/* GStreamer

 * Copyright (C) 2015 Sebastian Dröge <sebastian@centricular.com>

 *

 * 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.

 */

#include "gstrtputils.h"

typedef struct

{

  GstElement *element;

  GstBuffer *outbuf;

  GQuark copy_tag;

} CopyMetaData;

GQuark rtp_quark_meta_tag_video;

GQuark rtp_quark_meta_tag_audio;

static gboolean

foreach_metadata_copy (GstBuffer * inbuf, GstMeta ** meta, gpointer user_data)

{

  CopyMetaData *data = user_data;

  GstElement *element = data->element;

  GstBuffer *outbuf = data->outbuf;

  GQuark copy_tag = data->copy_tag;

  const GstMetaInfo *info = (*meta)->info;

  const gchar *const *tags = gst_meta_api_type_get_tags (info->api);

  if (!tags || (copy_tag != 0 && g_strv_length ((gchar **) tags) == 1

          && gst_meta_api_type_has_tag (info->api, copy_tag))) {

    GstMetaTransformCopy copy_data = { FALSE, 0, -1 };

    GST_DEBUG_OBJECT (element, "copy metadata %s", g_type_name (info->api));

    /* simply copy then */

    info->transform_func (outbuf, *meta, inbuf,

        _gst_meta_transform_copy, &copy_data);

  } else {

    GST_DEBUG_OBJECT (element, "not copying metadata %s",

        g_type_name (info->api));

  }

  return TRUE;

}

/* TODO: Should probably make copy_tag an array at some point */

void

gst_rtp_copy_meta (GstElement * element, GstBuffer * outbuf, GstBuffer * inbuf,

    GQuark copy_tag)

{

  CopyMetaData data = { element, outbuf, copy_tag };

  gst_buffer_foreach_meta (inbuf, foreach_metadata_copy, &data);

}

void

gst_rtp_copy_video_meta (gpointer element, GstBuffer * outbuf,

    GstBuffer * inbuf)

{

  gst_rtp_copy_meta (element, outbuf, inbuf, rtp_quark_meta_tag_video);

}

void

gst_rtp_copy_audio_meta (gpointer element, GstBuffer * outbuf,

    GstBuffer * inbuf)

{

  gst_rtp_copy_meta (element, outbuf, inbuf, rtp_quark_meta_tag_audio);

}

typedef struct

{

  GstElement *element;

  GQuark keep_tag;

} DropMetaData;

static gboolean

foreach_metadata_drop (GstBuffer * inbuf, GstMeta ** meta, gpointer user_data)

{

  DropMetaData *data = user_data;

  GstElement *element = data->element;

  GQuark keep_tag = data->keep_tag;

  const GstMetaInfo *info = (*meta)->info;

  const gchar *const *tags = gst_meta_api_type_get_tags (info->api);

  if (!tags || (keep_tag != 0 && g_strv_length ((gchar **) tags) == 1

          && gst_meta_api_type_has_tag (info->api, keep_tag))) {

    GST_DEBUG_OBJECT (element, "keeping metadata %s", g_type_name (info->api));

  } else {

    GST_DEBUG_OBJECT (element, "dropping metadata %s", g_type_name (info->api));

    *meta = NULL;

  }

  return TRUE;

}

/* TODO: Should probably make keep_tag an array at some point */

void

gst_rtp_drop_meta (GstElement * element, GstBuffer * buf, GQuark keep_tag)

{

  DropMetaData data = { element, keep_tag };

  gst_buffer_foreach_meta (buf, foreach_metadata_drop, &data);

}

void

gst_rtp_drop_non_audio_meta (gpointer element, GstBuffer * buf)

{

  gst_rtp_drop_meta (element, buf, rtp_quark_meta_tag_audio);

}

void

gst_rtp_drop_non_video_meta (gpointer element, GstBuffer * buf)

{

  gst_rtp_drop_meta (element, buf, rtp_quark_meta_tag_video);

}

/* Stolen from bad/gst/mpegtsdemux/payloader_parsers.c */

/* variable length Exp-Golomb parsing according to H.265 spec section 9.2*/

gboolean

gst_rtp_read_golomb (GstBitReader * br, guint32 * value)

{

  guint8 b, leading_zeros = -1;

  *value = 1;

  for (b = 0; !b; leading_zeros++) {

    if (!gst_bit_reader_get_bits_uint8 (br, &b, 1))

      return FALSE;

    *value *= 2;

  }

  *value = (*value >> 1) - 1;

  if (leading_zeros > 0) {

    guint32 tmp = 0;

    if (!gst_bit_reader_get_bits_uint32 (br, &tmp, leading_zeros))

      return FALSE;

    *value += tmp;

  }

  return TRUE;

}