/*
   orxonox - the future of 3D-vertical-scrollers

   Copyright (C) 2004 orx

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   ### File Specific:
   main-programmer: Benjamin Grauer
   co-programmer: ...
*/


/*! 
    \file t_animation.h
*/

#ifndef _T_ANIMATION_H
#define _T_ANIMATION_H

#include "animation.h"

//! A Class to handle some animation for single floated values.
template<class T> class tAnimation : public Animation
{
 public:
  tAnimation(T* object = NULL, void (T::*funcToAnim)(float) = NULL);
  virtual ~tAnimation();

  virtual void rewind();

  void setFuncToAnim(T* object, void (T::*funcToAnim)(float));
  void addKeyFrame(float value, float duration, ANIM_FUNCTION animFunc = ANIM_LINEAR);

  virtual void tick(float dt);

  // animation functions
  void setAnimFunc(ANIM_FUNCTION animFunc);

 private:

  float constant(float timePassed) const;
  float linear(float timePassed) const;
  float sine(float timePassed) const;
  float cosine(float timePassed) const;
  float exp(float timePassed) const;
  float negExp(float timePassed) const;
  float quadratic(float timePassed) const;
  float random(float timePassed) const;


  //  ANIM_FUNCTION animFunc;
  float (tAnimation<T>::*animFunc)(float) const;
  KeyFrameF* currentKeyFrame;
  KeyFrameF* nextKeyFrame;
  tList<KeyFrameF>* keyFrameList;

  float expFactor;
  T* object;
  void (T::*funcToAnim)(float);
};



/**
   \brief standard constructor

*/
template<class T>
tAnimation<T>::tAnimation (T* object, void (T::*funcToAnim)(float)) 
{
  // create a new List
  this->keyFrameList = new tList<KeyFrameF>();
  KeyFrameF* tmpKeyFrame = new KeyFrameF;
  tmpKeyFrame->value = 0.0;
  tmpKeyFrame->duration = 1.0;
  keyFrameList->add(tmpKeyFrame);

  this->currentKeyFrame = tmpKeyFrame;
  this->nextKeyFrame = tmpKeyFrame;

  this->animFunc = &tAnimation<T>::linear;

  this->setFuncToAnim(object, funcToAnim);
}


/**
   \brief standard deconstructor

*/
template<class T>
tAnimation<T>::~tAnimation () 
{
  // delete all the KeyFrames
  tIterator<KeyFrameF>* itKF = keyFrameList->getIterator();
  KeyFrameF*  enumKF = itKF->nextElement();
  while (enumKF)
    {
      delete enumKF;
      enumKF = itKF->nextElement();
    }
  delete itKF;
  delete this->keyFrameList;

}

template<class T>
void tAnimation<T>::rewind(void)
{
  this->currentKeyFrame = keyFrameList->firstElement();
  this->nextKeyFrame = keyFrameList->nextElement(keyFrameList->firstElement());
  this->localTime = 0.0;
}

template<class T>
void tAnimation<T>::setFuncToAnim(T* object, void (T::*funcToAnim)(float))
{
  this->baseObject = this->object = object;
  this->funcToAnim = funcToAnim;
}

template<class T>
void tAnimation<T>::addKeyFrame(float value, float duration, ANIM_FUNCTION animFunc)
{
  // some small check
  if (duration <= 0.0)
    duration = 1.0;

  KeyFrameF* tmpKeyFrame;
    
  if (bHasKeys)
    {
      tmpKeyFrame = new KeyFrameF;
      if (this->currentKeyFrame == this->nextKeyFrame)
	this->nextKeyFrame = tmpKeyFrame;
      this->keyFrameList->add(tmpKeyFrame);

    }
  else
    {
      tmpKeyFrame = this->keyFrameList->firstElement();
      bHasKeys = true;
      this->setAnimFunc(animFunc);
    }
  tmpKeyFrame->value = value;
  tmpKeyFrame->duration = duration;
  tmpKeyFrame->animFunc = animFunc;
}


template<class T>
void tAnimation<T>::tick(float dt)
{
  if (this->bRunning)
    {
      this->localTime += dt;
      if (localTime >= this->currentKeyFrame->duration)
	{
	  // switching to the next Key-Frame
	  this->localTime -= this->currentKeyFrame->duration;

	  this->currentKeyFrame = this->nextKeyFrame;
	  // checking, if we should still Play the animation
	  if (this->currentKeyFrame == this->keyFrameList->lastElement())
	    {
	      switch (this->postInfinity)
		{
		case ANIM_INF_CONSTANT:
		  this->bRunning = false;
		  break;
		case ANIM_INF_REWIND:
		  break;
		}
	    }
	  this->nextKeyFrame = this->keyFrameList->nextElement(this->nextKeyFrame);
	  printf("%p from:%f to:%f\n", this->currentKeyFrame,this->currentKeyFrame->value, this->nextKeyFrame->value);
	  this->setAnimFunc(this->currentKeyFrame->animFunc);	  
	}
      
      (this->object->*(funcToAnim))((this->*animFunc)(this->localTime));
    }
}


template<class T>
void tAnimation<T>::setAnimFunc(ANIM_FUNCTION animFunc)
{
  switch (animFunc)
    {
    default:
    case ANIM_CONSTANT:
      this->animFunc = &tAnimation<T>::constant;
      break;
    case ANIM_LINEAR:
      this->animFunc = &tAnimation<T>::linear;
      break;
    case ANIM_SINE:
      this->animFunc = &tAnimation<T>::sine;
      break;
    case ANIM_COSINE:
      this->animFunc = &tAnimation<T>::cosine;
      break;
    case ANIM_EXP:
      this->animFunc = &tAnimation<T>::exp;
      break;
    case ANIM_NEG_EXP:
      {
	this->animFunc = &tAnimation<T>::negExp;
	float d = fabs(this->currentKeyFrame->value - this->nextKeyFrame->value);
	expFactor =  - 1.0 / this->currentKeyFrame->duration * logf(DELTA_X);
	break;
      }
    case ANIM_QUADRATIC:
      this->animFunc = &tAnimation<T>::quadratic;
      break;
    case ANIM_RANDOM:
      this->animFunc = &tAnimation<T>::random;
      break;
    }
}


// animation functions
template<class T>
float tAnimation<T>::random(float timePassed) const
{
  return (float)rand()/(float)RAND_MAX;
}

template<class T>
float tAnimation<T>::constant(float timePassed) const
{
  return this->currentKeyFrame->value;
}

template<class T>
float tAnimation<T>::linear(float timePassed) const 
{
  return this->currentKeyFrame->value + (this->nextKeyFrame->value - this->currentKeyFrame->value) 
    * (timePassed / this->currentKeyFrame->duration);
  //  PRINTF(0)("value is %f, %p %p\n", val, this->currentKeyFrame, this->nextKeyFrame);
  //  return val;
}

template<class T>
float tAnimation<T>::sine(float timePassed) const
{
  float d = this->currentKeyFrame->value - this->nextKeyFrame->value;
  float e = 0.5 * d * (1 - cos(M_PI * timePassed / this->currentKeyFrame->duration));
  return this->currentKeyFrame->value - e;
  /*
  return his->currentKeyFrame->value - (this->nextKeyFrame->value - this->currentKeyFrame->value)
    * sin(timePassed / this->currentKeyFrame->duration * M_PI);
  */
}

template<class T>
float tAnimation<T>::cosine(float timePassed) const
{
  float d = this->currentKeyFrame->value - this->nextKeyFrame->value;
  float e = 0.5 * d * (sin(M_PI * timePassed / this->currentKeyFrame->duration));
  if( timePassed > 0.5*this->currentKeyFrame->duration) e = (d - e);
  return this->currentKeyFrame->value - e;
  /*
  return this->currentKeyFrame->value - (this->nextKeyFrame->value - this->currentKeyFrame->value)
    * cos(timePassed / this->currentKeyFrame->duration * M_PI);
  */
}

template<class T>
float tAnimation<T>::exp(float timePassed) const
{
}

template<class T>
float tAnimation<T>::negExp(float timePassed) const
{
  float d = this->currentKeyFrame->value - this->nextKeyFrame->value;
  float e = d * (1.0 - expf(- timePassed * expFactor));
  return  this->currentKeyFrame->value - e;
}

template<class T>
float tAnimation<T>::quadratic(float timePassed) const
{

}


#endif /* _T_ANIMATION_H */