/*
  * Sierra VMD Format Demuxer
  * Copyright (c) 2004 The ffmpeg Project
  *

  * 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

  */
 
 /**

  * @file

  * Sierra VMD file demuxer
  * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)

  * for more information on the Sierra VMD file format, visit:
  *   http://www.pcisys.net/~melanson/codecs/

  */
 

 #include "libavutil/channel_layout.h"

 #include "libavutil/intreadwrite.h"

 #include "avformat.h"

 #include "internal.h"

 #include "avio_internal.h"

 
 #define VMD_HEADER_SIZE 0x0330
 #define BYTES_PER_FRAME_RECORD 16
 
 typedef struct {
   int stream_index;

   int64_t frame_offset;

   unsigned int frame_size;
   int64_t pts;
   int keyframe;
   unsigned char frame_record[BYTES_PER_FRAME_RECORD];

 } vmd_frame;

 
 typedef struct VmdDemuxContext {
     int video_stream_index;
     int audio_stream_index;
 
     unsigned int frame_count;

     unsigned int frames_per_block;

     vmd_frame *frame_table;

     unsigned int current_frame;

     int is_indeo3;

     int sample_rate;
     int64_t audio_sample_counter;

     int skiphdr;

     unsigned char vmd_header[VMD_HEADER_SIZE];
 } VmdDemuxContext;
 
 static int vmd_probe(AVProbeData *p)
 {

     int w, h, sample_rate;
     if (p->buf_size < 806)

         return 0;

     /* check if the first 2 bytes of the file contain the appropriate size
      * of a VMD header chunk */

     if (AV_RL16(&p->buf[0]) != VMD_HEADER_SIZE - 2)

         return 0;

     w = AV_RL16(&p->buf[12]);
     h = AV_RL16(&p->buf[14]);

     sample_rate = AV_RL16(&p->buf[804]);
     if ((!w || w > 2048 || !h || h > 2048) &&
         sample_rate != 22050)

         return 0;

 
     /* only return half certainty since this check is a bit sketchy */

     return AVPROBE_SCORE_EXTENSION;

 }
 

 static int vmd_read_header(AVFormatContext *s)

 {

     VmdDemuxContext *vmd = s->priv_data;

     AVIOContext *pb = s->pb;

     AVStream *st = NULL, *vst = NULL;

     unsigned int toc_offset;
     unsigned char *raw_frame_table;
     int raw_frame_table_size;

     int64_t current_offset;

     int i, j, ret;

     int width, height;

     unsigned int total_frames;

     int64_t current_audio_pts = 0;

     unsigned char chunk[BYTES_PER_FRAME_RECORD];

     int num, den;

     int sound_buffers;

 
     /* fetch the main header, including the 2 header length bytes */

     avio_seek(pb, 0, SEEK_SET);

     if (avio_read(pb, vmd->vmd_header, VMD_HEADER_SIZE) != VMD_HEADER_SIZE)

         return AVERROR(EIO);

     width = AV_RL16(&vmd->vmd_header[12]);
     height = AV_RL16(&vmd->vmd_header[14]);
     if (width && height) {

         if(vmd->vmd_header[24] == 'i' && vmd->vmd_header[25] == 'v' && vmd->vmd_header[26] == '3') {
             vmd->is_indeo3 = 1;
         } else {
             vmd->is_indeo3 = 0;
         }
         /* start up the decoders */
         vst = avformat_new_stream(s, NULL);
         if (!vst)
             return AVERROR(ENOMEM);
         avpriv_set_pts_info(vst, 33, 1, 10);
         vmd->video_stream_index = vst->index;
         vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
         vst->codec->codec_id = vmd->is_indeo3 ? AV_CODEC_ID_INDEO3 : AV_CODEC_ID_VMDVIDEO;
         vst->codec->codec_tag = 0;  /* no fourcc */
         vst->codec->width = width;
         vst->codec->height = height;
         if(vmd->is_indeo3 && vst->codec->width > 320){
             vst->codec->width >>= 1;
             vst->codec->height >>= 1;
         }

         if (ff_alloc_extradata(vst->codec, VMD_HEADER_SIZE))

             return AVERROR(ENOMEM);

         memcpy(vst->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);

     }

 
     /* if sample rate is 0, assume no audio */

     vmd->sample_rate = AV_RL16(&vmd->vmd_header[804]);

     if (vmd->sample_rate) {

         st = avformat_new_stream(s, NULL);

         if (!st)

             return AVERROR(ENOMEM);

         vmd->audio_stream_index = st->index;

         st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

         st->codec->codec_id = AV_CODEC_ID_VMDAUDIO;

         st->codec->codec_tag = 0;  /* no fourcc */

         if (vmd->vmd_header[811] & 0x80) {
             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 = vmd->sample_rate;

         st->codec->block_align = AV_RL16(&vmd->vmd_header[806]);

         if (st->codec->block_align & 0x8000) {

             st->codec->bits_per_coded_sample = 16;

             st->codec->block_align = -(st->codec->block_align - 0x10000);

         } else {

             st->codec->bits_per_coded_sample = 8;

         }

         st->codec->bit_rate = st->codec->sample_rate *

             st->codec->bits_per_coded_sample * st->codec->channels;

         /* calculate pts */
         num = st->codec->block_align;
         den = st->codec->sample_rate * st->codec->channels;

         av_reduce(&num, &den, num, den, (1UL<<31)-1);

         if (vst)

             avpriv_set_pts_info(vst, 33, num, den);

         avpriv_set_pts_info(st, 33, num, den);

     }
 

     toc_offset = AV_RL32(&vmd->vmd_header[812]);
     vmd->frame_count = AV_RL16(&vmd->vmd_header[6]);
     vmd->frames_per_block = AV_RL16(&vmd->vmd_header[18]);

     avio_seek(pb, toc_offset, SEEK_SET);

 
     raw_frame_table = NULL;
     vmd->frame_table = NULL;

     sound_buffers = AV_RL16(&vmd->vmd_header[808]);

     raw_frame_table_size = vmd->frame_count * 6;

     if(vmd->frame_count * vmd->frames_per_block >= UINT_MAX / sizeof(vmd_frame) - sound_buffers){

         av_log(s, AV_LOG_ERROR, "vmd->frame_count * vmd->frames_per_block too large\n");
         return -1;
     }

     raw_frame_table = av_malloc(raw_frame_table_size);

     vmd->frame_table = av_malloc((vmd->frame_count * vmd->frames_per_block + sound_buffers) * sizeof(vmd_frame));

     if (!raw_frame_table || !vmd->frame_table) {

         ret = AVERROR(ENOMEM);
         goto error;

     }

     if (avio_read(pb, raw_frame_table, raw_frame_table_size) !=

         raw_frame_table_size) {

         ret = AVERROR(EIO);
         goto error;

     }
 

     total_frames = 0;
     for (i = 0; i < vmd->frame_count; i++) {
 

         current_offset = AV_RL32(&raw_frame_table[6 * i + 2]);

 
         /* handle each entry in index block */
         for (j = 0; j < vmd->frames_per_block; j++) {
             int type;
             uint32_t size;
 

             if ((ret = avio_read(pb, chunk, BYTES_PER_FRAME_RECORD)) != BYTES_PER_FRAME_RECORD) {
                 av_log(s, AV_LOG_ERROR, "Failed to read frame record\n");
                 if (ret >= 0)
                     ret = AVERROR_INVALIDDATA;
                 goto error;
             }

             type = chunk[0];

             size = AV_RL32(&chunk[2]);

             if (size > INT_MAX / 2) {
                 av_log(s, AV_LOG_ERROR, "Invalid frame size\n");
                 ret = AVERROR_INVALIDDATA;
                 goto error;
             }

             if(!size && type != 1)

                 continue;
             switch(type) {
             case 1: /* Audio Chunk */

                 if (!st) break;

                 /* first audio chunk contains several audio buffers */

                 vmd->frame_table[total_frames].frame_offset = current_offset;
                 vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;
                 vmd->frame_table[total_frames].frame_size = size;
                 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
                 vmd->frame_table[total_frames].pts = current_audio_pts;
                 total_frames++;

                 if(!current_audio_pts)

                     current_audio_pts += sound_buffers - 1;

                 else
                     current_audio_pts++;

                 break;
             case 2: /* Video Chunk */
                 vmd->frame_table[total_frames].frame_offset = current_offset;
                 vmd->frame_table[total_frames].stream_index = vmd->video_stream_index;

                 vmd->frame_table[total_frames].frame_size = size;

                 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);

                 vmd->frame_table[total_frames].pts = i;

                 total_frames++;
                 break;
             }
             current_offset += size;

         }
     }
 
     av_free(raw_frame_table);
 
     vmd->current_frame = 0;

     vmd->frame_count = total_frames;

 
     return 0;

 
 error:

     av_freep(&raw_frame_table);
     av_freep(&vmd->frame_table);

     return ret;

 }
 
 static int vmd_read_packet(AVFormatContext *s,
                            AVPacket *pkt)
 {

     VmdDemuxContext *vmd = s->priv_data;

     AVIOContext *pb = s->pb;

     int ret = 0;

     vmd_frame *frame;

 
     if (vmd->current_frame >= vmd->frame_count)

         return AVERROR_EOF;

 
     frame = &vmd->frame_table[vmd->current_frame];
     /* position the stream (will probably be there already) */

     avio_seek(pb, frame->frame_offset, SEEK_SET);

     if(ffio_limit(pb, frame->frame_size) != frame->frame_size)
         return AVERROR(EIO);

     if (av_new_packet(pkt, frame->frame_size + BYTES_PER_FRAME_RECORD))

         return AVERROR(ENOMEM);

     pkt->pos= avio_tell(pb);

     memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD);

     if(vmd->is_indeo3 && frame->frame_record[0] == 0x02)

         ret = avio_read(pb, pkt->data, frame->frame_size);

     else

         ret = avio_read(pb, pkt->data + BYTES_PER_FRAME_RECORD,

             frame->frame_size);

     if (ret != frame->frame_size) {
         av_free_packet(pkt);

         ret = AVERROR(EIO);

     }

     pkt->stream_index = frame->stream_index;

     pkt->pts = frame->pts;

     av_log(s, AV_LOG_DEBUG, " dispatching %s frame with %d bytes and pts %"PRId64"\n",

             (frame->frame_record[0] == 0x02) ? "video" : "audio",
             frame->frame_size + BYTES_PER_FRAME_RECORD,

             pkt->pts);

 
     vmd->current_frame++;
 
     return ret;
 }
 
 static int vmd_read_close(AVFormatContext *s)
 {

     VmdDemuxContext *vmd = s->priv_data;

     av_freep(&vmd->frame_table);

 
     return 0;
 }
 

 AVInputFormat ff_vmd_demuxer = {

     .name           = "vmd",

     .long_name      = NULL_IF_CONFIG_SMALL("Sierra VMD"),

     .priv_data_size = sizeof(VmdDemuxContext),
     .read_probe     = vmd_probe,
     .read_header    = vmd_read_header,
     .read_packet    = vmd_read_packet,
     .read_close     = vmd_read_close,

 };