const http = require('http');
const crypto = require('crypto');
const { exec } = require('child_process');

// 配置 - 复制此文件为 webhook-handler.js 并修改配置
const PORT = 9000;
const SECRET = 'your_webhook_secret_change_this'; // 与 Gitea 中配置的密钥一致
const DEPLOY_SCRIPT = '/var/www/pixel-game-server/deploy.sh'; // 修改为实际路径

// 验证 Gitea 签名
function verifySignature(payload, signature, secret) {
  const hmac = crypto.createHmac('sha256', secret);
  hmac.update(payload);
  const calculatedSignature = hmac.digest('hex');
  return crypto.timingSafeEqual(
    Buffer.from(signature, 'hex'),
    Buffer.from(calculatedSignature, 'hex')
  );
}

// 创建 HTTP 服务器
const server = http.createServer((req, res) => {
  if (req.method !== 'POST') {
    res.writeHead(405, { 'Content-Type': 'text/plain' });
    res.end('Method Not Allowed');
    return;
  }

  let body = '';
  req.on('data', chunk => {
    body += chunk.toString();
  });

  req.on('end', () => {
    try {
      // 验证签名
      const signature = req.headers['x-gitea-signature'];
      if (!signature || !verifySignature(body, signature.replace('sha256=', ''), SECRET)) {
        console.log('签名验证失败');
        res.writeHead(401, { 'Content-Type': 'text/plain' });
        res.end('Unauthorized');
        return;
      }

      const payload = JSON.parse(body);
      
      // 检查是否是推送到 main 分支
      if (payload.ref === 'refs/heads/main') {
        console.log('收到 main 分支推送，开始部署...');
        
        // 执行部署脚本
        exec(`bash ${DEPLOY_SCRIPT}`, (error, stdout, stderr) => {
          if (error) {
            console.error('部署失败:', error);
            console.error('stderr:', stderr);
          } else {
            console.log('部署成功:', stdout);
          }
        });

        res.writeHead(200, { 'Content-Type': 'text/plain' });
        res.end('Deployment triggered');
      } else {
        res.writeHead(200, { 'Content-Type': 'text/plain' });
        res.end('Not main branch, ignored');
      }
    } catch (error) {
      console.error('处理 webhook 失败:', error);
      res.writeHead(500, { 'Content-Type': 'text/plain' });
      res.end('Internal Server Error');
    }
  });
});

server.listen(PORT, () => {
  console.log(`Webhook 处理器运行在端口 ${PORT}`);
});

// 优雅关闭
process.on('SIGTERM', () => {
  console.log('收到 SIGTERM，正在关闭服务器...');
  server.close(() => {
    console.log('服务器已关闭');
    process.exit(0);
  });
});