package arc.box2d;

/**
 * A shape is used for collision detection. You can create a shape however you like. Shapes used for simulation in b2World are
 * created automatically when a b2Fixture is created. Shapes may encapsulate a one or more child shapes.
 * <p>
 * NOTE: YOU NEED TO DISPOSE SHAPES YOU CREATED YOURSELF AFTER YOU NO LONGER USE THEM! E.g. after calling body.createFixture();
 * @author mzechner
 */
public abstract class Shape{
    // @off
	/*JNI
#include <Box2D/Box2D.h>
	 */

    /**
     * Enum describing the type of a shape
     * @author mzechner
     */
    public enum Type{
        Circle, Edge, Polygon, Chain,
    }

    /** the address of the shape **/
    protected long addr;

    /**
     * Get the type of this shape. You can use this to down cast to the concrete shape.
     * @return the shape type.
     */
    public abstract Type getType();

    /** Returns the radius of this shape */
    public float getRadius(){
        return jniGetRadius(addr);
    }

    private native float jniGetRadius(long addr); /*
		b2Shape* shape = (b2Shape*)addr;
		return shape->m_radius;
	*/

    /** Sets the radius of this shape */
    public void setRadius(float radius){
        jniSetRadius(addr, radius);
    }

    private native void jniSetRadius(long addr, float radius); /*
		b2Shape* shape = (b2Shape*)addr;
		shape->m_radius = radius;
	*/

    /** Needs to be called when the shape is no longer used, e.g. after a fixture was created based on the shape. */
    public void dispose(){
        jniDispose(addr);
    }

    private native void jniDispose(long addr); /*
		b2Shape* shape = (b2Shape*)addr;
		delete shape;
	*/

    protected static native int jniGetType(long addr); /*
		b2Shape* shape = (b2Shape*)addr;
		switch(shape->m_type) {
		case b2Shape::e_circle: return 0;
		case b2Shape::e_edge: return 1;
		case b2Shape::e_polygon: return 2;
		case b2Shape::e_chain: return 3;
		default: return -1;
		}
	*/

    /** Get the number of child primitives. */
    public int getChildCount(){
        return jniGetChildCount(addr);
    }

    private native int jniGetChildCount(long addr); /*
		b2Shape* shape = (b2Shape*)addr;
		return shape->GetChildCount();
	*/

// /// Test a point for containment in this shape. This only works for convex shapes.
// /// @param xf the shape world transform.
// /// @param p a point in world coordinates.
// virtual bool TestPoint(const b2Transform& xf, const b2Vec2& p) const = 0;
//
// /// Cast a ray against this shape.
// /// @param output the ray-cast results.
// /// @param input the ray-cast input parameters.
// /// @param transform the transform to be applied to the shape.
// virtual bool RayCast(b2RayCastOutput* output, const b2RayCastInput& input, const b2Transform& transform) const = 0;
//
// /// Given a transform, compute the associated axis aligned bounding box for this shape.
// /// @param aabb returns the axis aligned box.
// /// @param xf the world transform of the shape.
// virtual void ComputeAABB(b2AABB* aabb, const b2Transform& xf) const = 0;
//
// /// Compute the mass properties of this shape using its dimensions and density.
// /// The inertia tensor is computed about the local origin.
// /// @param massData returns the mass data for this shape.
// /// @param density the density in kilograms per meter squared.
// virtual void ComputeMass(b2MassData* massData, float32 density) const = 0;
}
