/*
  * Cryo Interactive Entertainment HNM4 demuxer
  *
  * Copyright (c) 2012 David Kment
  *

  * 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 <inttypes.h>
 

 #include "libavutil/intreadwrite.h"
 #include "avformat.h"
 #include "internal.h"
 
 #define HNM4_TAG MKTAG('H', 'N', 'M', '4')
 
 #define HNM4_SAMPLE_RATE 22050
 #define HNM4_FRAME_FPS 24
 
 #define HNM4_CHUNK_ID_PL 19536
 #define HNM4_CHUNK_ID_IZ 23113
 #define HNM4_CHUNK_ID_IU 21833
 #define HNM4_CHUNK_ID_SD 17491
 
 typedef struct Hnm4DemuxContext {
     uint8_t version;
     uint16_t width;
     uint16_t height;
     uint32_t filesize;
     uint32_t frames;
     uint32_t taboffset;
     uint16_t bits;
     uint16_t channels;
     uint32_t framesize;
     uint32_t currentframe;
     int64_t pts;
     uint32_t superchunk_remaining;
     AVPacket vpkt;
 } Hnm4DemuxContext;
 
 static int hnm_probe(AVProbeData *p)
 {
     if (p->buf_size < 4)
         return 0;
 
     // check for HNM4 header.
     // currently only HNM v4/v4A is supported
     if (AV_RL32(&p->buf[0]) == HNM4_TAG)
         return AVPROBE_SCORE_MAX;
 
     return 0;
 }
 
 static int hnm_read_header(AVFormatContext *s)
 {
     Hnm4DemuxContext *hnm = s->priv_data;
     AVIOContext *pb = s->pb;
     AVStream *vst;
 
     /* default context members */
     hnm->pts = 0;
     av_init_packet(&hnm->vpkt);
     hnm->vpkt.data = NULL;
     hnm->vpkt.size = 0;
 
     hnm->superchunk_remaining = 0;
 
     avio_skip(pb, 8);
     hnm->width     = avio_rl16(pb);
     hnm->height    = avio_rl16(pb);
     hnm->filesize  = avio_rl32(pb);
     hnm->frames    = avio_rl32(pb);
     hnm->taboffset = avio_rl32(pb);
     hnm->bits      = avio_rl16(pb);
     hnm->channels  = avio_rl16(pb);
     hnm->framesize = avio_rl32(pb);
     avio_skip(pb, 32);
 
     hnm->currentframe = 0;
 

     if (hnm->width  < 256 || hnm->width  > 640 ||

         hnm->height < 150 || hnm->height > 480) {
         av_log(s, AV_LOG_ERROR,
                "invalid resolution: %ux%u\n", hnm->width, hnm->height);
         return AVERROR_INVALIDDATA;
     }
 
     // TODO: find a better way to detect HNM4A
     if (hnm->width == 640)
         hnm->version = 0x4a;
     else
         hnm->version = 0x40;
 
     if (!(vst = avformat_new_stream(s, NULL)))
         return AVERROR(ENOMEM);
 
     vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
     vst->codec->codec_id   = AV_CODEC_ID_HNM4_VIDEO;
     vst->codec->codec_tag  = 0;
     vst->codec->width      = hnm->width;
     vst->codec->height     = hnm->height;
     vst->codec->extradata  = av_mallocz(1);
 
     vst->codec->extradata_size = 1;
     memcpy(vst->codec->extradata, &hnm->version, 1);
 
     vst->start_time = 0;
 
     avpriv_set_pts_info(vst, 33, 1, HNM4_FRAME_FPS);
 
     return 0;
 }
 
 static int hnm_read_packet(AVFormatContext *s, AVPacket *pkt)
 {
     Hnm4DemuxContext *hnm = s->priv_data;
     AVIOContext *pb = s->pb;
     int ret = 0;
 
     uint32_t superchunk_size, chunk_size;
     uint16_t chunk_id;
 
     if (hnm->currentframe == hnm->frames || pb->eof_reached)
         return AVERROR_EOF;
 
     if (hnm->superchunk_remaining == 0) {
         /* parse next superchunk */
         superchunk_size = avio_rl24(pb);
         avio_skip(pb, 1);
 
         hnm->superchunk_remaining = superchunk_size - 4;
     }
 
     chunk_size = avio_rl24(pb);
     avio_skip(pb, 1);
     chunk_id = avio_rl16(pb);
     avio_skip(pb, 2);
 

     if (chunk_size > hnm->superchunk_remaining || !chunk_size) {

         av_log(s, AV_LOG_ERROR,
                "invalid chunk size: %"PRIu32", offset: %"PRId64"\n",
                chunk_size, avio_tell(pb));

         avio_skip(pb, hnm->superchunk_remaining - 8);
         hnm->superchunk_remaining = 0;
     }
 
     switch (chunk_id) {
     case HNM4_CHUNK_ID_PL:
     case HNM4_CHUNK_ID_IZ:
     case HNM4_CHUNK_ID_IU:
         avio_seek(pb, -8, SEEK_CUR);
         ret += av_get_packet(pb, pkt, chunk_size);
         hnm->superchunk_remaining -= chunk_size;
         if (chunk_id == HNM4_CHUNK_ID_IZ || chunk_id == HNM4_CHUNK_ID_IU)
             hnm->currentframe++;
         break;
 
     case HNM4_CHUNK_ID_SD:
         avio_skip(pb, chunk_size - 8);
         hnm->superchunk_remaining -= chunk_size;
         break;
 
     default:

         av_log(s, AV_LOG_WARNING, "unknown chunk found: %"PRIu16", offset: %"PRId64"\n",
                chunk_id, avio_tell(pb));

         avio_skip(pb, chunk_size - 8);
         hnm->superchunk_remaining -= chunk_size;
         break;
     }
 
     return ret;
 }
 
 static int hnm_read_close(AVFormatContext *s)
 {
     Hnm4DemuxContext *hnm = s->priv_data;
 
     if (hnm->vpkt.size > 0)

         av_packet_unref(&hnm->vpkt);

 
     return 0;
 }
 
 AVInputFormat ff_hnm_demuxer = {
     .name           = "hnm",
     .long_name      = NULL_IF_CONFIG_SMALL("Cryo HNM v4"),
     .priv_data_size = sizeof(Hnm4DemuxContext),
     .read_probe     = hnm_probe,
     .read_header    = hnm_read_header,
     .read_packet    = hnm_read_packet,
     .read_close     = hnm_read_close,
     .flags          = AVFMT_NO_BYTE_SEEK | AVFMT_NOGENSEARCH | AVFMT_NOBINSEARCH
 };