/*
  * 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/channel_layout.h"

 #include "libavutil/intreadwrite.h"

 #include "libavutil/intfloat.h"

 #include "avformat.h"

 #include "internal.h"

 #include "riff.h"

 static const AVCodecTag nuv_audio_tags[] = {
     { AV_CODEC_ID_PCM_S16LE, MKTAG('R', 'A', 'W', 'A') },
     { AV_CODEC_ID_MP3,       MKTAG('L', 'A', 'M', 'E') },
     { AV_CODEC_ID_NONE,      0 },
 };
 

 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 0 or AVERROR code

  */

 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') {

                 if (vst->codec->extradata) {
                     av_freep(&vst->codec->extradata);
                     vst->codec->extradata_size = 0;
                 }
                 vst->codec->extradata = av_malloc(size);
                 if (!vst->codec->extradata)
                     return AVERROR(ENOMEM);

                 vst->codec->extradata_size = size;
                 avio_read(pb, vst->codec->extradata, size);
                 size = 0;
                 if (!myth)

                     return 0;

             }
             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 = AV_CODEC_ID_NUV;
             } else
                 avio_skip(pb, 4);

             if (ast) {
                 int id;

                 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->channel_layout        = 0;

                 id = ff_wav_codec_get_id(ast->codec->codec_tag,
                                          ast->codec->bits_per_coded_sample);
                 if (id == AV_CODEC_ID_NONE) {
                     id = ff_codec_get_id(nuv_audio_tags, ast->codec->codec_tag);
                     if (id == AV_CODEC_ID_PCM_S16LE)
                         id = ff_get_pcm_codec_id(ast->codec->bits_per_coded_sample,
                                                  0, 0, ~1);
                 }
                 ast->codec->codec_id = id;

                 ast->need_parsing = AVSTREAM_PARSE_FULL;
             } else
                 avio_skip(pb, 4 * 4);

             size -= 6 * 4;
             avio_skip(pb, size);

             return 0;

         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, ret;

     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) {

         vst = avformat_new_stream(s, NULL);

         if (!vst)
             return AVERROR(ENOMEM);

         ctx->v_id = vst->index;
 

         vst->codec->codec_type            = AVMEDIA_TYPE_VIDEO;
         vst->codec->codec_id              = AV_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);

 #if FF_API_R_FRAME_RATE
         vst->r_frame_rate =
 #endif
         vst->avg_frame_rate = av_d2q(fps, 60000);

         avpriv_set_pts_info(vst, 32, 1, 1000);

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

         ast = avformat_new_stream(s, NULL);

         if (!ast)
             return AVERROR(ENOMEM);

         ctx->a_id = ast->index;
 

         ast->codec->codec_type            = AVMEDIA_TYPE_AUDIO;
         ast->codec->codec_id              = AV_CODEC_ID_PCM_S16LE;
         ast->codec->channels              = 2;
         ast->codec->channel_layout        = AV_CH_LAYOUT_STEREO;
         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;
 

     if ((ret = get_codec_data(pb, vst, ast, is_mythtv)) < 0)
         return ret;
 

     ctx->rtjpg_video = vst && vst->codec->codec_id == AV_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"),

     .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,

 };