/**

       Copyright (C) 2005  Matthieu CASTET, Alex Beregszaszi

 
       Permission is hereby granted, free of charge, to any person
       obtaining a copy of this software and associated documentation
       files (the "Software"), to deal in the Software without
       restriction, including without limitation the rights to use, copy,
       modify, merge, publish, distribute, sublicense, and/or sell copies
       of the Software, and to permit persons to whom the Software is
       furnished to do so, subject to the following conditions:
 
       The above copyright notice and this permission notice shall be
       included in all copies or substantial portions of the Software.
 
       THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
       EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
       MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
       NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
       HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
       WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
       OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
       DEALINGS IN THE SOFTWARE.
 **/
 
 #include <stdlib.h>

 #include "libavutil/bswap.h"

 #include "libavcodec/get_bits.h"

 #include "avformat.h"

 #include "internal.h"

 #include "oggdec.h"

 struct theora_params {

     int gpshift;
     int gpmask;

     unsigned version;

 };

 
 static int
 theora_header (AVFormatContext * s, int idx)
 {

     struct ogg *ogg = s->priv_data;
     struct ogg_stream *os = ogg->streams + idx;

     AVStream *st = s->streams[idx];

     struct theora_params *thp = os->private;

     int cds = st->codec->extradata_size + os->psize + 2, err;

     uint8_t *cdp;
 

     if(!(os->buf[os->pstart] & 0x80))

         return 0;
 
     if(!thp){

         thp = av_mallocz(sizeof(*thp));
         os->private = thp;

     }
 

     switch (os->buf[os->pstart]) {
     case 0x80: {

         GetBitContext gb;

         int width, height;

         AVRational timebase;

         init_get_bits(&gb, os->buf + os->pstart, os->psize*8);
 

         skip_bits_long(&gb, 7*8); /* 0x80"theora" */

         thp->version = get_bits_long(&gb, 24);
         if (thp->version < 0x030100)

         {
             av_log(s, AV_LOG_ERROR,

                 "Too old or unsupported Theora (%x)\n", thp->version);

             return -1;

         }

         width  = get_bits(&gb, 16) << 4;
         height = get_bits(&gb, 16) << 4;
         avcodec_set_dimensions(st->codec, width, height);

         if (thp->version >= 0x030400)

             skip_bits(&gb, 100);
 

         if (thp->version >= 0x030200) {

             width  = get_bits_long(&gb, 24);
             height = get_bits_long(&gb, 24);
             if (   width  <= st->codec->width  && width  > st->codec->width-16
                 && height <= st->codec->height && height > st->codec->height-16)
                 avcodec_set_dimensions(st->codec, width, height);

 
             skip_bits(&gb, 16);

         }

         timebase.den = get_bits_long(&gb, 32);
         timebase.num = get_bits_long(&gb, 32);
         if (!(timebase.num > 0 && timebase.den > 0)) {

             av_log(s, AV_LOG_WARNING, "Invalid time base in theora stream, assuming 25 FPS\n");

             timebase.num = 1;
             timebase.den = 25;

         }

         avpriv_set_pts_info(st, 64, timebase.num, timebase.den);

         st->sample_aspect_ratio.num = get_bits_long(&gb, 24);
         st->sample_aspect_ratio.den = get_bits_long(&gb, 24);

         if (thp->version >= 0x030200)

             skip_bits_long(&gb, 38);

         if (thp->version >= 0x304000)

             skip_bits(&gb, 2);
 

         thp->gpshift = get_bits(&gb, 5);

         thp->gpmask = (1 << thp->gpshift) - 1;

         st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

         st->codec->codec_id = AV_CODEC_ID_THEORA;

         st->need_parsing = AVSTREAM_PARSE_HEADERS;

     }
     break;
     case 0x81:

         ff_vorbis_comment(s, &st->metadata, os->buf + os->pstart + 7, os->psize - 7);

     case 0x82:
         if (!thp->version)
             return -1;
         break;
     default:

         av_log(s, AV_LOG_ERROR, "Unknown header type %X\n", os->buf[os->pstart]);

         return -1;

     }
 

     if ((err = av_reallocp(&st->codec->extradata,

                            cds + FF_INPUT_BUFFER_PADDING_SIZE)) < 0) {
         st->codec->extradata_size = 0;

         return err;

     }

     cdp = st->codec->extradata + st->codec->extradata_size;

     *cdp++ = os->psize >> 8;
     *cdp++ = os->psize & 0xff;
     memcpy (cdp, os->buf + os->pstart, os->psize);

     st->codec->extradata_size = cds;

     return 1;

 }
 
 static uint64_t

 theora_gptopts(AVFormatContext *ctx, int idx, uint64_t gp, int64_t *dts)

 {

     struct ogg *ogg = ctx->priv_data;
     struct ogg_stream *os = ogg->streams + idx;
     struct theora_params *thp = os->private;

     uint64_t iframe, pframe;
 
     if (!thp)
         return AV_NOPTS_VALUE;
 
     iframe = gp >> thp->gpshift;
     pframe = gp & thp->gpmask;

     if (thp->version < 0x030201)
         iframe++;
 

     if(!pframe)

         os->pflags |= AV_PKT_FLAG_KEY;

     if (dts)
         *dts = iframe + pframe;
 

     return iframe + pframe;

 }
 

 static int theora_packet(AVFormatContext *s, int idx)
 {
     struct ogg *ogg = s->priv_data;
     struct ogg_stream *os = ogg->streams + idx;
     int duration;
 
     /* first packet handling
        here we parse the duration of each packet in the first page and compare
        the total duration to the page granule to find the encoder delay and
        set the first timestamp */
 

     if ((!os->lastpts || os->lastpts == AV_NOPTS_VALUE) && !(os->flags & OGG_FLAG_EOS)) {

         int seg;

 
         duration = 1;
         for (seg = os->segp; seg < os->nsegs; seg++) {
             if (os->segments[seg] < 255)
                 duration ++;

         }

         os->lastpts = os->lastdts   = theora_gptopts(s, idx, os->granule, NULL) - duration;

         if(s->streams[idx]->start_time == AV_NOPTS_VALUE) {
             s->streams[idx]->start_time = os->lastpts;
             if (s->streams[idx]->duration)
                 s->streams[idx]->duration -= s->streams[idx]->start_time;
         }

     }
 
     /* parse packet duration */
     if (os->psize > 0) {
         os->pduration = 1;
     }
 
     return 0;
 }
 

 const struct ogg_codec ff_theora_codec = {

     .magic = "\200theora",
     .magicsize = 7,
     .header = theora_header,

     .packet = theora_packet,

     .gptopts = theora_gptopts,
     .nb_header = 3,

 };