/* ============================================================
 *
 * This file is a part of digiKam project
 * http://www.digikam.org
 *
 * Date        : 2004-12-01
 * Description : image histogram adjust curves.
 *
 * Copyright (C) 2004-2008 by Gilles Caulier <caulier dot gilles at gmail dot 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, 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 General Public License for more details.
 *
 * ============================================================ */

// C++ includes.

#include <cmath>

// TQt includes.

#include <tqlayout.h>
#include <tqcolor.h>
#include <tqgroupbox.h>
#include <tqhgroupbox.h>
#include <tqvgroupbox.h>
#include <tqlabel.h>
#include <tqpainter.h>
#include <tqcombobox.h>
#include <tqspinbox.h>
#include <tqwhatsthis.h>
#include <tqtooltip.h>
#include <tqpushbutton.h>
#include <tqlayout.h>
#include <tqframe.h>
#include <tqtimer.h>
#include <tqhbuttongroup.h> 
#include <tqpixmap.h>

// KDE includes.

#include <tdeconfig.h>
#include <kcursor.h>
#include <klocale.h>
#include <knuminput.h>
#include <kmessagebox.h>
#include <kselect.h>
#include <tdefiledialog.h>
#include <kglobalsettings.h>
#include <kaboutdata.h>
#include <khelpmenu.h>
#include <kiconloader.h>
#include <kapplication.h>
#include <kpopupmenu.h>
#include <kstandarddirs.h>

// Local includes.

#include "version.h"
#include "ddebug.h"
#include "imageiface.h"
#include "imagewidget.h"
#include "imagehistogram.h"
#include "imagecurves.h"
#include "histogramwidget.h"
#include "curveswidget.h"
#include "colorgradientwidget.h"
#include "dimgimagefilters.h"
#include "adjustcurves.h"
#include "adjustcurves.moc"

namespace DigikamAdjustCurvesImagesPlugin
{

AdjustCurveDialog::AdjustCurveDialog(TQWidget* parent)
                 : Digikam::ImageDlgBase(parent, i18n("Adjust Color Curves"), "adjustcurves", true, false)
{
    m_destinationPreviewData = 0L;

    Digikam::ImageIface iface(0, 0);
    uchar *data     = iface.getOriginalImage();
    int w           = iface.originalWidth();
    int h           = iface.originalHeight();
    bool sixteenBit = iface.originalSixteenBit();
    bool hasAlpha   = iface.originalHasAlpha();
    m_originalImage = Digikam::DImg(w, h, sixteenBit, hasAlpha ,data);
    delete [] data;

    m_histoSegments = m_originalImage.sixteenBit() ? 65535 : 255;
    m_curves = new Digikam::ImageCurves(m_originalImage.sixteenBit());

    // About data and help button.

    TDEAboutData* about = new TDEAboutData("digikam",
                                       I18N_NOOP("Adjust Color Curves"),
                                       digikam_version,
                                       I18N_NOOP("An image-histogram-curves adjustment plugin for digiKam."),
                                       TDEAboutData::License_GPL,
                                       "(c) 2004-2008, Gilles Caulier",
                                       0,
                                       "http://www.digikam.org");

    about->addAuthor("Gilles Caulier", I18N_NOOP("Author and maintainer"),
                     "caulier dot gilles at gmail dot com");

    setAboutData(about);
    
    // -------------------------------------------------------------

    m_previewWidget = new Digikam::ImageWidget("adjustcurves Tool Dialog", plainPage(),
                                               i18n("<p>This is the image's curve-adjustments preview. "
                                                    "You can pick a spot on the image "
                                                    "to see the corresponding level in the histogram."));
    setPreviewAreaWidget(m_previewWidget); 

    // -------------------------------------------------------------

    TQWidget *gboxSettings = new TQWidget(plainPage());
    TQGridLayout* grid     = new TQGridLayout( gboxSettings, 5, 5, spacingHint());

    TQLabel *label1 = new TQLabel(i18n("Channel:"), gboxSettings);
    label1->setAlignment ( TQt::AlignRight | TQt::AlignVCenter );
    m_channelCB = new TQComboBox( false, gboxSettings );
    m_channelCB->insertItem( i18n("Luminosity") );
    m_channelCB->insertItem( i18n("Red") );
    m_channelCB->insertItem( i18n("Green") );
    m_channelCB->insertItem( i18n("Blue") );
    m_channelCB->insertItem( i18n("Alpha") );
    m_channelCB->setCurrentText( i18n("Luminosity") );
    TQWhatsThis::add( m_channelCB, i18n("<p>Select the histogram channel to display here:<p>"
                                       "<b>Luminosity</b>: display the image's luminosity values.<p>"
                                       "<b>Red</b>: display the red image-channel values.<p>"
                                       "<b>Green</b>: display the green image-channel values.<p>"
                                       "<b>Blue</b>: display the blue image-channel values.<p>"
                                       "<b>Alpha</b>: display the alpha image-channel values. "
                                       "This channel corresponds to the transparency value and "
                                       "is supported by some image formats, such as PNG or TIF."));

    m_scaleBG = new TQHButtonGroup(gboxSettings);
    TQWhatsThis::add( m_scaleBG, i18n("<p>Select the histogram scale here.<p>"
                                     "If the image's maximal counts are small, you can use the linear scale.<p>"
                                     "Logarithmic scale can be used when the maximal counts are big; "
                                     "if it is used, all values (small and large) will be visible on the graph."));
    
    TQPushButton *linHistoButton = new TQPushButton( m_scaleBG );
    TQToolTip::add( linHistoButton, i18n( "<p>Linear" ) );
    m_scaleBG->insert(linHistoButton, Digikam::CurvesWidget::LinScaleHistogram);
    TDEGlobal::dirs()->addResourceType("histogram-lin", TDEGlobal::dirs()->kde_default("data") + "digikam/data");
    TQString directory = TDEGlobal::dirs()->findResourceDir("histogram-lin", "histogram-lin.png");
    linHistoButton->setPixmap( TQPixmap( directory + "histogram-lin.png" ) );
    linHistoButton->setToggleButton(true);
    
    TQPushButton *logHistoButton = new TQPushButton( m_scaleBG );
    TQToolTip::add( logHistoButton, i18n( "<p>Logarithmic" ) );
    m_scaleBG->insert(logHistoButton, Digikam::CurvesWidget::LogScaleHistogram);
    TDEGlobal::dirs()->addResourceType("histogram-log", TDEGlobal::dirs()->kde_default("data") + "digikam/data");
    directory = TDEGlobal::dirs()->findResourceDir("histogram-log", "histogram-log.png");
    logHistoButton->setPixmap( TQPixmap( directory + "histogram-log.png" ) );
    logHistoButton->setToggleButton(true);
    
    m_scaleBG->setExclusive(true);
    m_scaleBG->setButton(Digikam::CurvesWidget::LogScaleHistogram);
    m_scaleBG->setFrameShape(TQFrame::NoFrame);
    m_scaleBG->setInsideMargin( 0 );

    TQHBoxLayout* l1 = new TQHBoxLayout();
    l1->addStretch(10);
    l1->addWidget(m_scaleBG);
    
    grid->addMultiCellWidget(label1, 0, 0, 1, 1);
    grid->addMultiCellWidget(m_channelCB, 0, 0, 2, 2);
    grid->addMultiCellLayout(l1, 0, 0, 4, 5);
    
    // -------------------------------------------------------------

    TQWidget *curveBox = new TQWidget(gboxSettings);
    TQGridLayout* gl   = new TQGridLayout(curveBox, 4, 2, 0);

    m_histogramWidget = new Digikam::HistogramWidget(256, 140, curveBox, false, true, true);
    TQWhatsThis::add( m_histogramWidget, i18n("<p>Here you can see the target preview image histogram drawing "
                                             "of the selected image channel. This one is re-computed at any "
                                             "curves settings changes."));
    
    m_vGradient = new Digikam::ColorGradientWidget( Digikam::ColorGradientWidget::Vertical, 10, curveBox );
    m_vGradient->setColors( TQColor( "white" ), TQColor( "black" ) );

    TQLabel *spacev = new TQLabel(curveBox);
    spacev->setFixedWidth(1);

    m_curvesWidget = new Digikam::CurvesWidget(256, 256, m_originalImage.bits(), m_originalImage.width(),
                                               m_originalImage.height(), m_originalImage.sixteenBit(),
                                               m_curves, curveBox);
    TQWhatsThis::add( m_curvesWidget, i18n("<p>This is the curve drawing of the selected channel from "
                                          "original image"));
    
    TQLabel *spaceh = new TQLabel(curveBox);
    spaceh->setFixedHeight(1);

    m_hGradient = new Digikam::ColorGradientWidget( Digikam::ColorGradientWidget::Horizontal, 10, curveBox );
    m_hGradient->setColors( TQColor( "black" ), TQColor( "white" ) );

    gl->addMultiCellWidget(m_histogramWidget, 0, 0, 2, 2);
    gl->addMultiCellWidget(m_vGradient, 2, 2, 0, 0);
    gl->addMultiCellWidget(spacev, 2, 2, 1, 1);
    gl->addMultiCellWidget(m_curvesWidget, 2, 2, 2, 2);
    gl->addMultiCellWidget(spaceh, 3, 3, 2, 2);
    gl->addMultiCellWidget(m_hGradient, 4, 4, 2, 2);
    gl->setRowSpacing(1, spacingHint());

    grid->addMultiCellWidget(curveBox, 2, 3, 0, 5);
    
    // -------------------------------------------------------------
    
    m_curveType = new TQHButtonGroup(gboxSettings);
    m_curveFree = new TQPushButton(m_curveType);
    m_curveType->insert(m_curveFree, FreeDrawing);
    TDEGlobal::dirs()->addResourceType("curvefree", TDEGlobal::dirs()->kde_default("data") +
                                     "digikam/data");
    directory = TDEGlobal::dirs()->findResourceDir("curvefree", "curvefree.png");
    m_curveFree->setPixmap( TQPixmap( directory + "curvefree.png" ) );
    m_curveFree->setToggleButton(true);
    TQToolTip::add( m_curveFree, i18n( "Curve free mode" ) );
    TQWhatsThis::add( m_curveFree, i18n("<p>With this button, you can draw your curve free-hand with the mouse."));
    m_curveSmooth = new TQPushButton(m_curveType);
    m_curveType->insert(m_curveSmooth, SmoothDrawing);
    TDEGlobal::dirs()->addResourceType("curvemooth", TDEGlobal::dirs()->kde_default("data") +
                                     "digikam/data");
    directory = TDEGlobal::dirs()->findResourceDir("curvemooth", "curvemooth.png");
    m_curveSmooth->setPixmap( TQPixmap( directory + "curvemooth.png" ) );
    m_curveSmooth->setToggleButton(true);
    TQToolTip::add( m_curveSmooth, i18n( "Curve smooth mode" ) );
    TQWhatsThis::add( m_curveSmooth, i18n("<p>With this button, you constrains the curve type to a smooth line with tension."));
    m_curveType->setExclusive(true);
    m_curveType->setButton(SmoothDrawing);
    m_curveType->setFrameShape(TQFrame::NoFrame);
    
    // -------------------------------------------------------------
    
    m_pickerColorButtonGroup = new TQHButtonGroup(gboxSettings);
    m_pickBlack = new TQPushButton(m_pickerColorButtonGroup);
    m_pickerColorButtonGroup->insert(m_pickBlack, BlackTonal);
    TDEGlobal::dirs()->addResourceType("color-picker-black", TDEGlobal::dirs()->kde_default("data") +
                                     "digikam/data");
    directory = TDEGlobal::dirs()->findResourceDir("color-picker-black", "color-picker-black.png");
    m_pickBlack->setPixmap( TQPixmap( directory + "color-picker-black.png" ) );
    m_pickBlack->setToggleButton(true);
    TQToolTip::add( m_pickBlack, i18n( "All channels shadow tone color picker" ) );
    TQWhatsThis::add( m_pickBlack, i18n("<p>With this button, you can pick the color from original image used to set <b>Shadow Tone</b> "
                                       "smooth curves point on Red, Green, Blue, and Luminosity channels."));
    m_pickGray  = new TQPushButton(m_pickerColorButtonGroup);
    m_pickerColorButtonGroup->insert(m_pickGray, GrayTonal);
    TDEGlobal::dirs()->addResourceType("color-picker-grey", TDEGlobal::dirs()->kde_default("data") +
                                     "digikam/data");
    directory = TDEGlobal::dirs()->findResourceDir("color-picker-grey", "color-picker-grey.png");
    m_pickGray->setPixmap( TQPixmap( directory + "color-picker-grey.png" ) );
    m_pickGray->setToggleButton(true);
    TQToolTip::add( m_pickGray, i18n( "All channels middle tone color picker" ) );
    TQWhatsThis::add( m_pickGray, i18n("<p>With this button, you can pick the color from original image used to set <b>Middle Tone</b> "
                                      "smooth curves point on Red, Green, Blue, and Luminosity channels."));
    m_pickWhite = new TQPushButton(m_pickerColorButtonGroup);
    m_pickerColorButtonGroup->insert(m_pickWhite, WhiteTonal);
    TDEGlobal::dirs()->addResourceType("color-picker-white", TDEGlobal::dirs()->kde_default("data") +
                                     "digikam/data");
    directory = TDEGlobal::dirs()->findResourceDir("color-picker-white", "color-picker-white.png");
    m_pickWhite->setPixmap( TQPixmap( directory + "color-picker-white.png" ) );
    m_pickWhite->setToggleButton(true);
    TQToolTip::add( m_pickWhite, i18n( "All channels highlight tone color picker" ) );
    TQWhatsThis::add( m_pickWhite, i18n("<p>With this button, you can pick the color from original image used to set <b>Highlight Tone</b> "
                                       "smooth curves point on Red, Green, Blue, and Luminosity channels."));
    m_pickerColorButtonGroup->setExclusive(true);
    m_pickerColorButtonGroup->setFrameShape(TQFrame::NoFrame);
    
    // -------------------------------------------------------------

    m_resetButton = new TQPushButton(i18n("&Reset"), gboxSettings);
    m_resetButton->setPixmap( SmallIcon("reload_page", 18) );
    TQToolTip::add( m_resetButton, i18n( "Reset current channel curves' values." ) );
    TQWhatsThis::add( m_resetButton, i18n("<p>If you press this button, all curves' values "
                                         "from the current selected channel "
                                         "will be reset to the default values."));

    TQHBoxLayout* l3 = new TQHBoxLayout();
    l3->addWidget(m_curveType);
    l3->addWidget(m_pickerColorButtonGroup);
    l3->addWidget(m_resetButton);
    l3->addStretch(10);
    
    grid->addMultiCellLayout(l3, 4, 4, 1, 5);
    
    // -------------------------------------------------------------
            

    grid->setRowStretch(5, 10);
    setUserAreaWidget(gboxSettings);

    // -------------------------------------------------------------
    
    connect(m_curvesWidget, TQT_SIGNAL(signalCurvesChanged()),
            this, TQT_SLOT(slotTimer()));
    
    connect(m_previewWidget, TQT_SIGNAL(spotPositionChangedFromOriginal( const Digikam::DColor &, const TQPoint & )),
            this, TQT_SLOT(slotSpotColorChanged( const Digikam::DColor & )));

    connect(m_previewWidget, TQT_SIGNAL(spotPositionChangedFromTarget( const Digikam::DColor &, const TQPoint & )),
            this, TQT_SLOT(slotColorSelectedFromTarget( const Digikam::DColor & )));
            
    connect(m_previewWidget, TQT_SIGNAL(signalResized()),
            this, TQT_SLOT(slotEffect()));                                                            
            
    // -------------------------------------------------------------
    // ComboBox slots.

    connect(m_channelCB, TQT_SIGNAL(activated(int)),
            this, TQT_SLOT(slotChannelChanged(int)));

    connect(m_scaleBG, TQT_SIGNAL(released(int)),
            this, TQT_SLOT(slotScaleChanged(int)));
            
    connect(m_curveType, TQT_SIGNAL(clicked(int)),
            this, TQT_SLOT(slotCurveTypeChanged(int)));
    
    // -------------------------------------------------------------
    // Bouttons slots.

    connect(m_resetButton, TQT_SIGNAL(clicked()),
            this, TQT_SLOT(slotResetCurrentChannel()));

    connect(m_pickerColorButtonGroup, TQT_SIGNAL(released(int)),
            this, TQT_SLOT(slotPickerColorButtonActived()));
}

AdjustCurveDialog::~AdjustCurveDialog()
{
    m_histogramWidget->stopHistogramComputation();

    if (m_destinationPreviewData) 
       delete [] m_destinationPreviewData;
       
    delete m_histogramWidget;
    delete m_curvesWidget;
    delete m_previewWidget;
    delete m_curves;
}

void AdjustCurveDialog::slotPickerColorButtonActived()
{
    // Save previous rendering mode and toggle to original image.
    m_currentPreviewMode = m_previewWidget->getRenderingPreviewMode();
    m_previewWidget->setRenderingPreviewMode(Digikam::ImageGuideWidget::PreviewOriginalImage);
}

void AdjustCurveDialog::slotSpotColorChanged(const Digikam::DColor &color)
{
    Digikam::DColor sc = color;

    if ( m_pickBlack->isOn() )
    {
       // Black tonal curves point.
       m_curves->setCurvePoint(Digikam::ImageHistogram::ValueChannel, 1, 
                               TQPoint(TQMAX(TQMAX(sc.red(), sc.green()), sc.blue()), 42*m_histoSegments/256));
       m_curves->setCurvePoint(Digikam::ImageHistogram::RedChannel, 1, TQPoint(sc.red(), 42*m_histoSegments/256));
       m_curves->setCurvePoint(Digikam::ImageHistogram::GreenChannel, 1, TQPoint(sc.green(), 42*m_histoSegments/256));
       m_curves->setCurvePoint(Digikam::ImageHistogram::BlueChannel, 1, TQPoint(sc.blue(), 42*m_histoSegments/256));
       m_pickBlack->setOn(false);
    }
    else if ( m_pickGray->isOn() )
    {
       // Gray tonal curves point.
       m_curves->setCurvePoint(Digikam::ImageHistogram::ValueChannel, 8, 
                               TQPoint(TQMAX(TQMAX(sc.red(), sc.green()), sc.blue()), 128*m_histoSegments/256));
       m_curves->setCurvePoint(Digikam::ImageHistogram::RedChannel, 8, TQPoint(sc.red(), 128*m_histoSegments/256));
       m_curves->setCurvePoint(Digikam::ImageHistogram::GreenChannel, 8, TQPoint(sc.green(), 128*m_histoSegments/256));
       m_curves->setCurvePoint(Digikam::ImageHistogram::BlueChannel, 8, TQPoint(sc.blue(), 128*m_histoSegments/256));
       m_pickGray->setOn(false);
    }
    else if ( m_pickWhite->isOn() )
    {
       // White tonal curves point.
       m_curves->setCurvePoint(Digikam::ImageHistogram::ValueChannel, 15,
                               TQPoint(TQMAX(TQMAX(sc.red(), sc.green()), sc.blue()), 213*m_histoSegments/256));
       m_curves->setCurvePoint(Digikam::ImageHistogram::RedChannel, 15, TQPoint(sc.red(), 213*m_histoSegments/256));
       m_curves->setCurvePoint(Digikam::ImageHistogram::GreenChannel, 15, TQPoint(sc.green(), 213*m_histoSegments/256));
       m_curves->setCurvePoint(Digikam::ImageHistogram::BlueChannel, 15, TQPoint(sc.blue(), 213*m_histoSegments/256));
       m_pickWhite->setOn(false);
    }
    else
    {
       m_curvesWidget->setCurveGuide(color);
       return;
    }

    // Calculate Red, green, blue curves.
    
    for (int i = Digikam::ImageHistogram::ValueChannel ; i <= Digikam::ImageHistogram::BlueChannel ; i++)
       m_curves->curvesCalculateCurve(i);
    
    m_curvesWidget->repaint(false);
    
    // restore previous rendering mode.
    m_previewWidget->setRenderingPreviewMode(m_currentPreviewMode);
       
    slotEffect();  
}

void AdjustCurveDialog::slotColorSelectedFromTarget( const Digikam::DColor &color )
{
    m_histogramWidget->setHistogramGuideByColor(color);
}

void AdjustCurveDialog::slotResetCurrentChannel()
{
    m_curves->curvesChannelReset(m_channelCB->currentItem());

    m_curvesWidget->reset();
    slotEffect();
    m_histogramWidget->reset();
}

void AdjustCurveDialog::slotEffect()
{
    Digikam::ImageIface* iface = m_previewWidget->imageIface();
    uchar *orgData             = iface->getPreviewImage();
    int w                      = iface->previewWidth();
    int h                      = iface->previewHeight();
    bool sb                    = iface->previewSixteenBit();

    // Create the new empty destination image data space.
    m_histogramWidget->stopHistogramComputation();

    if (m_destinationPreviewData) 
       delete [] m_destinationPreviewData;
    
    m_destinationPreviewData = new uchar[w*h*(sb ? 8 : 4)];

    // Calculate the LUT to apply on the image.
    m_curves->curvesLutSetup(Digikam::ImageHistogram::AlphaChannel);

    // Apply the lut to the image.
    m_curves->curvesLutProcess(orgData, m_destinationPreviewData, w, h);

    iface->putPreviewImage(m_destinationPreviewData);
    m_previewWidget->updatePreview();

    // Update histogram.
    m_histogramWidget->updateData(m_destinationPreviewData, w, h, sb, 0, 0, 0, false);
    delete [] orgData;
}

void AdjustCurveDialog::finalRendering()
{
    kapp->setOverrideCursor( KCursor::waitCursor() );
    Digikam::ImageIface* iface = m_previewWidget->imageIface();
    uchar *orgData             = iface->getOriginalImage();
    int w                      = iface->originalWidth();
    int h                      = iface->originalHeight();
    bool sb                    = iface->originalSixteenBit();
    
    // Create the new empty destination image data space.
    uchar* desData = new uchar[w*h*(sb ? 8 : 4)];

    // Calculate the LUT to apply on the image.
    m_curves->curvesLutSetup(Digikam::ImageHistogram::AlphaChannel);

    // Apply the lut to the image.
    m_curves->curvesLutProcess(orgData, desData, w, h);

    iface->putOriginalImage(i18n("Adjust Curve"), desData);
    kapp->restoreOverrideCursor();

    delete [] orgData;
    delete [] desData;
    accept();
}

void AdjustCurveDialog::slotChannelChanged(int channel)
{
    switch(channel)
    {
       case LuminosityChannel:
          m_histogramWidget->m_channelType = Digikam::HistogramWidget::ValueHistogram;
          m_hGradient->setColors( TQColor( "black" ), TQColor( "white" ) );
          m_curvesWidget->m_channelType = Digikam::CurvesWidget::ValueHistogram;
          m_vGradient->setColors( TQColor( "white" ), TQColor( "black" ) );
          break;
       
        case RedChannel:
          m_histogramWidget->m_channelType = Digikam::HistogramWidget::RedChannelHistogram;
          m_hGradient->setColors( TQColor( "black" ), TQColor( "red" ) );
          m_curvesWidget->m_channelType = Digikam::CurvesWidget::RedChannelHistogram;
          m_vGradient->setColors( TQColor( "red" ), TQColor( "black" ) );
          break;

       case GreenChannel:
          m_histogramWidget->m_channelType = Digikam::HistogramWidget::GreenChannelHistogram;
          m_hGradient->setColors( TQColor( "black" ), TQColor( "green" ) );
          m_curvesWidget->m_channelType = Digikam::CurvesWidget::GreenChannelHistogram;
          m_vGradient->setColors( TQColor( "green" ), TQColor( "black" ) );
          break;

       case BlueChannel:
          m_histogramWidget->m_channelType = Digikam::HistogramWidget::BlueChannelHistogram;
          m_hGradient->setColors( TQColor( "black" ), TQColor( "blue" ) );
          m_curvesWidget->m_channelType = Digikam::CurvesWidget::BlueChannelHistogram;
          m_vGradient->setColors( TQColor( "blue" ), TQColor( "black" ) );
          break;

       case AlphaChannel:
          m_histogramWidget->m_channelType = Digikam::HistogramWidget::AlphaChannelHistogram;
          m_hGradient->setColors( TQColor( "black" ), TQColor( "white" ) );
          m_curvesWidget->m_channelType = Digikam::CurvesWidget::AlphaChannelHistogram;
          m_vGradient->setColors( TQColor( "white" ), TQColor( "black" ) );
          break;
    }

    m_curveType->setButton(m_curves->getCurveType(channel));
                
    m_curvesWidget->repaint(false);
    m_histogramWidget->repaint(false);
}

void AdjustCurveDialog::slotScaleChanged(int scale)
{
    m_curvesWidget->m_scaleType = scale;
    m_histogramWidget->m_scaleType = scale;
    m_histogramWidget->repaint(false);
    m_curvesWidget->repaint(false);
}

void AdjustCurveDialog::slotCurveTypeChanged(int type)
{
    switch(type)
    {
       case SmoothDrawing:          
       {
          m_curves->setCurveType(m_curvesWidget->m_channelType, Digikam::ImageCurves::CURVE_SMOOTH);
          m_pickerColorButtonGroup->setEnabled(true);
          break;
       }
       
       case FreeDrawing:          
       {
          m_curves->setCurveType(m_curvesWidget->m_channelType, Digikam::ImageCurves::CURVE_FREE);
          m_pickerColorButtonGroup->setEnabled(false);
          break;
       }
    }
    
    m_curvesWidget->curveTypeChanged();
}

void AdjustCurveDialog::readUserSettings()
{
    TDEConfig* config = kapp->config();
    config->setGroup("adjustcurves Tool Dialog");

    m_channelCB->setCurrentItem(config->readNumEntry("Histogram Channel", 0));    // Luminosity.
    m_scaleBG->setButton(config->readNumEntry("Histogram Scale", Digikam::HistogramWidget::LogScaleHistogram));

    m_curvesWidget->reset();

    for (int i = 0 ; i < 5 ; i++)
    {
        m_curves->curvesChannelReset(i);
        m_curves->setCurveType(i, (Digikam::ImageCurves::CurveType)config->readNumEntry(TQString("CurveTypeChannel%1").arg(i),
                                                                                        Digikam::ImageCurves::CURVE_SMOOTH));

        for (int j = 0 ; j < 17 ; j++)
        {
            TQPoint disable(-1, -1);
            TQPoint p = config->readPointEntry(TQString("CurveAjustmentChannel%1Point%2").arg(i).arg(j), &disable);
    
            if (m_originalImage.sixteenBit() && p.x() != -1)
            {
                p.setX(p.x()*255);
                p.setY(p.y()*255);
            }
    
            m_curves->setCurvePoint(i, j, p);
        }
 
        m_curves->curvesCalculateCurve(i);
    }

    slotChannelChanged(m_channelCB->currentItem());
    slotScaleChanged(m_scaleBG->selectedId());
}

void AdjustCurveDialog::writeUserSettings()
{
    TDEConfig* config = kapp->config();
    config->setGroup("adjustcurves Tool Dialog");
    config->writeEntry("Histogram Channel", m_channelCB->currentItem());
    config->writeEntry("Histogram Scale", m_scaleBG->selectedId());

    for (int i = 0 ; i < 5 ; i++)
    {
        config->writeEntry(TQString("CurveTypeChannel%1").arg(i), m_curves->getCurveType(i));
        
        for (int j = 0 ; j < 17 ; j++)
        {
            TQPoint p = m_curves->getCurvePoint(i, j);
    
            if (m_originalImage.sixteenBit() && p.x() != -1)
            {
                p.setX(p.x()/255);
                p.setY(p.y()/255);
            }
    
            config->writeEntry(TQString("CurveAjustmentChannel%1Point%2").arg(i).arg(j), p);
        }
    }

    config->sync();
}

void AdjustCurveDialog::resetValues()
{
    for (int channel = 0 ; channel < 5 ; channel++)
       m_curves->curvesChannelReset(channel);

    m_curvesWidget->reset();
    m_histogramWidget->reset();
}

// Load all settings.
void AdjustCurveDialog::slotUser3()
{
    KURL loadCurvesFile;

    loadCurvesFile = KFileDialog::getOpenURL(TDEGlobalSettings::documentPath(),
                                             TQString( "*" ), this,
                                             TQString( i18n("Select Gimp Curves File to Load")) );
    if( loadCurvesFile.isEmpty() )
       return;

    if ( m_curves->loadCurvesFromGimpCurvesFile( loadCurvesFile ) == false )
    {
       KMessageBox::error(this, i18n("Cannot load from the Gimp curves text file."));
       return;
    }

    // Refresh the current curves config.
    slotChannelChanged(m_channelCB->currentItem());
    slotEffect();
}

// Save all settings.
void AdjustCurveDialog::slotUser2()
{
    KURL saveCurvesFile;

    saveCurvesFile = KFileDialog::getSaveURL(TDEGlobalSettings::documentPath(),
                                             TQString( "*" ), this,
                                             TQString( i18n("Gimp Curves File to Save")) );
    if( saveCurvesFile.isEmpty() )
       return;

    if ( m_curves->saveCurvesToGimpCurvesFile( saveCurvesFile ) == false )
    {
       KMessageBox::error(this, i18n("Cannot save to the Gimp curves text file."));
       return;
    }

    // Refresh the current curves config.
    slotChannelChanged(m_channelCB->currentItem());
}

}  // NameSpace DigikamAdjustCurvesImagesPlugin