/*
  * SMJPEG demuxer
  * Copyright (c) 2011 Paul B Mahol
  *
  * This file is part of Libav.
  *
  * Libav 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.
  *
  * Libav 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 Libav; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 /**
  * @file
  * This is a demuxer for Loki SDL Motion JPEG files
  */
 
 #include "avformat.h"
 #include "internal.h"
 #include "riff.h"
 #include "smjpeg.h"
 
 typedef struct SMJPEGContext {
     int audio_stream_index;
     int video_stream_index;
 } SMJPEGContext;
 
 static int smjpeg_probe(AVProbeData *p)
 {
     if (!memcmp(p->buf, SMJPEG_MAGIC, 8))
         return AVPROBE_SCORE_MAX;
     return 0;
 }
 
 static int smjpeg_read_header(AVFormatContext *s, AVFormatParameters *ap)
 {
     SMJPEGContext *sc = s->priv_data;
     AVStream *ast = NULL, *vst = NULL;
     AVIOContext *pb = s->pb;
     uint32_t version, htype, hlength, duration;
     char *comment;
 
     avio_skip(pb, 8); // magic
     version = avio_rb32(pb);
     if (version)
         av_log_ask_for_sample(s, "unknown version %d\n", version);
 
     duration = avio_rb32(pb); // in msec
 
     while (!pb->eof_reached) {
         htype = avio_rl32(pb);
         switch (htype) {
         case SMJPEG_TXT:
             hlength = avio_rb32(pb);
             if (!hlength || hlength > 512)
                 return AVERROR_INVALIDDATA;
             comment = av_malloc(hlength + 1);
             if (!comment)
                 return AVERROR(ENOMEM);
             if (avio_read(pb, comment, hlength) != hlength) {
                 av_freep(&comment);
                 av_log(s, AV_LOG_ERROR, "error when reading comment\n");
                 return AVERROR_INVALIDDATA;
             }
             comment[hlength] = 0;
             av_dict_set(&s->metadata, "comment", comment,
                         AV_DICT_DONT_STRDUP_VAL);
             break;
         case SMJPEG_SND:
             if (ast) {
                 av_log_ask_for_sample(s, "multiple audio streams not supported\n");
                 return AVERROR_INVALIDDATA;
             }
             hlength = avio_rb32(pb);
             if (hlength < 8)
                 return AVERROR_INVALIDDATA;
             ast = avformat_new_stream(s, 0);
             if (!ast)
                 return AVERROR(ENOMEM);
             ast->codec->codec_type  = AVMEDIA_TYPE_AUDIO;
             ast->codec->sample_rate = avio_rb16(pb);
             ast->codec->bits_per_coded_sample = avio_r8(pb);
             ast->codec->channels    = avio_r8(pb);
             ast->codec->codec_tag   = avio_rl32(pb);
             ast->codec->codec_id    = ff_codec_get_id(ff_codec_smjpeg_audio_tags,
                                                       ast->codec->codec_tag);
             ast->duration           = duration;
             sc->audio_stream_index  = ast->index;
             avpriv_set_pts_info(ast, 32, 1, 1000);
             avio_skip(pb, hlength - 8);
             break;
         case SMJPEG_VID:
             if (vst) {
                 av_log_ask_for_sample(s, "multiple video streams not supported\n");
                 return AVERROR_INVALIDDATA;
             }
             hlength = avio_rb32(pb);
             if (hlength < 12)
                 return AVERROR_INVALIDDATA;
             avio_skip(pb, 4); // number of frames
             vst = avformat_new_stream(s, 0);
             if (!vst)
                 return AVERROR(ENOMEM);
             vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
             vst->codec->width      = avio_rb16(pb);
             vst->codec->height     = avio_rb16(pb);
             vst->codec->codec_tag  = avio_rl32(pb);
             vst->codec->codec_id   = ff_codec_get_id(ff_codec_smjpeg_video_tags,
                                                      vst->codec->codec_tag);
             vst->duration          = duration;
             sc->video_stream_index = vst->index;
             avpriv_set_pts_info(vst, 32, 1, 1000);
             avio_skip(pb, hlength - 12);
             break;
         case SMJPEG_HEND:
             return 0;
         default:
             av_log(s, AV_LOG_ERROR, "unknown header %x\n", htype);
             return AVERROR_INVALIDDATA;
         }
     }
 
     return AVERROR_EOF;
 }
 
 static int smjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
 {
     SMJPEGContext *sc = s->priv_data;
     uint32_t dtype, ret, size, timestamp;
 
     if (s->pb->eof_reached)
         return AVERROR_EOF;
     dtype = avio_rl32(s->pb);
     switch (dtype) {
     case SMJPEG_SNDD:
         timestamp = avio_rb32(s->pb);
         size = avio_rb32(s->pb);
         ret = av_get_packet(s->pb, pkt, size);
         pkt->stream_index = sc->audio_stream_index;
         pkt->pts = timestamp;
         break;
     case SMJPEG_VIDD:
         timestamp = avio_rb32(s->pb);
         size = avio_rb32(s->pb);
         ret = av_get_packet(s->pb, pkt, size);
         pkt->stream_index = sc->video_stream_index;
         pkt->pts = timestamp;
         break;
     case SMJPEG_DONE:
         ret = AVERROR_EOF;
         break;
     default:
         av_log(s, AV_LOG_ERROR, "unknown chunk %x\n", dtype);
         ret = AVERROR_INVALIDDATA;
         break;
     }
     return ret;
 }
 
 AVInputFormat ff_smjpeg_demuxer = {
     .name           = "smjpeg",
     .long_name      = NULL_IF_CONFIG_SMALL("Loki SDL MJPEG"),
     .priv_data_size = sizeof(SMJPEGContext),
     .read_probe     = smjpeg_probe,
     .read_header    = smjpeg_read_header,
     .read_packet    = smjpeg_read_packet,
     .extensions     = "mjpg",
 };