import express from 'express'
import cors from 'cors'
import helmet from 'helmet'
import morgan from 'morgan'
import http from 'http'
import { Server as SocketIOServer } from 'socket.io'
import cron from 'node-cron'
import { redis } from './lib/redis'
import { prisma } from './lib/prisma'

// ─── Routes ───────────────────────────────────────────────────
import webhookRouter     from './routes/webhooks'
import renterAuthRouter  from './routes/auth.renter'
import vehiclesRouter    from './routes/vehicles'
import reservationsRouter from './routes/reservations'
import teamRouter        from './routes/team'
import customersRouter   from './routes/customers'
import offersRouter      from './routes/offers'
import analyticsRouter   from './routes/analytics'
import notificationsRouter from './routes/notifications'
import marketplaceRouter from './routes/marketplace'
import adminRouter       from './routes/admin'

const app  = express()
const server = http.createServer(app)

// ─── Socket.io ────────────────────────────────────────────────
const io = new SocketIOServer(server, {
  cors: { origin: '*', methods: ['GET', 'POST'] },
})

io.on('connection', (socket) => {
  const userId = socket.handshake.auth?.userId as string | undefined
  if (userId) {
    socket.join(`user:${userId}`)
  }
})

// Redis pub/sub → broadcast to connected clients
const subscriber = redis.duplicate()
subscriber.psubscribe('notifications:*', (err) => {
  if (err) console.error('[Redis] Subscribe error:', err)
})
subscriber.on('pmessage', (_pattern, channel, message) => {
  const userId = channel.replace('notifications:', '')
  io.to(`user:${userId}`).emit('notification', JSON.parse(message))
})

// ─── Middleware ────────────────────────────────────────────────
// Webhook must use raw body BEFORE express.json()
app.use('/api/v1/webhooks', express.raw({ type: 'application/json' }), webhookRouter)

app.use(helmet())
app.use(cors({ origin: process.env.CORS_ORIGINS?.split(',') ?? '*', credentials: true }))
app.use(morgan('combined'))
app.use(express.json({ limit: '10mb' }))

// ─── API Routes ───────────────────────────────────────────────
const v1 = '/api/v1'

app.use(`${v1}/auth/renter`,   renterAuthRouter)
app.use(`${v1}/vehicles`,      vehiclesRouter)
app.use(`${v1}/reservations`,  reservationsRouter)
app.use(`${v1}/team`,          teamRouter)
app.use(`${v1}/customers`,     customersRouter)
app.use(`${v1}/offers`,        offersRouter)
app.use(`${v1}/analytics`,     analyticsRouter)
app.use(`${v1}/notifications`, notificationsRouter)
app.use(`${v1}/marketplace`,   marketplaceRouter)
app.use(`${v1}/admin`,         adminRouter)

// ─── Health check ─────────────────────────────────────────────
app.get('/health', (_req, res) => {
  res.json({ status: 'ok', version: '1.0.0', timestamp: new Date().toISOString() })
})

// ─── Error handler ────────────────────────────────────────────
app.use((err: any, _req: express.Request, res: express.Response, _next: express.NextFunction) => {
  const statusCode = err.statusCode ?? 500
  const message    = err.message ?? 'Internal server error'
  const code       = err.code ?? 'internal_error'

  if (statusCode >= 500) {
    console.error('[API Error]', err)
  }

  // Zod validation error
  if (err.name === 'ZodError') {
    return res.status(400).json({ error: 'validation_error', message: 'Invalid request body', issues: err.issues, statusCode: 400 })
  }

  // Prisma not found
  if (err.code === 'P2025') {
    return res.status(404).json({ error: 'not_found', message: 'Resource not found', statusCode: 404 })
  }

  // Prisma unique constraint
  if (err.code === 'P2002') {
    return res.status(409).json({ error: 'conflict', message: 'A resource with this value already exists', statusCode: 409 })
  }

  res.status(statusCode).json({ error: code, message, statusCode })
})

// ─── Scheduled jobs ───────────────────────────────────────────

// Daily: flag expiring/expired licenses
cron.schedule('0 8 * * *', async () => {
  const customers = await prisma.customer.findMany({ where: { licenseExpiry: { not: null } } })
  for (const c of customers) {
    if (!c.licenseExpiry) continue
    const daysLeft = Math.ceil((c.licenseExpiry.getTime() - Date.now()) / (1000 * 60 * 60 * 24))
    const expired = c.licenseExpiry <= new Date()
    const expiring = !expired && daysLeft < 90
    if (expired !== c.licenseExpired || expiring !== c.licenseExpiringSoon) {
      await prisma.customer.update({ where: { id: c.id }, data: { licenseExpired: expired, licenseExpiringSoon: expiring, licenseValidationStatus: expired ? 'EXPIRED' : expiring ? 'EXPIRING' : 'VALID' } })
    }
  }
})

// Daily: send trial-ending reminders (3 days before trial end)
cron.schedule('0 9 * * *', async () => {
  const soon = new Date(Date.now() + 3 * 24 * 60 * 60 * 1000)
  const subscriptions = await prisma.subscription.findMany({
    where: { status: 'TRIALING', trialEndAt: { lte: soon, gte: new Date() } },
    include: { company: { include: { employees: { where: { role: 'OWNER' } } } } },
  })
  for (const sub of subscriptions) {
    const owner = sub.company.employees[0]
    if (owner) {
      await prisma.notification.create({
        data: { type: 'SUBSCRIPTION_TRIAL_ENDING', title: 'Your trial ends soon', body: 'Your 14-day free trial ends in 3 days. Add a payment method to keep access.', companyId: sub.companyId, employeeId: owner.id, channel: 'IN_APP', status: 'DELIVERED' },
      })
    }
  }
})

// ─── Start ────────────────────────────────────────────────────
const PORT = process.env.API_PORT ?? 4000
server.listen(PORT, () => {
  console.log(`[API] Server running on port ${PORT}`)
})

export { app, io }