/*
  * Copyright (c) 2012 Martin Storsjo
  *
  * This file is part of Libav.
  *
  * Libav 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.
  *
  * Libav 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 Libav; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 /*
  * To create a simple file for smooth streaming:

  * ffmpeg <normal input/transcoding options> -movflags frag_keyframe foo.ismv

  * ismindex -n foo foo.ismv
  * This step creates foo.ism and foo.ismc that is required by IIS for
  * serving it.
  *
  * To pre-split files for serving as static files by a web server without
  * any extra server support, create the ismv file as above, and split it:
  * ismindex -split foo.ismv
  * This step creates a file Manifest and directories QualityLevel(...),
  * that can be read directly by a smooth streaming player.
  */
 
 #include <stdio.h>
 #include <string.h>
 #include <sys/stat.h>

 #ifdef _WIN32

 #include <direct.h>
 #define mkdir(a, b) _mkdir(a)

 #endif

 #include "cmdutils.h"
 

 #include "libavformat/avformat.h"
 #include "libavutil/intreadwrite.h"
 #include "libavutil/mathematics.h"
 
 static int usage(const char *argv0, int ret)
 {
     fprintf(stderr, "%s [-split] [-n basename] file1 [file2] ...\n", argv0);
     return ret;
 }
 
 struct MoofOffset {
     int64_t time;
     int64_t offset;
     int duration;
 };
 

 struct Track {

     const char *name;
     int64_t duration;
     int bitrate;
     int track_id;
     int is_audio, is_video;
     int width, height;
     int chunks;
     int sample_rate, channels;
     uint8_t *codec_private;
     int codec_private_size;
     struct MoofOffset *offsets;
     int timescale;
     const char *fourcc;
     int blocksize;
     int tag;
 };
 

 struct Tracks {
     int nb_tracks;

     int64_t duration;

     struct Track **tracks;
     int video_track, audio_track;
     int nb_video_tracks, nb_audio_tracks;

 };
 
 static int copy_tag(AVIOContext *in, AVIOContext *out, int32_t tag_name)
 {
     int32_t size, tag;
 
     size = avio_rb32(in);

     tag  = avio_rb32(in);

     avio_wb32(out, size);
     avio_wb32(out, tag);
     if (tag != tag_name)
         return -1;
     size -= 8;
     while (size > 0) {
         char buf[1024];
         int len = FFMIN(sizeof(buf), size);
         if (avio_read(in, buf, len) != len)
             break;
         avio_write(out, buf, len);
         size -= len;
     }
     return 0;
 }
 
 static int write_fragment(const char *filename, AVIOContext *in)
 {
     AVIOContext *out = NULL;
     int ret;
 
     if ((ret = avio_open2(&out, filename, AVIO_FLAG_WRITE, NULL, NULL)) < 0)
         return ret;
     copy_tag(in, out, MKBETAG('m', 'o', 'o', 'f'));
     copy_tag(in, out, MKBETAG('m', 'd', 'a', 't'));
 
     avio_flush(out);
     avio_close(out);
 
     return ret;
 }
 

 static int write_fragments(struct Tracks *tracks, int start_index,

                            AVIOContext *in)
 {
     char dirname[100], filename[500];
     int i, j;
 

     for (i = start_index; i < tracks->nb_tracks; i++) {
         struct Track *track = tracks->tracks[i];
         const char *type    = track->is_video ? "video" : "audio";
         snprintf(dirname, sizeof(dirname), "QualityLevels(%d)", track->bitrate);

         if (mkdir(dirname, 0777) == -1)
             return AVERROR(errno);

         for (j = 0; j < track->chunks; j++) {

             snprintf(filename, sizeof(filename), "%s/Fragments(%s=%"PRId64")",

                      dirname, type, track->offsets[j].time);
             avio_seek(in, track->offsets[j].offset, SEEK_SET);

             write_fragment(filename, in);
         }
     }
     return 0;
 }
 

 static int read_tfra(struct Tracks *tracks, int start_index, AVIOContext *f)

 {
     int ret = AVERROR_EOF, track_id;
     int version, fieldlength, i, j;

     int64_t pos   = avio_tell(f);

     uint32_t size = avio_rb32(f);

     struct Track *track = NULL;

 
     if (avio_rb32(f) != MKBETAG('t', 'f', 'r', 'a'))
         goto fail;
     version = avio_r8(f);
     avio_rb24(f);
     track_id = avio_rb32(f); /* track id */

     for (i = start_index; i < tracks->nb_tracks && !track; i++)
         if (tracks->tracks[i]->track_id == track_id)
             track = tracks->tracks[i];
     if (!track) {

         /* Ok, continue parsing the next atom */
         ret = 0;
         goto fail;
     }
     fieldlength = avio_rb32(f);

     track->chunks  = avio_rb32(f);
     track->offsets = av_mallocz(sizeof(*track->offsets) * track->chunks);
     if (!track->offsets) {

         ret = AVERROR(ENOMEM);
         goto fail;
     }

     for (i = 0; i < track->chunks; i++) {

         if (version == 1) {

             track->offsets[i].time   = avio_rb64(f);
             track->offsets[i].offset = avio_rb64(f);

         } else {

             track->offsets[i].time   = avio_rb32(f);
             track->offsets[i].offset = avio_rb32(f);

         }
         for (j = 0; j < ((fieldlength >> 4) & 3) + 1; j++)
             avio_r8(f);
         for (j = 0; j < ((fieldlength >> 2) & 3) + 1; j++)
             avio_r8(f);
         for (j = 0; j < ((fieldlength >> 0) & 3) + 1; j++)
             avio_r8(f);
         if (i > 0)

             track->offsets[i - 1].duration = track->offsets[i].time -
                                              track->offsets[i - 1].time;

     }

     if (track->chunks > 0)
         track->offsets[track->chunks - 1].duration = track->duration -
                                                      track->offsets[track->chunks - 1].time;

     ret = 0;

 fail:
     avio_seek(f, pos + size, SEEK_SET);
     return ret;
 }
 

 static int read_mfra(struct Tracks *tracks, int start_index,

                      const char *file, int split)
 {
     int err = 0;
     AVIOContext *f = NULL;
     int32_t mfra_size;
 
     if ((err = avio_open2(&f, file, AVIO_FLAG_READ, NULL, NULL)) < 0)
         goto fail;
     avio_seek(f, avio_size(f) - 4, SEEK_SET);
     mfra_size = avio_rb32(f);
     avio_seek(f, -mfra_size, SEEK_CUR);

     if (avio_rb32(f) != mfra_size) {
         err = AVERROR_INVALIDDATA;

         goto fail;

     }
     if (avio_rb32(f) != MKBETAG('m', 'f', 'r', 'a')) {
         err = AVERROR_INVALIDDATA;

         goto fail;

     }

     while (!read_tfra(tracks, start_index, f)) {

         /* Empty */
     }
 
     if (split)

         err = write_fragments(tracks, start_index, f);

 
 fail:
     if (f)
         avio_close(f);

     if (err)
         fprintf(stderr, "Unable to read the MFRA atom in %s\n", file);

     return err;
 }
 

 static int get_private_data(struct Track *track, AVCodecContext *codec)

 {

     track->codec_private_size = codec->extradata_size;
     track->codec_private      = av_mallocz(codec->extradata_size);
     if (!track->codec_private)

         return AVERROR(ENOMEM);

     memcpy(track->codec_private, codec->extradata, codec->extradata_size);

     return 0;
 }
 

 static int get_video_private_data(struct Track *track, AVCodecContext *codec)

 {
     AVIOContext *io = NULL;
     uint16_t sps_size, pps_size;
     int err = AVERROR(EINVAL);
 

     if (codec->codec_id == AV_CODEC_ID_VC1)

         return get_private_data(track, codec);

     if (avio_open_dyn_buf(&io) < 0)  {
         err = AVERROR(ENOMEM);
         goto fail;
     }

     if (codec->extradata_size < 11 || codec->extradata[0] != 1)
         goto fail;
     sps_size = AV_RB16(&codec->extradata[6]);
     if (11 + sps_size > codec->extradata_size)
         goto fail;
     avio_wb32(io, 0x00000001);
     avio_write(io, &codec->extradata[8], sps_size);
     pps_size = AV_RB16(&codec->extradata[9 + sps_size]);
     if (11 + sps_size + pps_size > codec->extradata_size)
         goto fail;
     avio_wb32(io, 0x00000001);
     avio_write(io, &codec->extradata[11 + sps_size], pps_size);
     err = 0;

 fail:

     track->codec_private_size = avio_close_dyn_buf(io, &track->codec_private);

     return err;
 }
 

 static int handle_file(struct Tracks *tracks, const char *file, int split)

 {
     AVFormatContext *ctx = NULL;

     int err = 0, i, orig_tracks = tracks->nb_tracks;

     char errbuf[50], *ptr;

     struct Track *track;

 
     err = avformat_open_input(&ctx, file, NULL, NULL);
     if (err < 0) {
         av_strerror(err, errbuf, sizeof(errbuf));
         fprintf(stderr, "Unable to open %s: %s\n", file, errbuf);
         return 1;
     }
 
     err = avformat_find_stream_info(ctx, NULL);
     if (err < 0) {
         av_strerror(err, errbuf, sizeof(errbuf));
         fprintf(stderr, "Unable to identify %s: %s\n", file, errbuf);
         goto fail;
     }
 
     if (ctx->nb_streams < 1) {
         fprintf(stderr, "No streams found in %s\n", file);
         goto fail;
     }

     if (!tracks->duration)
         tracks->duration = ctx->duration;

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

         struct Track **temp;

         AVStream *st = ctx->streams[i];

         track = av_mallocz(sizeof(*track));

         if (!track) {
             err = AVERROR(ENOMEM);
             goto fail;
         }
         temp = av_realloc(tracks->tracks,
                           sizeof(*tracks->tracks) * (tracks->nb_tracks + 1));
         if (!temp) {
             av_free(track);
             err = AVERROR(ENOMEM);
             goto fail;
         }
         tracks->tracks = temp;

         tracks->tracks[tracks->nb_tracks] = track;

         track->name = file;

         if ((ptr = strrchr(file, '/')) != NULL)

             track->name = ptr + 1;

         track->bitrate   = st->codec->bit_rate;
         track->track_id  = st->id;
         track->timescale = st->time_base.den;
         track->duration  = av_rescale_rnd(ctx->duration, track->timescale,
                                           AV_TIME_BASE, AV_ROUND_UP);
         track->is_audio  = st->codec->codec_type == AVMEDIA_TYPE_AUDIO;
         track->is_video  = st->codec->codec_type == AVMEDIA_TYPE_VIDEO;

         if (!track->is_audio && !track->is_video) {

             fprintf(stderr,
                     "Track %d in %s is neither video nor audio, skipping\n",

                     track->track_id, file);
             av_freep(&tracks->tracks[tracks->nb_tracks]);

             continue;
         }
 

         if (track->is_audio) {
             if (tracks->audio_track < 0)
                 tracks->audio_track = tracks->nb_tracks;
             tracks->nb_audio_tracks++;
             track->channels    = st->codec->channels;
             track->sample_rate = st->codec->sample_rate;

             if (st->codec->codec_id == AV_CODEC_ID_AAC) {

                 track->fourcc    = "AACL";
                 track->tag       = 255;
                 track->blocksize = 4;

             } else if (st->codec->codec_id == AV_CODEC_ID_WMAPRO) {

                 track->fourcc    = "WMAP";
                 track->tag       = st->codec->codec_tag;
                 track->blocksize = st->codec->block_align;

             }

             get_private_data(track, st->codec);

         }

         if (track->is_video) {
             if (tracks->video_track < 0)
                 tracks->video_track = tracks->nb_tracks;
             tracks->nb_video_tracks++;
             track->width  = st->codec->width;
             track->height = st->codec->height;

             if (st->codec->codec_id == AV_CODEC_ID_H264)

                 track->fourcc = "H264";

             else if (st->codec->codec_id == AV_CODEC_ID_VC1)

                 track->fourcc = "WVC1";
             get_video_private_data(track, st->codec);

         }
 

         tracks->nb_tracks++;

     }
 
     avformat_close_input(&ctx);
 

     err = read_mfra(tracks, orig_tracks, file, split);

 
 fail:
     if (ctx)
         avformat_close_input(&ctx);
     return err;
 }
 

 static void output_server_manifest(struct Tracks *tracks,

                                    const char *basename)
 {
     char filename[1000];
     FILE *out;
     int i;
 
     snprintf(filename, sizeof(filename), "%s.ism", basename);
     out = fopen(filename, "w");
     if (!out) {
         perror(filename);
         return;
     }
     fprintf(out, "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n");
     fprintf(out, "<smil xmlns=\"http://www.w3.org/2001/SMIL20/Language\">\n");
     fprintf(out, "\t<head>\n");
     fprintf(out, "\t\t<meta name=\"clientManifestRelativePath\" "
                  "content=\"%s.ismc\" />\n", basename);
     fprintf(out, "\t</head>\n");
     fprintf(out, "\t<body>\n");
     fprintf(out, "\t\t<switch>\n");

     for (i = 0; i < tracks->nb_tracks; i++) {
         struct Track *track = tracks->tracks[i];
         const char *type    = track->is_video ? "video" : "audio";

         fprintf(out, "\t\t\t<%s src=\"%s\" systemBitrate=\"%d\">\n",

                 type, track->name, track->bitrate);

         fprintf(out, "\t\t\t\t<param name=\"trackID\" value=\"%d\" "

                      "valueType=\"data\" />\n", track->track_id);

         fprintf(out, "\t\t\t</%s>\n", type);
     }
     fprintf(out, "\t\t</switch>\n");
     fprintf(out, "\t</body>\n");
     fprintf(out, "</smil>\n");
     fclose(out);
 }
 

 static void print_track_chunks(FILE *out, struct Tracks *tracks, int main,
                                const char *type)
 {
     int i, j;
     struct Track *track = tracks->tracks[main];
     for (i = 0; i < track->chunks; i++) {
         for (j = main + 1; j < tracks->nb_tracks; j++) {
             if (tracks->tracks[j]->is_audio == track->is_audio &&
                 track->offsets[i].duration != tracks->tracks[j]->offsets[i].duration)
                 fprintf(stderr, "Mismatched duration of %s chunk %d in %s and %s\n",
                         type, i, track->name, tracks->tracks[j]->name);
         }
         fprintf(out, "\t\t<c n=\"%d\" d=\"%d\" />\n",
                 i, track->offsets[i].duration);
     }
 }
 

 static void output_client_manifest(struct Tracks *tracks,

                                    const char *basename, int split)
 {
     char filename[1000];
     FILE *out;
     int i, j;
 
     if (split)
         snprintf(filename, sizeof(filename), "Manifest");
     else
         snprintf(filename, sizeof(filename), "%s.ismc", basename);
     out = fopen(filename, "w");
     if (!out) {
         perror(filename);
         return;
     }
     fprintf(out, "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n");
     fprintf(out, "<SmoothStreamingMedia MajorVersion=\"2\" MinorVersion=\"0\" "

                  "Duration=\"%"PRId64 "\">\n", tracks->duration * 10);
     if (tracks->video_track >= 0) {
         struct Track *track = tracks->tracks[tracks->video_track];
         struct Track *first_track = track;

         int index = 0;

         fprintf(out,
                 "\t<StreamIndex Type=\"video\" QualityLevels=\"%d\" "
                 "Chunks=\"%d\" "
                 "Url=\"QualityLevels({bitrate})/Fragments(video={start time})\">\n",

                 tracks->nb_video_tracks, track->chunks);
         for (i = 0; i < tracks->nb_tracks; i++) {
             track = tracks->tracks[i];
             if (!track->is_video)

                 continue;

             fprintf(out,
                     "\t\t<QualityLevel Index=\"%d\" Bitrate=\"%d\" "
                     "FourCC=\"%s\" MaxWidth=\"%d\" MaxHeight=\"%d\" "
                     "CodecPrivateData=\"",

                     index, track->bitrate, track->fourcc, track->width, track->height);
             for (j = 0; j < track->codec_private_size; j++)
                 fprintf(out, "%02X", track->codec_private[j]);

             fprintf(out, "\" />\n");
             index++;

             if (track->chunks != first_track->chunks)

                 fprintf(stderr, "Mismatched number of video chunks in %s and %s\n",

                         track->name, first_track->name);

         }

         print_track_chunks(out, tracks, tracks->video_track, "video");

         fprintf(out, "\t</StreamIndex>\n");
     }

     if (tracks->audio_track >= 0) {
         struct Track *track = tracks->tracks[tracks->audio_track];
         struct Track *first_track = track;

         int index = 0;

         fprintf(out,
                 "\t<StreamIndex Type=\"audio\" QualityLevels=\"%d\" "
                 "Chunks=\"%d\" "
                 "Url=\"QualityLevels({bitrate})/Fragments(audio={start time})\">\n",

                 tracks->nb_audio_tracks, track->chunks);
         for (i = 0; i < tracks->nb_tracks; i++) {
             track = tracks->tracks[i];
             if (!track->is_audio)

                 continue;

             fprintf(out,
                     "\t\t<QualityLevel Index=\"%d\" Bitrate=\"%d\" "
                     "FourCC=\"%s\" SamplingRate=\"%d\" Channels=\"%d\" "
                     "BitsPerSample=\"16\" PacketSize=\"%d\" "
                     "AudioTag=\"%d\" CodecPrivateData=\"",

                     index, track->bitrate, track->fourcc, track->sample_rate,
                     track->channels, track->blocksize, track->tag);
             for (j = 0; j < track->codec_private_size; j++)
                 fprintf(out, "%02X", track->codec_private[j]);

             fprintf(out, "\" />\n");
             index++;

             if (track->chunks != first_track->chunks)

                 fprintf(stderr, "Mismatched number of audio chunks in %s and %s\n",

                         track->name, first_track->name);

         }

         print_track_chunks(out, tracks, tracks->audio_track, "audio");

         fprintf(out, "\t</StreamIndex>\n");
     }
     fprintf(out, "</SmoothStreamingMedia>\n");
     fclose(out);
 }
 

 static void clean_tracks(struct Tracks *tracks)

 {
     int i;

     for (i = 0; i < tracks->nb_tracks; i++) {
         av_freep(&tracks->tracks[i]->codec_private);
         av_freep(&tracks->tracks[i]->offsets);
         av_freep(&tracks->tracks[i]);

     }

     av_freep(&tracks->tracks);
     tracks->nb_tracks = 0;

 }
 
 int main(int argc, char **argv)
 {
     const char *basename = NULL;
     int split = 0, i;

     struct Tracks tracks = { 0, .video_track = -1, .audio_track = -1 };

 
     av_register_all();
 
     for (i = 1; i < argc; i++) {
         if (!strcmp(argv[i], "-n")) {
             basename = argv[i + 1];
             i++;
         } else if (!strcmp(argv[i], "-split")) {
             split = 1;
         } else if (argv[i][0] == '-') {
             return usage(argv[0], 1);
         } else {

             if (handle_file(&tracks, argv[i], split))

                 return 1;

         }
     }

     if (!tracks.nb_tracks || (!basename && !split))

         return usage(argv[0], 1);
 
     if (!split)

         output_server_manifest(&tracks, basename);
     output_client_manifest(&tracks, basename, split);

     clean_tracks(&tracks);

 
     return 0;
 }