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

const PORT = 4155;
const HOST = '0.0.0.0';

// MIME 类型映射
const mimeTypes = {
  '.html': 'text/html; charset=utf-8',
  '.css': 'text/css',
  '.js': 'text/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',
  '.eot': 'font/eot'
};

// 创建服务器
const server = http.createServer((req, res) => {
  // 记录请求
  const timestamp = new Date().toLocaleString('zh-CN');
  const clientIP = req.connection.remoteAddress || req.socket.remoteAddress;
  console.log(`[${timestamp}] ${clientIP} -> ${req.method} ${req.url}`);
  
  // 解析 URL
  const parsedUrl = url.parse(req.url);
  let pathname = decodeURIComponent(parsedUrl.pathname);
  
  // 默认文件
  if (pathname === '/') {
    pathname = '/index.html';
  }
  
  // 构建文件路径
  const filePath = path.join(__dirname, pathname);
  
  // 安全检查：确保文件路径在当前目录内
  if (!filePath.startsWith(__dirname)) {
    res.writeHead(403);
    res.end('Forbidden');
    return;
  }
  
  // 检查文件是否存在
  fs.stat(filePath, (err, stats) => {
    if (err) {
      // 文件不存在
      res.writeHead(404);
      res.end('Not Found');
      return;
    }
    
    if (stats.isDirectory()) {
      // 如果是目录，尝试加载 index.html
      const indexPath = path.join(filePath, 'index.html');
      fs.stat(indexPath, (err, stats) => {
        if (err) {
          res.writeHead(404);
          res.end('Not Found');
          return;
        }
        serveFile(indexPath, res);
      });
    } else {
      // 提供文件
      serveFile(filePath, res);
    }
  });
});

// 提供文件的函数
function serveFile(filePath, res) {
  const ext = path.extname(filePath);
  const contentType = mimeTypes[ext] || 'application/octet-stream';
  
  fs.readFile(filePath, (err, content) => {
    if (err) {
      res.writeHead(500);
      res.end('Internal Server Error');
      return;
    }
    
    res.writeHead(200, { 'Content-Type': contentType });
    res.end(content);
  });
}

// 获取本地IP地址
function getLocalIP() {
  const os = require('os');
  const interfaces = os.networkInterfaces();
  
  for (const name of Object.keys(interfaces)) {
    for (const iface of interfaces[name]) {
      // 跳过内部（即127.0.0.1）和非IPv4地址
      if (iface.family === 'IPv4' && !iface.internal) {
        return iface.address;
      }
    }
  }
  return 'localhost';
}

// 启动服务器
server.listen(PORT, HOST, () => {
  const localIP = getLocalIP();
  
  console.log('======================================');
  console.log('    Web Result 静态服务器启动成功');
  console.log('======================================');
  console.log('');
  console.log('🏠 本地访问:');
  console.log(`   http://localhost:${PORT}`);
  console.log('');
  
  if (localIP !== 'localhost') {
    console.log('🌐 局域网访问:');
    console.log(`   http://${localIP}:${PORT}`);
    console.log('');
    console.log('📱 移动设备访问:');
    console.log(`   http://${localIP}:${PORT}`);
    console.log('');
  }
  
  console.log('[提示] 服务器监听所有网络接口 (0.0.0.0)');
  console.log('[提示] 按 Ctrl+C 停止服务器');
  console.log('');
  console.log('等待请求...');
});