/*
  * Packed Animation File demuxer
  * Copyright (c) 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 "libavcodec/paf.h"
 #include "avformat.h"
 #include "internal.h"
 
 #define MAGIC "Packed Animation File V1.0\n(c) 1992-96 Amazing Studio\x0a\x1a"
 

 typedef struct PAFDemuxContext {

     uint32_t buffer_size;
     uint32_t frame_blks;
     uint32_t nb_frames;
     uint32_t start_offset;
     uint32_t preload_count;
     uint32_t max_video_blks;
     uint32_t max_audio_blks;
 
     uint32_t current_frame;
     uint32_t current_frame_count;
     uint32_t current_frame_block;
 
     uint32_t *blocks_count_table;
     uint32_t *frames_offset_table;
     uint32_t *blocks_offset_table;
 
     uint8_t  *video_frame;

     int video_size;

 
     uint8_t  *audio_frame;
     uint8_t  *temp_audio_frame;

     int audio_size;

     int got_audio;

 } PAFDemuxContext;
 
 static int read_probe(AVProbeData *p)
 {
     if ((p->buf_size >= strlen(MAGIC)) &&
         !memcmp(p->buf, MAGIC, strlen(MAGIC)))
         return AVPROBE_SCORE_MAX;
     return 0;
 }
 
 static int read_close(AVFormatContext *s)
 {
     PAFDemuxContext *p = s->priv_data;
 
     av_freep(&p->blocks_count_table);
     av_freep(&p->frames_offset_table);
     av_freep(&p->blocks_offset_table);
     av_freep(&p->video_frame);
     av_freep(&p->audio_frame);
     av_freep(&p->temp_audio_frame);
 
     return 0;
 }
 
 static void read_table(AVFormatContext *s, uint32_t *table, uint32_t count)
 {
     int i;
 
     for (i = 0; i < count; i++)
         table[i] = avio_rl32(s->pb);
 
     avio_skip(s->pb, 4 * (FFALIGN(count, 512) - count));
 }
 
 static int read_header(AVFormatContext *s)
 {

     PAFDemuxContext *p  = s->priv_data;

     AVIOContext     *pb = s->pb;
     AVStream        *ast, *vst;

     int ret = 0;

 
     avio_skip(pb, 132);
 
     vst = avformat_new_stream(s, 0);
     if (!vst)
         return AVERROR(ENOMEM);
 
     vst->start_time = 0;
     vst->nb_frames  =
     vst->duration   =

     p->nb_frames    = avio_rl32(pb);

     avio_skip(pb, 4);

     vst->codec->width  = avio_rl32(pb);
     vst->codec->height = avio_rl32(pb);
     avio_skip(pb, 4);

     vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
     vst->codec->codec_tag  = 0;

     vst->codec->codec_id   = AV_CODEC_ID_PAF_VIDEO;

     avpriv_set_pts_info(vst, 64, 1, 10);
 
     ast = avformat_new_stream(s, 0);
     if (!ast)
         return AVERROR(ENOMEM);
 

     ast->start_time            = 0;
     ast->codec->codec_type     = AVMEDIA_TYPE_AUDIO;
     ast->codec->codec_tag      = 0;
     ast->codec->codec_id       = AV_CODEC_ID_PAF_AUDIO;
     ast->codec->channels       = 2;

     ast->codec->channel_layout = AV_CH_LAYOUT_STEREO;

     ast->codec->sample_rate    = 22050;

     avpriv_set_pts_info(ast, 64, 1, 22050);
 
     p->buffer_size    = avio_rl32(pb);
     p->preload_count  = avio_rl32(pb);
     p->frame_blks     = avio_rl32(pb);
     p->start_offset   = avio_rl32(pb);
     p->max_video_blks = avio_rl32(pb);
     p->max_audio_blks = avio_rl32(pb);
     if (p->buffer_size    < 175  ||
         p->max_audio_blks < 2    ||
         p->max_video_blks < 1    ||
         p->frame_blks     < 1    ||
         p->nb_frames      < 1    ||
         p->preload_count  < 1    ||
         p->buffer_size    > 2048 ||
         p->max_video_blks > 2048 ||
         p->max_audio_blks > 2048 ||
         p->nb_frames      > INT_MAX / sizeof(uint32_t) ||
         p->frame_blks     > INT_MAX / sizeof(uint32_t))
         return AVERROR_INVALIDDATA;
 

     p->blocks_count_table  = av_mallocz(p->nb_frames *
                                         sizeof(*p->blocks_count_table));
     p->frames_offset_table = av_mallocz(p->nb_frames *
                                         sizeof(*p->frames_offset_table));
     p->blocks_offset_table = av_mallocz(p->frame_blks *
                                         sizeof(*p->blocks_offset_table));

     p->video_size  = p->max_video_blks * p->buffer_size;
     p->video_frame = av_mallocz(p->video_size);

     p->audio_size       = p->max_audio_blks * p->buffer_size;
     p->audio_frame      = av_mallocz(p->audio_size);
     p->temp_audio_frame = av_mallocz(p->audio_size);

 
     if (!p->blocks_count_table  ||
         !p->frames_offset_table ||
         !p->blocks_offset_table ||
         !p->video_frame         ||
         !p->audio_frame         ||
         !p->temp_audio_frame) {
         ret = AVERROR(ENOMEM);
         goto fail;
     }
 
     avio_seek(pb, p->buffer_size, SEEK_SET);
 
     read_table(s, p->blocks_count_table,  p->nb_frames);
     read_table(s, p->frames_offset_table, p->nb_frames);
     read_table(s, p->blocks_offset_table, p->frame_blks);
 
     p->got_audio = 0;
     p->current_frame = 0;
     p->current_frame_block = 0;
 
     avio_seek(pb, p->start_offset, SEEK_SET);
 
     return 0;
 
 fail:
     read_close(s);
 
     return ret;
 }
 
 static int read_packet(AVFormatContext *s, AVPacket *pkt)
 {

     PAFDemuxContext *p  = s->priv_data;

     AVIOContext     *pb = s->pb;
     uint32_t        count, offset;
     int             size, i;
 
     if (p->current_frame >= p->nb_frames)
         return AVERROR_EOF;
 

     if (avio_feof(pb))

         return AVERROR_EOF;
 
     if (p->got_audio) {
         if (av_new_packet(pkt, p->audio_size) < 0)
             return AVERROR(ENOMEM);
 
         memcpy(pkt->data, p->temp_audio_frame, p->audio_size);

         pkt->duration     = PAF_SOUND_SAMPLES * (p->audio_size / PAF_SOUND_FRAME_SIZE);

         pkt->flags       |= AV_PKT_FLAG_KEY;
         pkt->stream_index = 1;
         p->got_audio      = 0;
         return pkt->size;
     }
 

     count = (p->current_frame == 0) ? p->preload_count
                                     : p->blocks_count_table[p->current_frame - 1];

     for (i = 0; i < count; i++) {
         if (p->current_frame_block >= p->frame_blks)
             return AVERROR_INVALIDDATA;
 

         offset = p->blocks_offset_table[p->current_frame_block] & ~(1U << 31);
         if (p->blocks_offset_table[p->current_frame_block] & (1U << 31)) {

             if (offset > p->audio_size - p->buffer_size)
                 return AVERROR_INVALIDDATA;
 
             avio_read(pb, p->audio_frame + offset, p->buffer_size);
             if (offset == (p->max_audio_blks - 2) * p->buffer_size) {
                 memcpy(p->temp_audio_frame, p->audio_frame, p->audio_size);
                 p->got_audio = 1;
             }
         } else {
             if (offset > p->video_size - p->buffer_size)
                 return AVERROR_INVALIDDATA;
 
             avio_read(pb, p->video_frame + offset, p->buffer_size);
         }
         p->current_frame_block++;
     }
 

     if (p->frames_offset_table[p->current_frame] >= p->video_size)

         return AVERROR_INVALIDDATA;
 

     size = p->video_size - p->frames_offset_table[p->current_frame];
 

     if (av_new_packet(pkt, size) < 0)
         return AVERROR(ENOMEM);
 
     pkt->stream_index = 0;
     pkt->duration     = 1;
     memcpy(pkt->data, p->video_frame + p->frames_offset_table[p->current_frame], size);

     if (pkt->data[0] & 0x20)

         pkt->flags |= AV_PKT_FLAG_KEY;

     p->current_frame++;
 
     return pkt->size;
 }
 
 AVInputFormat ff_paf_demuxer = {
     .name           = "paf",
     .long_name      = NULL_IF_CONFIG_SMALL("Amazing Studio Packed Animation File"),
     .priv_data_size = sizeof(PAFDemuxContext),
     .read_probe     = read_probe,
     .read_header    = read_header,
     .read_packet    = read_packet,
     .read_close     = read_close,
 };