// -*- c++ -*-

 /**

 Implementation of a bounding box of plainvectors.

 */

 #ifndef HUGO_BOUNDINGBOX_H

 #define HUGO_BOUNDINGBOX_H

 #include <xy.h>

 namespace hugo {

   template<typename T>

     class BoundingBox {

       xy<T> bottomleft, topright;

       bool _empty;

     public:

       ///Default constructor: an empty bounding box

       BoundingBox() { _empty = true; }

       ///Constructing the instance from one point

       BoundingBox(xy<T> a) { bottomleft=topright=a; _empty = false; }

       ///Is there any point added

       bool empty() const {

 	return _empty;

       }

       ///Gives back the bottom left corner (if the bounding box is empty, then the return value is not defined) 

       xy<T> bottomLeft() const {

 	return bottomleft;

       };

       ///Gives back the top right corner (if the bounding box is empty, then the return value is not defined) 

       xy<T> topRight() const {

 	return topright;

       };

       ///Checks whether a point is inside a bounding box

       bool inside(const xy<T>& u){

 	if (_empty)

 	  return false;

 	else{

 	  return ((u.x-bottomleft.x)*(topright.x-u.x) >= 0 &&

 		  (u.y-bottomleft.y)*(topright.y-u.y) >= 0 );

 	}

       }

       ///Increments a bounding box with a point

       BoundingBox& operator +=(const xy<T>& u){

 	if (_empty){

 	  bottomleft=topright=u;

 	  _empty = false;

 	}

 	else{

 	  if (bottomleft.x > u.x) bottomleft.x = u.x;

 	  if (bottomleft.y > u.y) bottomleft.y = u.y;

 	  if (topright.x < u.x) topright.x = u.x;

 	  if (topright.y < u.y) topright.y = u.y;

 	}

 	return *this;

       };

       ///Sums a bounding box and a point

       BoundingBox operator +(const xy<T>& u){

 	BoundingBox b = *this;

 	return b += u;

       };

       ///Increments a bounding box with an other bounding box

       BoundingBox& operator +=(const BoundingBox &u){

 	if ( !u.empty() ){

 	  *this += u.bottomLeft();

 	  *this += u.topRight();

 	}

 	return *this;

       };

       ///Sums two bounding boxes

       BoundingBox operator +(const BoundingBox& u){

 	BoundingBox b = *this;

 	return b += u;

       };

     };//class BoundingBox

 } //namespace hugo

 #endif //HUGO_BOUNDINGBOX_H