/*
  * SubRip subtitle demuxer
  * Copyright (c) 2010  Aurelien Jacobs <aurel@gnuage.org>
  *
  * 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 "avformat.h"
 #include "internal.h"
 #include "libavutil/intreadwrite.h"
 
 static int srt_probe(AVProbeData *p)
 {
     unsigned char *ptr = p->buf;
     int i, v, num = 0;
 
     if (AV_RB24(ptr) == 0xEFBBBF)
         ptr += 3;  /* skip UTF-8 BOM */
 
     for (i=0; i<2; i++) {
         if (num == i && sscanf(ptr, "%*d:%*2d:%*2d%*1[,.]%*3d --> %*d:%*2d:%*2d%*1[,.]%3d", &v) == 1)
             return AVPROBE_SCORE_MAX;
         num = atoi(ptr);
         ptr += strcspn(ptr, "\n") + 1;
     }
     return 0;
 }
 
 static int srt_read_header(AVFormatContext *s, AVFormatParameters *ap)
 {
     AVStream *st = av_new_stream(s, 0);
     if (!st)
         return -1;
     av_set_pts_info(st, 64, 1, 1000);
     st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
     st->codec->codec_id   = CODEC_ID_SRT;
     return 0;
 }
 
 static int64_t get_pts(const char *buf)
 {
     int i, v, hour, min, sec, hsec;
 
     for (i=0; i<2; i++) {
         if (sscanf(buf, "%d:%2d:%2d%*1[,.]%3d --> %*d:%*2d:%*2d%*1[,.]%3d",
                    &hour, &min, &sec, &hsec, &v) == 5) {
             min += 60*hour;
             sec += 60*min;
             return sec*1000+hsec;
         }
         buf += strcspn(buf, "\n") + 1;
     }
     return AV_NOPTS_VALUE;
 }
 
 static inline int is_eol(char c)
 {
     return c == '\r' || c == '\n';
 }
 
 static int srt_read_packet(AVFormatContext *s, AVPacket *pkt)
 {
     char buffer[2048], *ptr = buffer, *ptr2;

     int64_t pos = avio_tell(s->pb);

     int res = AVERROR_EOF;
 
     do {
         ptr2 = ptr;
         ptr += ff_get_line(s->pb, ptr, sizeof(buffer)+buffer-ptr);
     } while (!is_eol(*ptr2) && !url_feof(s->pb) && ptr-buffer<sizeof(buffer)-1);
 
     if (buffer[0] && !(res = av_new_packet(pkt, ptr-buffer))) {
         memcpy(pkt->data, buffer, pkt->size);
         pkt->flags |= AV_PKT_FLAG_KEY;
         pkt->pos = pos;
         pkt->pts = pkt->dts = get_pts(pkt->data);
     }
     return res;
 }
 

 AVInputFormat ff_srt_demuxer = {

     .name        = "srt",
     .long_name   = NULL_IF_CONFIG_SMALL("SubRip subtitle format"),
     .read_probe  = srt_probe,
     .read_header = srt_read_header,
     .read_packet = srt_read_packet,
     .flags       = AVFMT_GENERIC_INDEX,
 };