import 'dotenv/config';
import express from 'express';
import cors from 'cors';
import helmet from 'helmet';
import compression from 'compression';
import rateLimit from 'express-rate-limit';
import { createServer } from 'http';
import { Server as SocketServer } from 'socket.io';
import { testConnection } from './db/pool';
import { logger } from './lib/logger';
import authRoutes from './routes/auth';
import herdRoutes from './routes/herd';
import breedRoutes from './routes/breed';
import marketRoutes from './routes/market';
import eventsRoutes from './routes/events';
import ranchRoutes from './routes/ranch';

const app = express();
const httpServer = createServer(app);

app.use(express.json());
app.use(express.urlencoded({ extended: true }));

// ─── Socket.IO for real-time features ────────────────────────────────────────

const io = new SocketServer(httpServer, {
  cors: {
    origin: process.env.CLIENT_URL || 'http://localhost:5173',
    methods: ['GET', 'POST'],
    credentials: true,
  },
});

io.on('connection', (socket) => {
  logger.debug(`Socket connected: ${socket.id}`);

  socket.on('join:auction', (listingId: string) => {
    socket.join(`auction:${listingId}`);
  });

  socket.on('join:club', (clubId: string) => {
    socket.join(`club:${clubId}`);
  });

  socket.on('disconnect', () => {
    logger.debug(`Socket disconnected: ${socket.id}`);
  });
});

export { io };

// ─── Middleware ───────────────────────────────────────────────────────────────

app.use(helmet({
  crossOriginResourcePolicy: { policy: 'cross-origin' },
}));

app.use(cors({
  origin: process.env.CLIENT_URL || 'http://localhost:5173',
  credentials: true,
  methods: ['GET', 'POST', 'PUT', 'PATCH', 'DELETE', 'OPTIONS'],
}));

app.use(compression());
app.use(express.json({ limit: '1mb' }));
app.use(express.urlencoded({ extended: true }));

// General rate limiter
app.use(rateLimit({
  windowMs: parseInt(process.env.RATE_LIMIT_WINDOW_MS || '60000'),
  max: parseInt(process.env.RATE_LIMIT_MAX || '300'),
  standardHeaders: true,
  legacyHeaders: false,
  message: { error: 'RATE_LIMITED', message: 'Too many requests. Please slow down.' },
}));

// Strict limiter for auth endpoints
const authLimiter = rateLimit({
  windowMs: 15 * 60 * 1000,
  max: 10,
  message: { error: 'RATE_LIMITED', message: 'Too many auth attempts. Try again in 15 minutes.' },
});

// ─── Request logging ──────────────────────────────────────────────────────────

app.use((req, res, next) => {
  const start = Date.now();
  res.on('finish', () => {
    const duration = Date.now() - start;
    if (res.statusCode >= 400) {
      logger.warn(`${req.method} ${req.path} ${res.statusCode} ${duration}ms`);
    } else {
      logger.debug(`${req.method} ${req.path} ${res.statusCode} ${duration}ms`);
    }
  });
  next();
});

// ─── Routes ───────────────────────────────────────────────────────────────────

app.use('/api/v1/auth', authLimiter, authRoutes);
app.use('/api/v1/herd', herdRoutes);
app.use('/api/v1/breed', breedRoutes);
app.use('/api/v1/market', marketRoutes);
app.use('/api/v1/events', eventsRoutes);
app.use('/api/v1/ranch', ranchRoutes);

// ─── Health check ─────────────────────────────────────────────────────────────

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

// ─── 404 handler ──────────────────────────────────────────────────────────────

app.use((req, res) => {
  res.status(404).json({ error: 'NOT_FOUND', message: `Route ${req.method} ${req.path} not found` });
});

// ─── Error handler ────────────────────────────────────────────────────────────

app.use((err: any, req: express.Request, res: express.Response, next: express.NextFunction) => {
  logger.error('Unhandled error', err);
  res.status(500).json({ error: 'INTERNAL_ERROR', message: 'An unexpected error occurred' });
});

// ─── Start ────────────────────────────────────────────────────────────────────

const PORT = parseInt(process.env.PORT || '8584');

async function start() {
  try {
    await testConnection();
    httpServer.listen(PORT, () => {
      logger.info(`🐄 Ranchlands server running on port ${PORT}`);
      logger.info(`Environment: ${process.env.NODE_ENV || 'development'}`);
    });
  } catch (err) {
    logger.error('Failed to start server', err);
    process.exit(1);
  }
}

start();

export default app;