/*  This file is part of the KDE project.

Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).

This library is free software: you can redistribute it and/or modify

it under the terms of the GNU Lesser General Public License as published by

the Free Software Foundation, either version 2.1 or 3 of the License.

This library 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License

along with this library.  If not, see <http://www.gnu.org/licenses/>.

*/

#ifndef PHONON_MMF_AUDIOOUTPUT_H

#define PHONON_MMF_AUDIOOUTPUT_H

#include <QHash>

#include "mmf_medianode.h"

#include <phonon/audiooutputinterface.h>

QT_BEGIN_NAMESPACE

namespace Phonon

{

namespace MMF

{

class Backend;

class VolumeObserver;

/**

 * @short AudioOutputInterface implementation for MMF.

 *

 * Forwards volume commands to the VolumeObserver instance,

 * which is provided by the backend when MediaNode objects are

 * connected.

 *

 * \section volume Volume

 *

 * Phonon's concept on volume is from 0.0 to 1.0, and from 1< it does

 * voltage multiplication. CDrmPlayerUtility goes from 1 to

 * CDrmPlayerUtility::MaxVolume(). We apply some basic math to convert

 * between the two.

 *

 * @author Frans Englich<frans.englich@nokia.com>

 */

class AudioOutput : public MediaNode

                  , public AudioOutputInterface

{

    Q_OBJECT

    Q_INTERFACES(Phonon::AudioOutputInterface)

public:

    AudioOutput(Backend *backend, QObject *parent);

    virtual qreal volume() const;

    virtual void setVolume(qreal volume);

    virtual int outputDevice() const;

    /**

     * Has no effect.

     */

    virtual bool setOutputDevice(int);

    static QHash<QByteArray, QVariant> audioOutputDescription(int index);

    enum Constants

    {

        AudioOutputDeviceID = 0

    };

protected:

    virtual bool activateOnMediaObject(MediaObject *mo);

Q_SIGNALS:

    void volumeChanged(qreal volume);

    void audioDeviceFailed();

private:

    void setVolumeObserver(VolumeObserver* observer);

    qreal                           m_volume;

    // Not owned

    VolumeObserver*                 m_observer;

};

}

}

QT_END_NAMESPACE

#endif