/* 
   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_PARTICLE

#include "particle_engine.h"

#include "particle_system.h"
#include "particle_emitter.h"

#include "list.h"

using namespace std;

/**
   \brief standard constructor
*/
ParticleEngine::ParticleEngine () 
{
   this->setClassName ("ParticleEngine");

   this->systemList = new tList<ParticleSystem>;
   this->emitterList = new tList<ParticleEmitter>;
   this->connectionList = new tList<ParticleConnection>;
}

/**
   \brief the singleton reference to this class
*/
ParticleEngine* ParticleEngine::singletonRef = NULL;

/**
   \returns a Pointer to this Class
*/
ParticleEngine* ParticleEngine::getInstance(void)
{
  if (!ParticleEngine::singletonRef)
    ParticleEngine::singletonRef = new ParticleEngine();
  return ParticleEngine::singletonRef;
}

/**
   \brief standard destructor

*/
ParticleEngine::~ParticleEngine () 
{
  delete this->systemList;

  delete this->connectionList;

  ParticleEngine::singletonRef = NULL;
}

void ParticleEngine::addSystem(ParticleSystem* system)
{
  this->systemList->add(system);
}

void ParticleEngine::addEmitter(ParticleEmitter* emitter)
{
  this->emitterList->add(emitter);
}

/**
   \brief

   \todo header, check for double connections
*/
void ParticleEngine::addConnection(ParticleEmitter* emitter, ParticleSystem* system)
{
  // look, if we have already added this connection
  tIterator<ParticleConnection>* tmpConIt = connectionList->getIterator();
  ParticleConnection* tmpConnection = tmpConIt->nextElement();
  while(tmpConnection)
    {
      if (tmpConnection->emitter == emitter && tmpConnection->system == system)
	{
	  PRINTF(2)("Connection between Emitter and System already added\n");
	  delete tmpConIt;
	  return;
	}
      
      tmpConnection = tmpConIt->nextElement();
    }
  delete tmpConIt;
  


  ParticleConnection* tmpCon = new ParticleConnection;
  tmpCon->emitter = emitter;
  tmpCon->system = system;

  this->connectionList->add(tmpCon);
}


bool ParticleEngine::removeSystem(ParticleSystem* system)
{
  // remove any connections, that have this system within
  tIterator<ParticleConnection>* tmpConIt = connectionList->getIterator();
  ParticleConnection* tmpConnection = tmpConIt->nextElement();
  while(tmpConnection)
    {
      if (tmpConnection->system == system)
	this->breakConnection(tmpConnection);
      tmpConnection = tmpConIt->nextElement();
    }
  delete tmpConIt;

  // remove the System from the systemList.
  this->systemList->remove(system);
}

bool ParticleEngine::removeEmitter(ParticleEmitter* emitter)
{
  // remove any connections, that have this emitter within
  tIterator<ParticleConnection>* tmpConIt = connectionList->getIterator();
  ParticleConnection* tmpConnection = tmpConIt->nextElement();
  while(tmpConnection)
    {
      if (tmpConnection->emitter == emitter)
	this->breakConnection(tmpConnection);
      tmpConnection = tmpConIt->nextElement();
    }
  delete tmpConIt;

  // remove the emitter from the emitterList
  this->emitterList->remove(emitter);
}


bool ParticleEngine::breakConnection(ParticleEmitter* emitter, ParticleSystem* system)
{
  // look, if we have already added this connection
  tIterator<ParticleConnection>* tmpConIt = connectionList->getIterator();
  ParticleConnection* tmpConnection = tmpConIt->nextElement();
  while(tmpConnection)
    {
      if (tmpConnection->emitter == emitter && tmpConnection->system == system)
	this->breakConnection(tmpConnection);
      tmpConnection = tmpConIt->nextElement();
    }
  delete tmpConIt;  
}

bool ParticleEngine::breakConnection(ParticleConnection* connection)
{
  this->connectionList->remove(connection);
}


/**
   \brief this function ticks all the ParticleSystems, so an animation will flow
   \param dt passed since last tick
*/
void ParticleEngine::tick(float dt)
{
  // add new Particles to each System they are connected to.
  tIterator<ParticleConnection>* tmpConIt = connectionList->getIterator();
  ParticleConnection* tmpConnection = tmpConIt->nextElement();
  while(tmpConnection)
    {
      tmpConnection->emitter->tick(dt, tmpConnection->system);
      tmpConnection = tmpConIt->nextElement();
    }
  delete tmpConIt;
  

  // ticks all the ParticleSystems
  tIterator<ParticleSystem>* tmpIt = systemList->getIterator();
  ParticleSystem* tmpSys = tmpIt->nextElement();
  while(tmpSys)
    {
      tmpSys->tick(dt);
      tmpSys = tmpIt->nextElement();
    }
  delete tmpIt;
}


void ParticleEngine::draw(void)
{
  tIterator<ParticleSystem>* tmpIt = systemList->getIterator();
  ParticleSystem* tmpSys = tmpIt->nextElement();
  while(tmpSys)
    {
      tmpSys->draw();
      tmpSys = tmpIt->nextElement();
    }
  delete tmpIt;

}