/* This file is part of the KDE project
 * SPDX-FileCopyrightText: 2010 Carlos Licea <carlos@kdab.com>
 *
 * SPDX-License-Identifier: LGPL-2.0-or-later
 */

#include "MonoFilterEffect.h"
#include <KoFilterEffectRenderContext.h>

#include <QImage>

MonoFilterEffect::MonoFilterEffect()
: KoFilterEffect(MonoFilterEffectId, "Mono Effect")
{
}

MonoFilterEffect::~MonoFilterEffect()
{
}

void MonoFilterEffect::save(KoXmlWriter& /*writer*/)
{
}

bool MonoFilterEffect::load(const KoXmlElement& /*element*/, const KoFilterEffectLoadingContext& /*context*/)
{
    return true;
}

QImage MonoFilterEffect::processImage(const QImage& image, const KoFilterEffectRenderContext& context) const
{
    QImage result = image.convertToFormat(QImage::Format_ARGB32);
    QRgb* pixel = reinterpret_cast<QRgb*>( result.bits() );
    const int right = context.filterRegion().right();
    const int bottom = context.filterRegion().bottom();
    const int width = result.width();
    for( int row = context.filterRegion().top(); row < bottom; ++row ) {
        for( int col = context.filterRegion().left(); col < right; ++col ){
            const QRgb currentPixel = pixel[row * width + col];
            const int red = qRed(currentPixel);
            const int green = qGreen(currentPixel);
            const int blue = qBlue(currentPixel);
            const int alpha = qAlpha(currentPixel);
            const int monoValue = ( (red * 11 + green * 16 + blue * 5) / 32 ) / 127 * 255;
            pixel[row * width + col] = qRgba(monoValue, monoValue, monoValue, alpha);
        }
    }
    return result;
}

