text: /*
   * Copyright (C) 2013 Google Inc. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are
   * met:
   *
   *     * Redistributions of source code must retain the above copyright
   * notice, this list of conditions and the following disclaimer.
   *     * Redistributions in binary form must reproduce the above
   * copyright notice, this list of conditions and the following disclaimer
   * in the documentation and/or other materials provided with the
   * distribution.
   *     * Neither the name of Google Inc. nor the names of its
   * contributors may be used to endorse or promote products derived from
   * this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #ifndef AnimationPlayer_h
  #define AnimationPlayer_h
  
  #include "core/animation/AnimationNode.h"
  #include "core/dom/ActiveDOMObject.h"
  #include "core/events/EventTarget.h"
  #include "platform/heap/Handle.h"
  #include "wtf/RefPtr.h"
  
  namespace blink {
  
  class AnimationTimeline;
  class ExceptionState;
  
  class AnimationPlayer final
      : public EventTargetWithInlineData
      , public RefCountedWillBeNoBase<AnimationPlayer>
      , public ActiveDOMObject {
      DEFINE_WRAPPERTYPEINFO();
      REFCOUNTED_EVENT_TARGET(AnimationPlayer);
  public:
      enum AnimationPlayState {
          Idle,
          Pending,
          Running,
          Paused,
          Finished
      };
  
      ~AnimationPlayer();
      static PassRefPtrWillBeRawPtr<AnimationPlayer> create(ExecutionContext*, AnimationTimeline&, AnimationNode*);
  
      // Returns whether the player is finished.
      bool update(TimingUpdateReason);
  
      // timeToEffectChange returns:
      //  infinity  - if this player is no longer in effect
      //  0         - if this player requires an update on the next frame
      //  n         - if this player requires an update after 'n' units of time
      double timeToEffectChange();
  
      void cancel();
  
      double currentTime(bool& isNull);
      double currentTime();
      void setCurrentTime(double newCurrentTime);
  
      double currentTimeInternal() const;
  
      void setCurrentTimeInternal(double newCurrentTime, TimingUpdateReason = TimingUpdateOnDemand);
      bool paused() const { return m_paused && !m_isPausedForTesting; }
      static const char* playStateString(AnimationPlayState);
      String playState() { return playStateString(playStateInternal()); }
      AnimationPlayState playStateInternal() const;
  
      void pause();
      void play();
      void reverse();
      void finish(ExceptionState&);
      bool finished() const { return m_playState != Idle && limited(currentTimeInternal()); }
      bool playing() const { return !(playStateInternal() == Idle || finished() || m_paused || m_isPausedForTesting); }
      // FIXME: Resolve whether finished() should just return the flag, and
      // remove this method.
      bool finishedInternal() const { return m_finished; }
  
      DEFINE_ATTRIBUTE_EVENT_LISTENER(finish);
  
      virtual const AtomicString& interfaceName() const override;
      virtual ExecutionContext* executionContext() const override;
      virtual bool hasPendingActivity() const override;
      virtual void stop() override;
      virtual bool dispatchEvent(PassRefPtrWillBeRawPtr<Event>) override;
  
      double playbackRate() const;
      void setPlaybackRate(double);
      const AnimationTimeline* timeline() const { return m_timeline; }
      AnimationTimeline* timeline() { return m_timeline; }
  
  #if !ENABLE(OILPAN)
      void timelineDestroyed() { m_timeline = nullptr; }
  #endif
  
      double calculateStartTime(double currentTime) const;
      bool hasStartTime() const { return !isNull(m_startTime); }
      double startTime(bool& isNull) const;
      double startTime() const;
      double startTimeInternal() const { return m_startTime; }
      void setStartTime(double);
      void setStartTimeInternal(double);
  
      const AnimationNode* source() const { return m_content.get(); }
      AnimationNode* source() { return m_content.get(); }
      void setSource(AnimationNode*);
  
      // Pausing via this method is not reflected in the value returned by
      // paused() and must never overlap with pausing via pause().
      void pauseForTesting(double pauseTime);
      // This should only be used for CSS
      void unpause();
  
      void setOutdated();
      bool outdated() { return m_outdated; }
  
      bool canStartAnimationOnCompositor();
      bool maybeStartAnimationOnCompositor();
      void cancelAnimationOnCompositor();
      bool hasActiveAnimationsOnCompositor();
      void setCompositorPending(bool sourceChanged = false);
      void notifyCompositorStartTime(double timelineTime);
      void notifyStartTime(double timelineTime);
  
  
      void preCommit(int compositorGroup, bool startOnCompositor);
      void postCommit(double timelineTime);
  
      unsigned sequenceNumber() const { return m_sequenceNumber; }
      int compositorGroup() const { return m_compositorGroup; }
  
      static bool hasLowerPriority(AnimationPlayer* player1, AnimationPlayer* player2)
      {
          return player1->sequenceNumber() < player2->sequenceNumber();
      }
  
  #if !ENABLE(OILPAN)
      // Checks if the AnimationStack is the last reference holder to the Player.
      // This won't be needed when AnimationPlayer is moved to Oilpan.
      bool canFree() const;
  #endif
  
      virtual bool addEventListener(const AtomicString& eventType, PassRefPtr<EventListener>, bool useCapture = false) override;
  
      virtual void trace(Visitor*) override;
  
  private:
      AnimationPlayer(ExecutionContext*, AnimationTimeline&, AnimationNode*);
  
      double sourceEnd() const;
      bool limited(double currentTime) const;
  
      AnimationPlayState calculatePlayState();
      double calculateCurrentTime() const;
  
      void unpauseInternal();
      void setPlaybackRateInternal(double);
      void updateCurrentTimingState(TimingUpdateReason);
  
      void beginUpdatingState();
      void endUpdatingState();
  
      AnimationPlayState m_playState;
      double m_playbackRate;
      double m_startTime;
      double m_holdTime;
  
      unsigned m_sequenceNumber;
  
      RefPtrWillBeMember<AnimationNode> m_content;
      RawPtrWillBeMember<AnimationTimeline> m_timeline;
      // Reflects all pausing, including via pauseForTesting().
      bool m_paused;
      bool m_held;
      bool m_isPausedForTesting;
  
      // This indicates timing information relevant to the player's effect
      // has changed by means other than the ordinary progression of time
      bool m_outdated;
  
      bool m_finished;
      // Holds a 'finished' event queued for asynchronous dispatch via the
      // ScriptedAnimationController. This object remains active until the
      // event is actually dispatched.
      RefPtrWillBeMember<Event> m_pendingFinishedEvent;
  
      enum CompositorAction {
          None,
          Pause,
          Start,
          PauseThenStart
      };
  
      class CompositorState {
      public:
          CompositorState(AnimationPlayer& player)
              : startTime(player.m_startTime)
              , holdTime(player.m_holdTime)
              , playbackRate(player.m_playbackRate)
              , sourceChanged(false)
              , pendingAction(Start)
          { }
          double startTime;
          double holdTime;
          double playbackRate;
          bool sourceChanged;
          CompositorAction pendingAction;
      };
  
      enum CompositorPendingChange {
          SetCompositorPending,
          SetCompositorPendingWithSourceChanged,
          DoNotSetCompositorPending,
      };
  
      class PlayStateUpdateScope {
          STACK_ALLOCATED();
      public:
          PlayStateUpdateScope(AnimationPlayer&, TimingUpdateReason, CompositorPendingChange = SetCompositorPending);
          ~PlayStateUpdateScope();
      private:
          RawPtrWillBeMember<AnimationPlayer> m_player;
          AnimationPlayState m_initial;
          CompositorPendingChange m_compositorPendingChange;
      };
  
      // This mirrors the known compositor state. It is created when a compositor
      // animation is started. Updated once the start time is known and each time
      // modifications are pushed to the compositor.
      OwnPtr<CompositorState> m_compositorState;
      bool m_compositorPending;
      int m_compositorGroup;
  
      bool m_currentTimePending;
      bool m_stateIsBeingUpdated;
  };
  
  } // namespace blink
  
  #endif // AnimationPlayer_h
  