server.js

// simple-chat/server.js
import express from 'express';
import http from 'http';
import { Server } from 'socket.io';

//=== Basic server ===
const app = express();
const server = http.createServer(app);
const io = new Server(server, { /* options (e.g., cors) can be added here */ });

// Serve the single static HTML page
app.get('/', (_req, res) => {
  res.sendFile(`${process.cwd()}/index.html`);
});

// In‑memory chat history (last 100 messages)
const history = [];

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

  // Send existing history
  socket.emit('history', history);

  // Broadcast new messages
  socket.on('message', msg => {
    const data = {
      id: Date.now(),
      user: socket.id,
      text: msg,
      time: new Date().toISOString()
    };
    history.push(data);
    if (history.length > 100) history.shift(); // keep size
    io.emit('message', data);
  });

  socket.on('disconnect', () => console.log(`Disconnected: ${socket.id}`));
});

//=== Start ===
const PORT = process.env.PORT || 3000;
server.listen(PORT, () => console.log(`❶ Running on http://localhost:${PORT}`));