/*
  * General DV muxer/demuxer
  * Copyright (c) 2003 Roman Shaposhnik
  *
  * Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth
  * of DV technical info.
  *
  * Raw DV format

  * Copyright (c) 2002 Fabrice Bellard

  *
  * 50 Mbps (DVCPRO50) support
  * Copyright (c) 2006 Daniel Maas <dmaas@maasdigital.com>
  *

  * 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 <time.h>

 #include <stdarg.h>

 #include "avformat.h"

 #include "internal.h"

 #include "libavcodec/dv_profile.h"

 #include "libavcodec/dv.h"

 #include "dv.h"

 #include "libavutil/fifo.h"

 #include "libavutil/mathematics.h"

 #include "libavutil/intreadwrite.h"
 #include "libavutil/opt.h"

 #include "libavutil/timecode.h"

 #define MAX_AUDIO_FRAME_SIZE 192000 // 1 second of 48khz 32bit audio
 

 struct DVMuxContext {

     AVClass          *av_class;

     const AVDVProfile*  sys;           /* current DV profile, e.g.: 525/60, 625/50 */

     int               n_ast;         /* number of stereo audio streams (up to 2) */
     AVStream         *ast[2];        /* stereo audio streams */

     AVFifoBuffer     *audio_data[2]; /* FIFO for storing excessive amounts of PCM */

     int               frames;        /* current frame number */

     int64_t           start_time;    /* recording start time */

     int               has_audio;     /* frame under construction has audio */
     int               has_video;     /* frame under construction has video */
     uint8_t           frame_buf[DV_MAX_FRAME_SIZE]; /* frame under construction */

     AVTimecode        tc;            /* timecode context */

 };
 
 static const int dv_aaux_packs_dist[12][9] = {
     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
 };
 

 static int dv_audio_frame_size(const AVDVProfile* sys, int frame, int sample_rate)

 {

     if ((sys->time_base.den == 25 || sys->time_base.den == 50) && sys->time_base.num == 1) {
         if      (sample_rate == 32000) return 1280;
         else if (sample_rate == 44100) return 1764;
         else                           return 1920;
     }
 
     av_assert0(sample_rate == 48000);
 

     return sys->audio_samples_dist[frame % (sizeof(sys->audio_samples_dist) /

                                             sizeof(sys->audio_samples_dist[0]))];
 }
 

 static int dv_write_pack(enum dv_pack_type pack_id, DVMuxContext *c, uint8_t* buf, ...)

 {
     struct tm tc;
     time_t ct;

     uint32_t timecode;

     va_list ap;

     int audio_type = 0;
     int channel;

 
     buf[0] = (uint8_t)pack_id;
     switch (pack_id) {
     case dv_timecode:

         timecode  = av_timecode_get_smpte_from_framenum(&c->tc, c->frames);

         timecode |= 1<<23 | 1<<15 | 1<<7 | 1<<6; // biphase and binary group flags
         AV_WB32(buf + 1, timecode);

         break;

     case dv_audio_source:  /* AAUX source pack */

         va_start(ap, buf);

         channel = va_arg(ap, int);
         if (c->ast[channel]->codec->sample_rate == 44100) {
             audio_type = 1;
         } else if (c->ast[channel]->codec->sample_rate == 32000)
             audio_type = 2;

         buf[1] = (1 << 7) | /* locked mode -- SMPTE only supports locked mode */
                  (1 << 6) | /* reserved -- always 1 */

                  (dv_audio_frame_size(c->sys, c->frames, c->ast[channel]->codec->sample_rate) -
                   c->sys->audio_min_samples[audio_type]);

                             /* # of samples      */
         buf[2] = (0 << 7) | /* multi-stereo      */
                  (0 << 5) | /* #of audio channels per block: 0 -- 1 channel */
                  (0 << 4) | /* pair bit: 0 -- one pair of channels */
                  !!va_arg(ap, int); /* audio mode        */
         buf[3] = (1 << 7) | /* res               */
                  (1 << 6) | /* multi-language flag */
                  (c->sys->dsf << 5) | /*  system: 60fields/50fields */
                  (c->sys->n_difchan & 2); /* definition: 0 -- 25Mbps, 2 -- 50Mbps */
         buf[4] = (1 << 7) | /* emphasis: 1 -- off */
                  (0 << 6) | /* emphasis time constant: 0 -- reserved */

                  (audio_type << 3) | /* frequency: 0 -- 48kHz, 1 -- 44,1kHz, 2 -- 32kHz */

                   0;        /* quantization: 0 -- 16bit linear, 1 -- 12bit nonlinear */

         va_end(ap);
         break;

     case dv_audio_control:

         buf[1] = (0 << 6) | /* copy protection: 0 -- unrestricted */
                  (1 << 4) | /* input source: 1 -- digital input */
                  (3 << 2) | /* compression: 3 -- no information */
                   0;        /* misc. info/SMPTE emphasis off */
         buf[2] = (1 << 7) | /* recording start point: 1 -- no */
                  (1 << 6) | /* recording end point: 1 -- no */
                  (1 << 3) | /* recording mode: 1 -- original */
                   7;
         buf[3] = (1 << 7) | /* direction: 1 -- forward */

                  (c->sys->pix_fmt == AV_PIX_FMT_YUV420P ? 0x20 : /* speed */

                                                        c->sys->ltc_divisor * 4);

         buf[4] = (1 << 7) | /* reserved -- always 1 */
                   0x7f;     /* genre category */
         break;

     case dv_audio_recdate:
     case dv_video_recdate:  /* VAUX recording date */

         ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,

                                             c->sys->time_base.den, AV_ROUND_DOWN);

         ff_brktimegm(ct, &tc);

         buf[1] = 0xff; /* ds, tm, tens of time zone, units of time zone */
                        /* 0xff is very likely to be "unknown" */
         buf[2] = (3 << 6) | /* reserved -- always 1 */
                  ((tc.tm_mday / 10) << 4) | /* Tens of day */
                  (tc.tm_mday % 10);         /* Units of day */
         buf[3] = /* we set high 4 bits to 0, shouldn't we set them to week? */
                  ((tc.tm_mon / 10) << 4) |    /* Tens of month */
                  (tc.tm_mon  % 10);           /* Units of month */
         buf[4] = (((tc.tm_year % 100) / 10) << 4) | /* Tens of year */
                  (tc.tm_year % 10);                 /* Units of year */
         break;

     case dv_audio_rectime:  /* AAUX recording time */
     case dv_video_rectime:  /* VAUX recording time */

         ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
                                                        c->sys->time_base.den, AV_ROUND_DOWN);

         ff_brktimegm(ct, &tc);

         buf[1] = (3 << 6) | /* reserved -- always 1 */
                  0x3f; /* tens of frame, units of frame: 0x3f - "unknown" ? */
         buf[2] = (1 << 7) | /* reserved -- always 1 */
                  ((tc.tm_sec / 10) << 4) | /* Tens of seconds */
                  (tc.tm_sec % 10);         /* Units of seconds */
         buf[3] = (1 << 7) | /* reserved -- always 1 */
                  ((tc.tm_min / 10) << 4) | /* Tens of minutes */
                  (tc.tm_min % 10);         /* Units of minutes */
         buf[4] = (3 << 6) | /* reserved -- always 1 */
                  ((tc.tm_hour / 10) << 4) | /* Tens of hours */
                  (tc.tm_hour % 10);         /* Units of hours */
         break;

     default:

         buf[1] = buf[2] = buf[3] = buf[4] = 0xff;

     }
     return 5;
 }
 
 static void dv_inject_audio(DVMuxContext *c, int channel, uint8_t* frame_ptr)
 {
     int i, j, d, of, size;

     size = 4 * dv_audio_frame_size(c->sys, c->frames, c->ast[channel]->codec->sample_rate);

     frame_ptr += channel * c->sys->difseg_size * 150 * 80;
     for (i = 0; i < c->sys->difseg_size; i++) {

         frame_ptr += 6 * 80; /* skip DIF segment header */
         for (j = 0; j < 9; j++) {

             dv_write_pack(dv_aaux_packs_dist[i][j], c, &frame_ptr[3], channel, i >= c->sys->difseg_size/2);

             for (d = 8; d < 80; d+=2) {
                 of = c->sys->audio_shuffle[i][j] + (d - 8)/2 * c->sys->audio_stride;
                 if (of*2 >= size)
                     continue;

                 frame_ptr[d]   = *av_fifo_peek2(c->audio_data[channel], of*2+1); // FIXME: maybe we have to admit
                 frame_ptr[d+1] = *av_fifo_peek2(c->audio_data[channel], of*2);   //        that DV is a big-endian PCM

             }
             frame_ptr += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */
         }

     }
 }
 
 static void dv_inject_metadata(DVMuxContext *c, uint8_t* frame)
 {
     int j, k;
     uint8_t* buf;
 
     for (buf = frame; buf < frame + c->sys->frame_size; buf += 150 * 80) {
         /* DV subcode: 2nd and 3d DIFs */
         for (j = 80; j < 80 * 3; j += 80) {
             for (k = 6; k < 6 * 8; k += 8)
                 dv_write_pack(dv_timecode, c, &buf[j+k]);
 
             if (((long)(buf-frame)/(c->sys->frame_size/(c->sys->difseg_size*c->sys->n_difchan))%c->sys->difseg_size) > 5) { /* FIXME: is this really needed ? */
                 dv_write_pack(dv_video_recdate, c, &buf[j+14]);
                 dv_write_pack(dv_video_rectime, c, &buf[j+22]);
                 dv_write_pack(dv_video_recdate, c, &buf[j+38]);
                 dv_write_pack(dv_video_rectime, c, &buf[j+46]);
             }
         }
 
         /* DV VAUX: 4th, 5th and 6th 3DIFs */
         for (j = 80*3 + 3; j < 80*6; j += 80) {
             dv_write_pack(dv_video_recdate, c, &buf[j+5*2]);
             dv_write_pack(dv_video_rectime, c, &buf[j+5*3]);
             dv_write_pack(dv_video_recdate, c, &buf[j+5*11]);
             dv_write_pack(dv_video_rectime, c, &buf[j+5*12]);
         }
     }
 }
 
 /*
  * The following 3 functions constitute our interface to the world
  */
 

 static int dv_assemble_frame(DVMuxContext *c, AVStream* st,
                              uint8_t* data, int data_size, uint8_t** frame)

 {
     int i, reqasize;
 
     *frame = &c->frame_buf[0];
 
     switch (st->codec->codec_type) {

     case AVMEDIA_TYPE_VIDEO:

         /* FIXME: we have to have more sensible approach than this one */
         if (c->has_video)
             av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient audio data or severe sync problem.\n", c->frames);

         memcpy(*frame, data, c->sys->frame_size);
         c->has_video = 1;
         break;

     case AVMEDIA_TYPE_AUDIO:

         for (i = 0; i < c->n_ast && st != c->ast[i]; i++);

 
           /* FIXME: we have to have more sensible approach than this one */

         if (av_fifo_size(c->audio_data[i]) + data_size >= 100*MAX_AUDIO_FRAME_SIZE)

             av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient video data or severe sync problem.\n", c->frames);

         av_fifo_generic_write(c->audio_data[i], data, data_size, NULL);

         reqasize = 4 * dv_audio_frame_size(c->sys, c->frames, st->codec->sample_rate);
 

         /* Let us see if we've got enough audio for one DV frame. */

         c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);

         break;

     default:

         break;

     }
 

     /* Let us see if we have enough data to construct one DV frame. */

     if (c->has_video == 1 && c->has_audio + 1 == 1 << c->n_ast) {

         dv_inject_metadata(c, *frame);

         c->has_audio = 0;

         for (i=0; i < c->n_ast; i++) {

             dv_inject_audio(c, i, *frame);

             reqasize = 4 * dv_audio_frame_size(c->sys, c->frames, c->ast[i]->codec->sample_rate);

             av_fifo_drain(c->audio_data[i], reqasize);
             c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);

         }
 
         c->has_video = 0;

         c->frames++;
 
         return c->sys->frame_size;
     }
 
     return 0;
 }
 

 static DVMuxContext* dv_init_mux(AVFormatContext* s)

 {

     DVMuxContext *c = s->priv_data;

     AVStream *vst = NULL;

     AVDictionaryEntry *t;

     int i;
 
     /* we support at most 1 video and 2 audio streams */
     if (s->nb_streams > 3)
         return NULL;
 

     c->n_ast  = 0;

     c->ast[0] = c->ast[1] = NULL;
 
     /* We have to sort out where audio and where video stream is */
     for (i=0; i<s->nb_streams; i++) {

         switch (s->streams[i]->codec->codec_type) {

         case AVMEDIA_TYPE_VIDEO:

             if (vst) return NULL;
             vst = s->streams[i];
             break;

         case AVMEDIA_TYPE_AUDIO:

             if (c->n_ast > 1) return NULL;
             c->ast[c->n_ast++] = s->streams[i];
             break;
         default:
             goto bail_out;
         }

     }
 
     /* Some checks -- DV format is very picky about its incoming streams */

     if (!vst || vst->codec->codec_id != AV_CODEC_ID_DVVIDEO)

         goto bail_out;
     for (i=0; i<c->n_ast; i++) {

         if (c->ast[i]) {
             if(c->ast[i]->codec->codec_id    != AV_CODEC_ID_PCM_S16LE ||
                c->ast[i]->codec->channels    != 2)
                 goto bail_out;
             if (c->ast[i]->codec->sample_rate != 48000 &&
                 c->ast[i]->codec->sample_rate != 44100 &&
                 c->ast[i]->codec->sample_rate != 32000    )
                 goto bail_out;
         }

     }

     c->sys = av_dv_codec_profile(vst->codec->width, vst->codec->height, vst->codec->pix_fmt);

     if (!c->sys)
         goto bail_out;
 

     if ((c->sys->time_base.den != 25 && c->sys->time_base.den != 50) || c->sys->time_base.num != 1) {
         if (c->ast[0] && c->ast[0]->codec->sample_rate != 48000)
             goto bail_out;
         if (c->ast[1] && c->ast[1]->codec->sample_rate != 48000)
             goto bail_out;
     }
 

     if ((c->n_ast > 1) && (c->sys->n_difchan < 2)) {

         /* only 1 stereo pair is allowed in 25Mbps mode */
         goto bail_out;
     }
 
     /* Ok, everything seems to be in working order */

     c->frames     = 0;
     c->has_audio  = 0;
     c->has_video  = 0;

     if (t = av_dict_get(s->metadata, "creation_time", NULL, 0))
         c->start_time = ff_iso8601_to_unix_time(t->value);

     for (i=0; i < c->n_ast; i++) {

         if (c->ast[i] && !(c->audio_data[i]=av_fifo_alloc_array(100, MAX_AUDIO_FRAME_SIZE))) {

             while (i > 0) {

                 i--;

                 av_fifo_freep(&c->audio_data[i]);

             }
             goto bail_out;
         }
     }
 
     return c;
 
 bail_out:
     return NULL;
 }
 

 static void dv_delete_mux(DVMuxContext *c)

 {
     int i;
     for (i=0; i < c->n_ast; i++)

         av_fifo_freep(&c->audio_data[i]);

 }
 
 static int dv_write_header(AVFormatContext *s)
 {

     AVRational rate;

     DVMuxContext *dvc = s->priv_data;

     AVDictionaryEntry *tcr = av_dict_get(s->metadata, "timecode", NULL, 0);

     if (!dv_init_mux(s)) {

         av_log(s, AV_LOG_ERROR, "Can't initialize DV format!\n"
                     "Make sure that you supply exactly two streams:\n"

                     "     video: 25fps or 29.97fps, audio: 2ch/48|44|32kHz/PCM\n"

                     "     (50Mbps allows an optional second audio stream)\n");
         return -1;
     }

     rate.num = dvc->sys->ltc_divisor;
     rate.den = 1;

     if (!tcr) { // no global timecode, look into the streams
         int i;
         for (i = 0; i < s->nb_streams; i++) {
             tcr = av_dict_get(s->streams[i]->metadata, "timecode", NULL, 0);
             if (tcr)
                 break;
         }
     }

     if (tcr && av_timecode_init_from_string(&dvc->tc, rate, tcr->value, s) >= 0)
         return 0;

     return av_timecode_init(&dvc->tc, rate, 0, 0, s);

 }
 
 static int dv_write_packet(struct AVFormatContext *s, AVPacket *pkt)
 {
     uint8_t* frame;
     int fsize;
 

     fsize = dv_assemble_frame(s->priv_data, s->streams[pkt->stream_index],

                               pkt->data, pkt->size, &frame);
     if (fsize > 0) {

         avio_write(s->pb, frame, fsize);

     }
     return 0;
 }
 
 /*
  * We might end up with some extra A/V data without matching counterpart.
  * E.g. video data without enough audio to write the complete frame.
  * Currently we simply drop the last frame. I don't know whether this
  * is the best strategy of all
  */
 static int dv_write_trailer(struct AVFormatContext *s)
 {

     dv_delete_mux(s->priv_data);

     return 0;
 }
 

 AVOutputFormat ff_dv_muxer = {

     .name              = "dv",

     .long_name         = NULL_IF_CONFIG_SMALL("DV (Digital Video)"),

     .extensions        = "dv",
     .priv_data_size    = sizeof(DVMuxContext),

     .audio_codec       = AV_CODEC_ID_PCM_S16LE,
     .video_codec       = AV_CODEC_ID_DVVIDEO,

     .write_header      = dv_write_header,
     .write_packet      = dv_write_packet,
     .write_trailer     = dv_write_trailer,

 };