/***************************************************************************
     SelectTimeWidget.h  -  widget for selecting a time or range
                             -------------------
    begin                : Thu Jan 16 2003
    copyright            : (C) 2002 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 SELECT_TIME_WIDGET_H
#define SELECT_TIME_WIDGET_H

#include "config.h"

#include <QtGlobal>
#include <QGroupBox>
#include <QObject>
#include <QTimer>

#include "libgui/ui_SelectTimeWidgetBase.h"
#include "libkwave/Sample.h"

namespace Kwave
{

    /**
    * widget for selecting a time or range
    */
    class Q_DECL_EXPORT SelectTimeWidget
        :public QGroupBox, public Ui::SelectTimeWidgetBase
    {
        Q_OBJECT
    public:

        /** possible mode of the selection */
        typedef enum {
            byTime = 0, /**< range in milliseconds */
            bySamples,  /**< number of samples */
            byPercents  /**< percentage of whole signal */
        } Mode;

        /**
         * Constructor
         * @param widget pointer to the parent widget
         */
        explicit SelectTimeWidget(QWidget *widget);

        /**
         * Constructor
         * @param mode selectionMode: byTime, bySamples, byPercents
         * @param range length of the selection in ms, samples or percent
         * @param sample_rate number of samples per second, needed for
         *                    converting between samples and time
         * @param offset start of the selection [samples]
         * @param signal_length length of the signal in samples, needed
         *                      for converting samples to percentage
         */
        virtual void init(Mode mode, quint64 range, double sample_rate,
                          sample_index_t offset,
                          sample_index_t signal_length);

        /** Destructor */
        virtual ~SelectTimeWidget();

        /** Sets a new selection mode */
        void setMode(Mode new_mode);

        /**
         * Returns the current selection mode (byTime, bySamples, byPercents)
         */
        Mode mode() const { return m_mode; }

        /** Returns the number of ms, samples or percents */
        quint64 time() const { return m_range; }

        /** Returns the time in units of samples */
        sample_index_t samples() const;

        /** Sets the title of the, shown in the frame around the controls */
        virtual void setTitle(const QString title);

        /**
         * Conversion from time into samples
         * @param mode time mode (byTime, bySamples, byPercents)
         * @param time a time, given in ms, samples or percents
         * @param rate number of samples per second
         * @param length signal length
         * @return time converted to samples
         */
        static sample_index_t timeToSamples(Mode mode, quint64 time,
                                            double rate, sample_index_t length);

        /**
         * Conversion from samples into time
         * @param mode time mode (byTime, bySamples, byPercents)
         * @param time position in samples
         * @param rate number of samples per second
         * @param length signal length
         * @return time converted to the given mode
         */
        static quint64 samplesToTime(Mode mode, sample_index_t time,
                                     double rate, sample_index_t length);

    signals:

        /** Emitted when the value has been changed */
        void valueChanged(sample_index_t samples);

    public slots:

        /**
         * Sets/updates the start offset from which the selection starts.
         * The current selection length will be reduced to fit in the
         * available range.
         * @param offset index of the first selected sample
         */
        void setOffset(sample_index_t offset);

    private slots:

        /** called whenever one of the radio buttons changed it's state */
        void modeChanged(bool checked);

        /** called whenever one of the time controls changed their value */
        void timeChanged(int);

        /** checks for new values in the sample edit field */
        void checkNewSampleEdit();

        /** called when sample count has changed */
        void samplesChanged(int);

        /** called when percentage changed */
        void percentsChanged(int p);

    private:

        /** connects all widgets for getting informed about changes */
        void connect();

        /** disconnect all widgets for avoiding recursion */
        void disconnect();

    private:

        /** selectionMode: byTime, bySamples or byPercent */
        Mode m_mode;

        /** selected range in ms, samples or percent */
        quint64 m_range;

        /** sample rate [samples/second] */
        double m_rate;

        /** start offset of the selection [samples] */
        sample_index_t m_offset;

        /** length of the whole signal [samples] */
        sample_index_t m_length;

        /** timer that checks for changes in the sample edit */
        QTimer m_timer;

    };
}

#endif /* SELECT_TIME_WIDGET_H */

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