/* -*- C++ -*-

  * src/lemon/xy.h - Part of LEMON, a generic C++ optimization library

  *

  * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

  * (Egervary Research Group on Combinatorial Optimization, EGRES).

  *

  * Permission to use, modify and distribute this software is granted

  * provided that this copyright notice appears in all copies. For

  * precise terms see the accompanying LICENSE file.

  *

  * This software is provided "AS IS" with no warranty of any kind,

  * express or implied, and with no claim as to its suitability for any

  * purpose.

  *

  */

 #ifndef LEMON_XY_H

 #define LEMON_XY_H

 #include <iostream>

 ///\ingroup misc

 ///\file

 ///\brief A simple two dimensional vector and a bounding box implementation 

 ///

 /// The class \ref lemon::xy "xy" implements

 ///a two dimensional vector with the usual

 /// operations.

 ///

 /// The class \ref lemon::BoundingBox "BoundingBox" can be used to determine

 /// the rectangular bounding box a set of \ref lemon::xy "xy"'s.

 ///

 ///\author Attila Bernath

 namespace lemon {

   /// \addtogroup misc

   /// @{

   /// A simple two dimensional vector (plainvector) implementation

   /// A simple two dimensional vector (plainvector) implementation

   ///with the usual vector

   /// operators.

   ///

   ///\author Attila Bernath

   template<typename T>

     class xy {

     public:

       typedef T Value;

       T x,y;     

       ///Default constructor

       xy() {}

       ///Constructing the instance from coordinates

       xy(T a, T b) : x(a), y(b) { }

       ///Conversion constructor

       template<class TT> xy(const xy<TT> &p) : x(p.x), y(p.y) {}

       ///Gives back the square of the norm of the vector

       T normSquare() const {

 	return x*x+y*y;

       }

       ///Increments the left hand side by u

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

 	x += u.x;

 	y += u.y;

 	return *this;

       }

       ///Decrements the left hand side by u

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

 	x -= u.x;

 	y -= u.y;

 	return *this;

       }

       ///Multiplying the left hand side with a scalar

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

 	x *= u;

 	y *= u;

 	return *this;

       }

       ///Dividing the left hand side by a scalar

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

 	x /= u;

 	y /= u;

 	return *this;

       }

       ///Returns the scalar product of two vectors

       T operator *(const xy<T>& u) const {

 	return x*u.x+y*u.y;

       }

       ///Returns the sum of two vectors

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

 	xy<T> b=*this;

 	return b+=u;

       }

       ///Returns the neg of the vectors

       xy<T> operator-() const {

 	xy<T> b=*this;

 	b.x=-b.x; b.y=-b.y;

 	return b;

       }

       ///Returns the difference of two vectors

       xy<T> operator-(const xy<T> &u) const {

 	xy<T> b=*this;

 	return b-=u;

       }

       ///Returns a vector multiplied by a scalar

       xy<T> operator*(const T &u) const {

 	xy<T> b=*this;

 	return b*=u;

       }

       ///Returns a vector divided by a scalar

       xy<T> operator/(const T &u) const {

 	xy<T> b=*this;

 	return b/=u;

       }

       ///Testing equality

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

 	return (x==u.x) && (y==u.y);

       }

       ///Testing inequality

       bool operator!=(xy u) const {

 	return  (x!=u.x) || (y!=u.y);

       }

     };

   ///Returns a vector multiplied by a scalar

   ///Returns a vector multiplied by a scalar

   ///\relates xy

   template<typename T> xy<T> operator*(const T &u,const xy<T> &x) {

     return x*u;

   }

   ///Read a plainvector from a stream

   ///Read a plainvector from a stream

   ///\relates xy

   ///

   template<typename T>

   inline

   std::istream& operator>>(std::istream &is, xy<T> &z)

   {

     is >> z.x >> z.y;

     return is;

   }

   ///Write a plainvector to a stream

   ///Write a plainvector to a stream

   ///\relates xy

   ///

   template<typename T>

   inline

   std::ostream& operator<<(std::ostream &os, xy<T> z)

   {

     os << "(" << z.x << ", " << z.y << ")";

     return os;

   }

   ///Rotate by 90 degrees

   ///Returns its parameter rotated by 90 degrees in positive direction.

   ///\relates xy

   ///

   template<typename T>

   inline xy<T> rot90(const xy<T> &z)

   {

     return xy<T>(-z.y,z.x);

   }

   ///Rotate by 270 degrees

   ///Returns its parameter rotated by 90 degrees in negative direction.

   ///\relates xy

   ///

   template<typename T>

   inline xy<T> rot270(const xy<T> &z)

   {

     return xy<T>(z.y,-z.x);

   }

   /// A class to calculate or store the bounding box of plainvectors.

   /// A class to calculate or store the bounding box of plainvectors.

   ///

   ///\author Attila Bernath

   template<typename T>

     class BoundingBox {

       xy<T> bottom_left, top_right;

       bool _empty;

     public:

       ///Default constructor: an empty bounding box

       BoundingBox() { _empty = true; }

       ///Constructing the instance from one point

       BoundingBox(xy<T> a) { bottom_left=top_right=a; _empty = false; }

       ///Is there any point added

       bool empty() const {

 	return _empty;

       }

       ///Makes the BoundingBox empty

       void clear() {

 	_empty=1;

       }

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

       xy<T> bottomLeft() const {

 	return bottom_left;

       }

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

       xy<T> topRight() const {

 	return top_right;

       }

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

       xy<T> bottomRight() const {

 	return xy<T>(top_right.x,bottom_left.y);

       }

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

       xy<T> topLeft() const {

 	return xy<T>(bottom_left.x,top_right.y);

       }

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

       T bottom() const {

 	return bottom_left.y;

       }

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

       T top() const {

 	return top_right.y;

       }

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

       T left() const {

 	return bottom_left.x;

       }

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

       T right() const {

 	return top_right.x;

       }

       ///Gives back the height of the box (if the bounding box is empty, then the return value is not defined) 

       T height() const {

 	return top_right.y-bottom_left.y;

       }

       ///Gives back the width of the box (if the bounding box is empty, then the return value is not defined) 

       T width() const {

 	return top_right.x-bottom_left.x;

       }

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

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

 	if (_empty)

 	  return false;

 	else{

 	  return ((u.x-bottom_left.x)*(top_right.x-u.x) >= 0 &&

 		  (u.y-bottom_left.y)*(top_right.y-u.y) >= 0 );

 	}

       }

       ///Increments a bounding box with a point

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

 	if (_empty){

 	  bottom_left=top_right=u;

 	  _empty = false;

 	}

 	else{

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

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

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

 	  if (top_right.y < u.y) top_right.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

   ///Map of x-coordinates of an xy<>-map

   ///\ingroup maps

   ///

   template<class M>

   class XMap 

   {

     M &_map;

   public:

     typedef typename M::Value::Value Value;

     typedef typename M::Key Key;

     ///\e

     XMap(M &map) : _map(map) {}

     Value operator[](Key k) const {return _map[k].x;}

     void set(Key k,Value v) {_map.set(k,typename M::Value(v,_map[k].y));}

   };

   ///Returns an \ref XMap class

   ///This function just returns an \ref XMap class.

   ///

   ///\ingroup maps

   ///\relates XMap

   template<class M> 

   inline XMap<M> xMap(M &m) 

   {

     return XMap<M>(m);

   }

   ///Constant (read only) version of \ref XMap

   ///\ingroup maps

   ///

   template<class M>

   class ConstXMap 

   {

     const M &_map;

   public:

     typedef typename M::Value::Value Value;

     typedef typename M::Key Key;

     ///\e

     ConstXMap(const M &map) : _map(map) {}

     Value operator[](Key k) const {return _map[k].x;}

   };

   ///Returns a \ref ConstXMap class

   ///This function just returns an \ref ConstXMap class.

   ///

   ///\ingroup maps

   ///\relates ConstXMap

   template<class M> 

   inline ConstXMap<M> xMap(const M &m) 

   {

     return ConstXMap<M>(m);

   }

   ///Map of y-coordinates of an xy<>-map

   ///\ingroup maps

   ///

   template<class M>

   class YMap 

   {

     M &_map;

   public:

     typedef typename M::Value::Value Value;

     typedef typename M::Key Key;

     ///\e

     YMap(M &map) : _map(map) {}

     Value operator[](Key k) const {return _map[k].y;}

     void set(Key k,Value v) {_map.set(k,typename M::Value(_map[k].x,v));}

   };

   ///Returns an \ref YMap class

   ///This function just returns an \ref YMap class.

   ///

   ///\ingroup maps

   ///\relates YMap

   template<class M> 

   inline YMap<M> yMap(M &m) 

   {

     return YMap<M>(m);

   }

   ///Constant (read only) version of \ref YMap

   ///\ingroup maps

   ///

   template<class M>

   class ConstYMap 

   {

     const M &_map;

   public:

     typedef typename M::Value::Value Value;

     typedef typename M::Key Key;

     ///\e

     ConstYMap(const M &map) : _map(map) {}

     Value operator[](Key k) const {return _map[k].y;}

   };

   ///Returns a \ref ConstYMap class

   ///This function just returns an \ref ConstYMap class.

   ///

   ///\ingroup maps

   ///\relates ConstYMap

   template<class M> 

   inline ConstYMap<M> yMap(const M &m) 

   {

     return ConstYMap<M>(m);

   }

   ///Map of the \ref xy::normSquare() "normSquare()" of an \ref xy "xy"-map

   ///Map of the \ref xy::normSquare() "normSquare()" of an \ref xy "xy"-map

   ///\ingroup maps

   ///

   template<class M>

   class NormSquareMap 

   {

     const M &_map;

   public:

     typedef typename M::Value::Value Value;

     typedef typename M::Key Key;

     ///\e

     NormSquareMap(const M &map) : _map(map) {}

     Value operator[](Key k) const {return _map[k].normSquare();}

   };

   ///Returns a \ref NormSquareMap class

   ///This function just returns an \ref NormSquareMap class.

   ///

   ///\ingroup maps

   ///\relates NormSquareMap

   template<class M> 

   inline NormSquareMap<M> normSquareMap(const M &m) 

   {

     return NormSquareMap<M>(m);

   }

   /// @}

 } //namespace lemon

 #endif //LEMON_XY_H