/*

  * SSA/ASS common functions

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

 #include "libavutil/avassert.h"

 #include "libavutil/avstring.h"

 #include "libavutil/bprint.h"

 #include "libavutil/common.h"

 int ff_ass_subtitle_header(AVCodecContext *avctx,
                            const char *font, int font_size,
                            int color, int back_color,
                            int bold, int italic, int underline,
                            int alignment)
 {

     avctx->subtitle_header = av_asprintf(

              "[Script Info]\r\n"

              "; Script generated by FFmpeg/Lavc%s\r\n"

              "ScriptType: v4.00+\r\n"

              "PlayResX: 384\r\n"
              "PlayResY: 288\r\n"

              "\r\n"
              "[V4+ Styles]\r\n"

 
              /* ASSv4 header */
              "Format: Name, "
              "Fontname, Fontsize, "
              "PrimaryColour, SecondaryColour, OutlineColour, BackColour, "
              "Bold, Italic, Underline, StrikeOut, "
              "ScaleX, ScaleY, "
              "Spacing, Angle, "
              "BorderStyle, Outline, Shadow, "
              "Alignment, MarginL, MarginR, MarginV, "
              "Encoding\r\n"
 
              "Style: "
              "Default,"             /* Name */
              "%s,%d,"               /* Font{name,size} */
              "&H%x,&H%x,&H%x,&H%x," /* {Primary,Secondary,Outline,Back}Colour */
              "%d,%d,%d,0,"          /* Bold, Italic, Underline, StrikeOut */
              "100,100,"             /* Scale{X,Y} */
              "0,0,"                 /* Spacing, Angle */
              "1,1,0,"               /* BorderStyle, Outline, Shadow */
              "%d,10,10,10,"         /* Alignment, Margin[LRV] */
              "0\r\n"                /* Encoding */
 

              "\r\n"
              "[Events]\r\n"

              "Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text\r\n",

              !(avctx->flags & CODEC_FLAG_BITEXACT) ? AV_STRINGIFY(LIBAVCODEC_VERSION) : "",

              font, font_size, color, color, back_color, back_color,
              -bold, -italic, -underline, alignment);
 
     if (!avctx->subtitle_header)
         return AVERROR(ENOMEM);
     avctx->subtitle_header_size = strlen(avctx->subtitle_header);
     return 0;
 }
 
 int ff_ass_subtitle_header_default(AVCodecContext *avctx)
 {
     return ff_ass_subtitle_header(avctx, ASS_DEFAULT_FONT,

                                ASS_DEFAULT_FONT_SIZE,
                                ASS_DEFAULT_COLOR,
                                ASS_DEFAULT_BACK_COLOR,
                                ASS_DEFAULT_BOLD,
                                ASS_DEFAULT_ITALIC,
                                ASS_DEFAULT_UNDERLINE,
                                ASS_DEFAULT_ALIGNMENT);

 }
 

 static void insert_ts(AVBPrint *buf, int ts)

 {

     if (ts == -1) {
         av_bprintf(buf, "9:59:59.99,");
     } else {
         int h, m, s;
 
         h = ts/360000;  ts -= 360000*h;
         m = ts/  6000;  ts -=   6000*m;
         s = ts/   100;  ts -=    100*s;
         av_bprintf(buf, "%d:%02d:%02d.%02d,", h, m, s, ts);
     }

 }
 

 int ff_ass_bprint_dialog(AVBPrint *buf, const char *dialog,
                          int ts_start, int duration, int raw)

 {

     int dlen;

     if (!raw || raw == 2) {
         long int layer = 0;
 
         if (raw == 2) {
             /* skip ReadOrder */
             dialog = strchr(dialog, ',');
             if (!dialog)
                 return AVERROR_INVALIDDATA;
             dialog++;
 
             /* extract Layer or Marked */
             layer = strtol(dialog, (char**)&dialog, 10);
             if (*dialog != ',')
                 return AVERROR_INVALIDDATA;
             dialog++;
         }

         av_bprintf(buf, "Dialogue: %ld,", layer);
         insert_ts(buf, ts_start);
         insert_ts(buf, duration == -1 ? -1 : ts_start + duration);

         if (raw != 2)

             av_bprintf(buf, "Default,,0,0,0,,");

     }
 
     dlen = strcspn(dialog, "\n");
     dlen += dialog[dlen] == '\n';
 

     av_bprintf(buf, "%.*s", dlen, dialog);

     if (raw == 2)

         av_bprintf(buf, "\r\n");
 
     return dlen;
 }
 
 int ff_ass_add_rect(AVSubtitle *sub, const char *dialog,
                     int ts_start, int duration, int raw)
 {
     AVBPrint buf;
     int ret, dlen;
     AVSubtitleRect **rects;
 
     av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);

     if ((ret = ff_ass_bprint_dialog(&buf, dialog, ts_start, duration, raw)) < 0)
         goto err;
     dlen = ret;

     if (!av_bprint_is_complete(&buf))

         goto errnomem;

     rects = av_realloc(sub->rects, (sub->num_rects+1) * sizeof(*sub->rects));
     if (!rects)

         goto errnomem;

     sub->rects = rects;
     sub->end_display_time = FFMAX(sub->end_display_time, 10 * duration);
     rects[sub->num_rects]       = av_mallocz(sizeof(*rects[0]));
     rects[sub->num_rects]->type = SUBTITLE_ASS;

     ret = av_bprint_finalize(&buf, &rects[sub->num_rects]->ass);
     if (ret < 0)

         goto err;

     sub->num_rects++;
     return dlen;

 
 errnomem:
     ret = AVERROR(ENOMEM);
 err:
     av_bprint_finalize(&buf, NULL);
     return ret;

 }

 int ff_ass_add_rect_bprint(AVSubtitle *sub, AVBPrint *buf,

                            int ts_start, int duration)

 {

     av_bprintf(buf, "\r\n");

     if (!av_bprint_is_complete(buf))
         return AVERROR(ENOMEM);

     return ff_ass_add_rect(sub, buf->str, ts_start, duration, 0);

 }
 

 void ff_ass_bprint_text_event(AVBPrint *buf, const char *p, int size,
                              const char *linebreaks, int keep_ass_markup)
 {
     const char *p_end = p + size;
 
     for (; p < p_end && *p; p++) {
 
         /* forced custom line breaks, not accounted as "normal" EOL */
         if (linebreaks && strchr(linebreaks, *p)) {
             av_bprintf(buf, "\\N");
 
         /* standard ASS escaping so random characters don't get mis-interpreted
          * as ASS */
         } else if (!keep_ass_markup && strchr("{}\\", *p)) {
             av_bprintf(buf, "\\%c", *p);
 
         /* some packets might end abruptly (no \0 at the end, like for example
          * in some cases of demuxing from a classic video container), some
          * might be terminated with \n or \r\n which we have to remove (for
          * consistency with those who haven't), and we also have to deal with
          * evil cases such as \r at the end of the buffer (and no \0 terminated
          * character) */
         } else if (p[0] == '\n') {
             /* some stuff left so we can insert a line break */
             if (p < p_end - 1)
                 av_bprintf(buf, "\\N");
         } else if (p[0] == '\r' && p < p_end - 1 && p[1] == '\n') {
             /* \r followed by a \n, we can skip it. We don't insert the \N yet
              * because we don't know if it is followed by more text */
             continue;
 
         /* finally, a sane character */
         } else {
             av_bprint_chars(buf, *p, 1);
         }
     }
 }