/* GStreamer tmplayer format subtitle parser

 * Copyright (C) 2006-2008 Tim-Philipp Müller <tim centricular net>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Library General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library 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

 * Library General Public License for more details.

 *

 * You should have received a copy of the GNU Library General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

#include "tmplayerparse.h"

#include <stdio.h>

#include <string.h>

/* From http://forum.doom9.org/archive/index.php/t-81059.html:

 * 

 * TMPlayer format, which comes in five varieties:

 * 

 * time-base 00:00:00:

 * 00:00:50:This is the Earth at a time|when the dinosaurs roamed...

 * 00:00:53:

 * 00:00:54:a lush and fertile planet.

 * 00:00:56:

 * 

 * time-base 0:00:00:

 * 0:00:50:This is the Earth at a time|when the dinosaurs roamed...

 * 0:00:53:

 * 0:00:54:a lush and fertile planet.

 * 0:00:56:

 * 

 * time-base 00:00:00=

 * 00:00:50=This is the Earth at a time|when the dinosaurs roamed...

 * 00:00:53=

 * 00:00:54=a lush and fertile planet.

 * 00:00:56=

 * 

 * time-base 0:00:00=

 * 0:00:50=This is the Earth at a time|when the dinosaurs roamed...

 * 0:00:53=

 * 0:00:54=a lush and fertile planet.

 * 0:00:56=

 * 

 * and multiline time-base 00:00:00,1=

 * 00:00:50,1=This is the Earth at a time

 * 00:00:50,2=when the dinosaurs roamed...

 * 00:00:53,1=

 * 00:00:54,1=a lush and fertile planet.

 * 00:00:56,1=

 *

 * --------------------------------------------------------------------------

 *

 * And another variety (which is 'time-base 0:00:00:' but without empty lines):

 *

 * 00:00:01:This is the Earth at a time|when the dinosaurs roamed...

 * 00:00:03:a lush and fertile planet.

 * 00:00:06:More text here

 * 00:00:12:Yet another line

 *

 */

static gchar *

tmplayer_process_buffer (ParserState * state)

{

  gchar *ret;

  ret = g_strndup (state->buf->str, state->buf->len);

  g_strdelimit (ret, "|", '\n');

  g_string_truncate (state->buf, 0);

  return ret;

}

static gchar *

tmplayer_parse_line (ParserState * state, const gchar * line, guint line_num)

{

  GstClockTime ts = GST_CLOCK_TIME_NONE;

  const gchar *text_start = NULL;

  gchar *ret = NULL;

  gchar divc = '\0';

  guint h, m, s, l = 1;

  if (sscanf (line, "%u:%02u:%02u,%u%c", &h, &m, &s, &l, &divc) == 5 &&

      (divc == '=')) {

    GST_LOG ("multiline format %u %u %u %u", h, m, s, l);

    ts = GST_SECOND * ((((h * 60) + m) * 60) + s);

    text_start = strchr (line, '=');

  } else if (sscanf (line, "%u:%02u:%02u%c", &h, &m, &s, &divc) == 4 &&

      (divc == '=' || divc == ':')) {

    GST_LOG ("single line format %u %u %u %u %c", h, m, s, l, divc);

    ts = GST_SECOND * ((((h * 60) + m) * 60) + s);

    text_start = strchr (line + 6, divc);

  } else if (line[0] == '\0' && state->buf->len > 0 &&

      GST_CLOCK_TIME_IS_VALID (state->start_time)) {

    /* if we get an empty line (could be the end of the file, but doesn't have

     * to be), just push whatever is still in the buffer without a duration */

    GST_LOG ("empty line, and there's still text in the buffer");

    ret = tmplayer_process_buffer (state);

    state->duration = GST_CLOCK_TIME_NONE;

    return ret;

  } else {

    GST_WARNING ("failed to parse line: '%s'", line);

    return NULL;

  }

  /* if this is a line without text, or the first line in a multiline file,

   * process and return the data in the buffer, which is the previous line(s) */

  if (text_start == NULL || text_start[1] == '\0' ||

      (l == 1 && state->buf->len > 0)) {

    if (GST_CLOCK_TIME_IS_VALID (state->start_time) &&

        state->start_time < ts && line_num > 0) {

      ret = tmplayer_process_buffer (state);

      state->duration = ts - state->start_time;

      /* ..and append current line's text (if there is any) for the next round.

       * We don't have to store ts as pending_start_time, since we deduce the

       * durations from the start times anyway, so as long as the parser just

       * forwards state->start_time by duration after it pushes the line we

       * are about to return it will all be good. */

      g_string_append (state->buf, text_start + 1);

    } else if (line_num > 0) {

      GST_WARNING ("end of subtitle unit but no valid start time?!");

    }

  } else {

    if (l > 1)

      g_string_append_c (state->buf, '\n');

    g_string_append (state->buf, text_start + 1);

    state->start_time = ts;

  }

  GST_LOG ("returning: '%s'", GST_STR_NULL (ret));

  return ret;

}

gchar *

parse_tmplayer (ParserState * state, const gchar * line)

{

  gchar *ret;

  /* GST_LOG ("Parsing: %s", line); */

  ret = tmplayer_parse_line (state, line, state->state);

  ++state->state;

  return ret;

}