/*

 * 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

 * RealText subtitle decoder

 * @see http://service.real.com/help/library/guides/ProductionGuide/prodguide/htmfiles/realtext.htm

 */

#include "avcodec.h"

#include "ass.h"

#include "codec_internal.h"

#include "libavutil/avstring.h"

#include "libavutil/bprint.h"

static int rt_event_to_ass(AVBPrint *buf, const char *p)

{

    int prev_chr_is_space = 1;

    while (*p) {

        if (*p != '<') {

            if (!av_isspace(*p))

                av_bprint_chars(buf, *p, 1);

            else if (!prev_chr_is_space)

                av_bprint_chars(buf, ' ', 1);

            prev_chr_is_space = av_isspace(*p);

        } else {

            const char *end = strchr(p, '>');

            if (!end)

                break;

            if (!av_strncasecmp(p, "<br/>", 5) ||

                !av_strncasecmp(p, "<br>",  4)) {

                av_bprintf(buf, "\\N");

            }

            p = end;

        }

        p++;

    }

    return 0;

}

static int realtext_decode_frame(AVCodecContext *avctx, AVSubtitle *sub,

                                 int *got_sub_ptr, const AVPacket *avpkt)

{

    int ret = 0;

    const char *ptr = avpkt->data;

    FFASSDecoderContext *s = avctx->priv_data;

    AVBPrint buf;

    av_bprint_init(&buf, 0, 4096);

    if (ptr && avpkt->size > 0 && !rt_event_to_ass(&buf, ptr))

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

    av_bprint_finalize(&buf, NULL);

    if (ret < 0)

        return ret;

    *got_sub_ptr = sub->num_rects > 0;

    return avpkt->size;

}

const FFCodec ff_realtext_decoder = {

    .p.name         = "realtext",

    CODEC_LONG_NAME("RealText subtitle"),

    .p.type         = AVMEDIA_TYPE_SUBTITLE,

    .p.id           = AV_CODEC_ID_REALTEXT,

    FF_CODEC_DECODE_SUB_CB(realtext_decode_frame),

    .init           = ff_ass_subtitle_header_default,

    .flush          = ff_ass_decoder_flush,

    .priv_data_size = sizeof(FFASSDecoderContext),

};