CakePHP: Don't refer to the same page (again)

AppController.php

class Appcontroler extends Controller {
  	public function referer($default = null, $local = false)
	  {
	  	$referer = $this->request->session()->read('Session.referer');
		if($default === null && $referer) {
			return $referer;
  		}
	  	return parent::referer($default, $local);
	  }

	public function beforeFilter(Event $event)
	{
		$referer = $this->request->referer(true);

		$here = $this->request->here;
		if (strpos($here, $this->request->base) === 0) {
			$here = substr($here, strlen($this->request->base));
			if ($here[0] !== '/') {
				$here = '/' . $here;
			}
		}

		if($referer != $here) {
			$this->request->session()->write('Session.referer', $referer);
		}
		return parent::beforeFilter($event);
	}
}