public static function add_js_file($file, $index = -1) {

        if (!file_exists(FS_ROOT.$file)) {
            Throw new Exception('Tried to add Javascript file that doesn\'t exist');
        }

        if ($index != -1) {
            for ($x = count(self::$js_includes); $x > $index + 1; $x --) {
                self::$js_includes[$x] = self::$js_includes[$x - 1];
            }
            self::$js_includes[$index] = $file;
        } else {
            self::$js_includes[] = $file;
        }

        global $_FirePHP; $_FirePHP->info('jiffy', 'JS File Added');

    }