/*

  * Xiph CELT parser for Ogg

  * Copyright (c) 2011 Nicolas George
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg 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 of the License, or (at your option) any later version.
  *
  * FFmpeg 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 FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include <string.h>

 
 #include "libavutil/intreadwrite.h"

 #include "avformat.h"

 #include "internal.h"

 #include "oggdec.h"
 
 struct oggcelt_private {
     int extra_headers_left;
 };
 
 static int celt_header(AVFormatContext *s, int idx)
 {
     struct ogg *ogg = s->priv_data;
     struct ogg_stream *os = ogg->streams + idx;
     AVStream *st = s->streams[idx];
     struct oggcelt_private *priv = os->private;
     uint8_t *p = os->buf + os->pstart;
 
     if (os->psize == 60 &&
         !memcmp(p, ff_celt_codec.magic, ff_celt_codec.magicsize)) {
         /* Main header */
 

         uint32_t version, sample_rate, nb_channels;

         uint32_t overlap, extra_headers;

 
         priv = av_malloc(sizeof(struct oggcelt_private));

         if (!priv)
             return AVERROR(ENOMEM);

         if (ff_alloc_extradata(st->codecpar, 2 * sizeof(uint32_t)) < 0) {

             av_free(priv);

             return AVERROR(ENOMEM);

         }

         version          = AV_RL32(p + 28);

         /* unused header size field skipped */

         sample_rate      = AV_RL32(p + 36);
         nb_channels      = AV_RL32(p + 40);
         overlap          = AV_RL32(p + 48);

         /* unused bytes per packet field skipped */

         extra_headers    = AV_RL32(p + 56);

         st->codecpar->codec_type     = AVMEDIA_TYPE_AUDIO;
         st->codecpar->codec_id       = AV_CODEC_ID_CELT;
         st->codecpar->sample_rate    = sample_rate;
         st->codecpar->channels       = nb_channels;

         if (sample_rate)

             avpriv_set_pts_info(st, 64, 1, sample_rate);

 
         if (os->private) {
             av_free(priv);
             priv = os->private;
         }

         os->private = priv;

         priv->extra_headers_left  = 1 + extra_headers;
 

         AV_WL32(st->codecpar->extradata + 0, overlap);
         AV_WL32(st->codecpar->extradata + 4, version);

         return 1;

     } else if (priv && priv->extra_headers_left) {

         /* Extra headers (vorbiscomment) */
 

         ff_vorbis_stream_comment(s, st, p, os->psize);

         priv->extra_headers_left--;
         return 1;
     } else {
         return 0;
     }
 }
 
 const struct ogg_codec ff_celt_codec = {
     .magic     = "CELT    ",
     .magicsize = 8,
     .header    = celt_header,

     .nb_header = 2,

 };