/*
  * 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
  * SubViewer subtitle decoder
  * @see https://en.wikipedia.org/wiki/SubViewer
  */
 
 #include "avcodec.h"
 #include "ass.h"
 #include "libavutil/bprint.h"
 
 static int subviewer_event_to_ass(AVBPrint *buf, const char *p)
 {
     while (*p) {
         if (!strncmp(p, "[br]", 4)) {
             av_bprintf(buf, "\\N");
             p += 4;
         } else {
             if (p[0] == '\n' && p[1])
                 av_bprintf(buf, "\\N");

             else if (*p != '\n' && *p != '\r')

                 av_bprint_chars(buf, *p, 1);
             p++;
         }
     }
 
     return 0;
 }
 
 static int subviewer_decode_frame(AVCodecContext *avctx,
                                   void *data, int *got_sub_ptr, AVPacket *avpkt)
 {

     int ret = 0;

     AVSubtitle *sub = data;
     const char *ptr = avpkt->data;
     AVBPrint buf;
 
     av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);
     // note: no need to rescale pts & duration since they are in the same
     // timebase as ASS (1/100)
     if (ptr && avpkt->size > 0 && !subviewer_event_to_ass(&buf, ptr))

         ret = ff_ass_add_rect_bprint(sub, &buf, avpkt->pts, avpkt->duration);

     av_bprint_finalize(&buf, NULL);

     if (ret < 0)
         return ret;
     *got_sub_ptr = sub->num_rects > 0;

     return avpkt->size;
 }
 
 AVCodec ff_subviewer_decoder = {
     .name           = "subviewer",
     .long_name      = NULL_IF_CONFIG_SMALL("SubViewer subtitle"),
     .type           = AVMEDIA_TYPE_SUBTITLE,

     .id             = AV_CODEC_ID_SUBVIEWER,

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