Simple Wordpress plugin that link hashtags in posts to wp-tags

wphashtags.php

<?php
/*
Plugin Name: WpHashTags
Plugin URI: http://duperrific.com/
Description: Links twitter-style #hashtags into wordpress tags. Does not check if the tag exists tho.
Author: Armando Sosa
Version: 0.1
Author URI: http://armandososa.com/
*/

class WpHashTags{
	
	var $stripHashes = false;
	
	function hashIt($content, $stripHashes = null){
		if ($stripHashes) {
			$this->stripHashes = $stripHashes;			
		}
		// I use the ampersand to catch entities and later discard them
		// if somebody knows a more efficient way to do it in code, please tell me
		$pattern = "/(&?#[^\s|^,]+(\s[^\#|^\s]+#)?)/"; 
		$content = preg_replace_callback($pattern,array(&$this,'replaceCallback'),$content);
		return $content;
	}

	function replaceCallback($matches){
		$match = $matches[0];
		// just in case we matched an html entity, we discard it.
		if (strpos($match,'&') === 0) {
			return $match;
		}
		
		$tag = str_replace('#','',$match);		
		if ($this->stripHashes) {
			$match = $tag;
		}
		$tag = strtolower(str_replace(' ','-',$tag));
		$hashtag = $match;
		$link = $this->getLink($tag);
		return "<a href='$link'>$hashtag</a>";
	}	
	
	function getLink( $tag ) {
		global $wp_rewrite;
		$taglink = $wp_rewrite->get_tag_permastruct();
		if ( empty( $taglink ) ) {
			$file = get_option( 'home' ) . '/';
			$taglink = $file . '?tag=' . $tag;
		} else {
			$taglink = str_replace( '%tag%', $tag, $taglink );
			$taglink = get_option( 'home' ) . user_trailingslashit( $taglink, 'category' );
		}
		return $taglink;
	}
	
}

function wp_hash_tags($content){
	$o = new WpHashTags;
	return $o->hashIt($content);
}

add_action('the_content','wp_hash_tags');


?>