/* -*- 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_SMILVALUE_H_

#define NS_SMILVALUE_H_

#include "nsISMILType.h"

#include "nsSMILNullType.h"

/**

 * Although objects of this type are generally only created on the stack and

 * only exist during the taking of a new time sample, that's not always the

 * case. The nsSMILValue objects obtained from attributes' base values are

 * cached so that the SMIL engine can make certain optimizations during a

 * sample if the base value has not changed since the last sample (potentially

 * avoiding recomposing). These nsSMILValue objects typically live much longer

 * than a single sample.

 */

class nsSMILValue

{

public:

  nsSMILValue() : mU(), mType(nsSMILNullType::Singleton()) { }

  explicit nsSMILValue(const nsISMILType* aType);

  nsSMILValue(const nsSMILValue& aVal);

  ~nsSMILValue()

  {

    mType->Destroy(*this);

  }

  const nsSMILValue& operator=(const nsSMILValue& aVal);

  // Move constructor / reassignment operator:

  nsSMILValue(nsSMILValue&& aVal);

  nsSMILValue& operator=(nsSMILValue&& aVal);

  // Equality operators. These are allowed to be conservative (return false

  // more than you'd expect) - see comment above nsISMILType::IsEqual.

  bool operator==(const nsSMILValue& aVal) const;

  bool operator!=(const nsSMILValue& aVal) const {

    return !(*this == aVal);

  }

  bool IsNull() const

  {

    return (mType == nsSMILNullType::Singleton());

  }

  nsresult Add(const nsSMILValue& aValueToAdd, uint32_t aCount = 1);

  nsresult SandwichAdd(const nsSMILValue& aValueToAdd);

  nsresult ComputeDistance(const nsSMILValue& aTo, double& aDistance) const;

  nsresult Interpolate(const nsSMILValue& aEndVal,

                       double aUnitDistance,

                       nsSMILValue& aResult) const;

  union {

    bool mBool;

    uint64_t mUint;

    int64_t mInt;

    double mDouble;

    struct {

      float mAngle;

      uint16_t mUnit;

      uint16_t mOrientType;

    } mOrient;

    int32_t mIntPair[2];

    float mNumberPair[2];

    void* mPtr;

  } mU;

  const nsISMILType* mType;

protected:

  void InitAndCheckPostcondition(const nsISMILType* aNewType);

  void DestroyAndCheckPostcondition();

  void DestroyAndReinit(const nsISMILType* aNewType);

};

#endif  // NS_SMILVALUE_H_