/*
 * © Copyright 2014 – Urheberrechtshinweis
 * Alle Rechte vorbehalten / All Rights Reserved
 *
 * Programmcode ist urheberrechtlich geschuetzt.
 * Das Urheberrecht liegt, soweit nicht ausdruecklich anders gekennzeichnet, bei Frank Ebner.
 * Keine Verwendung ohne explizite Genehmigung.
 * (vgl. § 106 ff UrhG / § 97 UrhG)
 */

#ifndef POINT2_H
#define POINT2_H

#include <cmath>
#include <algorithm>
#include <string>

/**
 * 2D Point
 */
struct Point2 {

	float x;
	float y;

	/** ctor */
	Point2() : x(0), y(0) {;}

	/** ctor */
	Point2(const float x, const float y) : x(x), y(y) {;}

	Point2 operator - () const {return Point2(-x, -y);}


	Point2 operator + (const Point2& o) const {return Point2(x+o.x, y+o.y);}

	Point2 operator - (const Point2& o) const {return Point2(x-o.x, y-o.y);}

	Point2 operator * (const float v) const {return Point2(v*x, v*y);}

	Point2 operator / (const float v) const {return Point2(x/v, y/v);}


	Point2& operator *= (const float v) {x*=v; y*=v; return *this;}

	Point2& operator /= (const float v) {x/=v; y/=v; return *this;}

	Point2& operator += (const Point2& o) {x+=o.x; y+=o.y; return *this;}

	Point2& operator -= (const Point2& o) {x-=o.x; y-=o.y; return *this;}


	bool operator == (const Point2& o) const {return x==o.x && y==o.y;}

	bool operator != (const Point2& o) const {return x!=o.x || y!=o.y;}

	bool eq (const Point2& o, const float delta) const { return eq(x,o.x,delta) && eq(y,o.y,delta); }

	Point2 perpendicular() const {return Point2(-y, x);}

	float length() const {return std::sqrt(x*x + y*y);}

	Point2 normalized() const {return (*this) / length();}

	Point2 rotated(const float rad) const {
		return Point2(x*std::cos(rad)-y*std::sin(rad), x*std::sin(rad)+y*std::cos(rad));
	}

	/** get the distance between this point and the other one */
	float getDistance(const Point2& o) const {
		const float dx = x - o.x;
		const float dy = y - o.y;
		return std::sqrt(dx*dx + dy*dy);
	}

	std::string asString() const {
		return "(" + std::to_string(x) + "," + std::to_string(y) + ")";
	}

private:

	static inline bool eq(const float a, const float b, const float delta) {return std::abs(a-b) <= delta;}
	static inline bool ne(const float a, const float b, const float delta) {return std::abs(a-b)  > delta;}

};

inline float dot(const Point2 p1, const Point2 p2) {
	return (p1.x*p2.x) + (p1.y*p2.y);
}

inline float determinant(const Point2 p1, const Point2 p2) {
	return (p1.x*p2.y) - (p1.y*p2.x);
}

inline void swap(Point2& p1, Point2& p2) {
	std::swap(p1.x, p2.x);
	std::swap(p1.y, p2.y);
}

namespace std {

    template <> struct hash<Point2> {
	    std::size_t operator()(const Point2& p) const {
			uint32_t x = *((uint32_t*)&(p.x));
			uint32_t y = *((uint32_t*)&(p.y));
			return std::hash<uint32_t>()(x^y);
		}
    };

}

#endif // POINT2_H