/**
  * Embed the stylesheets' content
  * 
  * @param array $matches The matches of the regular expression
  * 
  * @return string The <style> tag
  */
 private static function replaceStylesheet($matches)
 {
     $src = $matches[1];
     $orig_src = $src;
     $src = preg_replace('/(\\?.*)$/', '', $src);
     $stylesheet = self::getFileContents($src);
     self::$_stylesheet_path = dirname($src);
     // @import
     $re = "/\\@import\\s+(?:url\\()?[\"']?([^\"\\'\\)]+)[\"']?\\)?;/i";
     $stylesheet = preg_replace_callback($re, array('self', 'replaceStylesheetImport'), $stylesheet);
     // url(foo)
     $re = "/url\\([\"']?([^\"\\'\\)]+)[\"']?\\)?/i";
     $stylesheet = preg_replace_callback($re, array('self', 'replaceStylesheetUrl'), $stylesheet);
     if (self::$_path) {
         return '<link rel="stylesheet" href="' . self::getEmbedURL($orig_src, $stylesheet, "css") . '" >';
     } else {
         return '<style type="text/css">' . $stylesheet . '</style>';
     }
 }