#ifndef __INTERSECTABLE_H
#define __INTERSECTABLE_H

#include "AxisAlignedBox3.h"
#include "Pvs.h"
#include <set>

namespace GtpVisibilityPreprocessor {

struct VssRayContainer;
class KdLeaf;

class Intersectable {
public:
  // last mail id -> warning not thread safe!
  // both mailId and mailbox should be unique for each thread!!!
  static int sMailId;
  static int sReservedMailboxes;
  int mMailbox;
  
  /// unique object Id
  int mId;
  
  /// universal counter
  int mCounter;
	
  /// object based pvs
  KdPvs mKdPvs;
  
  ViewCellPvs mViewCellPvs;

  /// kd leaves that this intersectable belongs to
  set<KdLeaf *> mKdLeaves;

  enum { MESH_INSTANCE, TRANSFORMED_MESH_INSTANCE, SPHERE, VIEW_CELL, OGRE_MESH_INSTANCE };
  
  Intersectable():mMailbox(0) {}

	void SetId(const int id) { mId = id; }
	int GetId() { return mId; }
	

	static void NewMail(const int reserve = 1) {
		sMailId += sReservedMailboxes;
		sReservedMailboxes = reserve;
	}
	
	void Mail() { mMailbox = sMailId; }
	bool Mailed() const { return mMailbox == sMailId; }

	void Mail(const int mailbox) { mMailbox = sMailId + mailbox; }
	bool Mailed(const int mailbox) const { return mMailbox == sMailId + mailbox; }

	int IncMail() { return ++mMailbox - sMailId; }


    virtual AxisAlignedBox3 GetBox() const = 0;
	virtual int CastRay(GtpVisibilityPreprocessor::Ray &ray) = 0;
	
	virtual bool IsConvex() const = 0;
	virtual bool IsWatertight() const = 0;
	virtual float IntersectionComplexity() = 0;
  
	virtual int NumberOfFaces() const = 0;
	virtual int Type() const = 0;

	virtual int GetRandomSurfacePoint(Vector3 &point, Vector3 &normal) = 0;

	virtual int GetRandomVisibleSurfacePoint(Vector3 &point,
											 Vector3 &normal,
											 const Vector3 &viewpoint,
											 const int maxTries) = 0;
  
	virtual ostream &Describe(ostream &s) = 0;
	
	virtual int GenerateSilhouetteRays(const int nrays,
									   const AxisAlignedBox3 &originBox,
									   const AxisAlignedBox3 &directionBox, VssRayContainer &rays) 
	{
		return 0;
	}

	static bool GreaterCounter(const Intersectable *a,
							 const Intersectable *b) 
	{
		return a->mCounter > b->mCounter;
	}
};

}

#endif