    },
  })
}

let POST: (req: NextRequest) => Promise<Response>

beforeEach(async () => {
  vi.resetModules()
  mockPayloadCreate.mockReset()
  // Re-import so rateLimit buckets are fresh
  const mod = await import('@/app/api/leads/route')
  POST = mod.POST
})

describe('POST /api/leads', () => {
  it('returns 201 for a valid lead', async () => {
    mockPayloadCreate.mockResolvedValueOnce({ id: 'lead-1' })
    const res = await POST(makeRequest(VALID_LEAD))
    expect(res.status).toBe(201)
    expect((await res.json()).ok).toBe(true)
  })

  it('returns 400 for invalid JSON body', async () => {
    const res = await POST(makeRequest('not-json'))
    expect(res.status).toBe(400)
  })

  it('returns 422 when required fields are missing', async () => {
    const res = await POST(makeRequest({ phone: '123' }))
    expect(res.status).toBe(422)
    const json = await res.json()
    expect(json.error).toBe('Validation failed')
    expect(json.details).toBeDefined()
  })

  it('returns 422 when name is empty string', async () => {
    const res = await POST(makeRequest({ ...VALID_LEAD, name: '' }))
    expect(res.status).toBe(422)
  })

  it('returns 422 when phone is too short', async () => {
    const res = await POST(makeRequest({ ...VALID_LEAD, phone: '12345' }))
    expect(res.status).toBe(422)
  })

  it('returns 422 when email is present but invalid', async () => {
    const res = await POST(makeRequest({ ...VALID_LEAD, email: 'not-an-email' }))
    expect(res.status).toBe(422)
  })

  it('accepts optional UTM params and email', async () => {
    mockPayloadCreate.mockResolvedValueOnce({ id: 'lead-2' })
    const res = await POST(
      makeRequest({
        ...VALID_LEAD,
        email: 'test@example.com',
        utmSource: 'google',
        utmMedium: 'cpc',
        utmCampaign: 'summer',
        utmContent: 'banner',
        utmTerm: 'shoes',
        gclid: 'abc123',
      })
    )
    expect(res.status).toBe(201)
  })

  it('returns 500 when DB create throws', async () => {
    mockPayloadCreate.mockRejectedValueOnce(new Error('DB error'))
    const res = await POST(makeRequest(VALID_LEAD, '9.9.9.1'))
    expect(res.status).toBe(500)
  })

  it('returns 429 after 5 requests from the same IP', async () => {
    mockPayloadCreate.mockResolvedValue({ id: 'x' })
    const ip = '5.5.5.5'
    for (let i = 0; i < 5; i++) {
      await POST(makeRequest(VALID_LEAD, ip))
    }
    const res = await POST(makeRequest(VALID_LEAD, ip))
    expect(res.status).toBe(429)
  })

  it('uses "unknown" when x-forwarded-for header is absent', async () => {
    mockPayloadCreate.mockResolvedValueOnce({ id: 'lead-3' })
    const req = new NextRequest('http://localhost/api/leads', {
      method: 'POST',
      body: JSON.stringify(VALID_LEAD),
      headers: { 'content-type': 'application/json' },
    })
    const res = await POST(req)
    expect(res.status).toBe(201)
  })

  it('accepts a phone number containing valid special characters (+, spaces, dashes, parens)', async () => {
    mockPayloadCreate.mockResolvedValueOnce({ id: 'lead-special' })
    const res = await POST(makeRequest({ ...VALID_LEAD, phone: '+38 (050) 123-45-67' }, '7.7.7.1'))
    expect(res.status).toBe(201)
  })

  it('returns 422 when formSource is an empty string', async () => {
    const res = await POST(makeRequest({ ...VALID_LEAD, formSource: '' }, '7.7.7.2'))
    expect(res.status).toBe(422)
  })

  it('returns 422 when phone contains letters', async () => {
    const res = await POST(makeRequest({ ...VALID_LEAD, phone: '+380abc234567' }, '7.7.7.3'))
    expect(res.status).toBe(422)
  })

  it('accepts name at exactly 100 characters (boundary)', async () => {
    mockPayloadCreate.mockResolvedValueOnce({ id: 'lead-boundary' })
    const res = await POST(makeRequest({ ...VALID_LEAD, name: 'A'.repeat(100) }, '7.7.7.4'))
    expect(res.status).toBe(201)
  })

  it('returns 422 when name exceeds 100 characters', async () => {
    const res = await POST(makeRequest({ ...VALID_LEAD, name: 'A'.repeat(101) }, '7.7.7.5'))
    expect(res.status).toBe(422)
  })

  it('does NOT fire alerts when DB create throws (early return before allSettled)', async () => {
    const { sendLeadAlert: telegramAlert } = await import('@/lib/telegram')
    const { sendLeadAlert: emailAlert } = await import('@/lib/resend')
    vi.mocked(telegramAlert).mockClear()
    vi.mocked(emailAlert).mockClear()

    mockPayloadCreate.mockRejectedValueOnce(new Error('DB error'))
    await POST(makeRequest(VALID_LEAD, '7.7.7.6'))

    expect(vi.mocked(telegramAlert)).not.toHaveBeenCalled()
    expect(vi.mocked(emailAlert)).not.toHaveBeenCalled()
  })

  it('fires Telegram and email alerts with the correct lead data after a successful save', async () => {
    mockPayloadCreate.mockResolvedValueOnce({ id: 'lead-alert' })
    await POST(makeRequest({ ...VALID_LEAD, utmSource: 'google' }, '8.8.8.8'))

    const { sendLeadAlert: telegramAlert } = await import('@/lib/telegram')
    const { sendLeadAlert: emailAlert } = await import('@/lib/resend')

    expect(vi.mocked(telegramAlert)).toHaveBeenCalledWith(
      expect.objectContaining({
        name: VALID_LEAD.name,
        phone: VALID_LEAD.phone,
        formSource: VALID_LEAD.formSource,
        utmSource: 'google',
      })
    )
    expect(vi.mocked(emailAlert)).toHaveBeenCalledWith(
      expect.objectContaining({
        name: VALID_LEAD.name,
        phone: VALID_LEAD.phone,
        formSource: VALID_LEAD.formSource,
      })
    )
  })
})