Parse Textile

if (!function_exists('parse_textile')) {
 
   function parse_textile($content, $safe_tags = '<a>, <b>, <i>, <u>, <blockquote>, <code>') {
 
      $content = ' ' . trim($content) . ' ';
 
      $modifiers = Array('\*\*'=>'b', '\__'=>'i', '\*'=>'strong', '\_'=>'em', '\-'=>'del', '\?\?'=>'cite', '%'=>'span', '\+'=>'ins', '\^'=>'sup', '\~'=>'sub', '@'=>'code');
 
      $content = strip_tags($content, $safe_tags);
 
      $content = ereg_replace('([[:space:]])"[[:<:]](.*)[[:>:]]"([[:space:]])', '\1&#8220;\2&#8221;\3', $content);
 
      $content = ereg_replace('([)([[:alnum:]]){1,5}(])', '<sup><a href="#fn\1">\1</a></sup>', $content);
 
      $content = ereg_replace('(<p>)(fn([[:alnum:]]){1,}. )([[:alnum:][:punct:][:space:]]+)(<\/p>)', '<p id="fn\3">\4</p>', $content);
 
      $content = str_replace(Array('--', '...', ' x ', '(TM)', '(R)', '(C)'), Array('&#8212;', '&#8230;', ' &#215; ', '&#8482;', '&#174;', '&#169;'), $content);
 
      while (list($key, $value) = @each($modifiers)) {
         $content = ereg_replace('([[:space:]])' . $key . '([[:alnum:]\(\)\*_-~\\+\\^!?\.<\\/>]{1,}([[:alnum:][:space:]\(\)\*_-~\\+\\^!?\.<\\/>"]+)?)' . $key, '\1<' . $value . '>\2</' . $value . '>', $content);
      }
 
      $content = ereg_replace('([[:alnum:]]+)(\()+([[:alnum:][:space:]]+)(\))', '<acronym title="\3">\1</acronym>', $content);
 
      $content = ereg_replace('([[:space:]])((http://)[[:alnum:][:punct:]]+)([[:space:]])?', '\1<a href="\2" rel="nofollow">\2</a>\4', $content);
 
      $content = str_replace("\n", "<br />\n", trim($content));
 
      return $content;
 
   }
 
}