/*
  * Copyright (c) 2012 Clément Bœsch
  *
  * 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
  */
 
 /**
  * @file
  * RealText subtitle decoder
  * @see http://service.real.com/help/library/guides/ProductionGuide/prodguide/htmfiles/realtext.htm
  */
 
 #include "avcodec.h"
 #include "ass.h"
 #include "libavutil/avstring.h"
 #include "libavutil/bprint.h"
 
 static int rt_event_to_ass(AVBPrint *buf, const char *p)
 {
     int prev_chr_is_space = 1;
 
     while (*p) {
         if (*p != '<') {

             if (!av_isspace(*p))

                 av_bprint_chars(buf, *p, 1);
             else if (!prev_chr_is_space)
                 av_bprint_chars(buf, ' ', 1);

             prev_chr_is_space = av_isspace(*p);

         } else {
             const char *end = strchr(p, '>');
             if (!end)
                 break;
             if (!av_strncasecmp(p, "<br/>", 5) ||
                 !av_strncasecmp(p, "<br>",  4)) {
                 av_bprintf(buf, "\\N");
             }
             p = end;
         }
         p++;
     }
     av_bprintf(buf, "\r\n");
     return 0;
 }
 
 static int realtext_decode_frame(AVCodecContext *avctx,
                                  void *data, int *got_sub_ptr, AVPacket *avpkt)
 {
     AVSubtitle *sub = data;
     const char *ptr = avpkt->data;
     AVBPrint buf;
 
     av_bprint_init(&buf, 0, 4096);
     // note: no need to rescale pts & duration since they are in the same

     // timebase as ASS (1/100)

     if (ptr && avpkt->size > 0 && !rt_event_to_ass(&buf, ptr))
         ff_ass_add_rect(sub, buf.str, avpkt->pts, avpkt->duration, 0);
     *got_sub_ptr = sub->num_rects > 0;
     av_bprint_finalize(&buf, NULL);
     return avpkt->size;
 }
 
 AVCodec ff_realtext_decoder = {
     .name           = "realtext",
     .long_name      = NULL_IF_CONFIG_SMALL("RealText subtitle"),
     .type           = AVMEDIA_TYPE_SUBTITLE,

     .id             = AV_CODEC_ID_REALTEXT,

     .decode         = realtext_decode_frame,
     .init           = ff_ass_subtitle_header_default,
 };