1 files changed, 291 insertions, 0 deletions
diff --git a/dom/animation/TimingParams.cpp b/dom/animation/TimingParams.cpp
new file mode 100644
index 0000000000..80a05a95c4
--- /dev/null
+++ b/dom/animation/TimingParams.cpp
@@ -0,0 +1,291 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/TimingParams.h"
+
+#include "mozilla/AnimationUtils.h"
+#include "mozilla/dom/AnimatableBinding.h"
+#include "mozilla/dom/Document.h"
+#include "mozilla/dom/KeyframeAnimationOptionsBinding.h"
+#include "mozilla/dom/KeyframeEffectBinding.h"
+#include "mozilla/ServoCSSParser.h"
+
+namespace mozilla {
+
+template <class OptionsType>
+static const dom::EffectTiming& GetTimingProperties(
+    const OptionsType& aOptions);
+
+template <>
+/* static */
+const dom::EffectTiming& GetTimingProperties(
+    const dom::UnrestrictedDoubleOrKeyframeEffectOptions& aOptions) {
+  MOZ_ASSERT(aOptions.IsKeyframeEffectOptions());
+  return aOptions.GetAsKeyframeEffectOptions();
+}
+
+template <>
+/* static */
+const dom::EffectTiming& GetTimingProperties(
+    const dom::UnrestrictedDoubleOrKeyframeAnimationOptions& aOptions) {
+  MOZ_ASSERT(aOptions.IsKeyframeAnimationOptions());
+  return aOptions.GetAsKeyframeAnimationOptions();
+}
+
+template <class OptionsType>
+/* static */
+TimingParams TimingParams::FromOptionsType(const OptionsType& aOptions,
+                                           ErrorResult& aRv) {
+  TimingParams result;
+
+  if (aOptions.IsUnrestrictedDouble()) {
+    double durationInMs = aOptions.GetAsUnrestrictedDouble();
+    if (durationInMs >= 0) {
+      result.mDuration.emplace(
+          StickyTimeDuration::FromMilliseconds(durationInMs));
+    } else {
+      nsPrintfCString error("Duration value %g is less than 0", durationInMs);
+      aRv.ThrowTypeError(error);
+      return result;
+    }
+    result.Update();
+  } else {
+    const dom::EffectTiming& timing = GetTimingProperties(aOptions);
+    result = FromEffectTiming(timing, aRv);
+  }
+
+  return result;
+}
+
+/* static */
+TimingParams TimingParams::FromOptionsUnion(
+    const dom::UnrestrictedDoubleOrKeyframeEffectOptions& aOptions,
+    ErrorResult& aRv) {
+  return FromOptionsType(aOptions, aRv);
+}
+
+/* static */
+TimingParams TimingParams::FromOptionsUnion(
+    const dom::UnrestrictedDoubleOrKeyframeAnimationOptions& aOptions,
+    ErrorResult& aRv) {
+  return FromOptionsType(aOptions, aRv);
+}
+
+/* static */
+TimingParams TimingParams::FromEffectTiming(
+    const dom::EffectTiming& aEffectTiming, ErrorResult& aRv) {
+  TimingParams result;
+
+  Maybe<StickyTimeDuration> duration =
+      TimingParams::ParseDuration(aEffectTiming.mDuration, aRv);
+  if (aRv.Failed()) {
+    return result;
+  }
+  TimingParams::ValidateIterationStart(aEffectTiming.mIterationStart, aRv);
+  if (aRv.Failed()) {
+    return result;
+  }
+  TimingParams::ValidateIterations(aEffectTiming.mIterations, aRv);
+  if (aRv.Failed()) {
+    return result;
+  }
+  Maybe<StyleComputedTimingFunction> easing =
+      ParseEasing(aEffectTiming.mEasing, aRv);
+  if (aRv.Failed()) {
+    return result;
+  }
+
+  result.mDuration = duration;
+  result.mDelay = TimeDuration::FromMilliseconds(aEffectTiming.mDelay);
+  result.mEndDelay = TimeDuration::FromMilliseconds(aEffectTiming.mEndDelay);
+  result.mIterations = aEffectTiming.mIterations;
+  result.mIterationStart = aEffectTiming.mIterationStart;
+  result.mDirection = aEffectTiming.mDirection;
+  result.mFill = aEffectTiming.mFill;
+  result.mFunction = std::move(easing);
+
+  result.Update();
+
+  return result;
+}
+
+/* static */
+TimingParams TimingParams::MergeOptionalEffectTiming(
+    const TimingParams& aSource, const dom::OptionalEffectTiming& aEffectTiming,
+    ErrorResult& aRv) {
+  MOZ_ASSERT(!aRv.Failed(), "Initially return value should be ok");
+
+  TimingParams result = aSource;
+
+  // Check for errors first
+
+  Maybe<StickyTimeDuration> duration;
+  if (aEffectTiming.mDuration.WasPassed()) {
+    duration =
+        TimingParams::ParseDuration(aEffectTiming.mDuration.Value(), aRv);
+    if (aRv.Failed()) {
+      return result;
+    }
+  }
+
+  if (aEffectTiming.mIterationStart.WasPassed()) {
+    TimingParams::ValidateIterationStart(aEffectTiming.mIterationStart.Value(),
+                                         aRv);
+    if (aRv.Failed()) {
+      return result;
+    }
+  }
+
+  if (aEffectTiming.mIterations.WasPassed()) {
+    TimingParams::ValidateIterations(aEffectTiming.mIterations.Value(), aRv);
+    if (aRv.Failed()) {
+      return result;
+    }
+  }
+
+  Maybe<StyleComputedTimingFunction> easing;
+  if (aEffectTiming.mEasing.WasPassed()) {
+    easing = ParseEasing(aEffectTiming.mEasing.Value(), aRv);
+    if (aRv.Failed()) {
+      return result;
+    }
+  }
+
+  // Assign values
+
+  if (aEffectTiming.mDuration.WasPassed()) {
+    result.mDuration = duration;
+  }
+  if (aEffectTiming.mDelay.WasPassed()) {
+    result.mDelay =
+        TimeDuration::FromMilliseconds(aEffectTiming.mDelay.Value());
+  }
+  if (aEffectTiming.mEndDelay.WasPassed()) {
+    result.mEndDelay =
+        TimeDuration::FromMilliseconds(aEffectTiming.mEndDelay.Value());
+  }
+  if (aEffectTiming.mIterations.WasPassed()) {
+    result.mIterations = aEffectTiming.mIterations.Value();
+  }
+  if (aEffectTiming.mIterationStart.WasPassed()) {
+    result.mIterationStart = aEffectTiming.mIterationStart.Value();
+  }
+  if (aEffectTiming.mDirection.WasPassed()) {
+    result.mDirection = aEffectTiming.mDirection.Value();
+  }
+  if (aEffectTiming.mFill.WasPassed()) {
+    result.mFill = aEffectTiming.mFill.Value();
+  }
+  if (aEffectTiming.mEasing.WasPassed()) {
+    result.mFunction = easing;
+  }
+
+  result.Update();
+
+  return result;
+}
+
+/* static */
+Maybe<StyleComputedTimingFunction> TimingParams::ParseEasing(
+    const nsACString& aEasing, ErrorResult& aRv) {
+  StyleComputedTimingFunction timingFunction;
+  if (!ServoCSSParser::ParseEasing(aEasing, timingFunction)) {
+    aRv.ThrowTypeError<dom::MSG_INVALID_EASING_ERROR>(aEasing);
+    return Nothing();
+  }
+
+  if (timingFunction.IsLinearKeyword()) {
+    return Nothing();
+  }
+
+  return Some(std::move(timingFunction));
+}
+
+bool TimingParams::operator==(const TimingParams& aOther) const {
+  // We don't compare mActiveDuration and mEndTime because they are calculated
+  // from other timing parameters.
+  return mDuration == aOther.mDuration && mDelay == aOther.mDelay &&
+         mEndDelay == aOther.mEndDelay && mIterations == aOther.mIterations &&
+         mIterationStart == aOther.mIterationStart &&
+         mDirection == aOther.mDirection && mFill == aOther.mFill &&
+         mFunction == aOther.mFunction;
+}
+
+// FIXME: This is a tentative way to normalize the timing which is defined in
+// [web-animations-2] [1]. I borrow this implementation and some concepts for
+// the edge cases from Chromium [2] so we can match the behavior with them. The
+// implementation here ignores the case of percentage of start delay, end delay,
+// and duration because Gecko doesn't support them. We may have to update the
+// calculation if the spec issue [3] gets any update.
+//
+// [1]
+// https://drafts.csswg.org/web-animations-2/#time-based-animation-to-a-proportional-animation
+// [2] https://chromium-review.googlesource.com/c/chromium/src/+/2992387
+// [3] https://github.com/w3c/csswg-drafts/issues/4862
+TimingParams TimingParams::Normalize(
+    const TimeDuration& aTimelineDuration) const {
+  MOZ_ASSERT(aTimelineDuration,
+             "the timeline duration of scroll-timeline is always non-zero now");
+
+  TimingParams normalizedTiming(*this);
+
+  // Handle iteration duration value of "auto" first.
+  // FIXME: Bug 1676794: Gecko doesn't support `animation-duration:auto` and we
+  // don't support JS-generated scroll animations, so we don't fall into this
+  // case for now. Need to check this again after we support ScrollTimeline
+  // interface.
+  if (!mDuration) {
+    // If the iteration duration is auto, then:
+    //   Set start delay and end delay to 0, as it is not possible to mix time
+    //   and proportions.
+    normalizedTiming.mDelay = TimeDuration();
+    normalizedTiming.mEndDelay = TimeDuration();
+    normalizedTiming.Update();
+    return normalizedTiming;
+  }
+
+  if (mEndTime.IsZero()) {
+    // mEndTime of zero causes division by zero so we handle it here.
+    //
+    // FIXME: The spec doesn't mention this case, so we might have to update
+    // this based on the spec issue,
+    // https://github.com/w3c/csswg-drafts/issues/7459.
+    normalizedTiming.mDelay = TimeDuration();
+    normalizedTiming.mEndDelay = TimeDuration();
+    normalizedTiming.mDuration = Some(TimeDuration());
+  } else if (mEndTime == TimeDuration::Forever()) {
+    // The iteration count or duration may be infinite; however, start and
+    // end delays are strictly finite. Thus, in the limit when end time
+    // approaches infinity:
+    //    start delay / end time = finite / infinite = 0
+    //    end delay / end time = finite / infinite = 0
+    //    iteration duration / end time = 1 / iteration count
+    // This condition can be reached by switching to a scroll timeline on
+    // an existing infinite duration animation.
+    //
+    // FIXME: The spec doesn't mention this case, so we might have to update
+    // this based on the spec issue,
+    // https://github.com/w3c/csswg-drafts/issues/7459.
+    normalizedTiming.mDelay = TimeDuration();
+    normalizedTiming.mEndDelay = TimeDuration();
+    normalizedTiming.mDuration =
+        Some(aTimelineDuration.MultDouble(1.0 / mIterations));
+  } else {
+    // Convert to percentages then multiply by the timeline duration.
+    const double endTimeInSec = mEndTime.ToSeconds();
+    normalizedTiming.mDelay =
+        aTimelineDuration.MultDouble(mDelay.ToSeconds() / endTimeInSec);
+    normalizedTiming.mEndDelay =
+        aTimelineDuration.MultDouble(mEndDelay.ToSeconds() / endTimeInSec);
+    normalizedTiming.mDuration = Some(StickyTimeDuration(
+        aTimelineDuration.MultDouble(mDuration->ToSeconds() / endTimeInSec)));
+  }
+
+  normalizedTiming.Update();
+  return normalizedTiming;
+}
+
+}  // namespace mozilla