const express = require('express');
const path = require('path');
const { spawn } = require('child_process');
const cors = require('cors');
const { parseK6StdoutTable, watchClient } = require("./utils");

const app = express();

const isDev = process.env.NODE_ENV === 'development';
const PORT = isDev ? 8080 : 9001;
const SCREENSHOTS_DIR = path.join(__dirname, 'screenshots');
const CLIENT_DIST_DIR = isDev ? path.join(__dirname, '../client/dist') : path.join(__dirname, './public');

// 开发模式下监听client文件变动执行打包脚本
if (isDev) {
  watchClient()
}

// ====== 中间件 ======
app.use(cors());

// 静态资源
app.use('/static', express.static(SCREENSHOTS_DIR));
app.use(express.static(CLIENT_DIST_DIR));


// ====== API 路由 ======
app.get('/api/k6', async (req, res) => {
  const targetUrl = req.query.targetUrl;
  const timeStamp = req.query.timeStamp;
  console.log("targetUrl:", targetUrl);
  console.log("timeStamp:", timeStamp);

  if (!targetUrl || !timeStamp) {
    return res.status(400).json({ error: '缺少 targetUrl 或 timeStamp 参数' });
  }

  // 运行 k6 脚本
  const k6Process = spawn('k6', ['run', '--no-color=false', '--env', 'targetUrl=' + targetUrl, '--env', 'timeStamp=' + timeStamp, './script-browser.js']);

  let outputBuffer = '';
  k6Process.stdout.on('data', (chunk) => {
    outputBuffer += chunk.toString();
    console.log(chunk.toString())
  });

  k6Process.on('close', () => {
    const parsed = parseK6StdoutTable(outputBuffer);
    res.json(parsed); // 返回结构化结果给前端
  });
});

// ====== history 路由兼容（放在所有 API 路由之后） ======
app.get('*', (req, res) => {
  res.sendFile(path.join(CLIENT_DIST_DIR, 'index.html'));
});

// ====== 启动服务 ======
app.listen(PORT, () => {
  console.log(`Express server running at http://localhost:${PORT}`);
});