/**
 * \file
 *
 * \author Mattia Basaglia
 *
 * \copyright Copyright (C) 2013-2015 Mattia Basaglia
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */
#include <cmath>
#include "color_utils.hpp"

namespace color_widgets {
namespace detail {

QColor color_from_lch(qreal hue, qreal chroma, qreal luma, qreal alpha )
{
    qreal h1 = hue*6;
    qreal x = chroma*(1-qAbs(std::fmod(h1,2)-1));
    QColor col;
    if ( h1 >= 0 && h1 < 1 )
        col = QColor::fromRgbF(chroma,x,0);
    else if ( h1 < 2 )
        col = QColor::fromRgbF(x,chroma,0);
    else if ( h1 < 3 )
        col = QColor::fromRgbF(0,chroma,x);
    else if ( h1 < 4 )
        col = QColor::fromRgbF(0,x,chroma);
    else if ( h1 < 5 )
        col = QColor::fromRgbF(x,0,chroma);
    else if ( h1 < 6 )
        col = QColor::fromRgbF(chroma,0,x);

    qreal m = luma - color_lumaF(col);

    return QColor::fromRgbF(
        qBound(0.0,col.redF()+m,1.0),
        qBound(0.0,col.greenF()+m,1.0),
        qBound(0.0,col.blueF()+m,1.0),
        alpha);
}

QColor color_from_hsl(qreal hue, qreal sat, qreal lig, qreal alpha )
{
    qreal chroma = (1 - qAbs(2*lig-1))*sat;
    qreal h1 = hue*6;
    qreal x = chroma*(1-qAbs(std::fmod(h1,2)-1));
    QColor col;
    if ( h1 >= 0 && h1 < 1 )
        col = QColor::fromRgbF(chroma,x,0);
    else if ( h1 < 2 )
        col = QColor::fromRgbF(x,chroma,0);
    else if ( h1 < 3 )
        col = QColor::fromRgbF(0,chroma,x);
    else if ( h1 < 4 )
        col = QColor::fromRgbF(0,x,chroma);
    else if ( h1 < 5 )
        col = QColor::fromRgbF(x,0,chroma);
    else if ( h1 < 6 )
        col = QColor::fromRgbF(chroma,0,x);

    qreal m = lig-chroma/2;

    return QColor::fromRgbF(
        qBound(0.0,col.redF()+m,1.0),
        qBound(0.0,col.greenF()+m,1.0),
        qBound(0.0,col.blueF()+m,1.0),
        alpha);
}

} // namespace detail
} // namespace color_widgets
