// Test helper: start a throwaway Express app on an ephemeral port and return its
// base URL + a close(). Uses the built-in fetch (Node 18+) so tests need no
// extra HTTP dependency. Tests here exercise middleware in isolation and do NOT
// touch the database.
const express = require('express')

async function startApp(configure) {
  const app = express()
  app.use(express.json())
  configure(app)
  const server = await new Promise((resolve) => {
    const s = app.listen(0, '127.0.0.1', () => resolve(s))
  })
  const { port } = server.address()
  return {
    url: `http://127.0.0.1:${port}`,
    // `server.close()` stops accepting and waits for open connections to end on
    // their own — and node's global fetch keeps its sockets alive, so nothing
    // ever ends them. The listener then outlives the test that made it, which
    // used to be invisible because the pool held the process open anyway.
    close: () => new Promise((resolve) => {
      server.closeAllConnections()
      server.close(resolve)
    }),
  }
}

module.exports = { startApp }