<!doctype html>
<meta charset="utf-8">
<title>
  Async Clipboard write [image/png ClipboardItem] ->
        read [image/png ClipboardItem] tests
</title>
<link rel="help" href="https://w3c.github.io/clipboard-apis/#async-clipboard-api">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script src="resources/user-activation.js"></script>
<body>Body needed for test_driver.click()
<p>
  <p>The bottom image should display the same image as the top image.</p>
  <p>Original Image:</p>
  <image id="image-to-copy" width="20" height="20"
        src="resources/greenbox.png"></image>
  <p>Image after copy/paste:</p>
  <image id="image-on-clipboard"></image>
  <canvas id="canvas" width="20" height="20"></canvas>
</p>

<script>
// Must compare a bitmap as opposed to simply blob data, because an encoded
// image may have different contents depending on encoder.
async function getBitmapString(blob) {
  const imageBitmap = await createImageBitmap(blob);
  const canvas = document.getElementById('canvas');
  const ctx = canvas.getContext('2d');

  ctx.drawImage(imageBitmap, 0,0);

  let imageData = ctx.getImageData(0, 0, canvas.width, canvas.height);
  ctx.clearRect(0, 0, canvas.width, canvas.height);
  return imageData.data.toString();
};

async function loadBlob(fileName) {
  const fetched = await fetch(fileName);
  return await fetched.blob();
}

promise_test(async t => {
  await tryGrantReadPermission();
  await tryGrantWritePermission();

  const blobInput = await loadBlob('resources/greenbox.png');

  assert_equals(blobInput.type, 'image/png');
  const clipboardItemInput = new ClipboardItem({'image/png' : blobInput});
  await waitForUserActivation();
  await navigator.clipboard.write([clipboardItemInput]);
  await waitForUserActivation();
  const clipboardItems = await navigator.clipboard.read();

  assert_equals(clipboardItems.length, 1);
  const clipboardItem = clipboardItems[0];
  assert_true(clipboardItem instanceof ClipboardItem);
  assert_equals(clipboardItem.types.length, 1);
  const blobOutput = await clipboardItem.getType('image/png');
  assert_equals(blobOutput.type, 'image/png');

  document.getElementById('image-on-clipboard').src =
      window.URL.createObjectURL(blobOutput);

  const comparableInput = await getBitmapString(blobInput);
  const comparableOutput = await getBitmapString(blobOutput);

  assert_equals(comparableOutput, comparableInput);
}, 'Verify write and read clipboard [image/png Blob]');

promise_test(async t => {
  await tryGrantReadPermission();
  await tryGrantWritePermission();

  const invalidPngBlob = new Blob(['this text is not a valid png image'],
      {type: 'image/png'});
  const clipboardItemInput = new ClipboardItem({'image/png' : invalidPngBlob});
  await waitForUserActivation();
  await promise_rejects_dom(t, 'DataError',
      navigator.clipboard.write([clipboardItemInput]));
}, 'Verify write error on malformed data [image/png ClipboardItem]');
</script>
</body>