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

 *

 * GEOS - Geometry Engine Open Source

 * http://geos.osgeo.org

 *

 * Copyright (C) 2021 Paul Ramsey <pramsey@cleverelephant.ca>

 * Copyright (C) 2021 Martin Davis

 *

 * This is free software; you can redistribute and/or modify it under

 * the terms of the GNU Lesser General Public Licence as published

 * by the Free Software Foundation.

 * See the COPYING file for more information.

 *

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

#pragma once

#include <geos/export.h>

#include <geos/geom/Coordinate.h>

#include <memory>

namespace geos {      // geos.

namespace operation { // geos.operation

namespace valid {     // geos.operation.valid

class GEOS_DLL PolygonRingSelfNode {

    using CoordinateXY = geos::geom::CoordinateXY;

private:

    CoordinateXY nodePt;

    const CoordinateXY* e00;

    const CoordinateXY* e01;

    const CoordinateXY* e10;

    const CoordinateXY* e11;

public:

    PolygonRingSelfNode(

        const CoordinateXY& p_nodePt,

        const CoordinateXY* p_e00,

        const CoordinateXY* p_e01,

        const CoordinateXY* p_e10,

        const CoordinateXY* p_e11)

        : nodePt(p_nodePt)

        , e00(p_e00)

        , e01(p_e01)

        , e10(p_e10)

        , e11(p_e11)

        {}

    /**

    * The node point.

    *

    * @return

    */

    const CoordinateXY* getCoordinate() const {

        return &nodePt;

    }

    /**

    * Tests if a self-touch has the segments of each half of the touch

    * lying in the exterior of a polygon.

    * This is a valid self-touch.

    * It applies to both shells and holes.

    * Only one of the four possible cases needs to be tested,

    * since the situation has full symmetry.

    *

    * @param isInteriorOnRight whether the interior is to the right of the parent ring

    * @return true if the self-touch is in the exterior

    */

    bool isExterior(bool isInteriorOnRight) const;

};

} // namespace geos.operation.valid

} // namespace geos.operation

} // namespace geos