const { Server: SocketIOServer } = require('socket.io');
const { Server: HTTPServer } = require('http');

// Store active connections
const activeUsers = new Map();

function createSocketService(httpServer) {
  const io = new SocketIOServer(httpServer, {
    cors: {
      origin: '*',
      methods: ['GET', 'POST']
    }
  });

  io.on('connection', (socket) => {
    console.log(`New client connected: ${socket.id}`);

    // Handle user login/registration
    socket.on('user:register', (userId) => {
      console.log(`User registered: ${userId} (Socket: ${socket.id})`);
      activeUsers.set(userId, socket.id);
      // Broadcast updated user list
      io.emit('users:update', Array.from(activeUsers.keys()));
    });

    // Handle location updates
    socket.on('location:update', (data) => {
      console.log(`Location update from ${data.userId}: ${data.latitude}, ${data.longitude}`);
      // Broadcast to all connected clients
      io.emit('location:broadcast', data);
    });

    // Handle direct messages or location shares
    socket.on('location:share', (data) => {
      console.log(`Location share from ${data.fromUserId} to ${data.toUserId}`);
      const targetSocketId = activeUsers.get(data.toUserId);
      
      if (targetSocketId) {
        // Send to specific user
        io.to(targetSocketId).emit('location:shared', {
          fromUserId: data.fromUserId,
          latitude: data.latitude,
          longitude: data.longitude
        });
      }
    });

    // Handle disconnect
    socket.on('disconnect', () => {
      console.log(`Client disconnected: ${socket.id}`);
      // Remove user from active users
      for (const [userId, socketId] of activeUsers.entries()) {
        if (socketId === socket.id) {
          activeUsers.delete(userId);
          break;
        }
      }
      // Broadcast updated user list
      io.emit('users:update', Array.from(activeUsers.keys()));
    });
  });

  return io;
}

module.exports = createSocketService;