import http from 'node:http'

const prefix = '/extensions/qiu.subscription-admin'
const targetPort = Number(process.env.PLUGIN_TARGET_PORT || 18082)
const port = Number(process.env.MOCK_PROXY_PORT || 18081)

const server = http.createServer((req, res) => {
  if (!req.url.startsWith(prefix)) {
    res.writeHead(404)
    res.end('not found')
    return
  }
  const forwardedPath = req.url.slice(prefix.length) || '/'
  const proxy = http.request({ hostname: '127.0.0.1', port: targetPort, method: req.method, path: forwardedPath, headers: { ...req.headers, host: `127.0.0.1:${targetPort}` } }, (upstream) => {
    const headers = { ...upstream.headers }
    if (headers.location && headers.location.startsWith('/admin/')) headers.location = `${prefix}${headers.location}`
    res.writeHead(upstream.statusCode || 502, headers)
    upstream.pipe(res)
  })
  proxy.on('error', () => {
    if (!res.headersSent) res.writeHead(502)
    res.end('proxy error')
  })
  req.pipe(proxy)
})

server.listen(port, '127.0.0.1', () => process.stdout.write(`mock proxy listening on 127.0.0.1:${port}\n`))