// 简易静态服务器，根目录为 军政门户/
// 用法: node server.js [port]
const http = require('http');
const fs = require('fs');
const path = require('path');

const ROOT = path.resolve(__dirname);
const PORT = process.argv[2] || 8765;

const MIME = {
  '.html': 'text/html; charset=utf-8',
  '.css':  'text/css; charset=utf-8',
  '.js':   'application/javascript; charset=utf-8',
  '.jpg':  'image/jpeg',
  '.jpeg': 'image/jpeg',
  '.png':  'image/png',
  '.gif':  'image/gif',
  '.ico':  'image/x-icon',
  '.svg':  'image/svg+xml'
};

const server = http.createServer((req, res) => {
  let url = decodeURIComponent(req.url.split('?')[0]);
  if (url === '/') url = '/css/首页模板.html';
  const filePath = path.join(ROOT, url);

  // 防越界
  if (!filePath.startsWith(ROOT)) {
    res.writeHead(403); return res.end('Forbidden');
  }

  fs.stat(filePath, (err, stat) => {
    if (err || !stat.isFile()) {
      res.writeHead(404, { 'Content-Type': 'text/plain; charset=utf-8' });
      return res.end('404 Not Found: ' + url);
    }
    const ext = path.extname(filePath).toLowerCase();
    res.writeHead(200, { 'Content-Type': MIME[ext] || 'application/octet-stream' });
    fs.createReadStream(filePath).pipe(res);
  });
});

server.listen(PORT, '127.0.0.1', () => {
  console.log(`预览服务器已启动: http://localhost:${PORT}/`);
  console.log(`首页模板: http://localhost:${PORT}/preview.html`);
});