server.js

const { log } = require('console');
const express = require('express');
const http = require('http');
const { Server } = require('socket.io');

const app = express();
const server = http.createServer(app);
const io = new Server(server);
const PORT = process.env.PORT || 3000;

const users = {};

app.use(express.static('public'));

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

  socket.on('joinRoom', ({ nickname, room }) => {
    users[socket.id] = { nickname, room };
    socket.join(room);

    socket.emit('message', {
      nickname: 'Admin',
      text: `Welcome to the room ${room}, ${nickname}!`
    });

    io.to(room).emit('message', {
      nickname: 'Admin',
      text: `${nickname} has joined the room!`
    });

    console.log(`${nickname} (${socket.id}) joined room: ${room}`);
  });

  socket.on('chatMessage', (msg) => {
    const user = users[socket.id];
    if (user) {
      io.to(user.room).emit('message', {
        nickname: user.nickname,
        text: msg
      });
    }
  });

  socket.on('disconnect', () => {
    const user = users[socket.id];
    if (user) {
      io.to(user.room).emit('message', {
        nickname: 'System',
        text: `${user.nickname} has left the room.`
      });
      console.log(`${user.nickname} (${socket.id}) disconnected.`);
      delete users[socket.id];
    }
  });
});

server.listen(PORT, () => {
  console.log(`Server is running on http://localhost:${PORT}`);
});