import { Router } from 'express'
import { z } from 'zod'
import { prisma } from '../lib/prisma'
import { requireCompanyAuth } from '../middleware/requireCompanyAuth'
import { requireTenant } from '../middleware/requireTenant'
import { requireSubscription } from '../middleware/requireSubscription'
import { applyAdditionalDriversToReservation } from '../services/additionalDriverService'
import { applyInsurancesToReservation } from '../services/insuranceService'
import { applyPricingRules } from '../services/pricingRuleService'
import { validateAndFlagLicense, validateLicense } from '../services/licenseValidationService'
import { sendNotification, sendTransactionalEmail } from '../services/notificationService'
import { bookingConfirmedNotif, reviewRequestEmail, type Lang } from '../lib/emailTranslations'
import crypto from 'crypto'

const router = Router()
router.use(requireCompanyAuth, requireTenant, requireSubscription)

const additionalDriverSchema = z.object({
  firstName: z.string().min(1),
  lastName: z.string().min(1),
  email: z.string().email().optional(),
  phone: z.string().optional(),
  driverLicense: z.string().min(1),
  licenseExpiry: z.string().datetime().optional(),
  licenseIssuedAt: z.string().datetime().optional(),
  dateOfBirth: z.string().datetime().optional(),
  nationality: z.string().optional(),
})

const inspectionSchema = z.object({
  mileage: z.number().int().optional(),
  fuelLevel: z.enum(['FULL', 'SEVEN_EIGHTHS', 'THREE_QUARTERS', 'FIVE_EIGHTHS', 'HALF', 'THREE_EIGHTHS', 'QUARTER', 'ONE_EIGHTH', 'EMPTY']),
  fuelCharge: z.number().int().min(0).optional(),
  generalCondition: z.string().optional(),
  employeeNotes: z.string().optional(),
  customerAgreed: z.boolean().default(false),
  damagePoints: z.array(
    z.object({
      viewType: z.enum(['TOP', 'FRONT', 'REAR', 'LEFT', 'RIGHT']),
      x: z.number(),
      y: z.number(),
      damageType: z.enum(['SCRATCH', 'DENT', 'CRACK', 'CHIP', 'MISSING', 'STAIN', 'OTHER']),
      severity: z.enum(['MINOR', 'MODERATE', 'MAJOR']).default('MINOR'),
      description: z.string().optional(),
      isPreExisting: z.boolean().default(false),
    }),
  ).default([]),
})

const createSchema = z.object({
  vehicleId:      z.string().cuid(),
  customerId:     z.string().cuid(),
  startDate:      z.string().datetime(),
  endDate:        z.string().datetime(),
  pickupLocation: z.string().optional(),
  returnLocation: z.string().optional(),
  offerId:        z.string().cuid().optional(),
  promoCodeUsed:  z.string().optional(),
  depositAmount:  z.number().int().min(0).default(0),
  paymentMode:    z.string().max(50).optional(),
  notes:          z.string().optional(),
  selectedInsurancePolicyIds: z.array(z.string()).default([]),
  additionalDrivers: z.array(additionalDriverSchema).default([]),
})

const updateSchema = z.object({
  startDate: z.string().datetime().optional(),
  endDate: z.string().datetime().optional(),
  pickupLocation: z.string().optional().nullable(),
  returnLocation: z.string().optional().nullable(),
  depositAmount: z.number().int().min(0).optional(),
  notes: z.string().optional().nullable(),
  paymentMode: z.string().max(50).optional().nullable(),
  damageChargeAmount: z.number().int().min(0).optional(),
  damageChargeNote: z.string().optional().nullable(),
})

function parseReservationExtras(extras: unknown) {
  if (!extras || typeof extras !== 'object' || Array.isArray(extras)) return {} as Record<string, unknown>
  return { ...(extras as Record<string, unknown>) }
}

function normalizeOptionalString(value: string | null | undefined) {
  const next = typeof value === 'string' ? value.trim() : value
  return next ? next : null
}

function calculateUpdatedInsuranceCharge(
  chargeType: 'PER_DAY' | 'PER_RENTAL' | 'PERCENTAGE_OF_RENTAL',
  chargeValue: number,
  totalDays: number,
  baseRentalAmount: number,
) {
  switch (chargeType) {
    case 'PER_DAY':
      return chargeValue * totalDays
    case 'PER_RENTAL':
      return chargeValue
    case 'PERCENTAGE_OF_RENTAL':
      return Math.round(baseRentalAmount * chargeValue / 100)
    default:
      return 0
  }
}

function calculateUpdatedAdditionalDriverCharge(
  chargeType: 'PER_DAY' | 'FLAT' | 'FREE',
  chargeValue: number,
  totalDays: number,
) {
  switch (chargeType) {
    case 'PER_DAY':
      return chargeValue * totalDays
    case 'FLAT':
      return chargeValue
    default:
      return 0
  }
}

function buildReservationWorkflow(reservation: {
  status: string
  contractNumber: string | null
  invoiceNumber: string | null
  extras: unknown
}) {
  const extras = parseReservationExtras(reservation.extras)
  const closedAt = typeof extras.reservationClosedAt === 'string' ? extras.reservationClosedAt : null
  const closedBy = typeof extras.reservationClosedBy === 'string' ? extras.reservationClosedBy : null
  const contractGenerated = Boolean(reservation.contractNumber || reservation.invoiceNumber)
  const closed = Boolean(closedAt)

  return {
    contractGenerated,
    closed,
    closedAt,
    closedBy,
    coreEditable: !closed && !contractGenerated && ['DRAFT', 'CONFIRMED'].includes(reservation.status),
    returnEditable: !closed && reservation.status === 'COMPLETED',
    checkInInspectionEditable: !closed && ['CONFIRMED', 'ACTIVE'].includes(reservation.status),
    checkOutInspectionEditable: !closed && reservation.status === 'COMPLETED',
  }
}

function serializeReservationForDashboard<T extends {
  extras: unknown
  status: string
  contractNumber: string | null
  invoiceNumber: string | null
}>(reservation: T) {
  const extras = parseReservationExtras(reservation.extras)
  return {
    ...reservation,
    paymentMode: typeof extras.paymentMode === 'string' ? extras.paymentMode : null,
    workflow: buildReservationWorkflow(reservation),
  }
}

function formatDocumentNumber(prefix: string, sequence: number) {
  return `${prefix}-${String(sequence).padStart(6, '0')}`
}

async function ensureReservationDocumentNumbers(companyId: string, reservationId: string) {
  return prisma.$transaction(async (tx) => {
    const reservation = await tx.reservation.findFirstOrThrow({
      where: { id: reservationId, companyId },
      select: { id: true, contractNumber: true, invoiceNumber: true },
    })

    if (reservation.contractNumber && reservation.invoiceNumber) return reservation

    const settings = await tx.contractSettings.upsert({
      where: { companyId },
      update: {},
      create: { companyId },
    })

    const data: { contractNumber?: string; invoiceNumber?: string } = {}
    const settingsUpdate: { lastContractSeq?: number; lastInvoiceSeq?: number } = {}

    if (!reservation.contractNumber) {
      const nextContractSeq = settings.lastContractSeq + 1
      data.contractNumber = formatDocumentNumber(settings.contractPrefix, nextContractSeq)
      settingsUpdate.lastContractSeq = nextContractSeq
    }

    if (!reservation.invoiceNumber) {
      const nextInvoiceSeq = settings.lastInvoiceSeq + 1
      data.invoiceNumber = formatDocumentNumber(settings.invoicePrefix, nextInvoiceSeq)
      settingsUpdate.lastInvoiceSeq = nextInvoiceSeq
    }

    if (Object.keys(settingsUpdate).length > 0) {
      await tx.contractSettings.update({
        where: { companyId },
        data: settingsUpdate,
      })
    }

    return tx.reservation.update({
      where: { id: reservationId },
      data,
      select: { id: true, contractNumber: true, invoiceNumber: true },
    })
  })
}

function buildReservationInvoiceLineItems(reservation: {
  dailyRate: number
  totalDays: number
  discountAmount: number
  depositAmount: number
  pricingRulesApplied: Array<{ name?: string; amount?: number; type?: string }> | null
  insurances: Array<{ id: string; policyName: string; chargeType: string; chargeValue: number; totalCharge: number }>
  additionalDrivers: Array<{ id: string; firstName: string; lastName: string; totalCharge: number }>
  vehicle: { year: number; make: string; model: string }
}) {
  const baseAmount = reservation.dailyRate * reservation.totalDays
  const lineItems = [
    {
      description: `${reservation.vehicle.year} ${reservation.vehicle.make} ${reservation.vehicle.model}`,
      qty: reservation.totalDays,
      unitPrice: reservation.dailyRate,
      total: baseAmount,
      category: 'RENTAL',
    },
    ...reservation.insurances.map((insurance) => ({
      description: insurance.policyName,
      qty: insurance.chargeType === 'PER_DAY' ? reservation.totalDays : 1,
      unitPrice: insurance.chargeType === 'PER_DAY' ? insurance.chargeValue : insurance.totalCharge,
      total: insurance.totalCharge,
      category: 'INSURANCE',
    })),
    ...reservation.additionalDrivers
      .filter((driver) => driver.totalCharge > 0)
      .map((driver) => ({
        description: `Additional driver - ${driver.firstName} ${driver.lastName}`,
        qty: 1,
        unitPrice: driver.totalCharge,
        total: driver.totalCharge,
        category: 'ADDITIONAL_DRIVER',
      })),
    ...((reservation.pricingRulesApplied ?? []).map((rule, index) => ({
      description: rule.name?.trim() || `Pricing adjustment ${index + 1}`,
      qty: 1,
      unitPrice: Number(rule.amount ?? 0),
      total: Number(rule.amount ?? 0),
      category: 'PRICING_RULE',
    }))),
    ...(reservation.discountAmount > 0 ? [{
      description: 'Discount',
      qty: 1,
      unitPrice: -reservation.discountAmount,
      total: -reservation.discountAmount,
      category: 'DISCOUNT',
    }] : []),
    ...(reservation.depositAmount > 0 ? [{
      description: 'Security deposit',
      qty: 1,
      unitPrice: reservation.depositAmount,
      total: reservation.depositAmount,
      category: 'DEPOSIT',
    }] : []),
  ]

  return lineItems
}

async function assertReservationLicenseCompliance(reservationId: string, companyId: string) {
  const reservation = await prisma.reservation.findFirstOrThrow({
    where: { id: reservationId, companyId },
    include: { customer: true, additionalDrivers: true },
  })

  const customerLicense = validateLicense(reservation.customer.licenseExpiry)
  const customerDenied = ['DENIED', 'EXPIRED'].includes(reservation.customer.licenseValidationStatus)
  if (customerDenied || customerLicense.status === 'EXPIRED') {
    throw Object.assign(new Error('Primary driver license is not valid for this reservation'), {
      statusCode: 400,
      code: 'invalid_primary_license',
    })
  }

  if (customerLicense.requiresApproval && reservation.customer.licenseValidationStatus !== 'APPROVED') {
    throw Object.assign(new Error('Primary driver license requires manager approval before this reservation can proceed'), {
      statusCode: 400,
      code: 'primary_license_requires_approval',
    })
  }

  const blockedDriver = reservation.additionalDrivers.find((driver) => {
    if (driver.licenseExpired) return true
    return driver.requiresApproval && !driver.approvedAt
  })

  if (blockedDriver) {
    throw Object.assign(new Error(`Additional driver ${blockedDriver.firstName} ${blockedDriver.lastName} requires approval before this reservation can proceed`), {
      statusCode: 400,
      code: 'additional_driver_requires_approval',
    })
  }
}

router.get('/', async (req, res, next) => {
  try {
    const { status, vehicleId, source, startDate, endDate, page = '1', pageSize = '20' } = req.query as Record<string, string>
    const where: any = { companyId: req.companyId }
    if (status)    where.status = status
    if (vehicleId) where.vehicleId = vehicleId
    if (source)    where.source = source
    if (startDate) where.startDate = { gte: new Date(startDate) }
    if (endDate)   where.endDate   = { lte: new Date(endDate) }

    const [reservations, total] = await Promise.all([
      prisma.reservation.findMany({
        where,
        include: { vehicle: true, customer: true },
        skip: (parseInt(page) - 1) * parseInt(pageSize),
        take: parseInt(pageSize),
        orderBy: { createdAt: 'desc' },
      }),
      prisma.reservation.count({ where }),
    ])

    res.json({
      data: reservations.map((reservation) => serializeReservationForDashboard(reservation)),
      total,
      page: parseInt(page),
      pageSize: parseInt(pageSize),
      totalPages: Math.ceil(total / parseInt(pageSize)),
    })
  } catch (err) { next(err) }
})

router.post('/', async (req, res, next) => {
  try {
    const body = createSchema.parse(req.body)

    // Validate vehicle belongs to this company
    const vehicle = await prisma.vehicle.findFirstOrThrow({ where: { id: body.vehicleId, companyId: req.companyId } })
    const customer = await prisma.customer.findFirstOrThrow({ where: { id: body.customerId, companyId: req.companyId } })

    const start = new Date(body.startDate)
    const end   = new Date(body.endDate)
    const totalDays = Math.ceil((end.getTime() - start.getTime()) / (1000 * 60 * 60 * 24))

    // Check availability
    const conflict = await prisma.reservation.findFirst({
      where: { vehicleId: body.vehicleId, status: { in: ['CONFIRMED', 'ACTIVE'] }, startDate: { lt: end }, endDate: { gt: start } },
    })
    if (conflict) return res.status(409).json({ error: 'vehicle_unavailable', message: 'Vehicle is not available for the selected dates', statusCode: 409 })

    let discountAmount = 0
    let offerId: string | null = body.offerId ?? null

    if (body.promoCodeUsed) {
      const offer = await prisma.offer.findFirst({
        where: { companyId: req.companyId, promoCode: body.promoCodeUsed, isActive: true, validFrom: { lte: new Date() }, validUntil: { gte: new Date() } },
      })
      if (offer) {
        offerId = offer.id
        const base = vehicle.dailyRate * totalDays
        if (offer.type === 'PERCENTAGE') discountAmount = Math.round(base * offer.discountValue / 100)
        else if (offer.type === 'FIXED_AMOUNT') discountAmount = offer.discountValue
        else if (offer.type === 'FREE_DAY')  discountAmount = vehicle.dailyRate * offer.discountValue
        await prisma.offer.update({ where: { id: offer.id }, data: { redemptionCount: { increment: 1 } } })
      }
    }

    const baseAmount = vehicle.dailyRate * totalDays
    const { applied, total: pricingTotal } = await applyPricingRules(req.companyId, body.customerId, body.additionalDrivers as any[], vehicle.dailyRate, totalDays)
    const totalAmount = baseAmount - discountAmount + pricingTotal + body.depositAmount

    const reservation = await prisma.reservation.create({
      data: {
        companyId:      req.companyId,
        vehicleId:      body.vehicleId,
        customerId:     body.customerId,
        startDate:      start,
        endDate:        end,
        pickupLocation: body.pickupLocation ?? null,
        returnLocation: body.returnLocation ?? null,
        offerId,
        promoCodeUsed:  body.promoCodeUsed ?? null,
        source:         'DASHBOARD',
        dailyRate:      vehicle.dailyRate,
        discountAmount,
        totalDays,
        totalAmount,
        depositAmount:  body.depositAmount,
        notes:          body.notes ?? null,
        extras:         body.paymentMode ? { paymentMode: body.paymentMode } : undefined,
        pricingRulesApplied: applied,
        pricingRulesTotal:   pricingTotal,
      },
      include: { vehicle: true, customer: true },
    })

    if (body.selectedInsurancePolicyIds.length > 0) {
      await applyInsurancesToReservation(reservation.id, req.companyId, body.selectedInsurancePolicyIds, totalDays, baseAmount)
    }

    if (body.additionalDrivers.length > 0) {
      await applyAdditionalDriversToReservation(reservation.id, req.companyId, body.additionalDrivers, totalDays)
    }

    // Validate customer license
    await validateAndFlagLicense(body.customerId).catch(() => null)

    res.status(201).json({ data: reservation })
  } catch (err) { next(err) }
})

router.get('/:id', async (req, res, next) => {
  try {
    const reservation = await prisma.reservation.findFirstOrThrow({
      where: { id: req.params.id, companyId: req.companyId },
      include: { vehicle: true, customer: true, insurances: true, additionalDrivers: true, rentalPayments: true, damageReports: true },
    })
    res.json({ data: serializeReservationForDashboard(reservation) })
  } catch (err) { next(err) }
})

router.patch('/:id', async (req, res, next) => {
  try {
    const body = updateSchema.parse(req.body)
    const reservation = await prisma.reservation.findFirstOrThrow({
      where: { id: req.params.id, companyId: req.companyId },
      include: {
        insurances: true,
        additionalDrivers: true,
      },
    })

    if (reservation.status === 'CANCELLED' || reservation.status === 'NO_SHOW') {
      return res.status(400).json({ error: 'invalid_status', message: 'This reservation can no longer be edited', statusCode: 400 })
    }

    const workflow = buildReservationWorkflow(reservation)
    const isReturnEdit = workflow.returnEditable
    const requestedFields = Object.keys(body).filter((key) => body[key as keyof typeof body] !== undefined)
    const bookingFields = ['startDate', 'endDate', 'pickupLocation', 'returnLocation', 'depositAmount', 'notes', 'paymentMode']
    const returnFields = ['returnLocation', 'damageChargeAmount', 'damageChargeNote']

    if (!workflow.coreEditable && !isReturnEdit) {
      return res.status(400).json({ error: 'reservation_locked', message: 'This reservation is locked for editing', statusCode: 400 })
    }

    if (workflow.coreEditable) {
      const invalidFields = requestedFields.filter((field) => !bookingFields.includes(field))
      if (invalidFields.length > 0) {
        return res.status(400).json({ error: 'invalid_fields', message: 'Only booking details can be edited at this stage', statusCode: 400 })
      }

      const nextStartDate = body.startDate ? new Date(body.startDate) : reservation.startDate
      const nextEndDate = body.endDate ? new Date(body.endDate) : reservation.endDate
      const totalDays = Math.ceil((nextEndDate.getTime() - nextStartDate.getTime()) / (1000 * 60 * 60 * 24))

      if (nextEndDate <= nextStartDate || totalDays <= 0) {
        return res.status(400).json({ error: 'invalid_dates', message: 'End date must be after start date', statusCode: 400 })
      }

      if (body.startDate || body.endDate) {
        const conflict = await prisma.reservation.findFirst({
          where: {
            id: { not: reservation.id },
            vehicleId: reservation.vehicleId,
            status: { in: ['DRAFT', 'CONFIRMED', 'ACTIVE'] },
            startDate: { lt: nextEndDate },
            endDate: { gt: nextStartDate },
          },
        })

        if (conflict) {
          return res.status(409).json({ error: 'vehicle_unavailable', message: 'Vehicle is not available for the selected dates', statusCode: 409 })
        }
      }

      const baseAmount = reservation.dailyRate * totalDays
      const { applied, total: pricingRulesTotal } = await applyPricingRules(
        req.companyId,
        reservation.customerId,
        reservation.additionalDrivers.map((driver) => ({
          dateOfBirth: driver.dateOfBirth,
          licenseIssuedAt: driver.licenseIssuedAt,
        })),
        reservation.dailyRate,
        totalDays,
      )

      const insuranceUpdates = reservation.insurances.map((insurance) => ({
        id: insurance.id,
        totalCharge: calculateUpdatedInsuranceCharge(insurance.chargeType, insurance.chargeValue, totalDays, baseAmount),
      }))
      const additionalDriverUpdates = reservation.additionalDrivers.map((driver) => ({
        id: driver.id,
        totalCharge: calculateUpdatedAdditionalDriverCharge(driver.chargeType, driver.chargeValue, totalDays),
      }))

      const insuranceTotal = insuranceUpdates.reduce((sum, insurance) => sum + insurance.totalCharge, 0)
      const additionalDriverTotal = additionalDriverUpdates.reduce((sum, driver) => sum + driver.totalCharge, 0)
      const depositAmount = body.depositAmount ?? reservation.depositAmount
      const totalAmount = baseAmount - reservation.discountAmount + pricingRulesTotal + insuranceTotal + additionalDriverTotal + depositAmount

      const extras = parseReservationExtras(reservation.extras)
      if (body.paymentMode !== undefined) {
        const nextPaymentMode = normalizeOptionalString(body.paymentMode)
        if (nextPaymentMode) extras.paymentMode = nextPaymentMode
        else delete extras.paymentMode
      }

      await prisma.$transaction([
        prisma.reservation.update({
          where: { id: reservation.id },
          data: {
            startDate: nextStartDate,
            endDate: nextEndDate,
            totalDays,
            pickupLocation: body.pickupLocation !== undefined ? normalizeOptionalString(body.pickupLocation) : reservation.pickupLocation,
            returnLocation: body.returnLocation !== undefined ? normalizeOptionalString(body.returnLocation) : reservation.returnLocation,
            depositAmount,
            notes: body.notes !== undefined ? normalizeOptionalString(body.notes) : reservation.notes,
            pricingRulesApplied: applied,
            pricingRulesTotal,
            insuranceTotal,
            additionalDriverTotal,
            totalAmount,
            extras: (Object.keys(extras).length > 0 ? extras : {}) as any,
          },
        }),
        ...insuranceUpdates.map((insurance) =>
          prisma.reservationInsurance.update({
            where: { id: insurance.id },
            data: { totalCharge: insurance.totalCharge },
          })
        ),
        ...additionalDriverUpdates.map((driver) =>
          prisma.additionalDriver.update({
            where: { id: driver.id },
            data: { totalCharge: driver.totalCharge },
          })
        ),
      ])
    } else {
      const invalidFields = requestedFields.filter((field) => !returnFields.includes(field))
      if (invalidFields.length > 0) {
        return res.status(400).json({ error: 'invalid_fields', message: 'Only return details can be edited after vehicle return', statusCode: 400 })
      }

      await prisma.reservation.update({
        where: { id: reservation.id },
        data: {
          returnLocation: body.returnLocation !== undefined ? normalizeOptionalString(body.returnLocation) : reservation.returnLocation,
          damageChargeAmount: body.damageChargeAmount !== undefined ? body.damageChargeAmount : reservation.damageChargeAmount,
          damageChargeNote: body.damageChargeNote !== undefined ? normalizeOptionalString(body.damageChargeNote) : reservation.damageChargeNote,
        },
      })
    }

    const updated = await prisma.reservation.findFirstOrThrow({
      where: { id: req.params.id, companyId: req.companyId },
      include: { vehicle: true, customer: true, insurances: true, additionalDrivers: true, rentalPayments: true, damageReports: true },
    })

    res.json({ data: serializeReservationForDashboard(updated) })
  } catch (err) { next(err) }
})

router.get('/:id/contract', async (req, res, next) => {
  try {
    await ensureReservationDocumentNumbers(req.companyId, req.params.id)

    const reservation = await prisma.reservation.findFirstOrThrow({
      where: { id: req.params.id, companyId: req.companyId },
      include: {
        vehicle: true,
        customer: true,
        insurances: true,
        additionalDrivers: true,
        rentalPayments: { orderBy: { createdAt: 'asc' } },
        inspections: { include: { damagePoints: true }, orderBy: { inspectedAt: 'asc' } },
        company: {
          include: {
            brand: true,
            contractSettings: true,
            accountingSettings: true,
          },
        },
      },
    })

    const contractSettings = reservation.company.contractSettings ?? await prisma.contractSettings.upsert({
      where: { companyId: req.companyId },
      update: {},
      create: { companyId: req.companyId },
    })

    const paymentMode = reservation.extras && typeof reservation.extras === 'object' && !Array.isArray(reservation.extras)
      ? String((reservation.extras as Record<string, unknown>).paymentMode ?? '')
      : ''

    const invoiceLineItems = buildReservationInvoiceLineItems({
      dailyRate: reservation.dailyRate,
      totalDays: reservation.totalDays,
      discountAmount: reservation.discountAmount,
      depositAmount: reservation.depositAmount,
      pricingRulesApplied: Array.isArray(reservation.pricingRulesApplied) ? reservation.pricingRulesApplied as Array<{ name?: string; amount?: number; type?: string }> : [],
      insurances: reservation.insurances,
      additionalDrivers: reservation.additionalDrivers,
      vehicle: reservation.vehicle,
    })

    const subtotal = invoiceLineItems.reduce((sum, item) => sum + item.total, 0)
    const taxes = contractSettings.showTax && contractSettings.taxRate
      ? [{
          label: contractSettings.taxLabel?.trim() || 'Tax',
          rate: contractSettings.taxRate,
          amount: Math.round(subtotal * contractSettings.taxRate / 100),
        }]
      : []
    const taxTotal = taxes.reduce((sum, tax) => sum + tax.amount, 0)
    const grandTotal = subtotal + taxTotal
    const amountPaid = reservation.rentalPayments
      .filter((payment) => payment.status === 'SUCCEEDED')
      .reduce((sum, payment) => sum + payment.amount, 0)

    const checkInInspection = reservation.inspections.find((inspection) => inspection.type === 'CHECKIN') ?? null
    const checkOutInspection = reservation.inspections.find((inspection) => inspection.type === 'CHECKOUT') ?? null

    res.json({
      data: {
        reservationId: reservation.id,
        contractLocale: reservation.company.brand?.defaultLocale ?? 'en',
        contractNumber: reservation.contractNumber,
        invoiceNumber: reservation.invoiceNumber,
        generatedAt: new Date().toISOString(),
        status: reservation.status,
        paymentStatus: reservation.paymentStatus,
        paymentMode: paymentMode || null,
        notes: reservation.notes,
        company: {
          name: reservation.company.brand?.displayName ?? reservation.company.name,
          legalName: contractSettings.legalName || reservation.company.name,
          email: reservation.company.brand?.publicEmail ?? reservation.company.email,
          phone: reservation.company.brand?.publicPhone ?? reservation.company.phone,
          address: reservation.company.brand?.publicAddress ?? reservation.company.address ?? null,
          city: reservation.company.brand?.publicCity ?? null,
          country: reservation.company.brand?.publicCountry ?? null,
          registrationNumber: contractSettings.registrationNumber,
          taxId: contractSettings.taxId,
          logoUrl: reservation.company.brand?.logoUrl ?? null,
        },
        driver: {
          firstName: reservation.customer.firstName,
          lastName: reservation.customer.lastName,
          email: reservation.customer.email,
          phone: reservation.customer.phone,
          dateOfBirth: reservation.customer.dateOfBirth,
          driverLicense: reservation.customer.driverLicense,
          licenseCountry: reservation.customer.licenseCountry,
          licenseCategory: reservation.customer.licenseCategory,
          licenseIssuedAt: reservation.customer.licenseIssuedAt,
          licenseExpiry: reservation.customer.licenseExpiry,
          nationality: reservation.customer.nationality,
        },
        additionalDrivers: reservation.additionalDrivers.map((driver) => ({
          id: driver.id,
          firstName: driver.firstName,
          lastName: driver.lastName,
          email: driver.email,
          phone: driver.phone,
          driverLicense: driver.driverLicense,
          licenseIssuedAt: driver.licenseIssuedAt,
          licenseExpiry: driver.licenseExpiry,
          licenseCountry: driver.nationality,
          dateOfBirth: driver.dateOfBirth,
          totalCharge: driver.totalCharge,
        })),
        vehicle: {
          make: reservation.vehicle.make,
          model: reservation.vehicle.model,
          year: reservation.vehicle.year,
          color: reservation.vehicle.color,
          licensePlate: reservation.vehicle.licensePlate,
          vin: reservation.vehicle.vin,
          category: reservation.vehicle.category,
        },
        rentalPeriod: {
          startDate: reservation.startDate,
          endDate: reservation.endDate,
          totalDays: reservation.totalDays,
          pickupLocation: reservation.pickupLocation,
          returnLocation: reservation.returnLocation,
        },
        insurance: {
          total: reservation.insuranceTotal,
          policies: reservation.insurances.map((insurance) => ({
            id: insurance.id,
            name: insurance.policyName,
            chargeType: insurance.chargeType,
            unitPrice: insurance.chargeValue,
            totalCharge: insurance.totalCharge,
          })),
        },
        inspections: {
          checkIn: checkInInspection,
          checkOut: checkOutInspection,
        },
        terms: {
          terms: contractSettings.terms,
          fuelPolicy: contractSettings.fuelPolicy,
          fuelPolicyType: contractSettings.fuelPolicyType,
          depositPolicy: contractSettings.depositPolicy,
          lateFeePolicy: contractSettings.lateFeePolicy,
          damagePolicy: contractSettings.damagePolicy,
          footerNote: contractSettings.contractFooterNote,
          signatureRequired: contractSettings.signatureRequired,
        },
        invoice: {
          currency: reservation.company.accountingSettings?.currency ?? reservation.company.brand?.defaultCurrency ?? 'MAD',
          lineItems: invoiceLineItems,
          subtotal,
          taxes,
          taxTotal,
          total: grandTotal,
          amountPaid,
          balanceDue: grandTotal - amountPaid,
          payments: reservation.rentalPayments.map((payment) => ({
            id: payment.id,
            amount: payment.amount,
            currency: payment.currency,
            type: payment.type,
            status: payment.status,
            provider: payment.paymentProvider,
            paymentMethod: payment.paymentMethod,
            paidAt: payment.paidAt,
            createdAt: payment.createdAt,
          })),
        },
      },
    })
  } catch (err) { next(err) }
})

router.post('/:id/confirm', async (req, res, next) => {
  try {
    const reservation = await prisma.reservation.findFirstOrThrow({ where: { id: req.params.id, companyId: req.companyId } })
    if (reservation.status !== 'DRAFT') return res.status(400).json({ error: 'invalid_status', message: 'Only DRAFT reservations can be confirmed', statusCode: 400 })
    await assertReservationLicenseCompliance(reservation.id, req.companyId)

    const updated = await prisma.reservation.update({ where: { id: req.params.id }, data: { status: 'CONFIRMED' } })

    // Notify
    const [customer, companyBrand] = await Promise.all([
      prisma.customer.findUniqueOrThrow({ where: { id: reservation.customerId } }),
      prisma.brandSettings.findUnique({ where: { companyId: req.companyId }, select: { defaultLocale: true } }),
    ])
    const lang = ((companyBrand?.defaultLocale ?? 'fr') as Lang)
    await sendNotification({ type: 'BOOKING_CONFIRMED', title: bookingConfirmedNotif.title(lang), body: bookingConfirmedNotif.body(lang), companyId: req.companyId, email: customer.email, channels: ['EMAIL', 'IN_APP'], locale: lang }).catch(() => null)

    res.json({ data: updated })
  } catch (err) { next(err) }
})

router.post('/:id/checkin', async (req, res, next) => {
  try {
    const { mileage } = z.object({ mileage: z.number().int().optional() }).parse(req.body)
    const reservation = await prisma.reservation.findFirstOrThrow({ where: { id: req.params.id, companyId: req.companyId } })
    if (reservation.status !== 'CONFIRMED') return res.status(400).json({ error: 'invalid_status', message: 'Only CONFIRMED reservations can be checked in', statusCode: 400 })
    await assertReservationLicenseCompliance(reservation.id, req.companyId)
    const updated = await prisma.reservation.update({ where: { id: req.params.id }, data: { status: 'ACTIVE', checkedInAt: new Date(), checkInMileage: mileage ?? null } })
    await prisma.vehicle.update({ where: { id: reservation.vehicleId }, data: { status: 'RENTED' } })
    res.json({ data: updated })
  } catch (err) { next(err) }
})

router.post('/:id/checkout', async (req, res, next) => {
  try {
    const { mileage } = z.object({ mileage: z.number().int().optional() }).parse(req.body)
    const reservation = await prisma.reservation.findFirstOrThrow({
      where: { id: req.params.id, companyId: req.companyId },
      include: { vehicle: true },
    })
    if (reservation.status !== 'ACTIVE') return res.status(400).json({ error: 'invalid_status', message: 'Only ACTIVE reservations can be checked out', statusCode: 400 })

    const reviewToken = crypto.randomBytes(32).toString('hex')
    const updated = await prisma.reservation.update({
      where: { id: req.params.id },
      data: { status: 'COMPLETED', checkedOutAt: new Date(), checkOutMileage: mileage ?? null, reviewToken },
    })
    await prisma.vehicle.update({ where: { id: reservation.vehicleId }, data: { status: 'AVAILABLE', mileage: mileage ?? undefined } })

    // Send "How was your rental?" email with secure one-time review link
    const customer = await prisma.customer.findUniqueOrThrow({ where: { id: reservation.customerId } })
    const company = await prisma.company.findUnique({ where: { id: req.companyId }, include: { brand: { select: { displayName: true, defaultLocale: true } } } })
    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} ${reservation.vehicle.model}`
    const marketplaceUrl = process.env.MARKETPLACE_URL ?? process.env.NEXT_PUBLIC_MARKETPLACE_URL ?? 'http://localhost:3000'
    const reviewUrl = `${marketplaceUrl}/review?token=${reviewToken}`
    const reviewOpts = { firstName: customer.firstName, companyName, vehicleLabel, reviewUrl }

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

    res.json({ data: updated })
  } catch (err) { next(err) }
})

router.post('/:id/close', async (req, res, next) => {
  try {
    const reservation = await prisma.reservation.findFirstOrThrow({
      where: { id: req.params.id, companyId: req.companyId },
    })
    const workflow = buildReservationWorkflow(reservation)

    if (reservation.status !== 'COMPLETED') {
      return res.status(400).json({ error: 'invalid_status', message: 'Only completed reservations can be closed', statusCode: 400 })
    }

    if (workflow.closed) {
      return res.status(400).json({ error: 'already_closed', message: 'This reservation is already closed', statusCode: 400 })
    }

    const extras = parseReservationExtras(reservation.extras)
    extras.reservationClosedAt = new Date().toISOString()
    extras.reservationClosedBy = `${req.employee.firstName} ${req.employee.lastName}`

    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 },
    })

    res.json({ data: serializeReservationForDashboard(updated) })
  } catch (err) { next(err) }
})

router.post('/:id/cancel', async (req, res, next) => {
  try {
    const { reason } = z.object({ reason: z.string().optional() }).parse(req.body)
    const reservation = await prisma.reservation.findFirstOrThrow({ where: { id: req.params.id, companyId: req.companyId } })
    if (['COMPLETED', 'CANCELLED'].includes(reservation.status)) {
      return res.status(400).json({ error: 'invalid_status', message: 'Reservation cannot be cancelled', statusCode: 400 })
    }
    const updated = await prisma.reservation.update({ where: { id: req.params.id }, data: { status: 'CANCELLED', cancelReason: reason ?? null, cancelledBy: 'COMPANY' } })
    if (['CONFIRMED', 'ACTIVE'].includes(reservation.status)) {
      await prisma.vehicle.update({ where: { id: reservation.vehicleId }, data: { status: 'AVAILABLE' } })
    }
    res.json({ data: updated })
  } catch (err) { next(err) }
})

router.get('/:id/billing', async (req, res, next) => {
  try {
    const reservation = await prisma.reservation.findFirstOrThrow({
      where: { id: req.params.id, companyId: req.companyId },
      include: { vehicle: true, insurances: true, additionalDrivers: true },
    })

    const baseAmount = reservation.dailyRate * reservation.totalDays
    const lineItems = [
      { description: `${reservation.vehicle.year} ${reservation.vehicle.make} ${reservation.vehicle.model} — ${reservation.totalDays} day(s)`, qty: reservation.totalDays, unitPrice: reservation.dailyRate, total: baseAmount, category: 'RENTAL' },
      ...reservation.insurances.map((ins: (typeof reservation.insurances)[number]) => ({ description: ins.policyName, qty: ins.chargeType === 'PER_DAY' ? reservation.totalDays : 1, unitPrice: ins.chargeType === 'PER_DAY' ? ins.chargeValue : ins.totalCharge, total: ins.totalCharge, category: 'INSURANCE' })),
      ...reservation.additionalDrivers.filter((d: (typeof reservation.additionalDrivers)[number]) => d.totalCharge > 0).map((d: (typeof reservation.additionalDrivers)[number]) => ({ description: `Additional Driver — ${d.firstName} ${d.lastName}`, qty: 1, unitPrice: d.totalCharge, total: d.totalCharge, category: 'ADDITIONAL_DRIVER' })),
      ...(reservation.depositAmount > 0 ? [{ description: 'Security Deposit (refundable)', qty: 1, unitPrice: reservation.depositAmount, total: reservation.depositAmount, category: 'DEPOSIT' }] : []),
    ]

    const grandTotal = lineItems.reduce((s, i) => s + i.total, 0) - reservation.discountAmount

    res.json({ data: { lineItems, discountAmount: reservation.discountAmount, pricingRulesApplied: reservation.pricingRulesApplied, pricingRulesTotal: reservation.pricingRulesTotal, grandTotal } })
  } catch (err) { next(err) }
})

router.get('/:id/inspections', async (req, res, next) => {
  try {
    const inspections = await prisma.damageInspection.findMany({
      where: { reservationId: req.params.id, companyId: req.companyId },
      include: { damagePoints: true },
      orderBy: { inspectedAt: 'asc' },
    })
    res.json({ data: inspections })
  } catch (err) { next(err) }
})

router.put('/:id/inspections/:type', async (req, res, next) => {
  try {
    const type = z.enum(['CHECKIN', 'CHECKOUT']).parse(req.params.type.toUpperCase())
    const body = inspectionSchema.parse(req.body)
    const reservation = await prisma.reservation.findFirstOrThrow({
      where: { id: req.params.id, companyId: req.companyId },
      include: { vehicle: true, customer: true },
    })
    const workflow = buildReservationWorkflow(reservation)

    if (workflow.closed) {
      return res.status(400).json({ error: 'reservation_closed', message: 'This reservation has already been closed', statusCode: 400 })
    }

    if (type === 'CHECKIN' && !workflow.checkInInspectionEditable) {
      return res.status(400).json({ error: 'invalid_status', message: 'Check-in inspection is not editable at this stage', statusCode: 400 })
    }

    if (type === 'CHECKOUT' && !workflow.checkOutInspectionEditable) {
      return res.status(400).json({ error: 'invalid_status', message: 'Check-out inspection is only editable after the vehicle is returned', statusCode: 400 })
    }

    const inspection = await prisma.damageInspection.upsert({
      where: { reservationId_type: { reservationId: reservation.id, type } },
      update: {
        mileage: body.mileage ?? null,
        fuelLevel: body.fuelLevel,
        fuelCharge: body.fuelCharge ?? null,
        generalCondition: body.generalCondition ?? null,
        employeeNotes: body.employeeNotes ?? null,
        customerAgreed: body.customerAgreed,
        inspectedBy: `${req.employee.firstName} ${req.employee.lastName}`,
        inspectedAt: new Date(),
        damagePoints: {
          deleteMany: {},
          create: body.damagePoints,
        },
      },
      create: {
        reservationId: reservation.id,
        companyId: req.companyId,
        type,
        mileage: body.mileage ?? null,
        fuelLevel: body.fuelLevel,
        fuelCharge: body.fuelCharge ?? null,
        generalCondition: body.generalCondition ?? null,
        employeeNotes: body.employeeNotes ?? null,
        customerAgreed: body.customerAgreed,
        inspectedBy: `${req.employee.firstName} ${req.employee.lastName}`,
        damagePoints: {
          create: body.damagePoints,
        },
      },
      include: { damagePoints: true },
    })

    await prisma.damageReport.upsert({
      where: { reservationId_type: { reservationId: reservation.id, type } },
      update: {
        damages: body.damagePoints.map((point) => ({
          viewType: point.viewType,
          x: point.x,
          y: point.y,
          damageType: point.damageType,
          severity: point.severity,
          note: point.description ?? '',
          isPreExisting: point.isPreExisting,
        })),
        fuelLevel: body.fuelLevel,
        mileage: body.mileage ?? null,
        inspectedAt: new Date(),
        inspectedBy: `${req.employee.firstName} ${req.employee.lastName}`,
        customerSignedAt: body.customerAgreed ? new Date() : null,
        customerName: `${reservation.customer.firstName} ${reservation.customer.lastName}`,
      },
      create: {
        reservationId: reservation.id,
        companyId: req.companyId,
        type,
        damages: body.damagePoints.map((point) => ({
          viewType: point.viewType,
          x: point.x,
          y: point.y,
          damageType: point.damageType,
          severity: point.severity,
          note: point.description ?? '',
          isPreExisting: point.isPreExisting,
        })),
        photos: [],
        fuelLevel: body.fuelLevel,
        mileage: body.mileage ?? null,
        inspectedAt: new Date(),
        inspectedBy: `${req.employee.firstName} ${req.employee.lastName}`,
        customerSignedAt: body.customerAgreed ? new Date() : null,
        customerName: `${reservation.customer.firstName} ${reservation.customer.lastName}`,
      },
    })

    await prisma.reservation.update({
      where: { id: reservation.id },
      data: type === 'CHECKIN'
        ? {
            checkInMileage: body.mileage ?? null,
            checkInFuelLevel: body.fuelLevel,
          }
        : {
            checkOutMileage: body.mileage ?? null,
            checkOutFuelLevel: body.fuelLevel,
          },
    })

    res.json({ data: inspection })
  } catch (err) { next(err) }
})

router.patch('/:id/additional-drivers/:driverId/approval', async (req, res, next) => {
  try {
    const { approved, note } = z.object({ approved: z.boolean(), note: z.string().optional() }).parse(req.body)
    const driver = await prisma.additionalDriver.findFirstOrThrow({
      where: { id: req.params.driverId, reservationId: req.params.id, companyId: req.companyId },
    })

    const updated = await prisma.additionalDriver.update({
      where: { id: driver.id },
      data: {
        approvedAt: approved ? new Date() : null,
        approvedBy: approved ? `${req.employee.firstName} ${req.employee.lastName}` : null,
        approvalNote: note ?? driver.approvalNote,
      },
    })

    res.json({ data: updated })
  } catch (err) { next(err) }
})

export default router