const express = require('express');
const { createProxyMiddleware } = require('http-proxy-middleware');
const { spawn } = require('child_process');

const proxyPort = 3000;
const nextPort = 3001;
const goBackendPort = 9999;

// 启动 Next.js 开发服务器
function startNextServer() {
  return new Promise((resolve, reject) => {
    console.log(`Starting Next.js server on port ${nextPort}...`);
    
    if (process.platform === 'win32') {
      // Windows 平台下，使用cmd拉起npx
      nextProcess = spawn('cmd.exe', ['/c', 'npx', 'next', 'dev', '-p', nextPort.toString()], {
        stdio: 'pipe',
        env: { ...process.env }
      });
    } else {
      // 其他平台
      nextProcess = spawn('npx', ['next', 'dev', '-p', nextPort.toString()], {
        stdio: 'pipe',
        env: { ...process.env }
      });
    }

    nextProcess.stdout.on('data', (data) => {
      const output = data.toString();
      console.log(`[Next.js] ${output.trim()}`);
      
      // 检测 Next.js 是否已经启动完成
      if (output.includes('Ready') || output.includes('started server')) {
        resolve(nextProcess);
      }
    });

    nextProcess.stderr.on('data', (data) => {
      console.error(`[Next.js Error] ${data.toString().trim()}`);
    });

    nextProcess.on('error', (error) => {
      console.error('Failed to start Next.js server:', error);
      reject(error);
    });

    // 设置超时
    setTimeout(() => {
      resolve(nextProcess);
    }, 10000);
  });
}

// 启动 Express 代理服务器
async function startProxyServer() {
  console.log(`Starting Express proxy server on port ${proxyPort}...`);
  
  const app = express();

  // Socket.io 代理到 Go 后端
  const socketProxy = createProxyMiddleware('/socket.io', {
    target: `http://localhost:${goBackendPort}`,
    ws: true,
    changeOrigin: true,
    logLevel: 'debug'
  });

  // Next.js 代理
  const nextProxy = createProxyMiddleware({
    target: `http://localhost:${nextPort}`,
    changeOrigin: true,
    ws: true, // 支持 WebSocket（用于热重载）
    logLevel: 'silent'
  });

  // 添加代理中间件
  app.use('/socket.io', socketProxy);
  app.use('/', nextProxy);

  // app.on('upgrade', (req, socket, head) => {
  //   console.log('WebSocket upgrade request received');
  //   socketProxy(req, socket, head);
  // });

  app.listen(proxyPort, () => {
    console.log(`🚀 Proxy server ready on http://localhost:${proxyPort}`);
    console.log(`📡 Proxying Socket.io to http://localhost:${goBackendPort}`);
    console.log(`⚛️  Proxying Next.js from http://localhost:${nextPort}`);
  });
}

// 主启动函数
async function start() {
  try {
    // 先启动 Next.js 服务器
    const nextProcess = await startNextServer();
    
    // 等待一下确保 Next.js 完全启动
    await new Promise(resolve => setTimeout(resolve, 2000));
    
    // 然后启动代理服务器
    await startProxyServer();

    // 优雅关闭处理
    process.on('SIGINT', () => {
      console.log('\n🛑 Shutting down servers...');
      nextProcess.kill('SIGTERM');
      process.exit(0);
    });

    process.on('SIGTERM', () => {
      console.log('\n🛑 Shutting down servers...');
      nextProcess.kill('SIGTERM');
      process.exit(0);
    });

  } catch (error) {
    console.error('Failed to start servers:', error);
    process.exit(1);
  }
}

start();