/*
  * SSA/ASS encoder
  * 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 <string.h>
 

 #include "avcodec.h"

 #include "ass_split.h"
 #include "ass.h"

 #include "libavutil/avstring.h"

 #include "libavutil/internal.h"
 #include "libavutil/mem.h"

 typedef struct {
     int id; ///< current event id, ReadOrder field
 } ASSEncodeContext;
 

 static av_cold int ass_encode_init(AVCodecContext *avctx)
 {

     avctx->extradata = av_malloc(avctx->subtitle_header_size + 1);

     if (!avctx->extradata)
         return AVERROR(ENOMEM);
     memcpy(avctx->extradata, avctx->subtitle_header, avctx->subtitle_header_size);
     avctx->extradata_size = avctx->subtitle_header_size;

     avctx->extradata[avctx->extradata_size] = 0;

     return 0;
 }
 
 static int ass_encode_frame(AVCodecContext *avctx,

                             unsigned char *buf, int bufsize,
                             const AVSubtitle *sub)

 {

     ASSEncodeContext *s = avctx->priv_data;

     int i, len, total_len = 0;
 
     for (i=0; i<sub->num_rects; i++) {

         char ass_line[2048];
         const char *ass = sub->rects[i]->ass;
 

         if (sub->rects[i]->type != SUBTITLE_ASS) {
             av_log(avctx, AV_LOG_ERROR, "Only SUBTITLE_ASS type supported.\n");
             return -1;
         }
 

         if (strncmp(ass, "Dialogue: ", 10)) {
             av_log(avctx, AV_LOG_ERROR, "AVSubtitle rectangle ass \"%s\""
                    " does not look like a SSA markup\n", ass);
             return AVERROR_INVALIDDATA;
         }
 
         if (avctx->codec->id == AV_CODEC_ID_ASS) {
             long int layer;
             char *p;
 
             if (i > 0) {
                 av_log(avctx, AV_LOG_ERROR, "ASS encoder supports only one "
                        "ASS rectangle field.\n");
                 return AVERROR_INVALIDDATA;
             }
 
             ass += 10; // skip "Dialogue: "
             /* parse Layer field. If it's a Marked field, the content
              * will be "Marked=N" instead of the layer num, so we will
              * have layer=0, which is fine. */
             layer = strtol(ass, &p, 10);
             if (*p) p += strcspn(p, ",") + 1; // skip layer or marked
             if (*p) p += strcspn(p, ",") + 1; // skip start timestamp
             if (*p) p += strcspn(p, ",") + 1; // skip end timestamp
             snprintf(ass_line, sizeof(ass_line), "%d,%ld,%s", ++s->id, layer, p);
             ass_line[strcspn(ass_line, "\r\n")] = 0;
             ass = ass_line;
         }
         len = av_strlcpy(buf+total_len, ass, bufsize-total_len);

 
         if (len > bufsize-total_len-1) {
             av_log(avctx, AV_LOG_ERROR, "Buffer too small for ASS event.\n");
             return -1;
         }
 
         total_len += len;
     }
 
     return total_len;
 }
 

 #if CONFIG_SSA_ENCODER
 AVCodec ff_ssa_encoder = {
     .name         = "ssa",

     .long_name    = NULL_IF_CONFIG_SMALL("SSA (SubStation Alpha) subtitle"),

     .type         = AVMEDIA_TYPE_SUBTITLE,

     .id           = AV_CODEC_ID_SSA,

     .init         = ass_encode_init,

     .encode_sub   = ass_encode_frame,

     .priv_data_size = sizeof(ASSEncodeContext),
 };
 #endif
 
 #if CONFIG_ASS_ENCODER
 AVCodec ff_ass_encoder = {
     .name         = "ass",
     .long_name    = NULL_IF_CONFIG_SMALL("ASS (Advanced SubStation Alpha) subtitle"),
     .type         = AVMEDIA_TYPE_SUBTITLE,
     .id           = AV_CODEC_ID_ASS,
     .init         = ass_encode_init,
     .encode_sub   = ass_encode_frame,
     .priv_data_size = sizeof(ASSEncodeContext),

 };

 #endif