/*

  * Sierra SOL demuxer

  * Copyright Konstantin Shishkov

  *

  * 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

  */
 

 /*

  * Based on documents from Game Audio Player and own research
  */
 

 #include "libavutil/channel_layout.h"

 #include "libavutil/intreadwrite.h"

 #include "avformat.h"

 #include "internal.h"

 #include "pcm.h"

 
 /* if we don't know the size in advance */

 #define AU_UNKNOWN_SIZE ((uint32_t)(~0))

 
 static int sol_probe(AVProbeData *p)
 {
     /* check file header */

     uint16_t magic = AV_RL32(p->buf);

     if ((magic == 0x0B8D || magic == 0x0C0D || magic == 0x0C8D) &&
         p->buf[2] == 'S' && p->buf[3] == 'O' &&
         p->buf[4] == 'L' && p->buf[5] == 0)
         return AVPROBE_SCORE_MAX;
     else
         return 0;
 }
 
 #define SOL_DPCM    1
 #define SOL_16BIT   4
 #define SOL_STEREO 16
 

 static enum AVCodecID sol_codec_id(int magic, int type)

 {
     if (magic == 0x0B8D)
     {

         if (type & SOL_DPCM) return AV_CODEC_ID_SOL_DPCM;
         else return AV_CODEC_ID_PCM_U8;

     }
     if (type & SOL_DPCM)
     {

         if (type & SOL_16BIT) return AV_CODEC_ID_SOL_DPCM;
         else if (magic == 0x0C8D) return AV_CODEC_ID_SOL_DPCM;
         else return AV_CODEC_ID_SOL_DPCM;

     }

     if (type & SOL_16BIT) return AV_CODEC_ID_PCM_S16LE;
     return AV_CODEC_ID_PCM_U8;

 }
 
 static int sol_codec_type(int magic, int type)
 {
     if (magic == 0x0B8D) return 1;//SOL_DPCM_OLD;
     if (type & SOL_DPCM)
     {
         if (type & SOL_16BIT) return 3;//SOL_DPCM_NEW16;
         else if (magic == 0x0C8D) return 1;//SOL_DPCM_OLD;
         else return 2;//SOL_DPCM_NEW8;
     }
     return -1;
 }
 
 static int sol_channels(int magic, int type)
 {
     if (magic == 0x0B8D || !(type & SOL_STEREO)) return 1;
     return 2;
 }

 static int sol_read_header(AVFormatContext *s)

 {
     unsigned int magic,tag;

     AVIOContext *pb = s->pb;

     unsigned int id, channels, rate, type;

     enum AVCodecID codec;

     AVStream *st;
 
     /* check ".snd" header */

     magic = avio_rl16(pb);
     tag = avio_rl32(pb);

     if (tag != MKTAG('S', 'O', 'L', 0))
         return -1;

     rate = avio_rl16(pb);
     type = avio_r8(pb);

     avio_skip(pb, 4); /* size */

     if (magic != 0x0B8D)

         avio_r8(pb); /* newer SOLs contain padding byte */

     codec = sol_codec_id(magic, type);
     channels = sol_channels(magic, type);

     if (codec == AV_CODEC_ID_SOL_DPCM)

         id = sol_codec_type(magic, type);
     else id = 0;

     /* now we are ready: build format streams */

     st = avformat_new_stream(s, NULL);

     if (!st)
         return -1;

     st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

     st->codec->codec_tag = id;
     st->codec->codec_id = codec;
     st->codec->channels = channels;

     st->codec->channel_layout = channels == 1 ? AV_CH_LAYOUT_MONO :
                                                 AV_CH_LAYOUT_STEREO;

     st->codec->sample_rate = rate;

     avpriv_set_pts_info(st, 64, 1, rate);

     return 0;
 }
 
 #define MAX_SIZE 4096
 
 static int sol_read_packet(AVFormatContext *s,
                           AVPacket *pkt)
 {
     int ret;
 

     if (url_feof(s->pb))

         return AVERROR(EIO);

     ret= av_get_packet(s->pb, pkt, MAX_SIZE);

     if (ret < 0)
         return ret;

     pkt->flags &= ~AV_PKT_FLAG_CORRUPT;

     pkt->stream_index = 0;
     return 0;
 }
 

 AVInputFormat ff_sol_demuxer = {

     .name           = "sol",

     .long_name      = NULL_IF_CONFIG_SMALL("Sierra SOL"),

     .read_probe     = sol_probe,
     .read_header    = sol_read_header,
     .read_packet    = sol_read_packet,

     .read_seek      = ff_pcm_read_seek,

 };