/****************************************************************************************

 * Copyright (c) 2008 Nikolaj Hald Nielsen <nhn@kde.org>                                *

 * Copyright (c) 2008 Jeff Mitchell <kde-dev@emailgoeshere.com>                         *

 * Copyright (c) 2009 Mark Kretschmann <kretschmann@kde.org>                            *

 *                                                                                      *

 * 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.                                                                             *

 *                                                                                      *

 * 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.             *

 *                                                                                      *

 * You should have received a copy of the GNU General Public License along with         *

 * this program.  If not, see <http://www.gnu.org/licenses/>.                           *

 ****************************************************************************************/

#ifndef SVGHANDLER_H

#define SVGHANDLER_H

class QStyleOptionSlider;

#include "amarok_export.h"

#include "core/meta/Meta.h"

#include <KPixmapCache>

#include <QReadWriteLock>

#include <KSvgRenderer>

#include <QPixmap>

#include <QString>

class SvgHandler;

namespace The {

    AMAROK_EXPORT SvgHandler* svgHandler();

}

/**

A class to abstract out some common operations of users of tinted svgs

*/

class AMAROK_EXPORT SvgHandler : public QObject

{

    Q_OBJECT

    friend SvgHandler* The::svgHandler();

    public:

        ~SvgHandler();

        KSvgRenderer* getRenderer( const QString &name );

        KSvgRenderer* getRenderer();

        QPixmap renderSvg( const QString &name, const QString& keyname, int width, int height, const QString& element = QString(), bool skipCache = false );

        /**

        * Overloaded function that uses the current theme

        * @param keyname the name of the key to save in the cache

        * @param width Width of the resulting pixmap

        * @param height Height of the resulting pixmap

        * @param element The theme element to render ( if none the entire svg is rendered )

        * @param skipCache If true, the pixmap will always get rendered and never fetched from the cache.

        * @return The svg element/file rendered into a pixmap

        */

        QPixmap renderSvg( const QString& keyname, int width, int height, const QString& element = QString(), bool skipCache = false );

        /**

         * Yet another overloaded function. This one renders the svg element and adds half a divider element to the top and the bottom

         * so it looks sane when multiple elements with the same width are stacked.

         *

         * @param keyname the name of the key to save in the cache.

         * @param width Width of the resulting pixmap.

         * @param height Height of the resulting pixmap.

         * @param element The theme element to render ( if none the entire svg is rendered )

         * @return The svg element/file rendered into a pixmap.

         */

        QPixmap renderSvgWithDividers( const QString& keyname, int width, int height, const QString& element = QString() );

        /**

         * Take an album and extract the pixmap for sending to addBordersToPixmap.

         *

         * @param album The AlbumPtr

         * @param size Some size or another

         * @borderWidth The desired width of the border

         */

        QPixmap imageWithBorder( Meta::AlbumPtr album, int size = 1, int borderWidth = 5 );

        /**

         * Add nice borders to a pixmap. The function will create and return a new

         * Pixmal that is the size of the old one plus twice the border width in

         * each dimension.

         * 

         * @param orgPixmap The original pixmap.

         * @param borderWidth The pixel width of the borders to add to the pixmap. 

         * @param name A name for use as the basis of the cache key that for caching the completed image plus borders.

         * @param skipCache If true, the pixmap will always get rendered and never fetched from the cache.

         */

        QPixmap addBordersToPixmap( QPixmap orgPixmap, int borderWidth, const QString &name, bool skipCache =false );

        /**

         * Paint a custom slider using the specified painter. The slider consists

         * of a background part, a "knob" that moves along it to show the current

         * position, and 2 end markers to clearly mark the ends of the slider.

         * The background part before the knob, is painted in a different color than the

         * part after (and under) the knob.

         * @param p The painter to use.

         * @param x The x position to begin painting at.

         * @param y The y position to begin painting at.

         * @param width The width of the slider to paint.

         * @param height The height of the slider. The background part does not scale in height, it will always be a relatively thin line, but the knob and end markers do.

         * @param percentage The percentange of the slider that the knob is positioned at.

         * @param active Specifies whether the slider should be painted "active" using the current palettes active colors, to specify that it currently has mouse focus or hover.

         */

        void paintCustomSlider( QPainter *p, QStyleOptionSlider *slider, qreal percentage, bool paintMoodbar  = false );

        /**

         * Calculate the visual slider knob rect from its value, use it instead the QStyle functions

         * QStyle::sliderPositionFromValue() and QStyle::subControlRect();

         */

        QRect sliderKnobRect( const QRect &slider, qreal percent, bool inverse ) const;

        /**

         * Get the path of the currently used svg theme file.

         *

         * @return the path of the currently used theme file.

         */

        QString themeFile();

        /**

         * Change the currently used svg theme file. This function also

         * clears the pixmap cache as all svg elements have potentially changed

         * and should be re-rendered.

         *

         * @param themeFile The path of the new theme file to use.

         */

        void setThemeFile( const QString  & themeFile );

    public slots:

        void reTint();

    signals:

        void retinted();

    private slots:

        void discardCache();

    private:

        SvgHandler( QObject* parent = 0 );

        bool loadSvg( const QString& name );

        QPixmap sliderHandle( const QColor &color, bool pressed, int size );

        QColor calcLightColor(const QColor &color) const;

        QColor calcDarkColor(const QColor &color) const;

        bool lowThreshold(const QColor &color) const;

        KPixmapCache * m_cache;

        KPixmapCache * m_sliderHandleCache;

        QHash<QString,KSvgRenderer*> m_renderers;

        QReadWriteLock m_lock;

        QString m_themeFile;

        bool m_customTheme;

};

#endif