//! "sju" Physics Engine for MotorJ
/*!
 *
 * sju Physics Engine, Physics system for MotorJ
 *
 * Handles collision tests and responses between several kinds of geometries,
 * as well as attraction/repulsion forces, friction fields, etc.
 *
 */
/* Copyright (C) 2008-2010  Alejandro Valenzuela Roca, <lanjoe9 at mexinetica NOSPAMPLEASE dot com>
 *
 * This file is part of MotorJ, a free framework for videogame creation.
 * <http://motorj.mexinetica.com/ >
 * <http://wiki.lidsol.net/wiki/index.php?title=MotorJ >
 *
 * MotorJ is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * MotorJ is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with MotorJ.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef SJUENGINE_CLASS_H
#define SJUENGINE_CLASS_H

#include "sjuengine-types.h"
#include "physicalobject-class.h"
#include "pmesh-class.h"
#include "paabb-class.h"
#include "support.h"
#include "collisions.h"
#include <list>

// For some parallelisation tricks
#ifdef PC_SDL
#include <SDL/SDL_thread.h>
#endif


//! Update block - for internal concurrent calculation usage
typedef struct {
    std::list<IPhysicalObject *>::iterator start;
    std::list<IPhysicalObject *>::iterator  stop;
    std::list<IPhysicalObject *> objects;
    float t_elapsed;
    int numThread;
} mjUpdateBlock;


//! "sju" Physics Engine for MotorJ
/*!
 *
 * sju Physics Engine, Physics system for MotorJ
 *
 * Handles collision tests and responses between several kinds of geometries,
 * as well as attraction/repulsion forces, friction fields, etc.
 *
 */
class mjPhysics
{
	public:
	 mjPhysics();

	 //! Update (must be run on each Universe update method)
	 void Update(float t_elapsed);

	 //! Add a previously instatiated object to the physical simulation
	 void AddObject(IPhysicalObject * object);
	 //! Remove an object from the physical simulation
	 bool RemoveObject(IPhysicalObject * physObject);

	 //! Apply a unique, temporary effect to an object
 	 void ApplyEffect(IPhysicalObject * object, vector3 & effect, vector3 & pointOfAction, sjuPETypes effectType, IPhysicalObject* interactionObject);

	 //! Remove all effects for specified object
	 void RemoveEffectsForObject(IPhysicalObject* object);

	 //! Set the gravity acceleration
	 void SetGravity(vector3 & g);
	 void SetGravity(float y);
	 void SetGravity(float x, float y, float z);

	 //! Set the drag factor (the medium's opposition to object movement)
	 void SetDragFactor(float newDragFactor);

	 //! Set the direction for point/sphere vs surface test (NULL = triangle's own normal)
	 void SetRayTrDir(vector3* dir);

	 //! Set the gravitational constant, G (not to be confused with gravity! See SetGravity)
	 void SetGravitationConstant(float G);

	 //! Set the Coulomb constant, ke
	 void SetCoulombConstant(float ke);

	 //! Coulomb force radius
	 void SetCoulombFRadius(float radius);

	 //! Attraction-repulsion model (normal or constant)
	 sjuCoulombModel coulombModel;

	 //! Object list - alter only if you know what you're doing
	 std::list<IPhysicalObject *> objects;
	 //list_header objects;
	 //! Mesh list - alter only if you know what you're doing
	 std::list<pMesh *> meshes;
	//list_header meshes;

	private:

	 //list_header forces;
	 std::list<pEffect *> forces;
	 //list_header temp_effects;
	 std::list<pEffect *> temp_effects;
	 float dragFactor;
	 vector3 gravity;
	 float gravitationConstant;
	 float coulombConstant;
	 float coulombFRadius;
	 vector3* rayTrDir;

	 #ifdef PC_SDL
	 // Multi-processor variables
	 #define MAX_PROCESSORS 2
	 SDL_Thread **update_children;
	 mjUpdateBlock* update_blocks;
     #endif


};

int thread_Update(void* data);
#endif