<?php
/*
Plugin Name: wp-syntax
Plugin URI: http://www.mcgearygroup.com
Description: Syntax highlighting using <a href="http://qbnz.com/highlighter/">Geshi</a> supporting a wide range of popular languages.
Author: Ryan McGeary
Version: 0.1-dev
Author URI: http://www.mcgearygroup.com
*/

#
#  Copyright (c) 2007 Ryan McGeary
#
#  This file is part of WP-Syntax.
#
#  WP-Syntax is free software; you can redistribute it and/or modify it under
#  the terms of the GNU General Public License as published by the Free
#  Software Foundation; either version 2 of the License, or (at your option)
#  any later version.
#
#  WP-Syntax 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 General Public License for more
#  details.
#
#  You should have received a copy of the GNU General Public License along
#  with WP-Syntax; if not, write to the Free Software Foundation, Inc., 59
#  Temple Place, Suite 330, Boston, MA 02111-1307 USA
#

include_once("geshi/geshi.php");

function wp_syntax_code_trim($code)
{
    // special ltrim b/c leading whitespace matters on 1st line of content
    $code = preg_replace("/^\s*\n/siU", "", $code);
    $code = rtrim($code);
    return $code;
}

function wp_syntax_highlight($matches)
{
    $language = strtolower(trim($matches[1]));
    $line = trim($matches[2]);
    $code = wp_syntax_code_trim($matches[3]);

    $geshi = new GeSHi($code, $language);

    // geshi styling.
#    $geshi->enable_classes(false);
#    $geshi->set_header_type(GESHI_HEADER_DIV);
#    $geshi->set_tab_width(2); // keeps code narrow
#    $geshi->enable_line_numbers(GESHI_FANCY_LINE_NUMBERS);

// count line breaks
// $lines = count(explode("\n", $code))

    return 
        '<div class="wp_syntax_code">'
        . $geshi->parse_code()
        . "</div>";
}

function wp_syntax_filter($content)
{
    return preg_replace_callback(
        "/<pre(?:lang=\"([\w-]+)\"|line=\"(\d+)\"|\s)+>(.*)<\/pre>/siU",
        "wp_syntax_highlight",
        $content
    );
}

// We generally want this to run before other filters; hence, a priority of 4
// was chosen.  The lower the number, the higher the priority.  10 is the
// default.  The textile plugin runs at 6.
add_filter('the_content', 'wp_syntax_filter', -1);
add_filter('the_excerpt', 'wp_syntax_filter', 1);
add_filter('comment_text', 'wp_syntax_filter', 1);

?>