/*

  * FLV muxer

  * Copyright (c) 2003 The FFmpeg Project

  *

  * 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 "avformat.h"

 #include "flv.h"

 #include "internal.h"

 #include "avc.h"

 #include "metadata.h"

 #include "libavutil/dict.h"

 #undef NDEBUG
 #include <assert.h>
 

 static const AVCodecTag flv_video_codec_ids[] = {

     {CODEC_ID_FLV1,    FLV_CODECID_H263  },
     {CODEC_ID_FLASHSV, FLV_CODECID_SCREEN},

     {CODEC_ID_FLASHSV2, FLV_CODECID_SCREEN2},

     {CODEC_ID_VP6F,    FLV_CODECID_VP6   },

     {CODEC_ID_VP6,     FLV_CODECID_VP6   },

     {CODEC_ID_H264,    FLV_CODECID_H264  },

     {CODEC_ID_NONE,    0}
 };
 

 static const AVCodecTag flv_audio_codec_ids[] = {

     {CODEC_ID_MP3,       FLV_CODECID_MP3    >> FLV_AUDIO_CODECID_OFFSET},

     {CODEC_ID_PCM_U8,    FLV_CODECID_PCM    >> FLV_AUDIO_CODECID_OFFSET},

     {CODEC_ID_PCM_S16BE, FLV_CODECID_PCM    >> FLV_AUDIO_CODECID_OFFSET},

     {CODEC_ID_PCM_S16LE, FLV_CODECID_PCM_LE >> FLV_AUDIO_CODECID_OFFSET},
     {CODEC_ID_ADPCM_SWF, FLV_CODECID_ADPCM  >> FLV_AUDIO_CODECID_OFFSET},

     {CODEC_ID_AAC,       FLV_CODECID_AAC    >> FLV_AUDIO_CODECID_OFFSET},

     {CODEC_ID_NELLYMOSER, FLV_CODECID_NELLYMOSER >> FLV_AUDIO_CODECID_OFFSET},

     {CODEC_ID_SPEEX,     FLV_CODECID_SPEEX  >> FLV_AUDIO_CODECID_OFFSET},

     {CODEC_ID_NONE,      0}
 };
 

 typedef struct FLVContext {

     int reserved;

     int64_t duration_offset;
     int64_t filesize_offset;

     int64_t duration;

     int delay; ///< first dts delay for AVC

     int64_t last_video_ts;

 } FLVContext;
 

 static int get_audio_flags(AVCodecContext *enc){

     int flags = (enc->bits_per_coded_sample == 16) ? FLV_SAMPLESSIZE_16BIT : FLV_SAMPLESSIZE_8BIT;

     if (enc->codec_id == CODEC_ID_AAC) // specs force these parameters
         return FLV_CODECID_AAC | FLV_SAMPLERATE_44100HZ | FLV_SAMPLESSIZE_16BIT | FLV_STEREO;

     else if (enc->codec_id == CODEC_ID_SPEEX) {
         if (enc->sample_rate != 16000) {
             av_log(enc, AV_LOG_ERROR, "flv only supports wideband (16kHz) Speex audio\n");
             return -1;
         }
         if (enc->channels != 1) {
             av_log(enc, AV_LOG_ERROR, "flv only supports mono Speex audio\n");
             return -1;
         }
         if (enc->frame_size / 320 > 8) {

             av_log(enc, AV_LOG_WARNING, "Warning: Speex stream has more than "
                                         "8 frames per packet. Adobe Flash "
                                         "Player cannot handle this!\n");

         }
         return FLV_CODECID_SPEEX | FLV_SAMPLERATE_11025HZ | FLV_SAMPLESSIZE_16BIT;
     } else {

     switch (enc->sample_rate) {
         case    44100:

             flags |= FLV_SAMPLERATE_44100HZ;

             break;
         case    22050:

             flags |= FLV_SAMPLERATE_22050HZ;

             break;
         case    11025:

             flags |= FLV_SAMPLERATE_11025HZ;

             break;
         case     8000: //nellymoser only
         case     5512: //not mp3

             if(enc->codec_id != CODEC_ID_MP3){

                 flags |= FLV_SAMPLERATE_SPECIAL;
                 break;

             }

         default:

             av_log(enc, AV_LOG_ERROR, "flv does not support that sample rate, choose from (44100, 22050, 11025).\n");

             return -1;
     }

     }

 
     if (enc->channels > 1) {

         flags |= FLV_STEREO;

     }

     switch(enc->codec_id){
     case CODEC_ID_MP3:

         flags |= FLV_CODECID_MP3    | FLV_SAMPLESSIZE_16BIT;

         break;

     case CODEC_ID_PCM_U8:

         flags |= FLV_CODECID_PCM    | FLV_SAMPLESSIZE_8BIT;

         break;

     case CODEC_ID_PCM_S16BE:

         flags |= FLV_CODECID_PCM    | FLV_SAMPLESSIZE_16BIT;

         break;

     case CODEC_ID_PCM_S16LE:

         flags |= FLV_CODECID_PCM_LE | FLV_SAMPLESSIZE_16BIT;

         break;

     case CODEC_ID_ADPCM_SWF:

         flags |= FLV_CODECID_ADPCM | FLV_SAMPLESSIZE_16BIT;

         break;

     case CODEC_ID_NELLYMOSER:

         if (enc->sample_rate == 8000) {
             flags |= FLV_CODECID_NELLYMOSER_8KHZ_MONO | FLV_SAMPLESSIZE_16BIT;
         } else {
             flags |= FLV_CODECID_NELLYMOSER | FLV_SAMPLESSIZE_16BIT;
         }

         break;

     case 0:
         flags |= enc->codec_tag<<4;
         break;
     default:

         av_log(enc, AV_LOG_ERROR, "codec not compatible with flv\n");

         return -1;
     }

     return flags;
 }
 

 static void put_amf_string(AVIOContext *pb, const char *str)

 {
     size_t len = strlen(str);

     avio_wb16(pb, len);
     avio_write(pb, str, len);

 }
 

 static void put_avc_eos_tag(AVIOContext *pb, unsigned ts) {

     avio_w8(pb, FLV_TAG_TYPE_VIDEO);
     avio_wb24(pb, 5);  /* Tag Data Size */
     avio_wb24(pb, ts);  /* lower 24 bits of timestamp in ms*/
     avio_w8(pb, (ts >> 24) & 0x7F);  /* MSB of ts in ms*/
     avio_wb24(pb, 0);  /* StreamId = 0 */
     avio_w8(pb, 23);  /* ub[4] FrameType = 1, ub[4] CodecId = 7 */
     avio_w8(pb, 2);  /* AVC end of sequence */
     avio_wb24(pb, 0);  /* Always 0 for AVC EOS. */
     avio_wb32(pb, 16);  /* Size of FLV tag */

 }
 

 static void put_amf_double(AVIOContext *pb, double d)

 {

     avio_w8(pb, AMF_DATA_TYPE_NUMBER);
     avio_wb64(pb, av_dbl2int(d));

 }
 

 static void put_amf_bool(AVIOContext *pb, int b) {

     avio_w8(pb, AMF_DATA_TYPE_BOOL);
     avio_w8(pb, !!b);

 }
 

 static int flv_write_header(AVFormatContext *s)
 {

     AVIOContext *pb = s->pb;

     FLVContext *flv = s->priv_data;

     AVCodecContext *audio_enc = NULL, *video_enc = NULL;
     int i;

     double framerate = 0.0;

     int64_t metadata_size_pos, data_size;

     AVDictionaryEntry *tag = NULL;

     for(i=0; i<s->nb_streams; i++){

         AVCodecContext *enc = s->streams[i]->codec;

         if (enc->codec_type == AVMEDIA_TYPE_VIDEO) {

             if (s->streams[i]->r_frame_rate.den && s->streams[i]->r_frame_rate.num) {
                 framerate = av_q2d(s->streams[i]->r_frame_rate);
             } else {
                 framerate = 1/av_q2d(s->streams[i]->codec->time_base);
             }

             video_enc = enc;
             if(enc->codec_tag == 0) {

                 av_log(enc, AV_LOG_ERROR, "video codec not compatible with flv\n");
                 return -1;
             }

         } else {

             audio_enc = enc;

             if(get_audio_flags(enc)<0)
                 return -1;

         }

         av_set_pts_info(s->streams[i], 32, 1, 1000); /* 32 bit pts in ms */

     }

     avio_write(pb, "FLV", 3);

     avio_w8(pb,1);
     avio_w8(pb,   FLV_HEADER_FLAG_HASAUDIO * !!audio_enc

                  + FLV_HEADER_FLAG_HASVIDEO * !!video_enc);

     avio_wb32(pb,9);
     avio_wb32(pb,0);

 
     for(i=0; i<s->nb_streams; i++){
         if(s->streams[i]->codec->codec_tag == 5){

             avio_w8(pb,8); // message type
             avio_wb24(pb,0); // include flags
             avio_wb24(pb,0); // time stamp
             avio_wb32(pb,0); // reserved
             avio_wb32(pb,11); // size

             flv->reserved=5;
         }
     }

     flv->last_video_ts = -1;
 

     /* write meta_tag */

     avio_w8(pb, 18);         // tag type META

     metadata_size_pos= avio_tell(pb);

     avio_wb24(pb, 0);          // size of data part (sum of all parts below)
     avio_wb24(pb, 0);          // time stamp
     avio_wb32(pb, 0);          // reserved

 
     /* now data of data_size size */
 
     /* first event name as a string */

     avio_w8(pb, AMF_DATA_TYPE_STRING);

     put_amf_string(pb, "onMetaData"); // 12 bytes
 
     /* mixed array (hash) with size and string/type/data tuples */

     avio_w8(pb, AMF_DATA_TYPE_MIXEDARRAY);
     avio_wb32(pb, 5*!!video_enc + 5*!!audio_enc + 2); // +2 for duration and file size

     put_amf_string(pb, "duration");

     flv->duration_offset= avio_tell(pb);

     put_amf_double(pb, s->duration / AV_TIME_BASE); // fill in the guessed duration, it'll be corrected later if incorrect

     if(video_enc){

         put_amf_string(pb, "width");

         put_amf_double(pb, video_enc->width);

 
         put_amf_string(pb, "height");

         put_amf_double(pb, video_enc->height);

 
         put_amf_string(pb, "videodatarate");

         put_amf_double(pb, video_enc->bit_rate / 1024.0);

 
         put_amf_string(pb, "framerate");
         put_amf_double(pb, framerate);

 
         put_amf_string(pb, "videocodecid");

         put_amf_double(pb, video_enc->codec_tag);

     }
 

     if(audio_enc){

         put_amf_string(pb, "audiodatarate");
         put_amf_double(pb, audio_enc->bit_rate / 1024.0);
 

         put_amf_string(pb, "audiosamplerate");

         put_amf_double(pb, audio_enc->sample_rate);

 
         put_amf_string(pb, "audiosamplesize");

         put_amf_double(pb, audio_enc->codec_id == CODEC_ID_PCM_U8 ? 8 : 16);

 
         put_amf_string(pb, "stereo");

         put_amf_bool(pb, audio_enc->channels == 2);

 
         put_amf_string(pb, "audiocodecid");

         put_amf_double(pb, audio_enc->codec_tag);

     }
 

     while ((tag = av_dict_get(s->metadata, "", tag, AV_DICT_IGNORE_SUFFIX))) {

         put_amf_string(pb, tag->key);

         avio_w8(pb, AMF_DATA_TYPE_STRING);

         put_amf_string(pb, tag->value);
     }
 

     put_amf_string(pb, "filesize");

     flv->filesize_offset= avio_tell(pb);

     put_amf_double(pb, 0); // delayed write

 
     put_amf_string(pb, "");

     avio_w8(pb, AMF_END_OF_OBJECT);

 
     /* write total size of tag */

     data_size= avio_tell(pb) - metadata_size_pos - 10;

     avio_seek(pb, metadata_size_pos, SEEK_SET);

     avio_wb24(pb, data_size);

     avio_skip(pb, data_size + 10 - 3);

     avio_wb32(pb, data_size + 11);

     for (i = 0; i < s->nb_streams; i++) {
         AVCodecContext *enc = s->streams[i]->codec;
         if (enc->codec_id == CODEC_ID_AAC || enc->codec_id == CODEC_ID_H264) {

             int64_t pos;

             avio_w8(pb, enc->codec_type == AVMEDIA_TYPE_VIDEO ?

                      FLV_TAG_TYPE_VIDEO : FLV_TAG_TYPE_AUDIO);

             avio_wb24(pb, 0); // size patched later
             avio_wb24(pb, 0); // ts
             avio_w8(pb, 0); // ts ext
             avio_wb24(pb, 0); // streamid

             pos = avio_tell(pb);

             if (enc->codec_id == CODEC_ID_AAC) {

                 avio_w8(pb, get_audio_flags(enc));
                 avio_w8(pb, 0); // AAC sequence header
                 avio_write(pb, enc->extradata, enc->extradata_size);

             } else {

                 avio_w8(pb, enc->codec_tag | FLV_FRAME_KEY); // flags
                 avio_w8(pb, 0); // AVC sequence header
                 avio_wb24(pb, 0); // composition time

                 ff_isom_write_avcc(pb, enc->extradata, enc->extradata_size);
             }

             data_size = avio_tell(pb) - pos;

             avio_seek(pb, -data_size - 10, SEEK_CUR);

             avio_wb24(pb, data_size);

             avio_skip(pb, data_size + 10 - 3);

             avio_wb32(pb, data_size + 11); // previous tag size

         }
     }
 

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

     int64_t file_size;
 

     AVIOContext *pb = s->pb;

     FLVContext *flv = s->priv_data;

     int i;
 
     /* Add EOS tag */
     for (i = 0; i < s->nb_streams; i++) {
         AVCodecContext *enc = s->streams[i]->codec;

         if (enc->codec_type == AVMEDIA_TYPE_VIDEO &&

                 enc->codec_id == CODEC_ID_H264) {
             put_avc_eos_tag(pb, flv->last_video_ts);
         }
     }

     file_size = avio_tell(pb);

 
     /* update informations */

     avio_seek(pb, flv->duration_offset, SEEK_SET);

     put_amf_double(pb, flv->duration / (double)1000);

     avio_seek(pb, flv->filesize_offset, SEEK_SET);

     put_amf_double(pb, file_size);
 

     avio_seek(pb, file_size, SEEK_SET);

     return 0;
 }
 

 static int flv_write_packet(AVFormatContext *s, AVPacket *pkt)

 {

     AVIOContext *pb = s->pb;

     AVCodecContext *enc = s->streams[pkt->stream_index]->codec;

     FLVContext *flv = s->priv_data;

     unsigned ts;

     int size= pkt->size;

     uint8_t *data= NULL;

     int flags, flags_size;

 //    av_log(s, AV_LOG_DEBUG, "type:%d pts: %"PRId64" size:%d\n", enc->codec_type, timestamp, size);

     if(enc->codec_id == CODEC_ID_VP6 || enc->codec_id == CODEC_ID_VP6F ||
        enc->codec_id == CODEC_ID_AAC)

         flags_size= 2;

     else if(enc->codec_id == CODEC_ID_H264)
         flags_size= 5;

     else
         flags_size= 1;
 

     if (enc->codec_type == AVMEDIA_TYPE_VIDEO) {

         avio_w8(pb, FLV_TAG_TYPE_VIDEO);

         flags = enc->codec_tag;

         if(flags == 0) {
             av_log(enc, AV_LOG_ERROR, "video codec %X not compatible with flv\n",enc->codec_id);
             return -1;
         }
 

         flags |= pkt->flags & AV_PKT_FLAG_KEY ? FLV_FRAME_KEY : FLV_FRAME_INTER;

     } else {

         assert(enc->codec_type == AVMEDIA_TYPE_AUDIO);

         flags = get_audio_flags(enc);

         assert(size);
 

         avio_w8(pb, FLV_TAG_TYPE_AUDIO);

     }
 

     if (enc->codec_id == CODEC_ID_H264) {

         /* check if extradata looks like mp4 formated */
         if (enc->extradata_size > 0 && *(uint8_t*)enc->extradata != 1) {
             if (ff_avc_parse_nal_units_buf(pkt->data, &data, &size) < 0)
                 return -1;
         }

         if (!flv->delay && pkt->dts < 0)
             flv->delay = -pkt->dts;

     } else if (enc->codec_id == CODEC_ID_AAC && pkt->size > 2 &&
                (AV_RB16(pkt->data) & 0xfff0) == 0xfff0) {
         av_log(s, AV_LOG_ERROR, "malformated aac bitstream, use -absf aac_adtstoasc\n");
         return -1;

     }
 
     ts = pkt->dts + flv->delay; // add delay to force positive dts

     if (enc->codec_type == AVMEDIA_TYPE_VIDEO) {

         if (flv->last_video_ts < ts)
             flv->last_video_ts = ts;
     }

     avio_wb24(pb,size + flags_size);
     avio_wb24(pb,ts);
     avio_w8(pb,(ts >> 24) & 0x7F); // timestamps are 32bits _signed_
     avio_wb24(pb,flv->reserved);
     avio_w8(pb,flags);

     if (enc->codec_id == CODEC_ID_VP6)

         avio_w8(pb,0);

     if (enc->codec_id == CODEC_ID_VP6F)

         avio_w8(pb, enc->extradata_size ? enc->extradata[0] : 0);

     else if (enc->codec_id == CODEC_ID_AAC)

         avio_w8(pb,1); // AAC raw

     else if (enc->codec_id == CODEC_ID_H264) {

         avio_w8(pb,1); // AVC NALU
         avio_wb24(pb,pkt->pts - pkt->dts);

     }

     avio_write(pb, data ? data : pkt->data, size);

     avio_wb32(pb,size+flags_size+11); // previous tag size

     flv->duration = FFMAX(flv->duration, pkt->pts + flv->delay + pkt->duration);

     avio_flush(pb);

 
     av_free(data);
 

     return pb->error;

 }
 

 AVOutputFormat ff_flv_muxer = {

     "flv",

     NULL_IF_CONFIG_SMALL("FLV format"),

     "video/x-flv",

     "flv",
     sizeof(FLVContext),

 #if CONFIG_LIBMP3LAME

     CODEC_ID_MP3,

 #else // CONFIG_LIBMP3LAME

     CODEC_ID_ADPCM_SWF,

 #endif // CONFIG_LIBMP3LAME

     CODEC_ID_FLV1,
     flv_write_header,
     flv_write_packet,
     flv_write_trailer,

     .codec_tag= (const AVCodecTag* const []){flv_video_codec_ids, flv_audio_codec_ids, 0},

     .flags= AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS,

 };