/* -*- 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/. */

#ifndef NS_SMILTIMEVALUESPEC_H_

#define NS_SMILTIMEVALUESPEC_H_

#include "mozilla/Attributes.h"

#include "mozilla/dom/IDTracker.h"

#include "nsSMILTimeValueSpecParams.h"

#include "nsStringFwd.h"

#include "nsIDOMEventListener.h"

class nsSMILTimeValue;

class nsSMILTimedElement;

class nsSMILTimeContainer;

class nsSMILInstanceTime;

class nsSMILInterval;

namespace mozilla {

namespace dom {

class Event;

} // namespace dom

class EventListenerManager;

} // namespace mozilla

//----------------------------------------------------------------------

// nsSMILTimeValueSpec class

//

// An individual element of a 'begin' or 'end' attribute, e.g. '5s', 'a.end'.

// This class handles the parsing of such specifications and performs the

// necessary event handling (for event and repeat specifications)

// and synchronisation (for syncbase specifications).

//

// For an overview of how this class is related to other SMIL time classes see

// the documentation in nsSMILTimeValue.h

class nsSMILTimeValueSpec

{

public:

  typedef mozilla::dom::Element Element;

  typedef mozilla::dom::Event Event;

  typedef mozilla::dom::IDTracker IDTracker;

  nsSMILTimeValueSpec(nsSMILTimedElement& aOwner, bool aIsBegin);

  ~nsSMILTimeValueSpec();

  nsresult SetSpec(const nsAString& aStringSpec, Element& aContextElement);

  void ResolveReferences(Element& aContextElement);

  bool IsEventBased() const;

  void     HandleNewInterval(nsSMILInterval& aInterval,

                             const nsSMILTimeContainer* aSrcContainer);

  void     HandleTargetElementChange(Element* aNewTarget);

  // For created nsSMILInstanceTime objects

  bool     DependsOnBegin() const;

  void     HandleChangedInstanceTime(const nsSMILInstanceTime& aBaseTime,

                                     const nsSMILTimeContainer* aSrcContainer,

                                     nsSMILInstanceTime& aInstanceTimeToUpdate,

                                     bool aObjectChanged);

  void     HandleDeletedInstanceTime(nsSMILInstanceTime& aInstanceTime);

  // Cycle-collection support

  void Traverse(nsCycleCollectionTraversalCallback* aCallback);

  void Unlink();

protected:

  void UpdateReferencedElement(Element* aFrom, Element* aTo);

  void UnregisterFromReferencedElement(Element* aElement);

  nsSMILTimedElement* GetTimedElement(Element* aElement);

  bool IsWhitelistedEvent();

  void RegisterEventListener(Element* aElement);

  void UnregisterEventListener(Element* aElement);

  void HandleEvent(Event* aEvent);

  bool CheckRepeatEventDetail(Event* aEvent);

  nsSMILTimeValue ConvertBetweenTimeContainers(const nsSMILTimeValue& aSrcTime,

                                      const nsSMILTimeContainer* aSrcContainer);

  bool ApplyOffset(nsSMILTimeValue& aTime) const;

  nsSMILTimedElement*           mOwner;

  bool                          mIsBegin; // Indicates if *we* are a begin spec,

                                          // not to be confused with

                                          // mParams.mSyncBegin which indicates

                                          // if we're synced with the begin of

                                          // the target.

  nsSMILTimeValueSpecParams     mParams;

  /**

   * If our nsSMILTimeValueSpec exists for a 'begin' or 'end' attribute with a

   * value that specifies a time that is relative to the animation of some

   * other element, it will create an instance of this class to reference and

   * track that other element.  For example, if the nsSMILTimeValueSpec is for

   * end='a.end+2s', an instance of this class will be created to track the

   * element associated with the element ID "a".  This class will notify the

   * nsSMILTimeValueSpec if the element that that ID identifies changes to a

   * different element (or none).

   */

  class TimeReferenceTracker final : public IDTracker

  {

  public:

    explicit TimeReferenceTracker(nsSMILTimeValueSpec* aOwner)

      : mSpec(aOwner)

    {}

    void ResetWithElement(Element* aTo) {

      RefPtr<Element> from = get();

      Unlink();

      ElementChanged(from, aTo);

    }

  protected:

    virtual void ElementChanged(Element* aFrom, Element* aTo) override

    {

      IDTracker::ElementChanged(aFrom, aTo);

      mSpec->UpdateReferencedElement(aFrom, aTo);

    }

    virtual bool IsPersistent() override { return true; }

  private:

    nsSMILTimeValueSpec* mSpec;

  };

  TimeReferenceTracker mReferencedElement;

  class EventListener final : public nsIDOMEventListener

  {

    ~EventListener() {}

  public:

    explicit EventListener(nsSMILTimeValueSpec* aOwner) : mSpec(aOwner) { }

    void Disconnect()

    {

      mSpec = nullptr;

    }

    NS_DECL_ISUPPORTS

    NS_DECL_NSIDOMEVENTLISTENER

  private:

    nsSMILTimeValueSpec* mSpec;

  };

  RefPtr<EventListener> mEventListener;

};

#endif // NS_SMILTIMEVALUESPEC_H_