<script>
function with_iframe(url) {
  return new Promise(resolve => {
    let frame = document.createElement('iframe');
    frame.src = url;
    frame.onload = () => { resolve(frame); };
    document.body.appendChild(frame);
  });
}

function with_sandboxed_iframe(url, sandbox) {
  return new Promise(resolve => {
    let frame = document.createElement('iframe');
    frame.sandbox = sandbox;
    frame.src = url;
    frame.onload = () => { resolve(frame); };
    document.body.appendChild(frame);
  });
}

function fetch_from_worker(url) {
  return new Promise(resolve => {
    let blob = new Blob([
      `fetch('${url}', {mode: 'no-cors'})` +
      "  .then(() => { self.postMessage('OK'); });"]);
    let worker_url = URL.createObjectURL(blob);
    let worker = new Worker(worker_url);
    worker.onmessage = resolve;
  });
}

function run_test(type) {
  const base_path = location.href;
  switch (type) {
    case 'fetch':
      return fetch(`${base_path}&test=fetch`, {mode: 'no-cors'});
    case 'fetch-from-worker':
      return fetch_from_worker(`${base_path}&test=fetch-from-worker`);
    case 'iframe':
      return with_iframe(`${base_path}&test=iframe`);
    case 'sandboxed-iframe':
      return with_sandboxed_iframe(`${base_path}&test=sandboxed-iframe`,
                                   "allow-scripts");
    case 'sandboxed-iframe-same-origin':
      return with_sandboxed_iframe(
        `${base_path}&test=sandboxed-iframe-same-origin`,
        "allow-scripts allow-same-origin");
    default:
      return Promise.reject(`Unknown type: ${type}`);
  }
}

window.onmessage = event => {
  let id = event.data['id'];
  run_test(event.data['type'])
    .then(() => {
      window.top.postMessage({id: id, result: 'done'}, '*');
    })
    .catch(e => {
      window.top.postMessage({id: id, result: 'error: ' + e.toString()}, '*');
    });
};
</script>