#include "bullet-shape.h"
#include "bullet-space.h"

#include <btBulletDynamicsCommon.h>
#include <BulletCollision/CollisionShapes/btHeightfieldTerrainShape.h>



///////////
//  Utility
//

btCollisionShape*
to_bullet (Shape*   From)
{
  return (btCollisionShape*) From;
}


Shape*
to_bt3 (btCollisionShape*   From)
{
  return (Shape*) From;
}





extern "C"
{

/////////
//  Forge
//


Shape*
b3d_new_Box (Vector_3*   half_Extents)
{
  Shape*   Self = (Shape*)(btCollisionShape*) (new btBoxShape (btVector3 (half_Extents->x,
                                                                          half_Extents->y,
                                                                          half_Extents->z)));
  return Self;
}




Shape*
b3d_new_Capsule (Vector_2*   Radii,
                 Real        Height)
{
  Shape*   Self = (Shape*)(btCollisionShape*) (new btCapsuleShapeZ (Radii->x,
                                                                    Height));
  return Self;
}




Shape*
b3d_new_Cone (Real   Radius,
              Real   Height)
{
  Shape*   Self = (Shape*)(btCollisionShape*) (new btConeShape (Radius, Height));
  return Self;
}




Shape*
b3d_new_convex_Hull (Vector_3     Points[],
                     int          point_Count)
{
  btConvexHullShape*   bt_Hull = new btConvexHullShape ();

  for (int i = 0;   i < point_Count;   i++)
    {
      bt_Hull->addPoint (btVector3 (Points [i].x,
                                    Points [i].y,
                                    Points [i].z));
    }


  Shape*   Self = (Shape*)(btCollisionShape*) bt_Hull;
  return   Self;
}



  Shape*
  b3d_new_Mesh (Vector_3     Points[],
                int          point_Count,
		Triangle     Triangles[],
		int          triangle_Count)
  {
    btTriangleMesh* mesh = new btTriangleMesh();

    for (int i = 0;  i < triangle_Count;  i++)
      {
	btVector3                 bV1, bV2, bV3;

	bV1 [0] = Points [Triangles [i].a - 1].x;
	bV1 [1] = Points [Triangles [i].a - 1].y;
	bV1 [2] = Points [Triangles [i].a - 1].z;

	bV2 [0] = Points [Triangles [i].b - 1].x;
	bV2 [1] = Points [Triangles [i].b - 1].y;
	bV2 [2] = Points [Triangles [i].b - 1].z;

	bV3 [0] = Points [Triangles [i].c - 1].x;
	bV3 [1] = Points [Triangles [i].c - 1].y;
	bV3 [2] = Points [Triangles [i].c - 1].z;


	mesh->addTriangle (bV1, bV2, bV3);
      }


    btBvhTriangleMeshShape*   bt_Mesh = new btBvhTriangleMeshShape (mesh, true, true);

    Shape*   Self = (Shape*)(btCollisionShape*) bt_Mesh;
    return   Self;
  }




Shape*
b3d_new_Cylinder (Vector_3*   half_Extents)
{
  Shape*   Self = (Shape*)(btCollisionShape*) (new btCylinderShape (btVector3 (half_Extents->x,
                                                                               half_Extents->y,
                                                                               half_Extents->z)));
  return Self;
}




Shape*
b3d_new_Heightfield (int         Width,
                     int         Depth,
                     Real        Heights[],
                     Real        min_Height,
                     Real        max_Height,
                     Vector_3*   Scale)
{
  btCollisionShape*   Self = (btCollisionShape*) (new btHeightfieldTerrainShape (Width,      Depth,
                                                                                 Heights,
                                                                                 1.0,
                                                                                 min_Height, max_Height,
                                                                                 1,  PHY_FLOAT, 0));
  Self->setLocalScaling (btVector3 (Scale->x,
                                    Scale->y,
                                    Scale->z));
  return (Shape*) Self;;
}




Shape*
b3d_new_multiSphere (Vector_3*   Positions,
                     Real*       Radii,
                     int         sphere_Count)
{
  btVector3   bt_Positions [sphere_Count];

  for (int i=0;  i < sphere_Count;  i++)
    {
      bt_Positions [i][0] = Positions [i].x;
      bt_Positions [i][1] = Positions [i].y;
      bt_Positions [i][2] = Positions [i].z;
    }

  Shape*      Self = (Shape*)(btCollisionShape*) (new btMultiSphereShape (bt_Positions,
                                                                          Radii,
                                                                          sphere_Count));
  return Self;
}




Shape*
b3d_new_Plane (Vector_3*   Normal,
               Real       Offset)
{
  Shape*   Self = (Shape*)(btCollisionShape*) (new btStaticPlaneShape (btVector3 (Normal->x,
                                                                                  Normal->y,
                                                                                  Normal->z),
                                                                       Offset));
  return Self;
}



Shape*
b3d_new_Sphere (Real   Radius)
{
  Shape*   Self = (Shape*)(btCollisionShape*) (new btSphereShape (Radius));
  return Self;
}





//////////////
//  Attributes
//

void*
b3d_Shape_user_Data      (Shape*   Self)
{
  btCollisionShape*   the_Shape = to_bullet (Self);

  return the_Shape->getUserPointer();
}


void
b3d_Shape_user_Data_is   (Shape*   Self,   void*   Now)
{
  btCollisionShape*   the_Shape = to_bullet (Self);

  the_Shape->setUserPointer (Now);
}

} // extern "C"