<?php

/*
Plugin Name: WP-HnConvert
Version: 0.1
Plugin URI: http://blog.7to3.net/web/2007/06/02/wordpress-hn-convert
Description: Convert heading tag's level in Body or Excerpt. For example, h1 to h2 or h3 to h2.
Author: Shuhei Kagawa
Author URI: http://www.7to3.net/
Update:
*/

function the_hn_converted_content($delta = 0, $more_link_text = '(more...)', $stripteaser = 0, $more_file = '') {
	$content = get_the_content($more_link_text, $stripteaser, $more_file);
	$content = apply_filters('the_content', $content);
	$content = str_replace(']]>', ']]&gt;', $content);
	
	$GLOBALS['hn_delta'] = $delta;
	$converted = preg_replace_callback("/<h([1-6])(.*?>.*?)<\/h([1-6])/s", 'hn_convert', $content);
	echo $converted;
}

function hn_convert($matches) {
	if ($matches[1] != $matches[3]) {
		return '<h' . $matches[1] . $matches[2] . '</h' . $matches[3];
	} else {
		$level = $matches[1] + $GLOBALS['hn_delta'];
		if ($level > 6) {
			$level = 6;
		} else if ($level < 1) {
			$level = 1;
		}
		return '<h' . $level . $matches[2] . '</h' . $level;
	}
}

?>