import test from 'brittle'
import net from 'node:net'
import {
  bindFallbackEnabled,
  isAddrInUse,
  listenTcpWithFallback,
  readListeningTcpPort,
  BARE_OS_BIND_FALLBACK_ENV
} from './lib/posix/bare-os-bind-fallback.js'

test('bindFallbackEnabled', (t) => {
  t.ok(bindFallbackEnabled({}))
  t.ok(bindFallbackEnabled({ [BARE_OS_BIND_FALLBACK_ENV]: '1' }))
  t.absent(bindFallbackEnabled({ [BARE_OS_BIND_FALLBACK_ENV]: '0' }))
  t.absent(bindFallbackEnabled({ [BARE_OS_BIND_FALLBACK_ENV]: 'false' }))
})

test('isAddrInUse', (t) => {
  t.ok(isAddrInUse(Object.assign(new Error('x'), { code: 'EADDRINUSE' })))
  t.absent(isAddrInUse(Object.assign(new Error('x'), { code: 'ENOENT' })))
  t.ok(isAddrInUse(new Error('listen EADDRINUSE: address already in use')))
})

test('listenTcpWithFallback picks ephemeral when preferred port busy', async (t) => {
  const hog = net.createServer()
  await new Promise((resolve, reject) => {
    hog.once('error', reject)
    hog.listen(0, '127.0.0.1', resolve)
  })
  const hogPort = readListeningTcpPort(hog, 0)
  t.ok(Number.isFinite(hogPort) && hogPort > 0)

  const srv = net.createServer()
  const { port } = await listenTcpWithFallback(
    srv,
    hogPort,
    '127.0.0.1',
    {}
  )
  t.not(port, hogPort)
  t.ok(port > 0)

  await new Promise((resolve) => srv.close(resolve))
  await new Promise((resolve) => hog.close(resolve))
})

test('listenTcpWithFallback strict env rethrows EADDRINUSE', async (t) => {
  const hog = net.createServer()
  await new Promise((resolve, reject) => {
    hog.once('error', reject)
    hog.listen(0, '127.0.0.1', resolve)
  })
  const hogPort = readListeningTcpPort(hog, 0)

  const srv = net.createServer()
  try {
    await listenTcpWithFallback(srv, hogPort, '127.0.0.1', {
      [BARE_OS_BIND_FALLBACK_ENV]: '0'
    })
    t.fail('expected EADDRINUSE')
  } catch (e) {
    t.ok(isAddrInUse(e))
  }

  await new Promise((resolve) => hog.close(resolve))
})