/*  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_ABSTRACTEFFECT_H

#define PHONON_MMF_ABSTRACTEFFECT_H

#include "mmf_medianode.h"

#include <QScopedPointer>

#include <AudioEffectBase.h>

#include <Phonon/EffectInterface>

#include <Phonon/EffectParameter>

#include "audioplayer.h"

QT_BEGIN_NAMESPACE

namespace Phonon

{

namespace MMF

{

/**

 * @short Base class for all effects for MMF.

 *

 * Adhering to Phonon with MMF is cumbersome because of a number of reasons:

 *

 * - MMF has no concept of effect chaining. Simply, an effect is a applied

 *   to PlayerUtility, that's it. This means that the order of effects is

 *   undefined.

 * - We apply an effect to a PlayerUtility, and MediaObject has that one.

 *   However, effects might be created before MediaObject, but nevertheless

 *   needs to work. We solve this by that we are aware of the whole connection

 *   chain, and whenever a connection happens, we walk the chain, find effects

 *   that aren't applied, and apply it if we have a media object.

 * - There are plenty of corner cases which we don't handle and where behavior

 *   are undefined. For instance, graphs with more than one MediaObject.

 */

class AbstractAudioEffect : public MediaNode

                          , public EffectInterface

{

    Q_OBJECT

    Q_INTERFACES(Phonon::EffectInterface)

public:

    AbstractAudioEffect(QObject *parent,

                        const QList<EffectParameter> &params);

    virtual QList<EffectParameter> parameters() const;

    virtual QVariant parameterValue(const EffectParameter &param) const;

    virtual void setParameterValue(const EffectParameter &,

                                   const QVariant &newValue);

    virtual bool disconnectMediaNode(MediaNode *target);

    enum Type

    {

        EffectAudioEqualizer = 1,

        EffectBassBoost,

        EffectDistanceAttenuation,

        EffectEnvironmentalReverb,

        EffectListenerOrientation,

        EffectLoudness,

        EffectSourceOrientation,

        EffectStereoWidening

    };

protected:

    virtual bool activateOn(CPlayerType *player) = 0;

    virtual void parameterChanged(const int id,

                                  const QVariant &value) = 0;

    /**

     * Part of the implementation of AbstractAudioEffect. Forwards the call to

     * activateOn(), essentially.

     */

    virtual bool activateOnMediaObject(MediaObject *mo);

    QScopedPointer<CAudioEffect>    m_effect;

private:

    const QList<EffectParameter>    m_params;

    QHash<int, QVariant>            m_values;

};

}

}

QT_END_NAMESPACE

#endif