/**
 * Express API Server
 * @author Descomplicar® | @link descomplicar.pt | @copyright 2026
 */
import 'dotenv/config'
import express from 'express'
import cors from 'cors'
import rateLimit from 'express-rate-limit'
import path from 'path'
import { fileURLToPath } from 'url'
import crypto from 'crypto'
import dashboardRouter from './routes/dashboard.js'
import monitorRouter from './routes/monitor.js'
import diagnosticRouter from './routes/diagnostic.js'
import hetznerRouter from './routes/hetzner.js'
import wpMonitorRouter from './routes/wp-monitor.js'
import serverMetricsRouter from './routes/server-metrics.js'
import financialRouter from './routes/financial.js'
import { collectAllServerMetrics } from './services/server-metrics.js'
import { collectMonitoringData } from './services/monitoring-collector.js'

const __filename = fileURLToPath(import.meta.url)
const __dirname = path.dirname(__filename)

const app = express()
const PORT = process.env.API_PORT || 3001
const isProduction = process.env.NODE_ENV === 'production'

// ============================================================================
// SECURITY: Rate Limiting (Vulnerabilidade 2.1)
// ============================================================================
const limiter = rateLimit({
  windowMs: 15 * 60 * 1000, // 15 minutos
  max: isProduction ? 100 : 1000, // 100 requests em produção, 1000 em dev
  message: { error: 'Too many requests from this IP, please try again later.' },
  standardHeaders: true,
  legacyHeaders: false,
})

app.use('/api', limiter)

// ============================================================================
// SECURITY: CORS Restrito (Vulnerabilidade 2.2)
// ============================================================================
const allowedOrigins = [
  'https://dash.descomplicar.pt',
  'https://dashboard.descomplicar.pt',
  'https://desk.descomplicar.pt'
]

// Em desenvolvimento, adicionar localhost
if (!isProduction) {
  allowedOrigins.push('http://localhost:5173')
  allowedOrigins.push('http://localhost:3050')
  allowedOrigins.push(process.env.FRONTEND_URL || 'http://localhost:5173')
}

const corsMiddleware = cors({
  origin: (origin, callback) => {
    // Permitir requests sem origin (curl, Postman, etc) em dev
    if (!origin && !isProduction) {
      return callback(null, true)
    }

    if (!origin || allowedOrigins.includes(origin)) {
      callback(null, true)
    } else {
      console.warn(`[SECURITY] Blocked CORS request from: ${origin}`)
      callback(new Error('Not allowed by CORS'))
    }
  },
  credentials: true
})

// CORS apenas nas rotas API (nao bloquear assets estaticos)
app.use('/api', corsMiddleware)

app.use(express.json())

// ============================================================================
// SECURITY: Autenticação Backend (Vulnerabilidade 2.5) - OPCIONAL
// ============================================================================
// Se OIDC_ENABLED=true e OIDC_SECRET definido, ativa autenticação
// Caso contrário, APIs ficam sem autenticação (para compatibilidade)
const oidcEnabled = process.env.OIDC_ENABLED === 'true' && process.env.OIDC_SECRET

if (oidcEnabled) {
  console.log('[SECURITY] OIDC authentication enabled for API routes')

  // Middleware simples de verificação de token
  // Para implementação completa, usar express-openid-connect
  app.use('/api', (req, res, next) => {
    const authHeader = req.headers.authorization

    if (!authHeader || !authHeader.startsWith('Bearer ')) {
      return res.status(401).json({ error: 'Unauthorized', message: 'Missing or invalid token' })
    }

    // Aqui deveria validar o JWT token com a OIDC authority
    // Por agora, aceitar qualquer token (placeholder para implementação futura)
    next()
  })
} else {
  console.warn('[SECURITY] API routes are NOT protected by authentication (set OIDC_ENABLED=true to enable)')
}

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

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

// Routes
app.use('/api/dashboard', dashboardRouter)
app.use('/api/monitor', monitorRouter)
app.use('/api/diagnostic', diagnosticRouter)
app.use('/api/hetzner', hetznerRouter)
app.use('/api/wp-monitor', wpMonitorRouter)
app.use('/api/server-metrics', serverMetricsRouter)
app.use('/api/financial', financialRouter)

// Serve static files in production
if (isProduction) {
  // __dirname is /app/api/dist, need to go up 2 levels to /app/dist
  const distPath = path.join(__dirname, '..', '..', 'dist')
  app.use(express.static(distPath))

  // SPA fallback - serve index.html for all non-API routes
  app.get('*', (req, res, next) => {
    if (req.path.startsWith('/api')) {
      return next()
    }
    res.sendFile(path.join(distPath, 'index.html'))
  })
}

// ============================================================================
// SECURITY: Error Handling Melhorado (Vulnerabilidade 2.5)
// ============================================================================
app.use((err: any, req: express.Request, res: express.Response, _next: express.NextFunction) => {
  const errorId = crypto.randomUUID()

  // Log estruturado sem stack trace em produção
  if (isProduction) {
    console.error(JSON.stringify({
      errorId,
      message: err.message,
      path: req.path,
      method: req.method,
      timestamp: new Date().toISOString()
    }))
  } else {
    console.error('Server error:', err)
  }

  // Resposta genérica ao cliente
  res.status(err.status || 500).json({
    error: isProduction ? 'Internal server error' : err.message,
    errorId
  })
})

// Start server
app.listen(PORT, () => {
  if (!isProduction) {
    console.log('='.repeat(50))
    console.log(`API Server running on http://localhost:${PORT}`)
    console.log(`Dashboard: http://localhost:${PORT}/api/dashboard`)
    console.log(`Monitor: http://localhost:${PORT}/api/monitor`)
    console.log(`Hetzner: http://localhost:${PORT}/api/hetzner`)
    console.log('='.repeat(50))
  }

  // Auto-collect metrics every 5 minutes
  if (isProduction) {
    const INTERVAL = 5 * 60 * 1000
    console.log('[SCHEDULER] Server metrics + monitoring collection every 5min')

    // Initial collection after 30s (let server stabilize)
    setTimeout(() => {
      collectAllServerMetrics().catch(err =>
        console.error('[SCHEDULER] Initial server metrics failed:', err.message)
      )
      collectMonitoringData().catch(err =>
        console.error('[SCHEDULER] Initial monitoring collection failed:', err.message)
      )
    }, 30000)

    // Recurring collection
    setInterval(() => {
      collectAllServerMetrics().catch(err =>
        console.error('[SCHEDULER] Server metrics failed:', err.message)
      )
      collectMonitoringData().catch(err =>
        console.error('[SCHEDULER] Monitoring collection failed:', err.message)
      )
    }, INTERVAL)
  }
})