/*************************************************************************
        ReversePlugin.h  -  reverses the current selection
                             -------------------
    begin                : Tue Jun 09 2009
    copyright            : (C) 2009 by Thomas Eschenbacher
    email                : Thomas.Eschenbacher@gmx.de
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/

#ifndef REVERSE_PLUGIN_H
#define REVERSE_PLUGIN_H

#include "config.h"

#include <QString>
#include <QStringList>

#include "libkwave/Plugin.h"
#include "libkwave/Sample.h"
#include "libkwave/SampleArray.h"

namespace Kwave
{
    /**
     * @class ReversePlugin
     * Reverses the current selection by exchanging blocks of samples
     * from front and back and reversing their content
     */
    class ReversePlugin: public Kwave::Plugin
    {
        Q_OBJECT

    public:

        /**
         * Constructor
         * @param parent reference to our plugin manager
         * @param args argument list [unused]
         */
        ReversePlugin(QObject *parent, const QVariantList &args);

        /** Destructor */
        virtual ~ReversePlugin() Q_DECL_OVERRIDE;

        /**
         * reverses the selection
         * @param params list of strings with parameters
         */
        virtual void run(QStringList params) Q_DECL_OVERRIDE;

    private slots:

        /**
         * multiplies the progress by factor two and
         * calls Kwave::Plugin::updateProgress
         */
        virtual void updateProgress(qreal progress) Q_DECL_OVERRIDE;

    private:

        /**
         * common slice parameters, which can be passed to all worker
         * threads
         */
        typedef struct {
            sample_index_t m_first;      /**< index of the first sample */
            sample_index_t m_last;       /**< index of the last sample  */
            unsigned int   m_block_size; /**< block size [samples]      */
        } SliceParams;

        /**
         * reverse a slice of samples
         * @param track index of the track
         * @param src_a reader for reading from the start (forward)
         * @param src_b reader fro reading from the end (backwards)
         * @param params common slice parameters (first/last/block size)
         */
        void reverseSlice(unsigned int track,
                          Kwave::SampleReader *src_a,
                          Kwave::SampleReader *src_b,
                          const Kwave::ReversePlugin::SliceParams &params);

        /** reverses the content of an array of samples */
        void reverse(Kwave::SampleArray &buffer);

    };
}

#endif /* REVERSE_PLUGIN_H */

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