/*
  * CDXL demuxer
  * Copyright (c) 2011-2012 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/channel_layout.h"

 #include "libavutil/intreadwrite.h"
 #include "libavutil/parseutils.h"
 #include "libavutil/opt.h"
 #include "avformat.h"
 #include "internal.h"
 
 #define CDXL_HEADER_SIZE 32
 
 typedef struct CDXLDemuxContext {
     AVClass     *class;
     int         sample_rate;
     char        *framerate;
     AVRational  fps;
     int         read_chunk;
     uint8_t     header[CDXL_HEADER_SIZE];
     int         video_stream_index;
     int         audio_stream_index;

     int64_t     filesize;

 } CDXLDemuxContext;
 

 static int cdxl_read_probe(AVProbeData *p)
 {

     int score = AVPROBE_SCORE_EXTENSION + 10;

 
     if (p->buf_size < CDXL_HEADER_SIZE)
         return 0;
 
     /* reserved bytes should always be set to 0 */
     if (AV_RN64(&p->buf[24]) || AV_RN16(&p->buf[10]))
         return 0;
 
     /* check type */
     if (p->buf[0] != 1)
         return 0;
 
     /* check palette size */
     if (AV_RB16(&p->buf[20]) > 512)
         return 0;
 
     /* check number of planes */
     if (p->buf[18] || !p->buf[19])
         return 0;
 
     /* check widh and height */
     if (!AV_RN16(&p->buf[14]) || !AV_RN16(&p->buf[16]))
         return 0;
 
     /* chunk size */
     if (AV_RB32(&p->buf[2]) < AV_RB16(&p->buf[22]) + AV_RB16(&p->buf[20]) + CDXL_HEADER_SIZE)
         return 0;
 
     /* previous chunk size */
     if (AV_RN32(&p->buf[6]))
         score /= 2;
 
     /* current frame number, usually starts from 1 */
     if (AV_RB16(&p->buf[12]) != 1)
         score /= 2;
 
     return score;
 }
 

 static int cdxl_read_header(AVFormatContext *s)
 {
     CDXLDemuxContext *cdxl = s->priv_data;
     int ret;
 

     if (cdxl->framerate && (ret = av_parse_video_rate(&cdxl->fps, cdxl->framerate)) < 0) {

         av_log(s, AV_LOG_ERROR,
                "Could not parse framerate: %s.\n", cdxl->framerate);
         return ret;
     }
 
     cdxl->read_chunk         =  0;
     cdxl->video_stream_index = -1;
     cdxl->audio_stream_index = -1;
 

     cdxl->filesize = avio_size(s->pb);
 

     s->ctx_flags |= AVFMTCTX_NOHEADER;
 
     return 0;
 }
 
 static int cdxl_read_packet(AVFormatContext *s, AVPacket *pkt)
 {
     CDXLDemuxContext *cdxl = s->priv_data;
     AVIOContext *pb = s->pb;

     uint32_t current_size, video_size, image_size;
     uint16_t audio_size, palette_size, width, height;

     int64_t  pos;

     int      frames, ret;

     if (avio_feof(pb))

         return AVERROR_EOF;
 
     pos = avio_tell(pb);
     if (!cdxl->read_chunk &&
         avio_read(pb, cdxl->header, CDXL_HEADER_SIZE) != CDXL_HEADER_SIZE)
         return AVERROR_EOF;
     if (cdxl->header[0] != 1) {
         av_log(s, AV_LOG_ERROR, "non-standard cdxl file\n");
         return AVERROR_INVALIDDATA;
     }
 
     current_size = AV_RB32(&cdxl->header[2]);

     width        = AV_RB16(&cdxl->header[14]);
     height       = AV_RB16(&cdxl->header[16]);

     palette_size = AV_RB16(&cdxl->header[20]);
     audio_size   = AV_RB16(&cdxl->header[22]);

     if (FFALIGN(width, 16) * (uint64_t)height * cdxl->header[19] > INT_MAX)
         return AVERROR_INVALIDDATA;

     image_size   = FFALIGN(width, 16) * height * cdxl->header[19] / 8;
     video_size   = palette_size + image_size;

 
     if (palette_size > 512)
         return AVERROR_INVALIDDATA;

     if (current_size < (uint64_t)audio_size + video_size + CDXL_HEADER_SIZE)

         return AVERROR_INVALIDDATA;
 
     if (cdxl->read_chunk && audio_size) {
         if (cdxl->audio_stream_index == -1) {
             AVStream *st = avformat_new_stream(s, NULL);
             if (!st)
                 return AVERROR(ENOMEM);
 
             st->codec->codec_type    = AVMEDIA_TYPE_AUDIO;
             st->codec->codec_tag     = 0;

             st->codec->codec_id      = AV_CODEC_ID_PCM_S8;

             if (cdxl->header[1] & 0x10) {
                 st->codec->channels       = 2;
                 st->codec->channel_layout = AV_CH_LAYOUT_STEREO;
             } else {
                 st->codec->channels       = 1;
                 st->codec->channel_layout = AV_CH_LAYOUT_MONO;
             }

             st->codec->sample_rate   = cdxl->sample_rate;

             st->start_time           = 0;

             cdxl->audio_stream_index = st->index;

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

         }
 
         ret = av_get_packet(pb, pkt, audio_size);
         if (ret < 0)
             return ret;
         pkt->stream_index = cdxl->audio_stream_index;
         pkt->pos          = pos;
         pkt->duration     = audio_size;
         cdxl->read_chunk  = 0;
     } else {
         if (cdxl->video_stream_index == -1) {
             AVStream *st = avformat_new_stream(s, NULL);
             if (!st)
                 return AVERROR(ENOMEM);
 
             st->codec->codec_type    = AVMEDIA_TYPE_VIDEO;
             st->codec->codec_tag     = 0;

             st->codec->codec_id      = AV_CODEC_ID_CDXL;

             st->codec->width         = width;
             st->codec->height        = height;

 
             if (audio_size + video_size && cdxl->filesize > 0) {
                 frames = cdxl->filesize / (audio_size + video_size);
 
                 if(cdxl->framerate)
                     st->duration = frames;
                 else

                     st->duration = frames * (int64_t)audio_size;

             }

             st->start_time           = 0;

             cdxl->video_stream_index = st->index;

             if (cdxl->framerate)
                 avpriv_set_pts_info(st, 64, cdxl->fps.den, cdxl->fps.num);
             else
                 avpriv_set_pts_info(st, 64, 1, cdxl->sample_rate);

         }
 
         if (av_new_packet(pkt, video_size + CDXL_HEADER_SIZE) < 0)
             return AVERROR(ENOMEM);
         memcpy(pkt->data, cdxl->header, CDXL_HEADER_SIZE);
         ret = avio_read(pb, pkt->data + CDXL_HEADER_SIZE, video_size);
         if (ret < 0) {

             av_packet_unref(pkt);

             return ret;
         }

         av_shrink_packet(pkt, CDXL_HEADER_SIZE + ret);

         pkt->stream_index  = cdxl->video_stream_index;
         pkt->flags        |= AV_PKT_FLAG_KEY;
         pkt->pos           = pos;

         pkt->duration      = cdxl->framerate ? 1 : audio_size ? audio_size : 220;

         cdxl->read_chunk   = audio_size;
     }
 

     if (!cdxl->read_chunk)
         avio_skip(pb, current_size - audio_size - video_size - CDXL_HEADER_SIZE);

     return ret;
 }
 
 #define OFFSET(x) offsetof(CDXLDemuxContext, x)
 static const AVOption cdxl_options[] = {

     { "sample_rate", "", OFFSET(sample_rate), AV_OPT_TYPE_INT,    { .i64 = 11025 }, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },

     { "framerate",   "", OFFSET(framerate),   AV_OPT_TYPE_STRING, { .str = NULL },  0, 0,       AV_OPT_FLAG_DECODING_PARAM },

     { NULL },
 };
 
 static const AVClass cdxl_demuxer_class = {
     .class_name = "CDXL demuxer",
     .item_name  = av_default_item_name,
     .option     = cdxl_options,
     .version    = LIBAVUTIL_VERSION_INT,
 };
 
 AVInputFormat ff_cdxl_demuxer = {
     .name           = "cdxl",

     .long_name      = NULL_IF_CONFIG_SMALL("Commodore CDXL video"),

     .priv_data_size = sizeof(CDXLDemuxContext),

     .read_probe     = cdxl_read_probe,

     .read_header    = cdxl_read_header,
     .read_packet    = cdxl_read_packet,
     .extensions     = "cdxl,xl",
     .flags          = AVFMT_GENERIC_INDEX,
     .priv_class     = &cdxl_demuxer_class,
 };