/*
  * AVS demuxer.
  * Copyright (c) 2006  Aurelien Jacobs <aurel@gnuage.org>
  *

  * 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 "voc.h"
 
 
 typedef struct avs_format {

     VocDecContext voc;

     AVStream *st_video;
     AVStream *st_audio;
     int width;
     int height;
     int bits_per_sample;
     int fps;
     int nb_frames;
     int remaining_frame_size;
     int remaining_audio_size;

 } AvsFormat;

 
 typedef enum avs_block_type {

     AVS_NONE      = 0x00,

     AVS_VIDEO     = 0x01,
     AVS_AUDIO     = 0x02,
     AVS_PALETTE   = 0x03,
     AVS_GAME_DATA = 0x04,

 } AvsBlockType;

 
 static int avs_probe(AVProbeData * p)
 {
     const uint8_t *d;
 
     d = p->buf;
     if (d[0] == 'w' && d[1] == 'W' && d[2] == 0x10 && d[3] == 0)
         return 50;
 
     return 0;
 }
 

 static int avs_read_header(AVFormatContext * s)

 {

     AvsFormat *avs = s->priv_data;

 
     s->ctx_flags |= AVFMTCTX_NOHEADER;
 

     avio_skip(s->pb, 4);

     avs->width = avio_rl16(s->pb);
     avs->height = avio_rl16(s->pb);
     avs->bits_per_sample = avio_rl16(s->pb);
     avs->fps = avio_rl16(s->pb);
     avs->nb_frames = avio_rl32(s->pb);

     avs->remaining_frame_size = 0;
     avs->remaining_audio_size = 0;
 
     avs->st_video = avs->st_audio = NULL;
 
     if (avs->width != 318 || avs->height != 198)
         av_log(s, AV_LOG_ERROR, "This avs pretend to be %dx%d "
                "when the avs format is supposed to be 318x198 only.\n",
                avs->width, avs->height);
 
     return 0;
 }
 
 static int
 avs_read_video_packet(AVFormatContext * s, AVPacket * pkt,

                       AvsBlockType type, int sub_type, int size,

                       uint8_t * palette, int palette_size)
 {

     AvsFormat *avs = s->priv_data;

     int ret;
 
     ret = av_new_packet(pkt, size + palette_size);
     if (ret < 0)
         return ret;
 
     if (palette_size) {
         pkt->data[0] = 0x00;
         pkt->data[1] = 0x03;
         pkt->data[2] = palette_size & 0xFF;
         pkt->data[3] = (palette_size >> 8) & 0xFF;
         memcpy(pkt->data + 4, palette, palette_size - 4);
     }
 
     pkt->data[palette_size + 0] = sub_type;
     pkt->data[palette_size + 1] = type;
     pkt->data[palette_size + 2] = size & 0xFF;
     pkt->data[palette_size + 3] = (size >> 8) & 0xFF;

     ret = avio_read(s->pb, pkt->data + palette_size + 4, size - 4) + 4;

     if (ret < size) {
         av_free_packet(pkt);

         return AVERROR(EIO);

     }
 
     pkt->size = ret + palette_size;
     pkt->stream_index = avs->st_video->index;
     if (sub_type == 0)

         pkt->flags |= AV_PKT_FLAG_KEY;

 
     return 0;
 }
 
 static int avs_read_audio_packet(AVFormatContext * s, AVPacket * pkt)
 {

     AvsFormat *avs = s->priv_data;

     int ret, size;
 

     size = avio_tell(s->pb);

     ret = ff_voc_get_packet(s, pkt, avs->st_audio, avs->remaining_audio_size);

     size = avio_tell(s->pb) - size;

     avs->remaining_audio_size -= size;
 

     if (ret == AVERROR(EIO))

         return 0;    /* this indicate EOS */
     if (ret < 0)
         return ret;
 
     pkt->stream_index = avs->st_audio->index;

     pkt->flags |= AV_PKT_FLAG_KEY;

 
     return size;
 }
 
 static int avs_read_packet(AVFormatContext * s, AVPacket * pkt)
 {

     AvsFormat *avs = s->priv_data;

     int sub_type = 0, size = 0;

     AvsBlockType type = AVS_NONE;

     int palette_size = 0;
     uint8_t palette[4 + 3 * 256];
     int ret;
 
     if (avs->remaining_audio_size > 0)
         if (avs_read_audio_packet(s, pkt) > 0)
             return 0;
 
     while (1) {
         if (avs->remaining_frame_size <= 0) {

             if (!avio_rl16(s->pb))    /* found EOF */

                 return AVERROR(EIO);

             avs->remaining_frame_size = avio_rl16(s->pb) - 4;

         }
 
         while (avs->remaining_frame_size > 0) {

             sub_type = avio_r8(s->pb);
             type = avio_r8(s->pb);
             size = avio_rl16(s->pb);

             if (size < 4)
                 return AVERROR_INVALIDDATA;

             avs->remaining_frame_size -= size;
 
             switch (type) {
             case AVS_PALETTE:

                 if (size - 4 > sizeof(palette))
                     return AVERROR_INVALIDDATA;

                 ret = avio_read(s->pb, palette, size - 4);

                 if (ret < size - 4)

                     return AVERROR(EIO);

                 palette_size = size;
                 break;
 
             case AVS_VIDEO:
                 if (!avs->st_video) {

                     avs->st_video = avformat_new_stream(s, NULL);

                     if (avs->st_video == NULL)

                         return AVERROR(ENOMEM);

                     avs->st_video->codec->codec_type = AVMEDIA_TYPE_VIDEO;

                     avs->st_video->codec->codec_id = AV_CODEC_ID_AVS;

                     avs->st_video->codec->width = avs->width;
                     avs->st_video->codec->height = avs->height;

                     avs->st_video->codec->bits_per_coded_sample=avs->bits_per_sample;

                     avs->st_video->nb_frames = avs->nb_frames;

 #if FF_API_R_FRAME_RATE
                     avs->st_video->r_frame_rate =
 #endif
                     avs->st_video->avg_frame_rate = (AVRational){avs->fps, 1};

                 }
                 return avs_read_video_packet(s, pkt, type, sub_type, size,
                                              palette, palette_size);
 
             case AVS_AUDIO:
                 if (!avs->st_audio) {

                     avs->st_audio = avformat_new_stream(s, NULL);

                     if (avs->st_audio == NULL)

                         return AVERROR(ENOMEM);

                     avs->st_audio->codec->codec_type = AVMEDIA_TYPE_AUDIO;

                 }
                 avs->remaining_audio_size = size - 4;
                 size = avs_read_audio_packet(s, pkt);
                 if (size != 0)
                     return size;
                 break;
 
             default:

                 avio_skip(s->pb, size - 4);

             }
         }
     }
 }
 
 static int avs_read_close(AVFormatContext * s)
 {
     return 0;
 }
 

 AVInputFormat ff_avs_demuxer = {

     .name           = "avs",

     .long_name      = NULL_IF_CONFIG_SMALL("AVS"),

     .priv_data_size = sizeof(AvsFormat),
     .read_probe     = avs_probe,
     .read_header    = avs_read_header,
     .read_packet    = avs_read_packet,
     .read_close     = avs_read_close,

 };