/*  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/>.

*/

#include "audiooutput.h"

#include "mediaobject.h"

#include <QtCore/qmath.h>

QT_BEGIN_NAMESPACE

namespace Phonon

{

    namespace DS9

    {

        AudioOutput::AudioOutput(Backend *back, QObject *parent)

            : BackendNode(parent), m_currentIndex(0), m_crossfadeProgress(1.),

              m_device(-1), m_backend(back), m_volume(0.)

        {

        }

        AudioOutput::~AudioOutput()

        {

        }

        int AudioOutput::outputDevice() const

        {

            return m_device;

        }

        static const qreal log10over20 = qreal(0.1151292546497022842); // ln(10) / 20

        void AudioOutput::setVolume(qreal newVolume)

        {

            for(int i = 0; i < FILTER_COUNT; ++i) {

                ComPointer<IBasicAudio> audio(m_filters[i], IID_IBasicAudio);

                if (audio) {

                    const qreal currentVolume = newVolume * (m_currentIndex == i ? m_crossfadeProgress : 1-m_crossfadeProgress);

                    const qreal newDbVolume = (qMax(0., 1.-::log(::pow(currentVolume, -log10over20)))-1.) * 10000;

                    audio->put_Volume(qRound(newDbVolume));

                }

            }

            if (m_volume != newVolume) {

                m_volume = newVolume;

                emit volumeChanged(newVolume);

            }

        }

        void AudioOutput::setCrossFadingProgress(short currentIndex, qreal progress)

        {

            m_crossfadeProgress = progress;

            m_currentIndex = currentIndex;

            setVolume(m_volume);

        }

        bool AudioOutput::setOutputDevice(const AudioOutputDevice & newDevice)

        {

            //stub implementation

            return setOutputDevice(newDevice.index());

        }

        qreal AudioOutput::volume() const

        {

            return m_volume;

        }

        bool AudioOutput::setOutputDevice(int newDevice)

        {

            if (newDevice == m_device) {

                return true;

            }

            //free the previous one if it was already set

            for(int i = 0; i < FILTER_COUNT; ++i) {

                const Filter &oldFilter = m_filters[i];

                Filter newFilter = m_backend->getAudioOutputFilter(newDevice);

                if (m_mediaObject && oldFilter && newFilter) {

                    m_mediaObject->switchFilters(i, oldFilter, newFilter);

                }

                m_filters[i] = newFilter; 

            }

            m_device = newDevice;

            setVolume(m_volume);

            return true;

        }

    }

}

QT_END_NAMESPACE

#include "moc_audiooutput.cpp"