/*
   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: ...
   co-programmer: ...
*/

//#define DEBUG_SPECIAL_MODULE DEBUG_MODULE_

#include "quick_animation.h"

#include <algorithm>



/**
 * @brief standard constructor
 * @param resolution the Resolution of the LookupTable
 */
QuickAnimation::QuickAnimation (unsigned int resolution)
{
  this->lookupValues.resize(resolution, 0.0f);
}

/**
 * @brief deletes all the deconstructor stuff
 */
QuickAnimation::~QuickAnimation ()
{ }

/**
 * @brief adds a new entry to the list of keyframes
 * @param position the position to add the key to
 * @param value the Value to set for the position
 * @returns false if the key existed already for a given position
 */
bool QuickAnimation::addKey(float position, float value)
{
  if (position > 1.0f || position < 0.0f)
  {
    printf("QuickAnimation::Position MUST BE between 0.0f and 1.0f\n");
    return false;
  }
  if(std::find(this->keyFrames.begin(), this->keyFrames.end(), position) != this->keyFrames.end())
  {
    printf("QuickAnimation:: key at position %f already added. Use changeValue instead\n", position);
    return false;
  }
  this->keyFrames.push_back(QuickKeyFrame(position, value));

  this->rebuild();
  return true;
}


/**
 * @brief changes an entry in the region of position
 * @param position the Position of an existing keyframe
 * @param region a deviation of the existing keyframe (like a delta in witch to search for)
 * @param value the new Value
 */
bool QuickAnimation::changeValueKey(unsigned int keyFrameNumber, float newValue)
{
  if (keyFrameNumber < this->keyFrames.size())
  {
    this->keyFrames[keyFrameNumber].value = newValue;
    this->rebuild();
    return true;
  }
  else
    return false;
}

/**
 * @brief changes an entry in the region of position
 * @param position the Position of an existing keyframe
 * @param region a deviation of the existing keyframe (like a delta in witch to search for)
 * @param value the new Value
 *
 * This Function adds a new KeyFrame at position with newValue, if none was found in region of position.
 */
bool QuickAnimation::changeValue(float position, float newValue, float region)
{
  int keyFrame = this->getKeyAt(position, region);
  if (keyFrame == -1)
    return this->addKey(position, newValue);
  else
    return this->changeValueKey(keyFrame, newValue);
}


/**
 * @brief removes the keyFrameNumber'th entry.
 * @param keyFrameNumber the n'th Keyframe to remove.
 * @returns true on success, false if keyFrameNumber did not exist.
 */
bool QuickAnimation::removeKey(unsigned int keyFrameNumber)
{
  if (keyFrameNumber < this->keyFrames.size())
  {
    this->keyFrames.erase(this->keyFrames.begin() + keyFrameNumber);
    this->rebuild();
    return true;
  }
  else
    return false;
}


/**
 * @brief removes a KeyFrame from the List.
 * @param position the Keyframe at position position will be erased.
 * @param region a deviation of the existing keyframe (like a delta in witch to search for)
 * @returns true on success, false if no KeyFrame was found.
 */
bool QuickAnimation::remove(float position, float region)
{
  int keyFrame = this->getKeyAt(position, region);
  if (keyFrame == -1)
    return false;
  else
    return this->removeKey(keyFrame);
}

/**
 * @brief moves the keyFrame keyFrameNumber to newPosition/newValue.
 * @param keyFrameNumber the n'th KeyFrame to move.
 * @param newPosition the new Position for the KeyFrame.
 * @param newValue the new Value for the KeyFrame.
 * @returns true on success, false if the KeyFrame did not exist.
 */
bool QuickAnimation::moveKey(unsigned int keyFrameNumber, float newPosition, float newValue)
{
  if (keyFrameNumber < this->keyFrames.size())
  {
    this->keyFrames[keyFrameNumber].position = newPosition;
    this->keyFrames[keyFrameNumber].value = newValue;
    this->rebuild();
    return true;
  }
  else
    return false;
}

/**
 * @brief moves the keyFrame keyFrameNumber to newPosition/value.
 * @param keyFrameNumber the n'th KeyFrame to move.
 * @param newPosition the new Position for the KeyFrame.
 * @returns true on success, false if the KeyFrame did not exist.
 */
bool QuickAnimation::moveKey(unsigned int keyFrameNumber, float newPosition)
{
  if (keyFrameNumber < this->keyFrames.size())
  {
    this->keyFrames[keyFrameNumber].position = newPosition;
    this->rebuild();
    return true;
  }
  else
    return false;
}

/**
 * @brief moves the keyFrame in the region of oldPosition to newPosition/newValue.
 * @param oldPosition the old Position for the KeyFrame.
 * @param newPosition the new Position for the KeyFrame.
 * @param newValue the new Value for the KeyFrame.
 * @param region the region around oldPosition to search for the KeyFrame.
 * @returns true on success, false if the KeyFrame was not found within the region of oldPosition.
 */
bool QuickAnimation::move(float oldPosition, float newPosition, float newValue, float region)
{
  int keyFrame = this->getKeyAt(oldPosition, region);
  if (keyFrame == -1)
    return false;
  else
    return this->moveKey(keyFrame, newPosition, newValue);
}

/**
 * @brief moves the keyFrame in the region of oldPosition to newPosition/Value.
 * @param oldPosition the old Position for the KeyFrame.
 * @param newPosition the new Position for the KeyFrame.
 * @param region the region around oldPosition to search for the KeyFrame.
 * @returns true on success, false if the KeyFrame was not found within the region of oldPosition.
 */
bool QuickAnimation::move(float oldPosition, float newPosition, float region)
{
  int keyFrame = this->getKeyAt(oldPosition, region);
  if (keyFrame == -1)
    return false;
  else
    return this->moveKey(keyFrame, newPosition);
}


/**
 * @brief searches for a Keyframe in the region of position
 * @param position the Keyframe at position position will searched for.
 * @param region a deviation of the existing keyframe (like a delta in witch to search for)
 * @returns the keyFrame on success, -1 on fault.
 */
int QuickAnimation::getKeyAt(float position, float region)
{
  for (unsigned int i = 0; i < this->keyFrames.size(); i++)
  {
    if (this->keyFrames[i].position + region/2.0 > position && this->keyFrames[i].position - region/2.0 < position)
      return i;
  }
  return -1;
}


/**
 * @brief rebuilds the QuickAnimation.
 */
void QuickAnimation::rebuild()
{
  // if we do not have any KeyFrames
  if (this->keyFrames.empty())
  {
    for (unsigned int i = 0; i < this->lookupValues.size(); i++)
      this->lookupValues[i] = 0.0f;
    return;
  }

  // Sort the List.
  std::sort(this->keyFrames.begin(), this->keyFrames.end(), QuickKeyFrame::sortPositionPredicate);

  // rebuild the lookup-table
  float sliceSize = 1.0f / this->lookupValues.size();
  unsigned int key = 0;
  float preVal = this->keyFrames[0].value;
  float prePos = this->keyFrames[0].position;

  float postVal = preVal;
  float postPos = 1.0;

  if (this->keyFrames.size() > 1)
  {
    postVal = this->keyFrames[1].value;
    postPos = this->keyFrames[1].position;
  }


  for (unsigned int i = 0; i < this->lookupValues.size(); i++)
  {
    float position = (float)i * sliceSize;

    // if we reach the Next KeyFrame
    if (position > postPos)
    {
      // if we have more KeyFrames.
      if (this->keyFrames.size() > ++key + 1)
      {
        preVal = this->keyFrames[key].value;
        prePos = this->keyFrames[key].position;
        postVal = this->keyFrames[key+1].value;
        postPos = this->keyFrames[key+1].position;
      }
      // otherwise we reached the last KeyFrame
      else
      {
        preVal = postVal;
        prePos = postPos;
        postPos = 1.0;
      }
    }
    this->lookupValues[i] = preVal + ( postVal - preVal) / (postPos - prePos) * (position - prePos);
  }
}

/**
 * @brief outputs some nice information about this class
 */
void QuickAnimation::debug() const
{
  printf("QuickAnim(KeyFrames:%d, Resolution:%d)::(position, value) ", this->keyFrames.size(), this->lookupValues.size());

  for (unsigned int i = 0; i < this->keyFrames.size(); i++)
    printf("(%0.2f, %0.2f)->", this->keyFrames[i].position, this->keyFrames[i].value);
  printf("\n");
}



/**
 * @brief compares two QuickKeyFrames with their positions.
 * @param key1 the first keyframe
 * @param key2 the second keyframe
 * @returns true, if the key1.position < key2.position.
 */
bool QuickAnimation::QuickKeyFrame::sortPositionPredicate(const QuickKeyFrame& key1, const QuickKeyFrame& key2)
{
  return (key1.position < key2.position);
}

/**
 * @brief compares two QuickKeyFrames with their values.
 * @param key1 the first keyframe
 * @param key2 the second keyframe
 * @returns true, if the key1.value < key2.value.
 */
bool QuickAnimation::QuickKeyFrame::sortValuePredicate(const QuickKeyFrame& key1, const QuickKeyFrame& key2)
{
  return (key1.value < key2.value);
}