<!DOCTYPE html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<body>
<canvas id='canvas' width=10 height=10></canvas>
</body>
<script>

// This test verifies that MediaStreamTrack.applyConstraints() exists and that,
// when called with no parameters, returns a Promise that is resolved. This
// might not make sense: https://github.com/w3c/mediacapture-main/issues/438 .
// Other tests go deeper.
promise_test(function(t) {
  var canvas = document.getElementById('canvas');
  var context = canvas.getContext("2d");
  context.fillStyle = "red";
  context.fillRect(0, 0, 10, 10);

  var stream = canvas.captureStream();
  assert_equals(stream.getAudioTracks().length, 0);
  assert_equals(stream.getVideoTracks().length, 1);

  var videoTrack = stream.getVideoTracks()[0];
  return videoTrack.applyConstraints();
}, 'MediaStreamTrack.applyConstraints()');

// This test verifies that MediaStreamTrack.applyConstraints() exists and that,
// when called with an empty advanced constraint set, returns a Promise that is
// resolved.
promise_test(function(t) {
  var canvas = document.getElementById('canvas');
  var context = canvas.getContext("2d");
  context.fillStyle = "red";
  context.fillRect(0, 0, 10, 10);

  var stream = canvas.captureStream();
  assert_equals(stream.getAudioTracks().length, 0);
  assert_equals(stream.getVideoTracks().length, 1);

  var videoTrack = stream.getVideoTracks()[0];
  return videoTrack.applyConstraints({advanced: []});
}, 'MediaStreamTrack.applyConstraints({advanced: []})');

// This test verifies that applyConstraints() rejects the returned Promise if
// passed a non-supported image-capture constraint (https://crbug.com/711694).
promise_test(async function(t) {
  var canvas = document.getElementById('canvas');
  var context = canvas.getContext("2d");
  context.fillStyle = "red";
  context.fillRect(0, 0, 10, 10);

  var stream = canvas.captureStream();
  var videoTrack = stream.getVideoTracks()[0];

  // Use e.g. |torch| as an example of unsupported constraint.
  assert_false("torch" in videoTrack.getCapabilities());
  try {
    await videoTrack.applyConstraints({torch: {exact: true}});
  } catch (error) {
    assert_equals(error.name, 'OverconstrainedError');
    assert_equals(error.constraint, 'torch');
    return;
  }
  assert_unreached('expected applyConstraints to reject');
}, 'MediaStreamTrack.applyConstraints() with unsupported constraint');

</script>
