const express = require('express')
const axios = require('axios')

const port = 3456

// 起个服务
const app = express()
app.use(express.json())
app.use(express.urlencoded({ extended: true }))

// 允许跨域
app.use((req, res, next) => {
  res.header('Access-Control-Allow-Origin', '*') // 允许所有来源的跨域请求，或者指定一个域名
  res.header('Access-Control-Allow-Methods', '*') // 允许的方法
  res.header('Access-Control-Allow-Headers', '*') // 允许的头部信息
  next()
})

// 监听对话请求
app.get('/ai/test', (req, res) => {
  res
    .json({
      code: 0,
      data: null,
      msg: '连接成功'
    })
    .end()
})
app.post('/ai/chat', async (req, res, next) => {
  // 设置SSE响应头
  res.setHeader('Content-Type', 'text/event-stream')
  res.setHeader('Cache-Control', 'no-cache')
  res.setHeader('Connection', 'keep-alive')

  const { api, method = 'POST', headers = {}, data } = req.body

  try {
    const response = await axios({
      url: api,
      method,
      headers,
      data,
      responseType: 'stream'
    })
    response.data.pipe(res)
  } catch (error) {
    next(error)
  }
})

app.listen(port, () => {
  console.log(`app listening on port ${port}`)
})