Class_generator/server.js

/**
 * Development Server - Simple HTTP server for local development
 * Handles static files, CORS, and development features
 */

import { createServer } from 'http';
import { readFile, stat } from 'fs/promises';
import { join, extname } from 'path';
import { fileURLToPath } from 'url';
import { dirname } from 'path';

const __filename = fileURLToPath(import.meta.url);
const __dirname = dirname(__filename);

const PORT = process.env.PORT || 3000;
const HOST = process.env.HOST || 'localhost';

// MIME types for different file extensions
const MIME_TYPES = {
    '.html': 'text/html',
    '.css': 'text/css',
    '.js': 'application/javascript',
    '.json': 'application/json',
    '.png': 'image/png',
    '.jpg': 'image/jpeg',
    '.jpeg': 'image/jpeg',
    '.gif': 'image/gif',
    '.svg': 'image/svg+xml',
    '.ico': 'image/x-icon',
    '.woff': 'font/woff',
    '.woff2': 'font/woff2',
    '.ttf': 'font/ttf',
    '.mp3': 'audio/mpeg',
    '.wav': 'audio/wav',
    '.mp4': 'video/mp4'
};

const server = createServer(async (req, res) => {
    try {
        // Parse URL and remove query parameters
        const urlPath = new URL(req.url, `http://${req.headers.host}`).pathname;

        // Default to index.html for root requests
        const filePath = urlPath === '/' ? 'index.html' : urlPath.slice(1);
        const fullPath = join(__dirname, filePath);

        console.log(`${new Date().toISOString()} - ${req.method} ${urlPath}`);

        // Set CORS headers for all requests
        res.setHeader('Access-Control-Allow-Origin', '*');
        res.setHeader('Access-Control-Allow-Methods', 'GET, POST, PUT, DELETE, OPTIONS');
        res.setHeader('Access-Control-Allow-Headers', 'Content-Type, Authorization');

        // Handle preflight requests
        if (req.method === 'OPTIONS') {
            res.writeHead(200);
            res.end();
            return;
        }

        // Check if file exists
        try {
            const stats = await stat(fullPath);

            if (stats.isDirectory()) {
                // Try to serve index.html from directory
                const indexPath = join(fullPath, 'index.html');
                try {
                    await stat(indexPath);
                    return serveFile(indexPath, res);
                } catch {
                    return send404(res, `Directory listing not allowed for ${urlPath}`);
                }
            }

            return serveFile(fullPath, res);

        } catch (error) {
            if (error.code === 'ENOENT') {
                return send404(res, `File not found: ${urlPath}`);
            }
            throw error;
        }

    } catch (error) {
        console.error('Server error:', error);

        res.writeHead(500, { 'Content-Type': 'text/plain' });
        res.end('Internal Server Error');
    }
});

async function serveFile(filePath, res) {
    try {
        const ext = extname(filePath).toLowerCase();
        const mimeType = MIME_TYPES[ext] || 'application/octet-stream';

        // Set content type
        res.setHeader('Content-Type', mimeType);

        // Set cache headers for static assets
        if (['.css', '.js', '.png', '.jpg', '.gif', '.svg', '.ico', '.woff', '.woff2'].includes(ext)) {
            res.setHeader('Cache-Control', 'public, max-age=3600'); // 1 hour
        } else {
            res.setHeader('Cache-Control', 'no-cache'); // No cache for HTML and other files
        }

        // Add security headers
        if (ext === '.js') {
            res.setHeader('X-Content-Type-Options', 'nosniff');
        }

        // Read and serve file
        const content = await readFile(filePath);

        res.writeHead(200);
        res.end(content);

        console.log(`  ✅ Served ${filePath} (${content.length} bytes, ${mimeType})`);

    } catch (error) {
        console.error(`Error serving file ${filePath}:`, error);

        res.writeHead(500, { 'Content-Type': 'text/plain' });
        res.end('Error reading file');
    }
}

function send404(res, message = 'Not Found') {
    const html404 = `
        <!DOCTYPE html>
        <html>
        <head>
            <title>404 - Not Found</title>
            <style>
                body {
                    font-family: Arial, sans-serif;
                    text-align: center;
                    padding: 2rem;
                    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
                    color: white;
                    min-height: 100vh;
                    display: flex;
                    flex-direction: column;
                    justify-content: center;
                }
                h1 { font-size: 3rem; margin-bottom: 1rem; }
                p { font-size: 1.2rem; opacity: 0.8; }
                a { color: white; text-decoration: underline; }
            </style>
        </head>
        <body>
            <h1>404</h1>
            <p>${message}</p>
            <p><a href="/">← Back to Class Generator</a></p>
        </body>
        </html>
    `;

    res.writeHead(404, { 'Content-Type': 'text/html' });
    res.end(html404);

    console.log(`  ❌ 404: ${message}`);
}

// Start server
server.listen(PORT, HOST, () => {
    console.log('\n🚀 Class Generator Development Server');
    console.log('=====================================');
    console.log(`📍 Local:    http://${HOST}:${PORT}/`);
    console.log(`🌐 Network:  http://localhost:${PORT}/`);
    console.log('📁 Serving files from:', __dirname);
    console.log('\n✨ Features:');
    console.log('   • ES6 modules support');
    console.log('   • CORS enabled');
    console.log('   • Static file serving');
    console.log('   • Development-friendly caching');
    console.log('\n🔥 Ready for development!');
    console.log('Press Ctrl+C to stop\n');
});

// Graceful shutdown
process.on('SIGINT', () => {
    console.log('\n👋 Shutting down server...');
    server.close(() => {
        console.log('✅ Server stopped');
        process.exit(0);
    });
});

process.on('SIGTERM', () => {
    console.log('\n👋 Received SIGTERM, shutting down...');
    server.close(() => {
        console.log('✅ Server stopped');
        process.exit(0);
    });
});