dom/smil/SMILTimeValueSpec.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef DOM_SMIL_SMILTIMEVALUESPEC_H_
   8 #define DOM_SMIL_SMILTIMEVALUESPEC_H_
   9
  10 #include "mozilla/Attributes.h"
  11 #include "mozilla/SMILTimeValueSpecParams.h"
  12 #include "mozilla/dom/IDTracker.h"
  13 #include "nsStringFwd.h"
  14 #include "nsIDOMEventListener.h"
  15
  16 // XXX Avoid including this here by moving function bodies to the cpp file
  17 #include "mozilla/dom/Element.h"
  18
  19 namespace mozilla {
  20
  21 class EventListenerManager;
  22 class SMILInstanceTime;
  23 class SMILInterval;
  24 class SMILTimeContainer;
  25 class SMILTimedElement;
  26 class SMILTimeValue;
  27
  28 namespace dom {
  29 class Event;
  30 }  // namespace dom
  31
  32 //----------------------------------------------------------------------
  33 // SMILTimeValueSpec class
  34 //
  35 // An individual element of a 'begin' or 'end' attribute, e.g. '5s', 'a.end'.
  36 // This class handles the parsing of such specifications and performs the
  37 // necessary event handling (for event and repeat specifications)
  38 // and synchronisation (for syncbase specifications).
  39 //
  40 // For an overview of how this class is related to other SMIL time classes see
  41 // the documentation in SMILTimeValue.h
  42
  43 class SMILTimeValueSpec {
  44  public:
  45   using Element = dom::Element;
  46   using Event = dom::Event;
  47   using IDTracker = dom::IDTracker;
  48
  49   SMILTimeValueSpec(SMILTimedElement& aOwner, bool aIsBegin);
  50   ~SMILTimeValueSpec();
  51
  52   nsresult SetSpec(const nsAString& aStringSpec, Element& aContextElement);
  53   void ResolveReferences(Element& aContextElement);
  54   bool IsEventBased() const;
  55
  56   void HandleNewInterval(SMILInterval& aInterval,
  57                          const SMILTimeContainer* aSrcContainer);
  58   void HandleTargetElementChange(Element* aNewTarget);
  59
  60   // For created SMILInstanceTime objects
  61   bool DependsOnBegin() const;
  62   void HandleChangedInstanceTime(const SMILInstanceTime& aBaseTime,
  63                                  const SMILTimeContainer* aSrcContainer,
  64                                  SMILInstanceTime& aInstanceTimeToUpdate,
  65                                  bool aObjectChanged);
  66   void HandleDeletedInstanceTime(SMILInstanceTime& aInstanceTime);
  67
  68   // Cycle-collection support
  69   void Traverse(nsCycleCollectionTraversalCallback* aCallback);
  70   void Unlink();
  71
  72  protected:
  73   void UpdateReferencedElement(Element* aFrom, Element* aTo);
  74   void UnregisterFromReferencedElement(Element* aElement);
  75   SMILTimedElement* GetTimedElement(Element* aElement);
  76   bool IsEventAllowedWhenScriptingIsDisabled();
  77   void RegisterEventListener(Element* aTarget);
  78   void UnregisterEventListener(Element* aTarget);
  79   void HandleEvent(Event* aEvent);
  80   bool CheckRepeatEventDetail(Event* aEvent);
  81   SMILTimeValue ConvertBetweenTimeContainers(
  82       const SMILTimeValue& aSrcTime, const SMILTimeContainer* aSrcContainer);
  83   bool ApplyOffset(SMILTimeValue& aTime) const;
  84
  85   SMILTimedElement* mOwner;
  86   bool mIsBegin;  // Indicates if *we* are a begin spec,
  87                   // not to be confused with
  88                   // mParams.mSyncBegin which indicates
  89                   // if we're synced with the begin of
  90                   // the target.
  91   SMILTimeValueSpecParams mParams;
  92
  93   /**
  94    * If our SMILTimeValueSpec exists for a 'begin' or 'end' attribute with a
  95    * value that specifies a time that is relative to the animation of some
  96    * other element, it will create an instance of this class to reference and
  97    * track that other element.  For example, if the SMILTimeValueSpec is for
  98    * end='a.end+2s', an instance of this class will be created to track the
  99    * element associated with the element ID "a".  This class will notify the
 100    * SMILTimeValueSpec if the element that that ID identifies changes to a
 101    * different element (or none).
 102    */
 103   class TimeReferenceTracker final : public IDTracker {
 104    public:
 105     explicit TimeReferenceTracker(SMILTimeValueSpec* aOwner) : mSpec(aOwner) {}
 106     void ResetWithElement(Element* aTo) {
 107       RefPtr<Element> from = get();
 108       Unlink();
 109       ElementChanged(from, aTo);
 110     }
 111
 112    protected:
 113     void ElementChanged(Element* aFrom, Element* aTo) override {
 114       IDTracker::ElementChanged(aFrom, aTo);
 115       mSpec->UpdateReferencedElement(aFrom, aTo);
 116     }
 117     bool IsPersistent() override { return true; }
 118
 119    private:
 120     SMILTimeValueSpec* mSpec;
 121   };
 122
 123   TimeReferenceTracker mReferencedElement;
 124
 125   class EventListener final : public nsIDOMEventListener {
 126     ~EventListener() {}
 127
 128    public:
 129     explicit EventListener(SMILTimeValueSpec* aOwner) : mSpec(aOwner) {}
 130     void Disconnect() { mSpec = nullptr; }
 131
 132     NS_DECL_ISUPPORTS
 133     NS_DECL_NSIDOMEVENTLISTENER
 134
 135    private:
 136     SMILTimeValueSpec* mSpec;
 137   };
 138   RefPtr<EventListener> mEventListener;
 139 };
 140
 141 }  // namespace mozilla
 142
 143 #endif  // DOM_SMIL_SMILTIMEVALUESPEC_H_