import express from 'express';
import cors from 'cors';
import helmet from 'helmet';
import compression from 'compression';
import { createServer } from 'http';
import { Server } from 'socket.io';
import dotenv from 'dotenv';
import { Logger } from './utils/logger';
import { NowhereCore } from './core/nowhere';
import { setupRoutes } from './routes';
import { setupWebSocket } from './websocket';
import { errorHandler } from './middleware/error-handler';
import { rateLimiter } from './middleware/rate-limiter';

// Load environment variables
dotenv.config();

const app = express();
const server = createServer(app);
const io = new Server(server, {
  cors: {
    origin: process.env.FRONTEND_URL || "*",
    methods: ["GET", "POST", "PUT", "DELETE"],
    credentials: true
  }
});

const logger = new Logger('Server');
const PORT = process.env.PORT || 3001;

// Initialize Nowhere Core
const nowhere = new NowhereCore();

// Security middleware
app.use(helmet({
  contentSecurityPolicy: {
    directives: {
      defaultSrc: ["'self'"],
      styleSrc: ["'self'", "'unsafe-inline'"],
      scriptSrc: ["'self'"],
      imgSrc: ["'self'", "data:", "https:"],
    },
  },
}));

// Compression middleware
app.use(compression());

// CORS middleware
app.use(cors({
  origin: process.env.FRONTEND_URL || "*",
  credentials: true,
  methods: ['GET', 'POST', 'PUT', 'DELETE', 'OPTIONS'],
  allowedHeaders: ['Content-Type', 'Authorization', 'X-Requested-With']
}));

// Body parsing middleware
app.use(express.json({ limit: '10mb' }));
app.use(express.urlencoded({ extended: true, limit: '10mb' }));

// Rate limiting
app.use(rateLimiter);

// Health check endpoint
app.get('/health', (req, res) => {
  res.json({
    status: 'ok',
    message: 'Nowhere AI Agent Backend is running',
    timestamp: new Date().toISOString(),
    version: '2.0.0',
    environment: process.env.NODE_ENV || 'development'
  });
});

// Setup API routes
setupRoutes(app, nowhere);

// Setup WebSocket
setupWebSocket(io, nowhere);

// Error handling middleware (must be last)
app.use(errorHandler);

// Graceful shutdown
process.on('SIGTERM', async () => {
  logger.info('SIGTERM received, shutting down gracefully');
  await nowhere.close();
  server.close(() => {
    logger.info('Server closed');
    process.exit(0);
  });
});

process.on('SIGINT', async () => {
  logger.info('SIGINT received, shutting down gracefully');
  await nowhere.close();
  server.close(() => {
    logger.info('Server closed');
    process.exit(0);
  });
});

// Start server
server.listen(PORT, () => {
  logger.info(`🚀 Nowhere AI Agent Backend running on port ${PORT}`);
  logger.info(`📊 Health check: http://localhost:${PORT}/health`);
  logger.info(`🔧 API status: http://localhost:${PORT}/api/v1/status`);
  logger.info(`💬 WebSocket: ws://localhost:${PORT}`);
  logger.info(`🌍 Environment: ${process.env.NODE_ENV || 'development'}`);
  
  // Log available features
  logger.info('✅ Features enabled:', {
    voiceCommands: true,
    autopilotMode: true,
    memorySystem: true,
    realTimeCommunication: true,
    advancedAIProcessing: true,
    multiModelSupport: true,
    security: true,
    logging: true
  });
});

// Handle uncaught exceptions
process.on('uncaughtException', (error) => {
  logger.error('Uncaught Exception', { error: error.message, stack: error.stack });
  process.exit(1);
});

process.on('unhandledRejection', (reason, promise) => {
  logger.error('Unhandled Rejection', { reason, promise });
  process.exit(1);
});

export { app, server, io, nowhere };