<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<script type="application/javascript">
"use strict";

window.onload = () => {
  opener.postMessage("ready", "*");
};

// eslint-disable-next-line no-shadow
function promiseMessage(source, filter = event => true) {
  return new Promise(resolve => {
    function listener(event) {
      if (event.source == source && filter(event)) {
        removeEventListener("message", listener);
        resolve(event);
      }
    }
    addEventListener("message", listener);
  });
}

// Sends a message to the given target window and waits for the response.
function ping(target) {
  let msg = { ping: Math.random() };
  target.postMessage(msg, "*");
  return promiseMessage(
    target,
    event => event.data && event.data.pong == msg.ping
  );
}

function setFrameLocation(name, uri) {
  window[name].location = uri;
}
</script>
</head>
<body>
</body>
</html>
