/*  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 <gst/interfaces/propertyprobe.h>

#include <gst/gst.h>

#include "common.h"

#include "gsthelper.h"

#include <QtCore/QList>

QT_BEGIN_NAMESPACE

namespace Phonon

{

namespace Gstreamer

{

/**

 * Probes a gstElement for a list of settable string-property values

 *

 * @return a QStringList containing a list of allwed string values for the given

 *           element

 */

QList<QByteArray> GstHelper::extractProperties(GstElement *elem, const QByteArray &value)

{

    Q_ASSERT(elem);

    QList<QByteArray> list;

    if (GST_IS_PROPERTY_PROBE(elem)) {

        GstPropertyProbe *probe = GST_PROPERTY_PROBE(elem);

        const GParamSpec *devspec = 0;

        GValueArray *array = NULL;

        if ((devspec = gst_property_probe_get_property (probe, value))) {

            if ((array = gst_property_probe_probe_and_get_values (probe, devspec))) {

                for (unsigned int device = 0; device < array->n_values; device++) {

                    GValue *deviceId = g_value_array_get_nth (array, device);

                    list.append(g_value_get_string(deviceId));

                }

            }

            if (array)

                g_value_array_free (array);

        }

    }

    return list;

}

/**

 * Sets the string value of a GstElement's property

 *

 * @return false if the value could not be set.

 */

bool GstHelper::setProperty(GstElement *elem, const char *propertyName, const QByteArray &propertyValue)

{

    Q_ASSERT(elem);

    Q_ASSERT(propertyName && strlen(propertyName));

    if (GST_IS_PROPERTY_PROBE(elem) && gst_property_probe_get_property( GST_PROPERTY_PROBE( elem), propertyName ) ) {

        g_object_set(G_OBJECT(elem), propertyName, propertyValue.constData(), (const char*)NULL);

        return true;

    }

    return false;

}

/**

 * Queries an element for the value of an object property

 */

QByteArray GstHelper::property(GstElement *elem, const char *propertyName)

{

    Q_ASSERT(elem);

    Q_ASSERT(propertyName && strlen(propertyName));

    QByteArray retVal;

    if (GST_IS_PROPERTY_PROBE(elem) && gst_property_probe_get_property( GST_PROPERTY_PROBE(elem), propertyName)) {

        gchar *value = NULL;

        g_object_get (G_OBJECT(elem), propertyName, &value, (const char*)NULL);

        retVal = QByteArray(value);

        g_free (value);

    }

    return retVal;

}

/**

 * Queries a GstObject for it's name

 */

QByteArray GstHelper::name(GstObject *obj)

{

    Q_ASSERT(obj);

    QByteArray retVal;

    gchar *value = NULL;

    if ((value = gst_object_get_name (obj))) {

        retVal = QByteArray(value);

        g_free (value);

    }

    return retVal;

}

/***

 * Creates an instance of a playbin with "audio-src" and

 * "video-src" ghost pads to allow redirected output streams.

 *

 * ### This function is probably not required now that MediaObject is based

 *     on decodebin directly.

 */

GstElement* GstHelper::createPluggablePlaybin()

{

    GstElement *playbin = 0;

    //init playbin and add to our pipeline

    playbin = gst_element_factory_make("playbin", NULL);

    //Create an identity element to redirect sound

    GstElement *audioSinkBin =  gst_bin_new (NULL);

    GstElement *audioPipe = gst_element_factory_make("identity", NULL);

    gst_bin_add(GST_BIN(audioSinkBin), audioPipe);

    //Create a sinkpad on the identity

    GstPad *audiopad = gst_element_get_pad (audioPipe, "sink");

    gst_element_add_pad (audioSinkBin, gst_ghost_pad_new ("sink", audiopad));

    gst_object_unref (audiopad);

    //Create an "audio_src" source pad on the playbin

    GstPad *audioPlaypad = gst_element_get_pad (audioPipe, "src");

    gst_element_add_pad (playbin, gst_ghost_pad_new ("audio_src", audioPlaypad));

    gst_object_unref (audioPlaypad);

    //Done with our audio redirection

    g_object_set (G_OBJECT(playbin), "audio-sink", audioSinkBin, (const char*)NULL);

    // * * Redirect video to "video_src" pad : * *

    //Create an identity element to redirect sound

    GstElement *videoSinkBin =  gst_bin_new (NULL);

    GstElement *videoPipe = gst_element_factory_make("identity", NULL);

    gst_bin_add(GST_BIN(videoSinkBin), videoPipe);

    //Create a sinkpad on the identity

    GstPad *videopad = gst_element_get_pad (videoPipe, "sink");

    gst_element_add_pad (videoSinkBin, gst_ghost_pad_new ("sink", videopad));

    gst_object_unref (videopad);

    //Create an "audio_src" source pad on the playbin

    GstPad *videoPlaypad = gst_element_get_pad (videoPipe, "src");

    gst_element_add_pad (playbin, gst_ghost_pad_new ("video_src", videoPlaypad));

    gst_object_unref (videoPlaypad);

    //Done with our video redirection

    g_object_set (G_OBJECT(playbin), "video-sink", videoSinkBin, (const char*)NULL);

    return playbin;

}

} //namespace Gstreamer

} //namespace Phonon

QT_END_NAMESPACE