/*
   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: Patrick Boenzli
   co-programmer: ...
*/

#define DEBUG_SPECIAL_MODULE DEBUG_MODULE_COLLISION_REACTION



#include "collision.h"
#include "collision_event.h"
#include "collision_handle.h"
#include "cr_defs.h"

#include "cr_engine.h"

#include "debug.h"



ObjectListDefinition(CREngine);
/**
 * standard constructor
 */
CREngine::CREngine ()
  : BaseObject()
{
  this->registerObject(this, CREngine::_objectList);
   this->setName("CREngine");

   this->init();
}

/**
 *  the singleton reference to this class
 */
CREngine* CREngine::singletonRef = NULL;

/**
   @brief standard deconstructor
 */
CREngine::~CREngine ()
{
  CREngine::singletonRef = NULL;

  if( this->collisionsUnused.size() != CR_MAX_COLLISIONS)
    PRINTF(0)("CollisionReaction Error: Collision cache size missmatch: %i of %i\n", this->collisionsUnused.size(), CR_MAX_COLLISIONS);
  if( this->collisionEventsUnused.size() != CR_MAX_COLLISION_EVENTS)
    PRINTF(0)("CollisionReaction Error: CollisionEvent cache size missmatch: %i of %i\n", this->collisionEventsUnused.size(), CR_MAX_COLLISION_EVENTS);

  this->reset();

  std::vector<Collision*>::iterator it1 = this->collisionsUnused.begin();
  for(; it1 < this->collisionsUnused.end(); it1++)
    delete *it1;
  std::vector<CollisionEvent*>::iterator it2 = this->collisionEventsUnused.begin();
  for(; it2 < this->collisionEventsUnused.end(); it2++)
    delete *it2;

  this->collisionsUnused.clear();
  this->collisionEventsUnused.clear();
}

/**
 * inits the CREngine to a working state
 */
void CREngine::init()
{
  // create a list of Collision events (precaching)
  for( int i = 0; i < CR_MAX_COLLISIONS; i++)
    this->collisionsUnused.push_back(new Collision());
  for( int i = 0; i < CR_MAX_COLLISION_EVENTS; i++)
    this->collisionEventsUnused.push_back(new CollisionEvent());
}


/**
 * flushes the CollisionHandles and restores the CREngine to the initial state
 */
void CREngine::reset()
{
  // first clear all CollisionHandles

  std::vector<CollisionHandle*>::iterator it = this->collisionHandles.begin();
  for(; it < this->collisionHandles.end(); it++)
  {
    (*it)->reset();
    delete *it;
  }

  this->collisionHandles.clear();
}


/**
 * subscribes a WorldEntity for a CollisionReaction
 *  @param owner: the WE to subscribe
 *  @param type: the type of collision reaction to perform
 *  @return the newly created CollisionHandle
 */
CollisionHandle* CREngine::subscribeReaction(WorldEntity* owner, CRType type)
{
  CollisionHandle* ch = new CollisionHandle(owner, type);
  this->collisionHandles.push_back(ch);

  return ch;
}


/**
 * unsubscribe reaction from the reaction list
 *  @param collisionHandle the CollisionHandle to remove
 *  @param returns true if worked collrectly
 */
bool CREngine::unsubscribeReaction(CollisionHandle* collisionHandle)
{
  std::vector<CollisionHandle*>::iterator it;
  for( it = this->collisionHandles.begin(); it != this->collisionHandles.end(); it++)  {
    if( *it == collisionHandle) {
      this->collisionHandles.erase(it);
      delete collisionHandle;
      return true;
    }
  }
  return false;
}


/**
 * processes the collisions by calling the EventHandlers
 */
void CREngine::handleCollisions()
{
  std::vector<CollisionHandle*>::iterator it;
  for( it = this->collisionHandles.begin(); it != this->collisionHandles.end(); it++)
  {
    if( !(*it)->isDispatched() || (*it)->isContinuousPoll())  //does it have any collisions to report at all
    {
      (*it)->handleCollisions();
    }
  }
  this->flushCollisions();
}


/**
 * flushes all the collision lists and puts them to their initial state
 */
void CREngine::flushCollisions()
{
  std::vector<Collision*>::iterator it1 = this->collisionsUsed.begin();
  for(; it1 < this->collisionsUsed.end(); it1++)
    this->collisionsUnused.push_back(*it1);

  std::vector<CollisionEvent*>::iterator it2 = this->collisionEventsUsed.begin();
  for(; it2 < this->collisionEventsUsed.end(); it2++)
    this->collisionEventsUnused.push_back(*it2);

  this->collisionsUsed.clear();
  this->collisionEventsUsed.clear();
}


void CREngine::debug()
{

}