<!DOCTYPE html>
<html class="reftest-wait">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Update subject bounds refTest</title>
<link rel="help" src="https://github.com/w3c/csswg-drafts/issues/8694">
<link rel="match"
      href="./animation-update-ref.html?translate=100px&scroll=800">
<script src="/web-animations/testcommon.js"></script>
</head>
<style type="text/css">
  @keyframes anim {
    from { transform: translateX(100px) }
    to { transform: translateX(0px) }
  }
  #scroller {
    border: 1px solid black;
    overflow: hidden;
    width: 300px;
    height: 200px;
  }
  #target {
    margin-bottom: 800px;
    margin-top: 700px;
    margin-left: 10px;
    margin-right: 10px;
    width: 100px;
    height: 200px;
    z-index: -1;
    background-color: green;
    animation: anim auto both linear;
    animation-timeline: --timeline;
    view-timeline: --timeline;
    animation-range: exit;
  }
  #target.bounds-update {
    height: 100px;
    /* Keep the scroll range the same. */
    margin-top:  800px;
  }
</style>
<body>
  <div id="scroller">
    <div id="target"></div>
  </div>
</body>
<script type="text/javascript">
  document.documentElement.addEventListener('TestRendered', async () => {
    runTest();
  }, { once: true });

  async function runTest() {
    await waitForCompositorReady();

    const anim = target.getAnimations()[0];

    // Scroll to exit 50%.
    scroller.scrollTop = 800;
    await waitForNextFrame();

    // After the update to the animation range, the positioning is exit 0%
    target.classList.add('bounds-update');
    await waitForNextFrame();

    // Make sure change to animation range was properly picked up.
    document.documentElement.classList.remove("reftest-wait");
  }
</script>
</body>
</html>
