/*
  * WebM DASH Manifest XML muxer
  * Copyright (c) 2014 Vignesh Venkatasubramanian
  *
  * 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
  */
 
 /*
  * WebM DASH Specification:
  * https://sites.google.com/a/webmproject.org/wiki/adaptive-streaming/webm-dash-specification

  * ISO DASH Specification:
  * http://standards.iso.org/ittf/PubliclyAvailableStandards/c065274_ISO_IEC_23009-1_2014.zip

  */
 

 #include <float.h>

 #include <stdint.h>
 #include <string.h>
 
 #include "avformat.h"
 #include "avio_internal.h"
 #include "matroska.h"
 
 #include "libavutil/avstring.h"
 #include "libavutil/dict.h"
 #include "libavutil/opt.h"

 #include "libavutil/time_internal.h"

 
 typedef struct AdaptationSet {
     char id[10];
     int *streams;
     int nb_streams;
 } AdaptationSet;
 
 typedef struct WebMDashMuxContext {
     const AVClass  *class;
     char *adaptation_sets;
     AdaptationSet *as;
     int nb_as;

     int representation_id;

     int is_live;
     int chunk_start_index;
     int chunk_duration;
     char *utc_timing_url;
     double time_shift_buffer_depth;

     int minimum_update_period;

     int debug_mode;

 } WebMDashMuxContext;
 
 static const char *get_codec_name(int codec_id)
 {
     switch (codec_id) {
         case AV_CODEC_ID_VP8:
             return "vp8";
         case AV_CODEC_ID_VP9:
             return "vp9";
         case AV_CODEC_ID_VORBIS:
             return "vorbis";
         case AV_CODEC_ID_OPUS:
             return "opus";
     }
     return NULL;
 }
 
 static double get_duration(AVFormatContext *s)
 {
     int i = 0;
     double max = 0.0;
     for (i = 0; i < s->nb_streams; i++) {
         AVDictionaryEntry *duration = av_dict_get(s->streams[i]->metadata,
                                                   DURATION, NULL, 0);

         if (!duration || atof(duration->value) < 0) continue;

         if (atof(duration->value) > max) max = atof(duration->value);
     }
     return max / 1000;
 }
 

 static int write_header(AVFormatContext *s)

 {

     WebMDashMuxContext *w = s->priv_data;

     double min_buffer_time = 1.0;
     avio_printf(s->pb, "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n");
     avio_printf(s->pb, "<MPD\n");
     avio_printf(s->pb, "  xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n");
     avio_printf(s->pb, "  xmlns=\"urn:mpeg:DASH:schema:MPD:2011\"\n");
     avio_printf(s->pb, "  xsi:schemaLocation=\"urn:mpeg:DASH:schema:MPD:2011\"\n");

     avio_printf(s->pb, "  type=\"%s\"\n", w->is_live ? "dynamic" : "static");
     if (!w->is_live) {
         avio_printf(s->pb, "  mediaPresentationDuration=\"PT%gS\"\n",
                     get_duration(s));
     }
     avio_printf(s->pb, "  minBufferTime=\"PT%gS\"\n", min_buffer_time);
     avio_printf(s->pb, "  profiles=\"%s\"%s",
                 w->is_live ? "urn:mpeg:dash:profile:isoff-live:2011" : "urn:webm:dash:profile:webm-on-demand:2012",
                 w->is_live ? "\n" : ">\n");
     if (w->is_live) {

         time_t local_time = time(NULL);
         struct tm gmt_buffer;
         struct tm *gmt = gmtime_r(&local_time, &gmt_buffer);

         char gmt_iso[21];

         if (!strftime(gmt_iso, 21, "%Y-%m-%dT%H:%M:%SZ", gmt)) {
             return AVERROR_UNKNOWN;
         }

         if (w->debug_mode) {
             av_strlcpy(gmt_iso, "", 1);
         }

         avio_printf(s->pb, "  availabilityStartTime=\"%s\"\n", gmt_iso);

         avio_printf(s->pb, "  timeShiftBufferDepth=\"PT%gS\"\n", w->time_shift_buffer_depth);

         avio_printf(s->pb, "  minimumUpdatePeriod=\"PT%dS\"", w->minimum_update_period);

         avio_printf(s->pb, ">\n");

         if (w->utc_timing_url) {
             avio_printf(s->pb, "<UTCTiming\n");
             avio_printf(s->pb, "  schemeIdUri=\"urn:mpeg:dash:utc:http-iso:2014\"\n");
             avio_printf(s->pb, "  value=\"%s\"/>\n", w->utc_timing_url);
         }

     }

     return 0;

 }
 
 static void write_footer(AVFormatContext *s)
 {

     avio_printf(s->pb, "</MPD>\n");

 }
 
 static int subsegment_alignment(AVFormatContext *s, AdaptationSet *as) {
     int i;
     AVDictionaryEntry *gold = av_dict_get(s->streams[as->streams[0]]->metadata,
                                           CUE_TIMESTAMPS, NULL, 0);

     if (!gold) return 0;

     for (i = 1; i < as->nb_streams; i++) {
         AVDictionaryEntry *ts = av_dict_get(s->streams[as->streams[i]]->metadata,
                                             CUE_TIMESTAMPS, NULL, 0);

         if (!ts || strncmp(gold->value, ts->value, strlen(gold->value))) return 0;

     }
     return 1;
 }
 
 static int bitstream_switching(AVFormatContext *s, AdaptationSet *as) {
     int i;
     AVDictionaryEntry *gold_track_num = av_dict_get(s->streams[as->streams[0]]->metadata,
                                                     TRACK_NUMBER, NULL, 0);
     AVCodecContext *gold_codec = s->streams[as->streams[0]]->codec;

     if (!gold_track_num) return 0;

     for (i = 1; i < as->nb_streams; i++) {
         AVDictionaryEntry *track_num = av_dict_get(s->streams[as->streams[i]]->metadata,
                                                    TRACK_NUMBER, NULL, 0);
         AVCodecContext *codec = s->streams[as->streams[i]]->codec;

         if (!track_num ||

             strncmp(gold_track_num->value, track_num->value, strlen(gold_track_num->value)) ||
             gold_codec->codec_id != codec->codec_id ||
             gold_codec->extradata_size != codec->extradata_size ||
             memcmp(gold_codec->extradata, codec->extradata, codec->extradata_size)) {
             return 0;
         }
     }
     return 1;
 }
 
 /*

  * Writes a Representation within an Adaptation Set. Returns 0 on success and
  * < 0 on failure.
  */

 static int write_representation(AVFormatContext *s, AVStream *stream, char *id,

                                 int output_width, int output_height,
                                 int output_sample_rate) {

     WebMDashMuxContext *w = s->priv_data;

     AVDictionaryEntry *irange = av_dict_get(stream->metadata, INITIALIZATION_RANGE, NULL, 0);
     AVDictionaryEntry *cues_start = av_dict_get(stream->metadata, CUES_START, NULL, 0);
     AVDictionaryEntry *cues_end = av_dict_get(stream->metadata, CUES_END, NULL, 0);
     AVDictionaryEntry *filename = av_dict_get(stream->metadata, FILENAME, NULL, 0);
     AVDictionaryEntry *bandwidth = av_dict_get(stream->metadata, BANDWIDTH, NULL, 0);

     if ((w->is_live && (!filename)) ||
         (!w->is_live && (!irange || !cues_start || !cues_end || !filename || !bandwidth))) {

         return AVERROR_INVALIDDATA;

     }

     avio_printf(s->pb, "<Representation id=\"%s\"", id);
     // FIXME: For live, This should be obtained from the input file or as an AVOption.
     avio_printf(s->pb, " bandwidth=\"%s\"",
                 w->is_live ? (stream->codec->codec_type == AVMEDIA_TYPE_AUDIO ? "128000" : "1000000") : bandwidth->value);

     if (stream->codec->codec_type == AVMEDIA_TYPE_VIDEO && output_width)
         avio_printf(s->pb, " width=\"%d\"", stream->codec->width);
     if (stream->codec->codec_type == AVMEDIA_TYPE_VIDEO && output_height)
         avio_printf(s->pb, " height=\"%d\"", stream->codec->height);

     if (stream->codec->codec_type == AVMEDIA_TYPE_AUDIO && output_sample_rate)

         avio_printf(s->pb, " audioSamplingRate=\"%d\"", stream->codec->sample_rate);

     if (w->is_live) {
         // For live streams, Codec and Mime Type always go in the Representation tag.
         avio_printf(s->pb, " codecs=\"%s\"", get_codec_name(stream->codec->codec_id));
         avio_printf(s->pb, " mimeType=\"%s/webm\"",
                     stream->codec->codec_type == AVMEDIA_TYPE_VIDEO ? "video" : "audio");
         // For live streams, subsegments always start with key frames. So this
         // is always 1.
         avio_printf(s->pb, " startsWithSAP=\"1\"");
         avio_printf(s->pb, ">");
     } else {
         avio_printf(s->pb, ">\n");
         avio_printf(s->pb, "<BaseURL>%s</BaseURL>\n", filename->value);
         avio_printf(s->pb, "<SegmentBase\n");
         avio_printf(s->pb, "  indexRange=\"%s-%s\">\n", cues_start->value, cues_end->value);
         avio_printf(s->pb, "<Initialization\n");
         avio_printf(s->pb, "  range=\"0-%s\" />\n", irange->value);
         avio_printf(s->pb, "</SegmentBase>\n");
     }

     avio_printf(s->pb, "</Representation>\n");
     return 0;
 }
 
 /*
  * Checks if width of all streams are the same. Returns 1 if true, 0 otherwise.
  */
 static int check_matching_width(AVFormatContext *s, AdaptationSet *as) {
     int first_width, i;
     if (as->nb_streams < 2) return 1;
     first_width = s->streams[as->streams[0]]->codec->width;
     for (i = 1; i < as->nb_streams; i++)
         if (first_width != s->streams[as->streams[i]]->codec->width)
           return 0;
     return 1;
 }
 
 /*
  * Checks if height of all streams are the same. Returns 1 if true, 0 otherwise.
  */
 static int check_matching_height(AVFormatContext *s, AdaptationSet *as) {
     int first_height, i;
     if (as->nb_streams < 2) return 1;
     first_height = s->streams[as->streams[0]]->codec->height;
     for (i = 1; i < as->nb_streams; i++)
         if (first_height != s->streams[as->streams[i]]->codec->height)
           return 0;
     return 1;
 }
 
 /*
  * Checks if sample rate of all streams are the same. Returns 1 if true, 0 otherwise.
  */
 static int check_matching_sample_rate(AVFormatContext *s, AdaptationSet *as) {
     int first_sample_rate, i;
     if (as->nb_streams < 2) return 1;
     first_sample_rate = s->streams[as->streams[0]]->codec->sample_rate;
     for (i = 1; i < as->nb_streams; i++)
         if (first_sample_rate != s->streams[as->streams[i]]->codec->sample_rate)
           return 0;
     return 1;
 }
 

 static void free_adaptation_sets(AVFormatContext *s) {
     WebMDashMuxContext *w = s->priv_data;
     int i;
     for (i = 0; i < w->nb_as; i++) {
         av_freep(&w->as[i].streams);
     }
     av_freep(&w->as);
     w->nb_as = 0;
 }
 

 /*

  * Parses a live header filename and computes the representation id,
  * initialization pattern and the media pattern. Pass NULL if you don't want to
  * compute any of those 3. Returns 0 on success and non-zero on failure.
  *
  * Name of the header file should conform to the following pattern:
  * <file_description>_<representation_id>.hdr where <file_description> can be
  * anything. The chunks should be named according to the following pattern:
  * <file_description>_<representation_id>_<chunk_number>.chk
  */
 static int parse_filename(char *filename, char **representation_id,
                           char **initialization_pattern, char **media_pattern) {
     char *underscore_pos = NULL;
     char *period_pos = NULL;
     char *temp_pos = NULL;
     char *filename_str = av_strdup(filename);
     if (!filename_str) return AVERROR(ENOMEM);
     temp_pos = av_stristr(filename_str, "_");
     while (temp_pos) {
         underscore_pos = temp_pos + 1;
         temp_pos = av_stristr(temp_pos + 1, "_");
     }

     if (!underscore_pos) return AVERROR_INVALIDDATA;

     period_pos = av_stristr(underscore_pos, ".");

     if (!period_pos) return AVERROR_INVALIDDATA;

     *(underscore_pos - 1) = 0;
     if (representation_id) {
         *representation_id = av_malloc(period_pos - underscore_pos + 1);
         if (!(*representation_id)) return AVERROR(ENOMEM);
         av_strlcpy(*representation_id, underscore_pos, period_pos - underscore_pos + 1);
     }
     if (initialization_pattern) {
         *initialization_pattern = av_asprintf("%s_$RepresentationID$.hdr",
                                               filename_str);
         if (!(*initialization_pattern)) return AVERROR(ENOMEM);
     }
     if (media_pattern) {
         *media_pattern = av_asprintf("%s_$RepresentationID$_$Number$.chk",
                                      filename_str);
         if (!(*media_pattern)) return AVERROR(ENOMEM);
     }
     av_free(filename_str);
     return 0;
 }
 
 /*

  * Writes an Adaptation Set. Returns 0 on success and < 0 on failure.
  */
 static int write_adaptation_set(AVFormatContext *s, int as_index)
 {
     WebMDashMuxContext *w = s->priv_data;
     AdaptationSet *as = &w->as[as_index];
     AVCodecContext *codec = s->streams[as->streams[0]]->codec;

     AVDictionaryEntry *lang;

     int i;
     static const char boolean[2][6] = { "false", "true" };
     int subsegmentStartsWithSAP = 1;

 
     // Width, Height and Sample Rate will go in the AdaptationSet tag if they
     // are the same for all contained Representations. otherwise, they will go

     // on their respective Representation tag. For live streams, they always go
     // in the Representation tag.

     int width_in_as = 1, height_in_as = 1, sample_rate_in_as = 1;
     if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {

       width_in_as = !w->is_live && check_matching_width(s, as);
       height_in_as = !w->is_live && check_matching_height(s, as);

     } else {

       sample_rate_in_as = !w->is_live && check_matching_sample_rate(s, as);

     }
 

     avio_printf(s->pb, "<AdaptationSet id=\"%s\"", as->id);
     avio_printf(s->pb, " mimeType=\"%s/webm\"",
                 codec->codec_type == AVMEDIA_TYPE_VIDEO ? "video" : "audio");
     avio_printf(s->pb, " codecs=\"%s\"", get_codec_name(codec->codec_id));
 
     lang = av_dict_get(s->streams[as->streams[0]]->metadata, "language", NULL, 0);

     if (lang) avio_printf(s->pb, " lang=\"%s\"", lang->value);

     if (codec->codec_type == AVMEDIA_TYPE_VIDEO && width_in_as)

         avio_printf(s->pb, " width=\"%d\"", codec->width);

     if (codec->codec_type == AVMEDIA_TYPE_VIDEO && height_in_as)

         avio_printf(s->pb, " height=\"%d\"", codec->height);

     if (codec->codec_type == AVMEDIA_TYPE_AUDIO && sample_rate_in_as)

         avio_printf(s->pb, " audioSamplingRate=\"%d\"", codec->sample_rate);
 
     avio_printf(s->pb, " bitstreamSwitching=\"%s\"",
                 boolean[bitstream_switching(s, as)]);
     avio_printf(s->pb, " subsegmentAlignment=\"%s\"",

                 boolean[w->is_live || subsegment_alignment(s, as)]);

 
     for (i = 0; i < as->nb_streams; i++) {
         AVDictionaryEntry *kf = av_dict_get(s->streams[as->streams[i]]->metadata,
                                             CLUSTER_KEYFRAME, NULL, 0);

         if (!w->is_live && (!kf || !strncmp(kf->value, "0", 1))) subsegmentStartsWithSAP = 0;

     }
     avio_printf(s->pb, " subsegmentStartsWithSAP=\"%d\"", subsegmentStartsWithSAP);
     avio_printf(s->pb, ">\n");
 

     if (w->is_live) {
         AVDictionaryEntry *filename =
             av_dict_get(s->streams[as->streams[0]]->metadata, FILENAME, NULL, 0);
         char *initialization_pattern = NULL;
         char *media_pattern = NULL;
         int ret = parse_filename(filename->value, NULL, &initialization_pattern,
                                  &media_pattern);
         if (ret) return ret;
         avio_printf(s->pb, "<ContentComponent id=\"1\" type=\"%s\"/>\n",
                     codec->codec_type == AVMEDIA_TYPE_VIDEO ? "video" : "audio");
         avio_printf(s->pb, "<SegmentTemplate");
         avio_printf(s->pb, " timescale=\"1000\"");
         avio_printf(s->pb, " duration=\"%d\"", w->chunk_duration);
         avio_printf(s->pb, " media=\"%s\"", media_pattern);
         avio_printf(s->pb, " startNumber=\"%d\"", w->chunk_start_index);
         avio_printf(s->pb, " initialization=\"%s\"", initialization_pattern);
         avio_printf(s->pb, "/>\n");
         av_free(initialization_pattern);
         av_free(media_pattern);
     }
 

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

         char *representation_id = NULL;

         int ret;

         if (w->is_live) {
             AVDictionaryEntry *filename =
                 av_dict_get(s->streams[as->streams[i]]->metadata, FILENAME, NULL, 0);

             if (!filename)
                 return AVERROR(EINVAL);
             if (ret = parse_filename(filename->value, &representation_id, NULL, NULL))

                 return ret;

         } else {
             representation_id = av_asprintf("%d", w->representation_id++);

             if (!representation_id) return AVERROR(ENOMEM);

         }

         ret = write_representation(s, s->streams[as->streams[i]],
                                    representation_id, !width_in_as,
                                    !height_in_as, !sample_rate_in_as);

         av_free(representation_id);

         if (ret) return ret;

     }
     avio_printf(s->pb, "</AdaptationSet>\n");
     return 0;
 }
 
 static int to_integer(char *p, int len)
 {
     int ret;
     char *q = av_malloc(sizeof(char) * len);

     if (!q)
         return AVERROR(ENOMEM);

     av_strlcpy(q, p, len);

     ret = atoi(q);
     av_free(q);
     return ret;
 }
 
 static int parse_adaptation_sets(AVFormatContext *s)
 {
     WebMDashMuxContext *w = s->priv_data;
     char *p = w->adaptation_sets;
     char *q;
     enum { new_set, parsed_id, parsing_streams } state;
     // syntax id=0,streams=0,1,2 id=1,streams=3,4 and so on
     state = new_set;
     while (p < w->adaptation_sets + strlen(w->adaptation_sets)) {
         if (*p == ' ')
             continue;
         else if (state == new_set && !strncmp(p, "id=", 3)) {

             void *mem = av_realloc(w->as, sizeof(*w->as) * (w->nb_as + 1));
             if (mem == NULL)

                 return AVERROR(ENOMEM);

             w->as = mem;
             ++w->nb_as;

             w->as[w->nb_as - 1].nb_streams = 0;
             w->as[w->nb_as - 1].streams = NULL;
             p += 3; // consume "id="
             q = w->as[w->nb_as - 1].id;
             while (*p != ',') *q++ = *p++;
             *q = 0;
             p++;
             state = parsed_id;
         } else if (state == parsed_id && !strncmp(p, "streams=", 8)) {
             p += 8; // consume "streams="
             state = parsing_streams;
         } else if (state == parsing_streams) {
             struct AdaptationSet *as = &w->as[w->nb_as - 1];
             q = p;
             while (*q != '\0' && *q != ',' && *q != ' ') q++;
             as->streams = av_realloc(as->streams, sizeof(*as->streams) * ++as->nb_streams);

             if (as->streams == NULL)
                 return AVERROR(ENOMEM);

             as->streams[as->nb_streams - 1] = to_integer(p, q - p + 1);

             if (as->streams[as->nb_streams - 1] < 0) return -1;
             if (*q == '\0') break;
             if (*q == ' ') state = new_set;
             p = ++q;
         } else {
             return -1;
         }
     }
     return 0;
 }
 
 static int webm_dash_manifest_write_header(AVFormatContext *s)
 {
     int i;
     double start = 0.0;

     int ret;

     WebMDashMuxContext *w = s->priv_data;

     ret = parse_adaptation_sets(s);
     if (ret < 0) {

         goto fail;
     }
     ret = write_header(s);
     if (ret < 0) {
         goto fail;

     }

     avio_printf(s->pb, "<Period id=\"0\"");
     avio_printf(s->pb, " start=\"PT%gS\"", start);

     if (!w->is_live) {
         avio_printf(s->pb, " duration=\"PT%gS\"", get_duration(s));
     }

     avio_printf(s->pb, " >\n");
 
     for (i = 0; i < w->nb_as; i++) {

         ret = write_adaptation_set(s, i);
         if (ret < 0) {

             goto fail;

         }

     }
 
     avio_printf(s->pb, "</Period>\n");
     write_footer(s);

 fail:
     free_adaptation_sets(s);
     return ret < 0 ? ret : 0;

 }
 
 static int webm_dash_manifest_write_packet(AVFormatContext *s, AVPacket *pkt)
 {
     return AVERROR_EOF;
 }
 
 static int webm_dash_manifest_write_trailer(AVFormatContext *s)
 {

     free_adaptation_sets(s);

     return 0;
 }
 
 #define OFFSET(x) offsetof(WebMDashMuxContext, x)
 static const AVOption options[] = {
     { "adaptation_sets", "Adaptation sets. Syntax: id=0,streams=0,1,2 id=1,streams=3,4 and so on", OFFSET(adaptation_sets), AV_OPT_TYPE_STRING, { 0 }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },

     { "debug_mode", "[private option - users should never set this]. Create deterministic output", OFFSET(debug_mode), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM },
     { "live", "create a live stream manifest", OFFSET(is_live), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM },

     { "chunk_start_index",  "start index of the chunk", OFFSET(chunk_start_index), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
     { "chunk_duration_ms", "duration of each chunk (in milliseconds)", OFFSET(chunk_duration), AV_OPT_TYPE_INT, {.i64 = 1000}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
     { "utc_timing_url", "URL of the page that will return the UTC timestamp in ISO format", OFFSET(utc_timing_url), AV_OPT_TYPE_STRING, { 0 }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
     { "time_shift_buffer_depth", "Smallest time (in seconds) shifting buffer for which any Representation is guaranteed to be available.", OFFSET(time_shift_buffer_depth), AV_OPT_TYPE_DOUBLE, { .dbl = 60.0 }, 1.0, DBL_MAX, AV_OPT_FLAG_ENCODING_PARAM },

     { "minimum_update_period", "Minimum Update Period (in seconds) of the manifest.", OFFSET(minimum_update_period), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },

     { NULL },
 };
 
 #if CONFIG_WEBM_DASH_MANIFEST_MUXER
 static const AVClass webm_dash_class = {
     .class_name = "WebM DASH Manifest muxer",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,
 };
 
 AVOutputFormat ff_webm_dash_manifest_muxer = {
     .name              = "webm_dash_manifest",
     .long_name         = NULL_IF_CONFIG_SMALL("WebM DASH Manifest"),
     .mime_type         = "application/xml",
     .extensions        = "xml",
     .priv_data_size    = sizeof(WebMDashMuxContext),
     .write_header      = webm_dash_manifest_write_header,
     .write_packet      = webm_dash_manifest_write_packet,
     .write_trailer     = webm_dash_manifest_write_trailer,
     .priv_class        = &webm_dash_class,
 };
 #endif