/* 
   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: Benjamin Grauer
   
   bensch: renamed the file
*/

#define DEBUG_SPECIAL_MODULE DEBUG_MODULE_PHYSICS

#include "physics_interface.h"
#include "list.h"
#include "string.h"
#include "stdincl.h"

using namespace std;


/**
   \brief standard constructor
*/
PhysicsInterface::PhysicsInterface () 
{
   this->setClassName ("PhysicsInterface");
   this->mass = 0;
   this->massChildren = 0;
   this->forceSum = Vector(0, 0, 0);
}


/**
   \brief standard deconstructor

*/
PhysicsInterface::~PhysicsInterface () 
{
  // delete what has to be deleted here
}

void PhysicsInterface::recalcMass()
{
	float massSum = 0;
	
	tIterator<PNode>* iterator = this->children->getIterator();
	PNode* pn = iterator->nextElement();
	while( pn != NULL) 
    { 
    	// todo: find out if children are PhysicsInterface in an efficient way
    	if (strcmp( pn->getClassName(), "PhysicsInterface")) {
			massSum += ((PhysicsInterface*)pn)->getTotalMass();
    	}
      pn = iterator->nextElement();
    }
	delete iterator;
	
	if (massSum != this->massChildren ) {
		this->massChildren = massSum;
		if (strcmp( parent->getClassName(), "PhysicsInterface"))
			((PhysicsInterface*)parent)->recalcMass();
	} else {
		this->massChildren = massSum;
	}
}
	
	
void PhysicsInterface::addForce( Vector force )
{
	forceSum += force;
}

void PhysicsInterface::addForce(Vector force, Vector grip)
{
	// add central force
	forceSum += force;
	// add momentum
	// todo: some vector math
}
	
void PhysicsInterface::tick( float dt )
{
	Vector acc = forceSum / ( massChildren + mass );
	// todo: introduce kinematics
}