/**********************************************************************
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.osgeo.org
 *
 * Copyright (C) 2006 Refractions Research Inc.
 *
 * 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 <algorithm>
#include <cassert>
#include <cmath>

namespace geos {
namespace index { // geos::index
namespace strtree { // geos::index::strtree

/// A contiguous portion of 1D-space. Used internally by SIRtree.
//
/// @see SIRtree
///
class GEOS_DLL Interval {
public:
    Interval(double newMin, double newMax) : imin(newMin), imax(newMax) {
        assert(std::isnan(newMin) || std::isnan(newMax) || imin <= imax);
    }

    double getMin() const { return imin; }
    double getMax() const { return imax; }
    double getWidth() const { return imax - imin; }
    double getCentre() const { return (imin + imax) / 2; }
    Interval* expandToInclude(const Interval* other) {
        imax = std::max(imax, other->imax);
        imin = std::min(imin, other->imin);
        return this;
    }
    bool intersects(const Interval* other) const {
        return !(other->imin > imax || other->imax < imin);
    }
    bool equals(const Interval* other) const {
        return imin == other->imin && imax == other->imax;
    }
private:
    double imin;
    double imax;
};


} // namespace geos::index::strtree
} // namespace geos::index
} // namespace geos