/* GStreamer

 * Copyright (C) 2010, 2012 Alexander Saprykin <xelfium@gmail.com>

 *

 * gsttocsetter.c: interface for TOC setting on elements

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Library General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * 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

 * Library General Public License for more details.

 *

 * You should have received a copy of the GNU Library General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

/**

 * SECTION:gsttocsetter

 * @title: GstTocSetter

 * @short_description: Element interface that allows setting and retrieval

 *                     of the TOC

 *

 * Element interface that allows setting of the TOC.

 *

 * Elements that support some kind of chapters or editions (or tracks like in

 * the FLAC cue sheet) will implement this interface.

 *

 * If you just want to retrieve the TOC in your application then all you

 * need to do is watch for TOC messages on your pipeline's bus (or you can

 * perform TOC query). This interface is only for setting TOC data, not for

 * extracting it. To set TOC from the application, find proper tocsetter element

 * and set TOC using gst_toc_setter_set_toc().

 *

 * Elements implementing the #GstTocSetter interface can extend existing TOC

 * by getting extend UID for that (you can use gst_toc_find_entry() to retrieve it)

 * with any TOC entries received from downstream.

 */

#ifdef HAVE_CONFIG_H

#  include "config.h"

#endif

#include "gst_private.h"

#include "gsttocsetter.h"

#include <gobject/gvaluecollector.h>

#include <string.h>

static GQuark gst_toc_key;

G_DEFINE_INTERFACE_WITH_CODE (GstTocSetter, gst_toc_setter, GST_TYPE_ELEMENT,

    gst_toc_key = g_quark_from_static_string ("gst-toc-setter-data"););

static void

gst_toc_setter_default_init (GstTocSetterInterface * klass)

{

  /* nothing to do here, it's a dummy interface */

}

typedef struct

{

  GstToc *toc;

  GMutex lock;

} GstTocData;

static void

gst_toc_data_free (gpointer p)

{

  GstTocData *data = (GstTocData *) p;

  if (data->toc)

    gst_toc_unref (data->toc);

  g_mutex_clear (&data->lock);

  g_slice_free (GstTocData, data);

}

static GstTocData *

gst_toc_setter_get_data (GstTocSetter * setter)

{

  GstTocData *data;

  data = g_object_get_qdata (G_OBJECT (setter), gst_toc_key);

  if (!data) {

    static GMutex create_mutex;

    /* make sure no other thread is creating a GstTocData at the same time */

    g_mutex_lock (&create_mutex);

    data = g_object_get_qdata (G_OBJECT (setter), gst_toc_key);

    if (!data) {

      data = g_slice_new (GstTocData);

      g_mutex_init (&data->lock);

      data->toc = NULL;

      g_object_set_qdata_full (G_OBJECT (setter), gst_toc_key, data,

          gst_toc_data_free);

    }

    g_mutex_unlock (&create_mutex);

  }

  return data;

}

/**

 * gst_toc_setter_reset:

 * @setter: a #GstTocSetter.

 *

 * Reset the internal TOC. Elements should call this from within the

 * state-change handler.

 */

void

gst_toc_setter_reset (GstTocSetter * setter)

{

  g_return_if_fail (GST_IS_TOC_SETTER (setter));

  gst_toc_setter_set_toc (setter, NULL);

}

/**

 * gst_toc_setter_get_toc:

 * @setter: a #GstTocSetter.

 *

 * Return current TOC the setter uses. The TOC should not be

 * modified without making it writable first.

 *

 * Returns: (transfer full) (nullable): TOC set, or %NULL. Unref with

 *     gst_toc_unref() when no longer needed

 */

GstToc *

gst_toc_setter_get_toc (GstTocSetter * setter)

{

  GstTocData *data;

  GstToc *ret = NULL;

  g_return_val_if_fail (GST_IS_TOC_SETTER (setter), NULL);

  data = gst_toc_setter_get_data (setter);

  g_mutex_lock (&data->lock);

  if (data->toc != NULL)

    ret = gst_toc_ref (data->toc);

  g_mutex_unlock (&data->lock);

  return ret;

}

/**

 * gst_toc_setter_set_toc:

 * @setter: a #GstTocSetter.

 * @toc: (allow-none): a #GstToc to set.

 *

 * Set the given TOC on the setter. Previously set TOC will be

 * unreffed before setting a new one.

 */

void

gst_toc_setter_set_toc (GstTocSetter * setter, GstToc * toc)

{

  GstTocData *data;

  g_return_if_fail (GST_IS_TOC_SETTER (setter));

  data = gst_toc_setter_get_data (setter);

  g_mutex_lock (&data->lock);

  if (data->toc != toc) {

    if (data->toc)

      gst_toc_unref (data->toc);

    data->toc = (toc) ? gst_toc_ref (toc) : NULL;

  }

  g_mutex_unlock (&data->lock);

}