/*
  * DC STR 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 "avformat.h"
 #include "internal.h"
 
 static int dcstr_probe(AVProbeData *p)
 {
     if (p->buf_size < 224 || memcmp(p->buf + 213, "Sega Stream", 11))
         return 0;
 
     return AVPROBE_SCORE_MAX;
 }
 
 static int dcstr_read_header(AVFormatContext *s)
 {
     unsigned codec, align;
     AVStream *st;
 
     st = avformat_new_stream(s, NULL);
     if (!st)
         return AVERROR(ENOMEM);
 
     st->codec->codec_type  = AVMEDIA_TYPE_AUDIO;
     st->codec->channels    = avio_rl32(s->pb);
     st->codec->sample_rate = avio_rl32(s->pb);
     codec                  = avio_rl32(s->pb);
     align                  = avio_rl32(s->pb);
     avio_skip(s->pb, 4);
     st->duration           = avio_rl32(s->pb);
     st->codec->channels   *= avio_rl32(s->pb);
     if (!align || align > INT_MAX / st->codec->channels)
         return AVERROR_INVALIDDATA;
     st->codec->block_align = align * st->codec->channels;
 
     switch (codec) {
     case  4: st->codec->codec_id = AV_CODEC_ID_ADPCM_AICA;       break;
     case 16: st->codec->codec_id = AV_CODEC_ID_PCM_S16LE_PLANAR; break;
     default: avpriv_request_sample(s, "codec %X", codec);
              return AVERROR_PATCHWELCOME;
     }
 
     avio_skip(s->pb, 0x800 - avio_tell(s->pb));
     avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
 
     return 0;
 }
 
 static int dcstr_read_packet(AVFormatContext *s, AVPacket *pkt)
 {
     AVCodecContext *codec = s->streams[0]->codec;
     return av_get_packet(s->pb, pkt, codec->block_align);
 }
 
 AVInputFormat ff_dcstr_demuxer = {
     .name           = "dcstr",
     .long_name      = NULL_IF_CONFIG_SMALL("Sega DC STR"),
     .read_probe     = dcstr_probe,
     .read_header    = dcstr_read_header,
     .read_packet    = dcstr_read_packet,
     .extensions     = "str",
     .flags          = AVFMT_GENERIC_INDEX | AVFMT_NO_BYTE_SEEK | AVFMT_NOBINSEARCH,
 };