/*
  * Copyright (C) 2008  David Conrad
  *
  * 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 "libavcodec/get_bits.h"
 #include "libavcodec/dirac.h"
 #include "avformat.h"
 #include "oggdec.h"
 
 static int dirac_header(AVFormatContext *s, int idx)
 {
     struct ogg *ogg = s->priv_data;
     struct ogg_stream *os = ogg->streams + idx;
     AVStream *st = s->streams[idx];
     dirac_source_params source;
     GetBitContext gb;
 
     // already parsed the header
     if (st->codec->codec_id == CODEC_ID_DIRAC)
         return 0;
 
     init_get_bits(&gb, os->buf + os->pstart + 13, (os->psize - 13) * 8);
     if (ff_dirac_parse_sequence_header(st->codec, &gb, &source) < 0)
         return -1;
 

     st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

     st->codec->codec_id = CODEC_ID_DIRAC;
     // dirac in ogg always stores timestamps as though the video were interlaced

     av_set_pts_info(st, 64, st->codec->time_base.num, 2*st->codec->time_base.den);

     return 1;
 }
 
 // various undocument things: granule is signed (only for dirac!)

 static uint64_t dirac_gptopts(AVFormatContext *s, int idx, uint64_t granule,

                               int64_t *dts_out)

 {

     int64_t gp = granule;

     struct ogg *ogg = s->priv_data;
     struct ogg_stream *os = ogg->streams + idx;
 
     unsigned dist  = ((gp >> 14) & 0xff00) | (gp & 0xff);
     int64_t  dts   = (gp >> 31);
     int64_t  pts   = dts + ((gp >> 9) & 0x1fff);
 
     if (!dist)

         os->pflags |= AV_PKT_FLAG_KEY;

     if (dts_out)
         *dts_out = dts;
 

     return pts;
 }
 
 static int old_dirac_header(AVFormatContext *s, int idx)
 {
     struct ogg *ogg = s->priv_data;
     struct ogg_stream *os = ogg->streams + idx;
     AVStream *st = s->streams[idx];
     uint8_t *buf = os->buf + os->pstart;
 
     if (buf[0] != 'K')
         return 0;
 

     st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

     st->codec->codec_id = CODEC_ID_DIRAC;

     av_set_pts_info(st, 64, AV_RB32(buf+12), AV_RB32(buf+8));

     return 1;
 }
 

 static uint64_t old_dirac_gptopts(AVFormatContext *s, int idx, uint64_t gp,
                                   int64_t *dts)

 {
     struct ogg *ogg = s->priv_data;
     struct ogg_stream *os = ogg->streams + idx;
     uint64_t iframe = gp >> 30;
     uint64_t pframe = gp & 0x3fffffff;
 
     if (!pframe)

         os->pflags |= AV_PKT_FLAG_KEY;

 
     return iframe + pframe;
 }
 
 const struct ogg_codec ff_dirac_codec = {
     .magic = "BBCD\0",
     .magicsize = 5,
     .header = dirac_header,
     .gptopts = dirac_gptopts,
     .granule_is_start = 1,
 };
 
 const struct ogg_codec ff_old_dirac_codec = {
     .magic = "KW-DIRAC",
     .magicsize = 8,
     .header = old_dirac_header,
     .gptopts = old_dirac_gptopts,
     .granule_is_start = 1,
 };