/* -*- 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_SMILINTERVAL_H_

#define NS_SMILINTERVAL_H_

#include "nsSMILInstanceTime.h"

#include "nsTArray.h"

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

// nsSMILInterval class

//

// A structure consisting of a begin and end time. The begin time must be

// resolved (i.e. not indefinite or unresolved).

//

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

// the documentation in nsSMILTimeValue.h

class nsSMILInterval

{

public:

  nsSMILInterval();

  nsSMILInterval(const nsSMILInterval& aOther);

  ~nsSMILInterval();

  void Unlink(bool aFiltered = false);

  const nsSMILInstanceTime* Begin() const

  {

    MOZ_ASSERT(mBegin && mEnd,

               "Requesting Begin() on un-initialized instance time");

    return mBegin;

  }

  nsSMILInstanceTime* Begin();

  const nsSMILInstanceTime* End() const

  {

    MOZ_ASSERT(mBegin && mEnd,

               "Requesting End() on un-initialized instance time");

    return mEnd;

  }

  nsSMILInstanceTime* End();

  void SetBegin(nsSMILInstanceTime& aBegin);

  void SetEnd(nsSMILInstanceTime& aEnd);

  void Set(nsSMILInstanceTime& aBegin, nsSMILInstanceTime& aEnd)

  {

    SetBegin(aBegin);

    SetEnd(aEnd);

  }

  void FixBegin();

  void FixEnd();

  typedef nsTArray<RefPtr<nsSMILInstanceTime> > InstanceTimeList;

  void AddDependentTime(nsSMILInstanceTime& aTime);

  void RemoveDependentTime(const nsSMILInstanceTime& aTime);

  void GetDependentTimes(InstanceTimeList& aTimes);

  // Cue for assessing if this interval can be filtered

  bool IsDependencyChainLink() const;

private:

  RefPtr<nsSMILInstanceTime> mBegin;

  RefPtr<nsSMILInstanceTime> mEnd;

  // nsSMILInstanceTimes to notify when this interval is changed or deleted.

  InstanceTimeList mDependentTimes;

  // Indicates if the end points of the interval are fixed or not.

  //

  // Note that this is not the same as having an end point whose TIME is fixed

  // (i.e. nsSMILInstanceTime::IsFixed() returns true). This is because it is

  // possible to have an end point with a fixed TIME and yet still update the

  // end point to refer to a different nsSMILInstanceTime object.

  //

  // However, if mBegin/EndFixed is true, then BOTH the nsSMILInstanceTime

  // OBJECT returned for that end point and its TIME value will not change.

  bool mBeginFixed;

  bool mEndFixed;

};

#endif // NS_SMILINTERVAL_H_