/*
   model/collisionmesh.h
   This file is part of the Osirion project and is distributed under
   the terms of the GNU General Public License version 2
*/

#ifndef __INCLUDED_MODEL_COLLISIONMESH_H__
#define __INCLUDED_MODEL_COLLISIONMESH_H__

#include "math/mathlib.h"
#include "model/fragment.h"

#include "BulletCollision/CollisionShapes/btTriangleMesh.h"

#include <string>
#include <map>

namespace model
{

/**
 * @brief a collection of triangles, representing the collision geometry of a model
 * A CollisionModel consists of a number of collisionmeshes.
 * */
class CollisionMesh
{
public:

	/// type definition for the collisionmesh registry
	typedef std::list<CollisionMesh *> Registry;

	CollisionMesh();
	
	/// copy constructor
	CollisionMesh(const CollisionMesh &other);

	~CollisionMesh();

	/* ---- inspectors ----------------------------------------- */

	/**
	 * @brief the number of triangles in the collision mesh
	 */
	inline size_t size() const {
		return collisionmesh_size;
	}
	
	/**
	 * @brief the bullet triangle mesh object
	 */
	inline btTriangleMesh *triangles() {
		return collisionmesh_triangles;
	}

	/**
	 * @brief location of the mesh within the parent model
	 * location() is a point in collision model coordinate space
	 * that indicates the (0,0,0) location of this mesh.
	 * The worldspawn mesh should have location (0,0,0)
	 * */
	inline const math::Vector3f &location() const {
		return collisionmesh_location;
	}

	/**
	 * @brief transformation axis
	 * For normal groups, this is the rotation matrix of the mesh
	 * For rotating groups axis->forward() is the axis of the rotation.
	 * For movers, axis->forward() is the axis of movement. 	
	 * */
	inline const math::Axis & axis() const {
		return collisionmesh_axis;
	}
	
	inline const float speed() const {
		return collisionmesh_speed;
	}
	
	inline const float distance() const {
		return collisionmesh_distance;
	}

	inline const float scale() const {
		return collisionmesh_scale;
	}

	inline const FragmentGroup::Type type() const {
		return collisionmesh_type;
	}

	/* ---- mutators ------------------------------------------- */

	/**
	 * @brief change the group type
	 * */
	inline void set_type(const FragmentGroup::Type type) {
		collisionmesh_type = type;
	}

	inline void set_location(const math::Vector3f &location) {
		collisionmesh_location.assign(location);
	}
	
	inline void set_axis(const math::Axis &axis) {
		collisionmesh_axis.assign(axis);
	}
	
	/**
	 * @brief apply FragmentGroup parameters to the mesh
	 * This method applies the fragmentgroups type, location, axis, distance, speed and scale
	 * to the collision mesh
	 */
	void set_params(const FragmentGroup *group);
	
	/**
	 * @brief movement speed
	 * For rotating meshes this is the number of degrees per second
	 * For movers, this is the speed in units per second
	 */
	inline void set_speed(const float speed) {
		collisionmesh_speed = speed;
	}
	
	inline void set_distance(const float distance) {
		collisionmesh_distance = distance;
	}

	inline void set_scale(const float scale) {
		collisionmesh_scale = scale;
	}
	
	/**
	 *  @brief add a triangle to the collision mesh
	 */
	void add_triangle(const math::Vector3f & v0, const math::Vector3f & v1, const math::Vector3f & v2);

private:

	/// the materials registry
	static Registry			collisionmesh_registry;
	static bool			collisionmesh_initialized;
	
	size_t				collisionmesh_size;
	btTriangleMesh			*collisionmesh_triangles;
	FragmentGroup::Type		collisionmesh_type;
	
	math::Vector3f			collisionmesh_location;
	math::Axis			collisionmesh_axis;
	
	float				collisionmesh_speed;
	float				collisionmesh_scale;
	float				collisionmesh_distance;

	bool				collisionmesh_owns_triangles;
};

} // namespace model

#endif // __INCLUDED_MODEL_COLLISIONMESH_H__