AutoLinkText.php

public function autoLinkText($text)
{
	// a more readably-formatted version of the pattern is on http://daringfireball.net/2010/07/improved_regex_for_matching_urls
	$pattern  = '/((https?):\/\/)?([\da-z\.-]+\.[a-z\.]+)([\/\w \.-]+)*\/?/i';
	
	$callback = function($matches) {
		$url = array_shift($matches);
	
		if (is_null(parse_url($url, PHP_URL_SCHEME))) {
			$url = 'http://' . $url;                
		}

	    	$text = parse_url($url, PHP_URL_HOST) . parse_url($url, PHP_URL_PATH);
	    	$text = preg_replace("/^www./", "", $text);
	
		return sprintf('<a rel="nofollow" href="%s">%s</a>', $url, $text);
	};
	
	return preg_replace_callback($pattern, $callback, $text);
}