/******************************************************************************

 *

 * Project:  Marching square algorithm

 * Purpose:  Core algorithm implementation for contour line generation.

 * Author:   Oslandia <infos at oslandia dot com>

 *

 ******************************************************************************

 * Copyright (c) 2018, Oslandia <infos at oslandia dot com>

 *

 * SPDX-License-Identifier: MIT

 ****************************************************************************/

#ifndef MARCHING_SQUARE_POINT_H

#define MARCHING_SQUARE_POINT_H

#include "utility.h"

#include <ostream>

#include <algorithm>

#include <cmath>

#include <list>

namespace marching_squares

{

// regular point

struct Point

{

    Point() : x(NaN), y(NaN)

    {

    }  // just to be able to make an uninitialized list

    Point(double x_, double y_) : x(x_), y(y_)

    {

    }

    double x;

    double y;

};

inline bool operator==(const Point &lhs, const Point &rhs)

{

    return (lhs.x == rhs.x) && (lhs.y == rhs.y);

}

inline std::ostream &operator<<(std::ostream &o, const Point &p)

{

    o << p.x << " " << p.y;

    return o;

}

// Test if a point is to the left or right of an infinite line.

// Returns true if it is to the left and right otherwise

// 0 if p2 is on the line and less than if p2 is to the right of the line

inline bool isLeft(const Point &p0, const Point &p1, const Point &p2)

{

    return ((p1.x - p0.x) * (p2.y - p0.y) - (p2.x - p0.x) * (p1.y - p0.y)) > 0;

}

// LineString type

typedef std::list<Point> LineString;

inline std::ostream &operator<<(std::ostream &o, const LineString &ls)

{

    o << "{";

    for (const auto &p : ls)

    {

        o << p << ", ";

    }

    o << "}";

    return o;

}

// Point with a value

struct ValuedPoint

{

    ValuedPoint(double x_, double y_, double value_)

        : x(x_), y(y_), value(value_)

    {

    }

    const double x;

    const double y;

    const double value;

};

}  // namespace marching_squares

#endif