//****************************************************************//
//                                                                //
// Copyright (c) 1997.                                            //
//      Dr. Michael A. Redmond                                    //
//                                                                //
// This software may not be distributed further without permission from     //
// Dr Michael A. Redmond.                                         //
//                                                                //
// This software is distributed WITHOUT ANY WARRANTY. No claims are made    //
// as to its functionality or purpose.                            //
//                                                                //
// Author: Dr Michael A. Redmond                            //
// Date: 2/11/97                                                  //
//                                                                //
//
//**************************************************************************//

// point.h: declaration of Point ADT
// conditional compilation to avoid trying to include same thing twice
#ifndef POINT_H
#define POINT_H

#include <iostream.h>
// io library typically used with c++ - has some improvements over stdio
//    (which still can be used, but usually isn't)
//    a major advantage of iostream is that its operators can be overloaded
//    so that user defined class objects can be displayed/read with the
//    same interface - see below

// Point ADT: class description
// Defines class and its interface to the world
//    implementation is in point.cpp
class Point {
        friend class Tw_Board;  // Tw_Board needs access to GetRow and GetCol
        friend class Tw_Link;  // Tw_Link needs access to GetRow and GetCol
        // public interface can be used by anybody
	public: // member functions
		// constructors
		Point();
		Point(int row, int col);
		// inspectors               
                Point Adjust(int horiz, int vert) const;
		// mutators -  establish new values of attributes (data members)
		// facilitators
                bool PointsEqual(const Point &right) const;

                // horizontal distance between two points
                int HorizDist(Point secpoint) const;
                // vertical distance between two points
                int VertDist(Point secpoint) const;
                // city block distance between two points
                int CityBlockDist(Point secpoint) const;
                // crow flight distance between two points
                float CrowDist(Point secpoint) const;

		// some stream facilitators
                // write to stream
		void Insert(ostream &sout) const;
                // read from stream
		void Extract(istream &sin);
 

        // protected interface can be used by objects that are in class,
        //    and objects that are in a subtype class (derived class)
	protected:
		// inspectors
                //    return values of attributes (data members)
		int GetRow() const;
		int GetCol() const;
		// mutators
                //    establish new values of attributes (data members)
		void SetRow(int row);
		void SetCol(int col);
        // private members can only be used by other member functions and
        //    operators of this class
        //    typically all attributes (data members) go here
	private:
		// data members
		int RowNo;
		int ColNo;
};

// below overloads standard c++ operators so that they can be used 
// with point class objects, so syntax is like with ints floats etc
//
// Point ADT: auxiliary operator description

ostream& operator<<(ostream &sout, const Point &s);
istream& operator>>(istream &sin, Point &r);
bool operator==(const Point &left, const Point &right);

#endif