/* -*- 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 "PendingAnimationTracker.h"

#include "mozilla/dom/AnimationTimeline.h"

#include "mozilla/dom/Nullable.h"

#include "nsIFrame.h"

#include "nsIPresShell.h"

using mozilla::dom::Nullable;

namespace mozilla {

NS_IMPL_CYCLE_COLLECTION(PendingAnimationTracker,

                         mPlayPendingSet,

                         mPausePendingSet,

                         mDocument)

NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(PendingAnimationTracker, AddRef)

NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(PendingAnimationTracker, Release)

void

PendingAnimationTracker::AddPending(dom::Animation& aAnimation,

                                    AnimationSet& aSet)

{

  aSet.PutEntry(&aAnimation);

  // Schedule a paint. Otherwise animations that don't trigger a paint by

  // themselves (e.g. CSS animations with an empty keyframes rule) won't

  // start until something else paints.

  EnsurePaintIsScheduled();

}

void

PendingAnimationTracker::RemovePending(dom::Animation& aAnimation,

                                       AnimationSet& aSet)

{

  aSet.RemoveEntry(&aAnimation);

}

bool

PendingAnimationTracker::IsWaiting(const dom::Animation& aAnimation,

                                   const AnimationSet& aSet) const

{

  return aSet.Contains(const_cast<dom::Animation*>(&aAnimation));

}

void

PendingAnimationTracker::TriggerPendingAnimationsOnNextTick(const TimeStamp&

                                                        aReadyTime)

{

  auto triggerAnimationsAtReadyTime = [aReadyTime](AnimationSet& aAnimationSet)

  {

    for (auto iter = aAnimationSet.Iter(); !iter.Done(); iter.Next()) {

      dom::Animation* animation = iter.Get()->GetKey();

      dom::AnimationTimeline* timeline = animation->GetTimeline();

      // If the animation does not have a timeline, just drop it from the map.

      // The animation will detect that it is not being tracked and will trigger

      // itself on the next tick where it has a timeline.

      if (!timeline) {

        iter.Remove();

        continue;

      }

      // When the timeline's refresh driver is under test control, its values

      // have no correspondance to wallclock times so we shouldn't try to

      // convert aReadyTime (which is a wallclock time) to a timeline value.

      // Instead, the animation will be started/paused when the refresh driver

      // is next advanced since this will trigger a call to

      // TriggerPendingAnimationsNow.

      if (!timeline->TracksWallclockTime()) {

        continue;

      }

      Nullable<TimeDuration> readyTime = timeline->ToTimelineTime(aReadyTime);

      animation->TriggerOnNextTick(readyTime);

      iter.Remove();

    }

  };

  triggerAnimationsAtReadyTime(mPlayPendingSet);

  triggerAnimationsAtReadyTime(mPausePendingSet);

  mHasPlayPendingGeometricAnimations = mPlayPendingSet.Count()

                                       ? CheckState::Indeterminate

                                       : CheckState::Absent;

}

void

PendingAnimationTracker::TriggerPendingAnimationsNow()

{

  auto triggerAndClearAnimations = [](AnimationSet& aAnimationSet) {

    for (auto iter = aAnimationSet.Iter(); !iter.Done(); iter.Next()) {

      iter.Get()->GetKey()->TriggerNow();

    }

    aAnimationSet.Clear();

  };

  triggerAndClearAnimations(mPlayPendingSet);

  triggerAndClearAnimations(mPausePendingSet);

  mHasPlayPendingGeometricAnimations = CheckState::Absent;

}

void

PendingAnimationTracker::MarkAnimationsThatMightNeedSynchronization()

{

  // We only ever set mHasPlayPendingGeometricAnimations to 'present' in

  // HasPlayPendingGeometricAnimations(). So, if it is 'present' already,

  // (i.e. before calling HasPlayPendingGeometricAnimations()) we can assume

  // that this method has already been called for the current set of

  // play-pending animations and it is not necessary to run again.

  //

  // We can't make the same assumption about 'absent', but if this method

  // was already called and the result was 'absent', then this method is

  // a no-op anyway so it's ok to run again.

  //

  // Note that *without* this optimization, starting animations would become

  // O(n^2) in that case where each animation is on a different element and

  // contains a compositor-animatable property since we would end up iterating

  // over all animations in the play-pending set for each target element.

  if (mHasPlayPendingGeometricAnimations == CheckState::Present) {

    return;

  }

  if (!HasPlayPendingGeometricAnimations()) {

    return;

  }

  for (auto iter = mPlayPendingSet.Iter(); !iter.Done(); iter.Next()) {

    iter.Get()->GetKey()->NotifyGeometricAnimationsStartingThisFrame();

  }

}

bool

PendingAnimationTracker::HasPlayPendingGeometricAnimations()

{

  if (mHasPlayPendingGeometricAnimations != CheckState::Indeterminate) {

    return mHasPlayPendingGeometricAnimations == CheckState::Present;

  }

  mHasPlayPendingGeometricAnimations = CheckState::Absent;

  for (auto iter = mPlayPendingSet.ConstIter(); !iter.Done(); iter.Next()) {

    auto animation = iter.Get()->GetKey();

    if (animation->GetEffect() && animation->GetEffect()->AffectsGeometry()) {

      mHasPlayPendingGeometricAnimations = CheckState::Present;

      break;

    }

  }

  return mHasPlayPendingGeometricAnimations == CheckState::Present;

}

void

PendingAnimationTracker::EnsurePaintIsScheduled()

{

  if (!mDocument) {

    return;

  }

  nsIPresShell* presShell = mDocument->GetShell();

  if (!presShell) {

    return;

  }

  nsIFrame* rootFrame = presShell->GetRootFrame();

  if (!rootFrame) {

    return;

  }

  rootFrame->SchedulePaintWithoutInvalidatingObservers();

}

} // namespace mozilla