/*
  * 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
  * JACOsub subtitle decoder
  * @see http://unicorn.us.com/jacosub/jscripts.html
  */
 
 #include <time.h>
 #include "ass.h"
 #include "jacosub.h"
 #include "libavutil/avstring.h"
 #include "libavutil/bprint.h"

 #include "libavutil/time_internal.h"

 
 #undef time
 
 static int insert_text(AVBPrint *dst, const char *in, const char *arg)
 {
     av_bprintf(dst, "%s", arg);
     return 0;
 }
 
 static int insert_datetime(AVBPrint *dst, const char *in, const char *arg)
 {
     char buf[16] = {0};
     time_t now = time(0);
     struct tm ltime;
 
     localtime_r(&now, &ltime);

     if (strftime(buf, sizeof(buf), arg, &ltime))
         av_bprintf(dst, "%s", buf);

     return 0;
 }
 
 static int insert_color(AVBPrint *dst, const char *in, const char *arg)
 {
     return 1; // skip id
 }
 
 static int insert_font(AVBPrint *dst, const char *in, const char *arg)
 {
     return 1; // skip id
 }
 
 static const struct {
     const char *from;
     const char *arg;
     int (*func)(AVBPrint *dst, const char *in, const char *arg);
 } ass_codes_map[] = {
     {"\\~", "~",        insert_text},       // tilde doesn't need escaping
     {"~",   "{\\h}",    insert_text},       // hard space
     {"\\n", "\\N",      insert_text},       // newline
     {"\\D", "%d %b %Y", insert_datetime},   // current date
     {"\\T", "%H:%M",    insert_datetime},   // current time
     {"\\N", "{\\r}",    insert_text},       // reset to default style
     {"\\I", "{\\i1}",   insert_text},       // italic on
     {"\\i", "{\\i0}",   insert_text},       // italic off
     {"\\B", "{\\b1}",   insert_text},       // bold on
     {"\\b", "{\\b0}",   insert_text},       // bold off
     {"\\U", "{\\u1}",   insert_text},       // underline on
     {"\\u", "{\\u0}",   insert_text},       // underline off
     {"\\C", "",         insert_color},      // TODO: color
     {"\\F", "",         insert_font},       // TODO: font
 };
 
 enum {
     ALIGN_VB = 1<<0, // vertical bottom, default
     ALIGN_VM = 1<<1, // vertical middle
     ALIGN_VT = 1<<2, // vertical top
     ALIGN_JC = 1<<3, // justify center, default
     ALIGN_JL = 1<<4, // justify left
     ALIGN_JR = 1<<5, // justify right
 };
 
 static void jacosub_to_ass(AVCodecContext *avctx, AVBPrint *dst, const char *src)
 {
     int i, valign = 0, halign = 0;
     char c = av_toupper(*src);
     char directives[128] = {0};
 
     /* extract the optional directives */
     if ((c >= 'A' && c <= 'Z') || c == '[') {
         char *p    = directives;
         char *pend = directives + sizeof(directives) - 1;
 
         do *p++ = av_toupper(*src++);
         while (*src && !jss_whitespace(*src) && p < pend);
         *p = 0;
         src = jss_skip_whitespace(src);
     }
 
     /* handle directives (TODO: handle more of them, and more reliably) */
     if      (strstr(directives, "VB")) valign = ALIGN_VB;
     else if (strstr(directives, "VM")) valign = ALIGN_VM;
     else if (strstr(directives, "VT")) valign = ALIGN_VT;
     if      (strstr(directives, "JC")) halign = ALIGN_JC;
     else if (strstr(directives, "JL")) halign = ALIGN_JL;
     else if (strstr(directives, "JR")) halign = ALIGN_JR;
     if (valign || halign) {
         if (!valign) valign = ALIGN_VB;
         if (!halign) halign = ALIGN_JC;
         switch (valign | halign) {
         case ALIGN_VB | ALIGN_JL: av_bprintf(dst, "{\\an1}"); break; // bottom left
         case ALIGN_VB | ALIGN_JC: av_bprintf(dst, "{\\an2}"); break; // bottom center
         case ALIGN_VB | ALIGN_JR: av_bprintf(dst, "{\\an3}"); break; // bottom right
         case ALIGN_VM | ALIGN_JL: av_bprintf(dst, "{\\an4}"); break; // middle left
         case ALIGN_VM | ALIGN_JC: av_bprintf(dst, "{\\an5}"); break; // middle center
         case ALIGN_VM | ALIGN_JR: av_bprintf(dst, "{\\an6}"); break; // middle right
         case ALIGN_VT | ALIGN_JL: av_bprintf(dst, "{\\an7}"); break; // top left
         case ALIGN_VT | ALIGN_JC: av_bprintf(dst, "{\\an8}"); break; // top center
         case ALIGN_VT | ALIGN_JR: av_bprintf(dst, "{\\an9}"); break; // top right
         }
     }
 
     /* process timed line */
     while (*src && *src != '\n') {
 
         /* text continue on the next line */
         if (src[0] == '\\' && src[1] == '\n') {
             src += 2;
             while (jss_whitespace(*src))
                 src++;
             continue;
         }
 
         /* special character codes */
         for (i = 0; i < FF_ARRAY_ELEMS(ass_codes_map); i++) {
             const char *from = ass_codes_map[i].from;
             const char *arg  = ass_codes_map[i].arg;
             size_t codemap_len = strlen(from);
 
             if (!strncmp(src, from, codemap_len)) {
                 src += codemap_len;
                 src += ass_codes_map[i].func(dst, src, arg);
                 break;
             }
         }
 
         /* simple char copy */
         if (i == FF_ARRAY_ELEMS(ass_codes_map))
             av_bprintf(dst, "%c", *src++);
     }
 }
 
 static int jacosub_decode_frame(AVCodecContext *avctx,
                                 void *data, int *got_sub_ptr, AVPacket *avpkt)
 {

     int ret;

     AVSubtitle *sub = data;
     const char *ptr = avpkt->data;

     FFASSDecoderContext *s = avctx->priv_data;

 
     if (avpkt->size <= 0)
         goto end;
 
     if (*ptr) {
         AVBPrint buffer;
 
         // skip timers
         ptr = jss_skip_whitespace(ptr);
         ptr = strchr(ptr, ' '); if (!ptr) goto end; ptr++;
         ptr = strchr(ptr, ' '); if (!ptr) goto end; ptr++;
 
         av_bprint_init(&buffer, JSS_MAX_LINESIZE, JSS_MAX_LINESIZE);
         jacosub_to_ass(avctx, &buffer, ptr);

         ret = ff_ass_add_rect(sub, buffer.str, s->readorder++, 0, NULL, NULL);

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

     }
 
 end:
     *got_sub_ptr = sub->num_rects > 0;
     return avpkt->size;
 }
 
 AVCodec ff_jacosub_decoder = {
     .name           = "jacosub",
     .long_name      = NULL_IF_CONFIG_SMALL("JACOsub subtitle"),
     .type           = AVMEDIA_TYPE_SUBTITLE,

     .id             = AV_CODEC_ID_JACOSUB,

     .init           = ff_ass_subtitle_header_default,
     .decode         = jacosub_decode_frame,

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

 };