<!DOCTYPE html>
<script src="/resources/testharness.js"></script>
<script src="utils.js"></script>
<title>Fenced frame content to report the value of window.top</title>

<body>
<script>
async function init() { // Needed in order to use top-level await.
  // This file is meant to run in a <fencedframe>. It reports back to the
  // outermost page whether or not the value of `window.top` was correct for:
  //   1.) Top-level fenced frames
  //   2.) Nested iframes inside a fenced frame
  //   3.) Nested fenced frames
  const url = new URL(location.href);

  const [window_top_key, window_top_ack_key, nested] = parseKeylist();

  // Report whether or not `window.top` was correct.
  let pass_string = "";
  if (nested == "nested")
    pass_string = "pass: fenced frame > fenced frame";
  else
    pass_string = "pass: fenced frame";

  let result = (window.top == window) ? pass_string : "fail";
  writeValueToServer(window_top_key, result);

  // If this page is a nested fenced frame, all we need to do is report the
  // top-level value.
  if (nested == "nested")
    return;

  // Wait for ACK, so we know that the outer page has read the last value from
  // the `window_top_key` stash and we can write to it again.
  await nextValueFromServer(window_top_ack_key);

  // Now test `window.top` inside an iframe.
  const iframe = document.createElement('iframe');
  iframe.src = "dummy.html";
  const load_promise = new Promise((resolve, reject) => {
    iframe.onload = resolve;
    iframe.onerror = reject;
  });
  document.body.append(iframe);

  await load_promise;

  // Report whether or not the subframe's `window.top` was correct.
  result = (iframe.contentWindow.top == window) ?
      "pass: fenced frame > iframe" : "fail";
  writeValueToServer(window_top_key, result);

  // Wait for ACK, so we know that the outer page has read the last value from
  // the `window_top_key` stash and we can write to it again.
  await nextValueFromServer(window_top_ack_key);

  attachFencedFrame(generateURL("window-top-inner.html",
      [window_top_key, window_top_ack_key, "nested"]));
}

init();
</script>
</body>
