/*
  * XVAG demuxer
  * Copyright (c) 2015 Paul B Mahol
  *
  * 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 "libavutil/bswap.h"

 #include "libavcodec/internal.h"

 #include "avformat.h"
 #include "internal.h"
 
 static int xvag_probe(AVProbeData *p)
 {
     if (memcmp(p->buf, "XVAG", 4) ||
         memcmp(p->buf+32, "fmat", 4))
         return 0;
 
     return AVPROBE_SCORE_MAX;
 }
 
 static int xvag_read_header(AVFormatContext *s)
 {
     unsigned offset, big_endian, codec;
     AVStream *st;
 
     avio_skip(s->pb, 4);
 
     st = avformat_new_stream(s, NULL);
     if (!st)
         return AVERROR(ENOMEM);
 

     st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;

 
     offset     = avio_rl32(s->pb);
     big_endian = offset > av_bswap32(offset);
     if (big_endian) {
         offset                 = av_bswap32(offset);
         avio_skip(s->pb, 28);
         codec                  = avio_rb32(s->pb);

         st->codecpar->channels = avio_rb32(s->pb);

         avio_skip(s->pb, 4);
         st->duration           = avio_rb32(s->pb);
         avio_skip(s->pb, 8);

         st->codecpar->sample_rate = avio_rb32(s->pb);

     } else {
         avio_skip(s->pb, 28);
         codec                  = avio_rl32(s->pb);

         st->codecpar->channels = avio_rl32(s->pb);

         avio_skip(s->pb, 4);
         st->duration           = avio_rl32(s->pb);
         avio_skip(s->pb, 8);

         st->codecpar->sample_rate = avio_rl32(s->pb);

     }
 

     if (st->codecpar->sample_rate <= 0)

         return AVERROR_INVALIDDATA;

     if (st->codecpar->channels <= 0 || st->codecpar->channels > FF_SANE_NB_CHANNELS)

         return AVERROR_INVALIDDATA;
 
     switch (codec) {
     case 0x1c:

         st->codecpar->codec_id    = AV_CODEC_ID_ADPCM_PSX;
         st->codecpar->block_align = 16 * st->codecpar->channels;

         break;
     default:
         avpriv_request_sample(s, "codec %X", codec);
         return AVERROR_PATCHWELCOME;
     };
 
     avio_skip(s->pb, offset - avio_tell(s->pb));
 
     if (avio_rb16(s->pb) == 0xFFFB) {

         st->codecpar->codec_id    = AV_CODEC_ID_MP3;
         st->codecpar->block_align = 0x1000;

         st->need_parsing       = AVSTREAM_PARSE_FULL_RAW;
     }
 
     avio_skip(s->pb, -2);

     avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);

 
     return 0;
 }
 
 static int xvag_read_packet(AVFormatContext *s, AVPacket *pkt)
 {

     AVCodecParameters *par = s->streams[0]->codecpar;

     return av_get_packet(s->pb, pkt, par->block_align);

 }
 
 AVInputFormat ff_xvag_demuxer = {
     .name           = "xvag",
     .long_name      = NULL_IF_CONFIG_SMALL("Sony PS3 XVAG"),
     .read_probe     = xvag_probe,
     .read_header    = xvag_read_header,
     .read_packet    = xvag_read_packet,
     .extensions     = "xvag",
 };