// This may look like C code, but it's really -*- C++ -*-

/*

 * Copyright (C) 2011 Emweb bv, Herent, Belgium.

 *

 * See the LICENSE file for terms of use.

 */

#ifndef WANIMATION_H_

#define WANIMATION_H_

#include <Wt/WGlobal.h>

namespace Wt {

/*! \brief An enumeration describing an animation effect

 *

 * An animation effect can be the combination of a motion and an optional

 * fade effect, e.g:

 * \code

 *  AnimationEffect::SlideInFromRight

 *  AnimationEffect::SlideInFromTop | AnimationEffect::Fade

 * \endcode

 *

 * You can specify only one motion effect.

 *

 * \sa setEffects()

 */

enum class AnimationEffect {

  SlideInFromLeft = 0x1,   //!< Slides right to show, left to hide

  SlideInFromRight = 0x2,  //!< Slides left to show, right to hide

  SlideInFromBottom = 0x3, //!< Slides up to show, down to hide

  SlideInFromTop = 0x4,    //!< Slides down to show, up to hide

  Pop = 0x5,               //!< Pops up to show, pops away to hide

  Fade = 0x100             //!< Fade effect

};

/*! \brief A timing function

 *

 * The timing function defines how the animation effects are animated

 * during the total duration of the animation.

 */

enum class TimingFunction {

  Ease,        //!< Slow start and slow finish

  Linear,      //!< Linear throughout

  EaseIn,      //!< Slow start

  EaseOut,     //!< Slow finish

  EaseInOut,   //!< Slow start and even slower finish

  CubicBezier  //!< (Currently unsupported)

};

/*! \class WAnimation Wt/WAnimation.h Wt/WAnimation.h

 *  \brief A value class that defines a transition effect.

 *

 * This class defines an animation used as a transition to show or

 * hide a widget.

 *

 * The animation can be defined as a motion effect (e.g. sliding in or

 * out), optionally combined with a fade effect. A timing function

 * defines how the effects(s) are animated during the total duration of

 * the animation.

 *

 * \sa WWidget::animateShow(), WWidget::animateHide(), WWidget::setHidden()

 */

class WT_API WAnimation

{

public:

  /*! \brief Typedef for enum Wt::AnimationEffect */

  typedef AnimationEffect Effect;

  /*! \brief Default constructor.

   *

   * Creates an animation that actually represent <i>no</i> animation.

   * (effects() == 0).

   */

  WAnimation();

  /*! \brief Creates an animation.

   *

   * An animation is created with given effects, timing and duration.

   */

  WAnimation(WFlags<AnimationEffect> effects,

             TimingFunction timing = TimingFunction::Linear,

             int duration = 250);

#ifdef WT_TARGET_JAVA

  /*! \brief Creates an animation.

   *

   * An animation is created with one effect, timing and duration.

   */

  WAnimation(AnimationEffect effect,

             TimingFunction timing = TimingFunction::Linear,

             int duration = 250);

  /*! \brief Creates an animation.

   *

   * An animation is created with two effects (a motion and Fade).

   */

  WAnimation(AnimationEffect effect1, AnimationEffect effect2,

             TimingFunction timing = TimingFunction::Linear,

             int duration = 250);

  /*! \brief Clone method.

   *

   * Clones this animation object.

   */

  WAnimation clone() const;

#endif

  /*! \brief Sets the animation effects.

   *

   * A motion effect (\link AnimationEffect::SlideInFromLeft

   * SlideInFromLeft\endlink, \link AnimationEffect::SlideInFromRight

   * SlideInFromRight\endlink, \link AnimationEffect::SlideInFromBottom

   * SlideInFromBottom\endlink, \link AnimationEffect::SlideInFromTop

   * SlideInFromTop\endlink or \link AnimationEffect::Pop Pop\endlink) can be combined

   * with a fade effect (\link AnimationEffect::Fade Fade\endlink).

   *

   * When effects are 0, the animation does not actually specify an

   * animation, but instead an instant transition.

   */

  void setEffects(WFlags<AnimationEffect> effects);

  /*! \brief Returns animation effects.

   *

   * \sa setEffects()

   */

  WFlags<AnimationEffect> effects() const { return effects_; }

  /*! \brief Comparison operator.

   *

   * Returns \c true if the transitions are exactly the same.

   */

  bool operator==(const WAnimation& other) const;

  /*! \brief Comparison operator.

   *

   * Returns \c true if the transitions are different.

   */

  bool operator!=(const WAnimation& other) const;

  /*! \brief Sets the duration.

   *

   * The default animation duration is 250 ms.

   *

   * \sa duration()

   */

  void setDuration(int msecs);

  /*! \brief Returns the duration.

   *

   * \sa setDuration()

   */

  int duration() const { return duration_; }

  /*! \brief Sets a timing function.

   *

   * The default timinig function is TimingFunction::Linear.

   */

  void setTimingFunction(TimingFunction function);

  /*! \brief Returns the timing function.

   *

   * \sa setTimingFunction()

   */

  TimingFunction timingFunction() const { return timing_; }

  /*

  void setTimingFunction(double x1, double y1, double x2, double y2);

  const double[] timingFunction();

  */

  /*! \brief Returns whether the animation is empty.

   *

   * An animation is empty (meaning the transition is instant), if the

   * duration is 0, or if no effects are defined.

   */

  bool empty() const;

private:

  WFlags<AnimationEffect> effects_;

  TimingFunction          timing_;

  int                     duration_;

};

W_DECLARE_OPERATORS_FOR_FLAGS(AnimationEffect)

}

#endif // WANIMATION_H_