#ifndef GEOMETRY_H
#define GEOMETRY_H

#include <iostream>
/****************************************************/
/*													*/
/*	This is a class for 2D vectors with standard	*/
/*	vector operations.								*/
/*													*/
/****************************************************/

using namespace std;

class Tuple
{
 public:

	// constructors
	Tuple() {data[0]=data[1];}					// default construcotr
	Tuple(const double x, const double y)	// constructor
		{data[0]=x, data[1]=y;}
	Tuple(const Tuple& toCopy);							// copy constructor

	// destructor
	virtual ~Tuple() {};

	// operators
	Tuple&		operator =	(const Tuple& toCopy);			// assignment
	const bool	operator ==	(const Tuple& toCompare) const;	// equality
	const bool	operator !=	(const Tuple& toCompare) const;	// inequality
	const Tuple	operator +	(const Tuple& toAdd) const;		// addition
	Tuple&		operator +=	(const Tuple& toAdd);			// unary addition
	const Tuple	operator -	() const;						// negation 
	const Tuple	operator -	(const Tuple& toSub) const;		// subtraction
	Tuple&		operator -=	(const Tuple& toSub);			// unary subtraction
	Tuple&		operator *=	(double scaleFactor);			// scalar unary multiplication
	Tuple&		operator /=	(double scaleFactor);			// sclar division
	

	// accessors
	double&		operator[]	(const int index);				// index
	const double&	operator[]	(const int index) const;	// read only indexing

	// vector operations
	const double dot(const Tuple& toDot) const;				// dot product
	Tuple& normalize(void);									// normalize
	Tuple getPerpendicular(void);
	const double length(void) const;							// compute length
  
 private:
	double data[2];

;
};

//  related functions
const Tuple	operator *(const Tuple& toMultiply, const double& scaleFactor);
const Tuple	operator *(const double& scaleFactor, const Tuple& toMultiply);
const Tuple operator /(const Tuple& toDivide, const double& scaleFactor);
ostream &operator<<(ostream &out_file, const Tuple& theTuple);

#endif // GEOMETRY_H