server.js

const http = require('http');
const fs = require('fs');
const path = require('path');

const server = http.createServer((req, res) => {
  if (req.url === '/' || req.url === '/index.html') {
    fs.readFile('demo-form.html', (err, data) => {
      if (err) {
        res.writeHead(500);
        res.end('Error loading demo form');
        return;
      }
      res.writeHead(200, { 'Content-Type': 'text/html' });
      res.end(data);
    });
  } else {
    res.writeHead(404);
    res.end('Not found');
  }
});

const PORT = 3000;
server.listen(PORT, () => {
  console.log(`Demo server running at http://localhost:${PORT}`);
  console.log('Press Ctrl+C to stop the server');
});

server.on('error', (err) => {
  if (err.code === 'EADDRINUSE') {
    console.log(`Port ${PORT} is already in use. Trying port ${PORT + 1}`);
    server.listen(PORT + 1);
  } else {
    console.error('Server error:', err);
  }
});