<!DOCTYPE html>
<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>
<script src="resources/fake-vr-displays.js"></script>
<script src="file:///gen/layout_test_data/mojo/public/js/mojo_bindings.js"></script>
<script src="file:///gen/device/vr/vr_service.mojom.js"></script>
<script src="resources/mock-vr-service.js"></script>
<canvas id="webgl-canvas"></canvas>
<script src="resources/presentation-setup.js"></script>
<script>
let fakeDisplays = fakeVRDisplays();

vr_test( (t) => {
  return navigator.getVRDisplays().then( (displays) => {
    let display = displays[0];

    let prePresentFrameCount = 0;

    function onFrameStartup() {
      // Wait until presentation starts, then proceed
      // with the remaining tests.
      if (display.isPresenting) {
        t.step( () => {
          assert_unreached(err);
        }, "unexpectedly presenting");
      } else {
        // Run a few frames in "magic mirror" mode, then start presentation.
        if (++prePresentFrameCount == 3) {
          runWithUserGesture(startPresentation);
        } else {
          display.requestAnimationFrame(onFrameStartup);
        }
      }
    }

    function onFrame1() {
      // case (b): submit frame first, then rAF
      display.submitFrame();
      display.requestAnimationFrame(onFrame2);
    }

    function onFrame2() {
      // case (c): rAF first, then submit frame
      display.requestAnimationFrame(onFrame3);
      display.submitFrame();
    }

    function onFrame3(time) {
      // case (d): don't submit a frame.
      display.requestAnimationFrame(onFrame4);
    }

    function onFrame4(time) {
      // If we get here, we're done.
      t.done();
    }

    function startPresentation() {
      display.requestPresent([{ source : webglCanvas }]).then( () => {
        t.step( () => {
          // case (a): in requestPresent promise, outside animating context.
          assert_true(display.isPresenting);
          display.requestAnimationFrame(onFrame1);
        }, "Display should be presenting");
      }, (err) => {
        t.step( () => {
          assert_unreached(err);
        }, "requestPresent rejected");
      });
    }

    // Start: case (a) outside animating context.
    display.requestAnimationFrame(onFrameStartup);
  }, (err) => {
    t.step( () => {
      assert_unreached("getVRDisplays rejected");
    });
    t.done();
  });
}, [fakeDisplays["Pixel"]],
"multiple requestAnimationFrame requests call the correct callbacks");

</script>