const WebSocket = require('ws');
const redis = require('redis');

// Конфигурация
const REDIS_HOST = process.env.REDIS_HOST || 'host.docker.internal';
const REDIS_PORT = process.env.REDIS_PORT || 6379;
const REDIS_PASSWORD = process.env.REDIS_PASSWORD || 'CRM_Redis_Pass_2025_Secure!';
const WS_PORT = process.env.WS_PORT || 3000;
const REDIS_CHANNEL = 'crm:file:events';

console.log('🚀 Starting CRM WebSocket Server...');
console.log(`📡 Redis: ${REDIS_HOST}:${REDIS_PORT}`);
console.log(`🔌 WebSocket: 0.0.0.0:${WS_PORT}`);
console.log(`📢 Channel: ${REDIS_CHANNEL}`);

// Создаем WebSocket сервер
const wss = new WebSocket.Server({ 
    port: WS_PORT,
    perMessageDeflate: false
});

// Подключаемся к Redis для Pub/Sub
const subscriber = redis.createClient({
    socket: {
        host: REDIS_HOST,
        port: REDIS_PORT
    },
    password: REDIS_PASSWORD
});

subscriber.on('error', (err) => {
    console.error('❌ Redis Subscriber Error:', err);
});

subscriber.on('connect', () => {
    console.log('✅ Redis Subscriber connected');
});

// Подключаемся и подписываемся на канал
(async () => {
    try {
        await subscriber.connect();
        await subscriber.subscribe(REDIS_CHANNEL, (message) => {
            console.log(`📨 Received from Redis: ${message.substring(0, 100)}...`);
            
            // Отправляем всем WebSocket клиентам
            let sentCount = 0;
            wss.clients.forEach((client) => {
                if (client.readyState === WebSocket.OPEN) {
                    client.send(message);
                    sentCount++;
                }
            });
            
            console.log(`📤 Sent to ${sentCount} WebSocket clients`);
        });
        
        console.log(`✅ Subscribed to Redis channel: ${REDIS_CHANNEL}`);
    } catch (err) {
        console.error('❌ Failed to connect to Redis:', err);
        process.exit(1);
    }
})();

// WebSocket сервер
wss.on('connection', (ws, req) => {
    const clientIp = req.socket.remoteAddress;
    console.log(`🔗 New WebSocket connection from ${clientIp}`);
    console.log(`👥 Total clients: ${wss.clients.size}`);
    
    // Отправляем приветственное сообщение
    ws.send(JSON.stringify({
        type: 'connected',
        data: {
            message: 'Connected to CRM WebSocket Server',
            channel: REDIS_CHANNEL,
            timestamp: Date.now()
        }
    }));
    
    // Heartbeat
    ws.isAlive = true;
    ws.on('pong', () => {
        ws.isAlive = true;
    });
    
    // Обработка сообщений от клиента
    ws.on('message', (message) => {
        console.log(`📩 Message from client: ${message}`);
        
        try {
            const data = JSON.parse(message);
            
            // Обработка ping
            if (data.type === 'ping') {
                ws.send(JSON.stringify({
                    type: 'pong',
                    timestamp: Date.now()
                }));
            }
        } catch (err) {
            console.error('❌ Invalid message format:', err);
        }
    });
    
    // Обработка закрытия соединения
    ws.on('close', (code, reason) => {
        console.log(`🔌 WebSocket disconnected: ${code} - ${reason}`);
        console.log(`👥 Total clients: ${wss.clients.size}`);
    });
    
    // Обработка ошибок
    ws.on('error', (err) => {
        console.error('❌ WebSocket error:', err);
    });
});

// Heartbeat для проверки живых соединений
const heartbeat = setInterval(() => {
    wss.clients.forEach((ws) => {
        if (ws.isAlive === false) {
            console.log('💔 Terminating dead connection');
            return ws.terminate();
        }
        
        ws.isAlive = false;
        ws.ping();
    });
}, 30000); // Каждые 30 секунд

// Обработка завершения
wss.on('close', () => {
    clearInterval(heartbeat);
    subscriber.quit();
    console.log('🛑 WebSocket server stopped');
});

// Обработка сигналов завершения
process.on('SIGTERM', () => {
    console.log('🛑 SIGTERM received, closing server...');
    wss.close(() => {
        subscriber.quit();
        process.exit(0);
    });
});

process.on('SIGINT', () => {
    console.log('🛑 SIGINT received, closing server...');
    wss.close(() => {
        subscriber.quit();
        process.exit(0);
    });
});

console.log('✅ WebSocket server started successfully!');
console.log(`🎯 Ready to receive events from Redis and broadcast to ${wss.clients.size} clients`);