import crypto from 'crypto'
import { prisma } from '../../lib/prisma'
import { AppError } from '../../http/errors'
import { validateLicense } from '../../services/licenseValidationService'
import { sendNotification, sendTransactionalEmail } from '../../services/notificationService'
import { reviewRequestEmail, type Lang } from '../../lib/emailTranslations'
import { coerceNotificationLocale } from '../../services/notificationLocalizationService'
import { buildReservationWorkflow, parseReservationExtras, serializeReservationForDashboard } from './reservation.presenter'
import * as repo from './reservation.repo'

async function assertLicenseCompliance(reservationId: string, companyId: string) {
  const reservation = await repo.findForLicenseCheck(reservationId, companyId)

  const customerLicense = validateLicense(reservation.customer.licenseExpiry)
  const customerDenied  = ['DENIED', 'EXPIRED'].includes(reservation.customer.licenseValidationStatus)
  if (customerDenied || customerLicense.status === 'EXPIRED') {
    throw new AppError('Primary driver license is not valid for this reservation', 400, 'invalid_primary_license')
  }
  if (customerLicense.requiresApproval && reservation.customer.licenseValidationStatus !== 'APPROVED') {
    throw new AppError('Primary driver license requires manager approval before this reservation can proceed', 400, 'primary_license_requires_approval')
  }

  const blockedDriver = reservation.additionalDrivers.find((d: any) => {
    if (d.licenseExpired) return true
    return d.requiresApproval && !d.approvedAt
  })
  if (blockedDriver) {
    throw new AppError(
      `Additional driver ${blockedDriver.firstName} ${blockedDriver.lastName} requires approval before this reservation can proceed`,
      400,
      'additional_driver_requires_approval',
    )
  }
}

export async function confirmReservation(id: string, companyId: string) {
  const reservation = await repo.findByIdSimple(id, companyId)
  if (reservation.status !== 'DRAFT') throw new AppError('Only DRAFT reservations can be confirmed', 400, 'invalid_status')
  await assertLicenseCompliance(reservation.id, companyId)

  const updated = await repo.updateById(id, { status: 'CONFIRMED' })

  const [customer, company, vehicle] = await Promise.all([
    repo.findCustomerById(reservation.customerId),
    repo.findCompanyWithBrand(companyId),
    repo.findVehicle(reservation.vehicleId, companyId),
  ])
  const fallbackLocale = coerceNotificationLocale(company?.brand?.defaultLocale)
  await sendNotification({
    type: 'BOOKING_CONFIRMED',
    companyId,
    renterId: reservation.renterId ?? undefined,
    email: customer.email,
    channels: ['EMAIL', 'IN_APP'],
    locale: reservation.renterId ? undefined : fallbackLocale,
    templateKey: 'booking.confirmed',
    templateVariables: {
      firstName: customer.firstName,
      companyName: company?.brand?.displayName ?? company?.name ?? 'RentalDriveGo',
      startDate: reservation.startDate,
      endDate: reservation.endDate,
      vehicleName: `${vehicle.year} ${vehicle.make} ${vehicle.model}`,
    },
  }).catch(() => null)

  return updated
}

export async function checkinReservation(id: string, companyId: string, mileage?: number) {
  const reservation = await repo.findByIdSimple(id, companyId)
  if (reservation.status !== 'CONFIRMED') throw new AppError('Only CONFIRMED reservations can be checked in', 400, 'invalid_status')
  await assertLicenseCompliance(reservation.id, companyId)

  const updated = await repo.updateById(id, {
    status: 'ACTIVE',
    checkedInAt: new Date(),
    checkInMileage: mileage ?? null,
  })
  await repo.updateVehicleStatus(reservation.vehicleId, 'RENTED')
  return updated
}

export async function checkoutReservation(id: string, companyId: string, mileage?: number) {
  const reservation = await repo.findByIdForCheckout(id, companyId)
  if (reservation.status !== 'ACTIVE') throw new AppError('Only ACTIVE reservations can be checked out', 400, 'invalid_status')

  const reviewToken = crypto.randomBytes(32).toString('hex')
  const updated = await repo.updateById(id, {
    status: 'COMPLETED',
    checkedOutAt: new Date(),
    checkOutMileage: mileage ?? null,
    reviewToken,
  })
  await repo.updateVehicleStatus(reservation.vehicleId, 'AVAILABLE', mileage)

  const [customer, company] = await Promise.all([
    repo.findCustomerById(reservation.customerId),
    repo.findCompanyWithBrand(companyId),
  ])
  const lang        = (company?.brand?.defaultLocale ?? 'fr') as Lang
  const companyName = company?.brand?.displayName ?? company?.name ?? 'the rental company'
  const vehicleLabel = `${reservation.vehicle.year} ${reservation.vehicle.make} ${reservation.vehicle.model}`
  const reviewUrl = `${process.env.MARKETPLACE_URL ?? process.env.NEXT_PUBLIC_MARKETPLACE_URL ?? 'http://localhost:3000'}/review?token=${reviewToken}`

  sendTransactionalEmail({
    to: customer.email,
    subject: reviewRequestEmail.subject(vehicleLabel, lang),
    html: reviewRequestEmail.html({ firstName: customer.firstName, companyName, vehicleLabel, reviewUrl }, lang),
    text: reviewRequestEmail.text({ firstName: customer.firstName, companyName, vehicleLabel, reviewUrl }, lang),
  }).catch(() => null)

  return updated
}

export async function closeReservation(id: string, companyId: string, closedBy: string) {
  const reservation = await repo.findForClose(id, companyId)
  const workflow    = buildReservationWorkflow(reservation)

  if (reservation.status !== 'COMPLETED') throw new AppError('Only completed reservations can be closed', 400, 'invalid_status')
  if (workflow.closed) throw new AppError('This reservation is already closed', 400, 'already_closed')

  const extras = parseReservationExtras(reservation.extras)
  extras.reservationClosedAt = new Date().toISOString()
  extras.reservationClosedBy = closedBy

  const updated = await prisma.reservation.update({
    where: { id: reservation.id },
    data: { extras: extras as any },
    include: { vehicle: true, customer: true, insurances: true, additionalDrivers: true, rentalPayments: true, damageReports: true },
  })
  return serializeReservationForDashboard(updated)
}

export async function cancelReservation(id: string, companyId: string, reason?: string) {
  const reservation = await repo.findByIdSimple(id, companyId)
  if (['COMPLETED', 'CANCELLED'].includes(reservation.status)) {
    throw new AppError('Reservation cannot be cancelled', 400, 'invalid_status')
  }
  const updated = await repo.updateById(id, { status: 'CANCELLED', cancelReason: reason ?? null, cancelledBy: 'COMPANY' })
  if (['CONFIRMED', 'ACTIVE'].includes(reservation.status)) {
    await repo.updateVehicleStatus(reservation.vehicleId, 'AVAILABLE')
  }
  return updated
}