/*
  * NuppelVideo demuxer.

  * Copyright (c) 2006 Reimar Doeffinger

  *

  * 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/intreadwrite.h"

 #include "libavutil/intfloat.h"

 #include "avformat.h"

 #include "internal.h"

 #include "riff.h"

 
 typedef struct {
     int v_id;
     int a_id;

     int rtjpg_video;

 } NUVContext;
 
 typedef enum {
     NUV_VIDEO = 'V',
     NUV_EXTRADATA = 'D',
     NUV_AUDIO = 'A',
     NUV_SEEKP = 'R',
     NUV_MYTHEXT = 'X'

 } nuv_frametype;

 
 static int nuv_probe(AVProbeData *p) {
     if (!memcmp(p->buf, "NuppelVideo", 12))
         return AVPROBE_SCORE_MAX;
     if (!memcmp(p->buf, "MythTVVideo", 12))
         return AVPROBE_SCORE_MAX;
     return 0;
 }
 

 /// little macro to sanitize packet size

 #define PKTSIZE(s) (s &  0xffffff)
 
 /**

  * @brief read until we found all data needed for decoding
  * @param vst video stream of which to change parameters
  * @param ast video stream of which to change parameters
  * @param myth set if this is a MythTVVideo format file
  * @return 1 if all required codec data was found

  */

 static int get_codec_data(AVIOContext *pb, AVStream *vst,

                           AVStream *ast, int myth) {

     nuv_frametype frametype;

     if (!vst && !myth)
         return 1; // no codec data needed
     while (!url_feof(pb)) {
         int size, subtype;

         frametype = avio_r8(pb);

         switch (frametype) {
             case NUV_EXTRADATA:

                 subtype = avio_r8(pb);

                 avio_skip(pb, 6);

                 size = PKTSIZE(avio_rl32(pb));

                 if (vst && subtype == 'R') {

                     vst->codec->extradata_size = size;
                     vst->codec->extradata = av_malloc(size);

                     avio_read(pb, vst->codec->extradata, size);

                     size = 0;
                     if (!myth)
                         return 1;
                 }
                 break;
             case NUV_MYTHEXT:

                 avio_skip(pb, 7);

                 size = PKTSIZE(avio_rl32(pb));

                 if (size != 128 * 4)
                     break;

                 avio_rl32(pb); // version

                 if (vst) {

                     vst->codec->codec_tag = avio_rl32(pb);

                     vst->codec->codec_id =

                         ff_codec_get_id(ff_codec_bmp_tags, vst->codec->codec_tag);

                     if (vst->codec->codec_tag == MKTAG('R', 'J', 'P', 'G'))
                         vst->codec->codec_id = CODEC_ID_NUV;

                 } else

                     avio_skip(pb, 4);

 
                 if (ast) {

                     ast->codec->codec_tag = avio_rl32(pb);
                     ast->codec->sample_rate = avio_rl32(pb);
                     ast->codec->bits_per_coded_sample = avio_rl32(pb);
                     ast->codec->channels = avio_rl32(pb);

                     ast->codec->codec_id =

                         ff_wav_codec_get_id(ast->codec->codec_tag,

                                          ast->codec->bits_per_coded_sample);

                     ast->need_parsing = AVSTREAM_PARSE_FULL;

                 } else

                     avio_skip(pb, 4 * 4);

 
                 size -= 6 * 4;

                 avio_skip(pb, size);

                 return 1;
             case NUV_SEEKP:
                 size = 11;
                 break;
             default:

                 avio_skip(pb, 7);

                 size = PKTSIZE(avio_rl32(pb));

                 break;
         }

         avio_skip(pb, size);

     }
     return 0;
 }
 

 static int nuv_header(AVFormatContext *s) {

     NUVContext *ctx = s->priv_data;

     AVIOContext *pb = s->pb;

     char id_string[12];

     double aspect, fps;
     int is_mythtv, width, height, v_packs, a_packs;
     int stream_nr = 0;
     AVStream *vst = NULL, *ast = NULL;

     avio_read(pb, id_string, 12);

     is_mythtv = !memcmp(id_string, "MythTVVideo", 12);

     avio_skip(pb, 5); // version string
     avio_skip(pb, 3); // padding

     width = avio_rl32(pb);
     height = avio_rl32(pb);
     avio_rl32(pb); // unused, "desiredwidth"
     avio_rl32(pb); // unused, "desiredheight"
     avio_r8(pb); // 'P' == progressive, 'I' == interlaced

     avio_skip(pb, 3); // padding

     aspect = av_int2double(avio_rl64(pb));

     if (aspect > 0.9999 && aspect < 1.0001)
         aspect = 4.0 / 3.0;

     fps = av_int2double(avio_rl64(pb));

 
     // number of packets per stream type, -1 means unknown, e.g. streaming

     v_packs = avio_rl32(pb);
     a_packs = avio_rl32(pb);
     avio_rl32(pb); // text

     avio_rl32(pb); // keyframe distance (?)

 
     if (v_packs) {
         ctx->v_id = stream_nr++;

         vst = avformat_new_stream(s, NULL);

         if (!vst)
             return AVERROR(ENOMEM);

         vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;

         vst->codec->codec_id = CODEC_ID_NUV;
         vst->codec->width = width;
         vst->codec->height = height;

         vst->codec->bits_per_coded_sample = 10;

         vst->sample_aspect_ratio = av_d2q(aspect * height / width, 10000);

         vst->r_frame_rate = av_d2q(fps, 60000);

         avpriv_set_pts_info(vst, 32, 1, 1000);

     } else
         ctx->v_id = -1;
 
     if (a_packs) {
         ctx->a_id = stream_nr++;

         ast = avformat_new_stream(s, NULL);

         if (!ast)
             return AVERROR(ENOMEM);

         ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;

         ast->codec->codec_id = CODEC_ID_PCM_S16LE;
         ast->codec->channels = 2;
         ast->codec->sample_rate = 44100;
         ast->codec->bit_rate = 2 * 2 * 44100 * 8;
         ast->codec->block_align = 2 * 2;

         ast->codec->bits_per_coded_sample = 16;

         avpriv_set_pts_info(ast, 32, 1, 1000);

     } else
         ctx->a_id = -1;
 
     get_codec_data(pb, vst, ast, is_mythtv);

     ctx->rtjpg_video = vst && vst->codec->codec_id == CODEC_ID_NUV;

     return 0;
 }
 
 #define HDRSIZE 12
 
 static int nuv_packet(AVFormatContext *s, AVPacket *pkt) {

     NUVContext *ctx = s->priv_data;

     AVIOContext *pb = s->pb;

     uint8_t hdr[HDRSIZE];

     nuv_frametype frametype;

     int ret, size;
     while (!url_feof(pb)) {

         int copyhdrsize = ctx->rtjpg_video ? HDRSIZE : 0;

         uint64_t pos = avio_tell(pb);

         ret = avio_read(pb, hdr, HDRSIZE);

         if (ret < HDRSIZE)
             return ret < 0 ? ret : AVERROR(EIO);

         frametype = hdr[0];

         size = PKTSIZE(AV_RL32(&hdr[8]));

         switch (frametype) {
             case NUV_EXTRADATA:

                 if (!ctx->rtjpg_video) {

                     avio_skip(pb, size);

                     break;
                 }
             case NUV_VIDEO:

                 if (ctx->v_id < 0) {
                     av_log(s, AV_LOG_ERROR, "Video packet in file without video stream!\n");

                     avio_skip(pb, size);

                     break;
                 }

                 ret = av_new_packet(pkt, copyhdrsize + size);

                 if (ret < 0)
                     return ret;

                 pkt->pos = pos;

                 pkt->flags |= hdr[2] == 0 ? AV_PKT_FLAG_KEY : 0;

                 pkt->pts = AV_RL32(&hdr[4]);

                 pkt->stream_index = ctx->v_id;

                 memcpy(pkt->data, hdr, copyhdrsize);

                 ret = avio_read(pb, pkt->data + copyhdrsize, size);

                 if (ret < 0) {
                     av_free_packet(pkt);
                     return ret;
                 }

                 if (ret < size)
                     av_shrink_packet(pkt, copyhdrsize + ret);

                 return 0;

             case NUV_AUDIO:
                 if (ctx->a_id < 0) {
                     av_log(s, AV_LOG_ERROR, "Audio packet in file without audio stream!\n");

                     avio_skip(pb, size);

                     break;
                 }
                 ret = av_get_packet(pb, pkt, size);

                 pkt->flags |= AV_PKT_FLAG_KEY;

                 pkt->pos = pos;

                 pkt->pts = AV_RL32(&hdr[4]);

                 pkt->stream_index = ctx->a_id;

                 if (ret < 0) return ret;
                 return 0;

             case NUV_SEEKP:
                 // contains no data, size value is invalid
                 break;
             default:

                 avio_skip(pb, size);

                 break;
         }
     }

     return AVERROR(EIO);

 }
 

 /**
  * \brief looks for the string RTjjjjjjjjjj in the stream too resync reading
  * \return 1 if the syncword is found 0 otherwise.
  */
 static int nuv_resync(AVFormatContext *s, int64_t pos_limit) {
     AVIOContext *pb = s->pb;
     uint32_t tag = 0;
     while(!url_feof(pb) && avio_tell(pb) < pos_limit) {
         tag = (tag << 8) | avio_r8(pb);
         if (tag                  == MKBETAG('R','T','j','j') &&
            (tag = avio_rb32(pb)) == MKBETAG('j','j','j','j') &&
            (tag = avio_rb32(pb)) == MKBETAG('j','j','j','j'))
             return 1;
     }
     return 0;
 }
 
 /**
  * \brief attempts to read a timestamp from stream at the given stream position

  * \return timestamp if successful and AV_NOPTS_VALUE if failure

  */
 static int64_t nuv_read_dts(AVFormatContext *s, int stream_index,
                             int64_t *ppos, int64_t pos_limit)
 {
     NUVContext *ctx = s->priv_data;
     AVIOContext *pb = s->pb;
     uint8_t hdr[HDRSIZE];
     nuv_frametype frametype;
     int size, key, idx;
     int64_t pos, dts;
 
     if (avio_seek(pb, *ppos, SEEK_SET) < 0)
         return AV_NOPTS_VALUE;
 
     if (!nuv_resync(s, pos_limit))
         return AV_NOPTS_VALUE;
 
     while (!url_feof(pb) && avio_tell(pb) < pos_limit) {
         if (avio_read(pb, hdr, HDRSIZE) < HDRSIZE)
             return AV_NOPTS_VALUE;
         frametype = hdr[0];
         size = PKTSIZE(AV_RL32(&hdr[8]));
         switch (frametype) {
             case NUV_SEEKP:
                 break;
             case NUV_AUDIO:
             case NUV_VIDEO:
                 if (frametype == NUV_VIDEO) {
                     idx = ctx->v_id;
                     key = hdr[2] == 0;
                 } else {
                     idx = ctx->a_id;
                     key = 1;
                 }
                 if (stream_index == idx) {
 
                     pos = avio_tell(s->pb) - HDRSIZE;
                     dts = AV_RL32(&hdr[4]);
 
                     // TODO - add general support in av_gen_search, so it adds positions after reading timestamps
                     av_add_index_entry(s->streams[stream_index], pos, dts, size + HDRSIZE, 0,
                             key ? AVINDEX_KEYFRAME : 0);
 
                     *ppos = pos;
                     return dts;
                 }
             default:
                 avio_skip(pb, size);
                 break;
         }
     }
     return AV_NOPTS_VALUE;
 }
 
 

 AVInputFormat ff_nuv_demuxer = {

     .name           = "nuv",
     .long_name      = NULL_IF_CONFIG_SMALL("NuppelVideo format"),
     .priv_data_size = sizeof(NUVContext),
     .read_probe     = nuv_probe,
     .read_header    = nuv_header,
     .read_packet    = nuv_packet,

     .read_timestamp = nuv_read_dts,

     .flags          = AVFMT_GENERIC_INDEX,

 };