<!DOCTYPE html>
<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>
<script src="file:///gen/layout_test_data/mojo/public/js/mojo_bindings.js"></script>
<script src="file:///gen/device/vr/public/mojom/vr_service.mojom.js"></script>
<script src="../external/wpt/resources/chromium/webxr-test.js"></script>
<script src="../external/wpt/webxr/resources/webxr_test_constants.js"></script>
<script src="../xr/resources/xr-internal-device-mocking.js"></script>
<script src="../xr/resources/xr-test-utils.js"></script>
<canvas id="webgl-canvas"></canvas>

<script>
let testName = "Transient input sources fire events in the right order";

let watcherDone = new Event("watcherdone");

let fakeDeviceInitParams = { supportsImmersive:true };

let requestSessionModes = ['immersive-vr'];

let testFunction = function(session, t, fakeDeviceController) {
  let eventWatcher = new EventWatcher(
    t, session, ["inputsourceschange", "selectstart", "select", "selectend", "watcherdone"]);
  let eventPromise = eventWatcher.wait_for(
    ["inputsourceschange", "selectstart", "select", "selectend", "inputsourceschange", "watcherdone"]);

  // Need to have a valid pose or input events don't process.
  fakeDeviceController.setXRPresentationFrameData(VALID_POSE_MATRIX, [{
      eye:"left",
      projectionMatrix: VALID_PROJECTION_MATRIX,
      viewMatrix: VALID_VIEW_MATRIX
    }, {
      eye:"right",
      projectionMatrix: VALID_PROJECTION_MATRIX,
      viewMatrix: VALID_VIEW_MATRIX
    }]);

  let inputChangeEvents = 0;
  let cached_input_source = null;
  function onInputSourcesChange(event) {
    t.step(() => {
      inputChangeEvents++;
      assert_equals(event.session, session);

      // The first change event should be adding our controller.
      if (inputChangeEvents === 1) {
        validateAdded(event.added, 1);
        validateRemoved(event.removed, 0);
        cached_input_source = session.inputSources[0];
        assert_not_equals(cached_input_source, null);
      } else if (inputChangeEvents === 2) {
        // The second event should be removing our controller.
        validateAdded(event.added, 0);
        validateRemoved(event.removed, 1);
        assert_true(event.removed.includes(cached_input_source));
        session.dispatchEvent(watcherDone);
      }
    });
  }

  function validateAdded(added, length) {
    t.step(() => {
      assert_not_equals(added, null);
      assert_equals(added.length, length,
          "Added length matches expectations");

      let currentSources = Array.from(session.inputSources.values());
      added.forEach((source) => {
        assert_true(currentSources.includes(source),
          "Every element in added should be in the input source list");
      });
    });
  }

  function validateRemoved(removed, length) {
    t.step(() => {
      assert_not_equals(removed, null);
        assert_equals(removed.length, length,
            "Removed length matches expectations");

      let currentSources = Array.from(session.inputSources.values());
      removed.forEach((source) => {
        assert_false(currentSources.includes(source),
          "No element in removed should be in the input source list");
      });
    });
  }

  session.addEventListener('inputsourceschange', onInputSourcesChange, false);

  // Session must have a baseLayer or frame requests will be ignored.
  session.updateRenderState({ baseLayer: new XRWebGLLayer(session, gl) });

  // Create our input source and immediately toggle the primary input so that
  // it appears as already needing to send a click event when it appears.
  let input_source = new MockXRInputSource();
  input_source.primaryInputPressed = true;
  input_source.primaryInputPressed = false;
  fakeDeviceController.addInputSource(input_source);

  // Make our input source disappear after one frame, and wait an additional
  // frame for that disappearance to propogate.
  session.requestAnimationFrame((time, xrFrame) => {
    fakeDeviceController.removeInputSource(input_source);
    session.requestAnimationFrame((time, xrFrame) => {

    });
  });

  return eventPromise;
};

xr_session_promise_test(
  testFunction, fakeDeviceInitParams, requestSessionModes, testName);
</script>