/***************************************************************************
 *                                                                         *
 *   This file is part of the Fotowall project,                            *
 *       http://www.enricoros.com/opensource/fotowall                      *
 *                                                                         *
 *   Copyright (C) 2009 by TANGUY Arnaud <arn.tanguy@gmail.com>            *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/

#include "CPixmap.h"
#include "Shared/GlowEffectWidget.h"
#include <QImage>
#include <cmath>

CPixmap::CPixmap() {
}

CPixmap::CPixmap(const QString &filePath) : QPixmap(filePath), m_filePath(filePath) {
}

CPixmap::CPixmap(const QImage &image) : QPixmap(QPixmap::fromImage(image)), m_image(image) {
}

CPixmap::CPixmap(const QPixmap &pixmap): QPixmap(pixmap){
}

void CPixmap::addEffect(const PictureEffect & effect) {
    switch (effect.effect) {
        case PictureEffect::ClearEffects:
            clearEffects();
            break;
        case PictureEffect::FlipH:
            toHFlip();
            break;
        case PictureEffect::FlipV:
            toVFlip();
            break;
        case PictureEffect::InvertColors:
            toInvertedColors();
            break;
        case PictureEffect::NVG:
            toNVG();
            break;
        case PictureEffect::BlackAndWhite:
            toBlackAndWhite();
            break;
        case PictureEffect::Glow:
            toGlow((int)effect.param);
            break;
        case PictureEffect::Sepia:
            toSepia();
            break;
        case PictureEffect::Opacity:
            m_effects.push_back(PictureEffect(PictureEffect::Opacity, (qreal)effect.param));
            break;
        case PictureEffect::Crop:
            toCropped(effect.rect);
            break;
        case PictureEffect::AutoBlend:
            toAutoBlend(effect.param);
            break;
    }
}

QList<PictureEffect> CPixmap::effects() const {
    return m_effects;
}

void CPixmap::clearEffects()
{
    if (!m_image.isNull())
        updateImage(m_image);
    else if (!m_filePath.isEmpty())
        load(m_filePath);
    m_effects.clear();
}

void CPixmap::toNVG() {
    m_effects.push_back(PictureEffect::NVG);
    QImage img = this->toImage();
    QImage dest(img.size(), QImage::Format_ARGB32);
    const int w = img.width();
    const int h = img.height();
    for (int y=0; y<h; y++) {
        for (int x=0; x<w; x++) {
            const QRgb pixel = img.pixel(x, y);
            unsigned int average = (qGreen(pixel) + qRed(pixel) + qBlue(pixel)) / 3;
            dest.setPixel(x, y, qRgba(average, average, average, qAlpha(pixel)));
        }
    }
    updateImage(dest);
}

void CPixmap::toInvertedColors()
{
    // can't use invertPixels, because it gives artifacts
    m_effects.push_back(PictureEffect::InvertColors);
    const QImage img = this->toImage();
    QImage inverted(img.size(), QImage::Format_ARGB32);
    const int w = img.width();
    const int h = img.height();
    for (int y=0; y<h; y++) {
        for (int x=0; x<w; x++) {
            QRgb pixel = img.pixel(x, y);
            pixel = qRgba(255 - qRed(pixel), 255 - qGreen(pixel), 255 - qBlue(pixel), qAlpha(pixel));
            inverted.setPixel(x,y,pixel);
        }
    }
    updateImage(inverted);
}

void CPixmap::toHFlip() {
    m_effects.push_back(PictureEffect::FlipH);
    QImage img = this->toImage().mirrored(true, false);
    updateImage(img);
}

void CPixmap::toVFlip() {
    m_effects.push_back(PictureEffect::FlipV);
    QImage img = this->toImage().mirrored(false, true);
    updateImage(img);
}

void CPixmap::toBlackAndWhite()
{
    m_effects.push_back(PictureEffect::BlackAndWhite);
    const QImage img = this->toImage();
    QImage dest(img.size(), QImage::Format_ARGB32);
    const int w = img.width();
    const int h = img.height();
    for (int y=0; y<h; y++) {
        for (int x=0; x<w; x++) {
            const QRgb pixel = img.pixel(x, y);
            unsigned int average = (qGreen(pixel)+ qRed(pixel) + qBlue(pixel)) / 3;
            if (average > 127)
                average = 255;
            else
                average = 0;
            dest.setPixel(x,y, qRgba(average, average, average, qAlpha(pixel)));
        }
    }
    updateImage(dest);
}

void CPixmap::toGlow(int radius) {
    m_effects.push_back(PictureEffect(PictureEffect::Glow, (qreal)radius));
    QImage dest = GlowEffectWidget::glown(this->toImage(), radius);
    updateImage(dest);
}

void CPixmap::toSepia()
{
    m_effects.push_back(PictureEffect::Sepia);
    const QImage img = this->toImage();
    QImage dest(img.size(), QImage::Format_ARGB32);
    const int w = img.width();
    const int h = img.height();
    for (int y=0; y<h; y++) {
        for (int x=0; x<w; x++) {
            QRgb pixel = img.pixel(x, y);
            const unsigned int average = (qGreen(pixel) + qRed(pixel) + qBlue(pixel)) / 3;
            const int red = average*1.176, green = average*0.837, blue = average*0.558;
            pixel = qRgba((red <= 255) ? red : 255, (green <= 255) ? green : 255, (blue <= 255) ? blue : 255, qAlpha(pixel));
            dest.setPixel(x,y,pixel);
        }
    }
    updateImage(dest);
}
/*
void CPixmap::toLuminosity(int value) {
    m_effects.push_back(...);
    QImage img = this->toImage();
    QImage dest(img.size(), img.format());
    QColor pixel;
    for(int x=0; x<img.width();x++) {
        for (int y=0; y<img.height(); y++) {
            pixel = img.pixel(x, y);
            int green = pixel.green() + value;
            int red = pixel.red() + value;
            int blue = pixel.blue() + value;
            if(green > 255) green = 255;
            else if(green < 0) green = 0;
            if(red > 255) red = 255;
            else if(red < 0) red = 0;
            if(blue > 255) blue = 255;
            else if(blue <0) blue = 0;

            pixel.setGreen(green);
            pixel.setBlue(blue);
            pixel.setRed(red);
            dest.setPixel(x,y,pixel.rgb());
        }
    }
    updateImage(dest);
}
*/
void CPixmap::toCropped(const QRect &cropRect)
{
    if (cropRect.isNull()) return;
    m_effects.push_back(PictureEffect(PictureEffect::Crop, PictureEffect::Crop, cropRect));
    const QImage img = this->toImage().copy(cropRect);
    updateImage(img);
}

void CPixmap::toAutoBlend(qreal strength)
{
    m_effects.push_back(PictureEffect(PictureEffect::AutoBlend, strength));
    const QImage img = this->toImage();
    QImage dest(img.size(), QImage::Format_ARGB32);
    const int w = img.width();
    const int h = img.height();
    // create a fast lookup-table for the 256 possible alpha levels {a = i^5^(2*strength - 1)}
    int gammaValue[256];
    qreal expIdx = pow((qreal)5, (strength * 2) - 1);
    for (int i = 0; i < 256; i++) {
        qreal unif = (qreal)i / 255.f;
        gammaValue[i] = (int)(255.f * pow(unif, expIdx));
    }
    for (int y=0; y<h; y++) {
        for (int x=0; x<w; x++) {
            QRgb pixel = img.pixel(x, y);
            const int gray = qGray(pixel);
            const int alpha = gammaValue[gray];
            pixel = qRgba(qRed(pixel), qGreen(pixel), qBlue(pixel), alpha);
            dest.setPixel(x, y, pixel);
        }
    }
    updateImage(dest);
}

void CPixmap::updateImage(const QImage & newImage)
{
    QImage copyImage = m_image;
    QString copyFilePath = m_filePath;
    QList<PictureEffect> copyEffects = m_effects;
    *this = fromImage(newImage);
    m_image = copyImage;
    m_filePath = copyFilePath;
    m_effects = copyEffects;
}