/*
  * SubRip subtitle decoder
  * 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 "libavutil/avstring.h"

 #include "libavutil/common.h"

 #include "libavutil/intreadwrite.h"

 #include "libavutil/parseutils.h"

 #include "avcodec.h"
 #include "ass.h"

 #include "htmlsubtitles.h"

 static int srt_to_ass(AVCodecContext *avctx, AVBPrint *dst,

                        const char *in, int x1, int y1, int x2, int y2)

 {
     if (x1 >= 0 && y1 >= 0) {

         /* XXX: here we rescale coordinate assuming they are in DVD resolution
          * (720x480) since we don't have anything better */
 
         if (x2 >= 0 && y2 >= 0 && (x2 != x1 || y2 != y1) && x2 >= x1 && y2 >= y1) {
             /* text rectangle defined, write the text at the center of the rectangle */
             const int cx = x1 + (x2 - x1)/2;
             const int cy = y1 + (y2 - y1)/2;

             const int scaled_x = cx * (int64_t)ASS_DEFAULT_PLAYRESX / 720;
             const int scaled_y = cy * (int64_t)ASS_DEFAULT_PLAYRESY / 480;

             av_bprintf(dst, "{\\an5}{\\pos(%d,%d)}", scaled_x, scaled_y);
         } else {
             /* only the top left corner, assume the text starts in that corner */

             const int scaled_x = x1 * (int64_t)ASS_DEFAULT_PLAYRESX / 720;
             const int scaled_y = y1 * (int64_t)ASS_DEFAULT_PLAYRESY / 480;

             av_bprintf(dst, "{\\an1}{\\pos(%d,%d)}", scaled_x, scaled_y);
         }

     }
 

     return ff_htmlmarkup_to_ass(avctx, dst, in);

 }
 
 static int srt_decode_frame(AVCodecContext *avctx,
                             void *data, int *got_sub_ptr, AVPacket *avpkt)
 {
     AVSubtitle *sub = data;

     AVBPrint buffer;

     int x1 = -1, y1 = -1, x2 = -1, y2 = -1;

     int size, ret;

     const uint8_t *p = av_packet_get_side_data(avpkt, AV_PKT_DATA_SUBTITLE_POSITION, &size);

     FFASSDecoderContext *s = avctx->priv_data;

 
     if (p && size == 16) {
         x1 = AV_RL32(p     );
         y1 = AV_RL32(p +  4);
         x2 = AV_RL32(p +  8);
         y2 = AV_RL32(p + 12);
     }

 
     if (avpkt->size <= 0)
         return avpkt->size;
 

     av_bprint_init(&buffer, 0, AV_BPRINT_SIZE_UNLIMITED);
 

     ret = srt_to_ass(avctx, &buffer, avpkt->data, x1, y1, x2, y2);
     if (ret >= 0)
         ret = ff_ass_add_rect(sub, buffer.str, s->readorder++, 0, NULL, NULL);

     av_bprint_finalize(&buffer, NULL);
     if (ret < 0)
         return ret;

 
     *got_sub_ptr = sub->num_rects > 0;
     return avpkt->size;
 }
 

 #if CONFIG_SRT_DECODER

 /* deprecated decoder */

 AVCodec ff_srt_decoder = {

     .name         = "srt",

     .long_name    = NULL_IF_CONFIG_SMALL("SubRip subtitle"),

     .type         = AVMEDIA_TYPE_SUBTITLE,

     .id           = AV_CODEC_ID_SUBRIP,

     .init         = ff_ass_subtitle_header_default,
     .decode       = srt_decode_frame,

     .flush        = ff_ass_decoder_flush,
     .priv_data_size = sizeof(FFASSDecoderContext),

 };

 #endif
 
 #if CONFIG_SUBRIP_DECODER
 AVCodec ff_subrip_decoder = {
     .name         = "subrip",
     .long_name    = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
     .type         = AVMEDIA_TYPE_SUBTITLE,
     .id           = AV_CODEC_ID_SUBRIP,
     .init         = ff_ass_subtitle_header_default,
     .decode       = srt_decode_frame,

     .flush        = ff_ass_decoder_flush,
     .priv_data_size = sizeof(FFASSDecoderContext),

 };
 #endif