protected function getClient($redirecturl = '') {
		// keep only one instance during a session
		if (is_object($this->google)) {
			return $this->google;
		}
		if ($redirecturl == '') {
			$redirecturl = $this->redirecturl;
		} else {
			$this->redirecturl = $redirecturl;
		}
		
		$client = new \Google_Client();
		$client->setApplicationName($this->options['application_name']);
		$client->setClientId($this->options['client_id']);
		$client->setClientSecret($this->options['client_secret']);
		$client->setRedirectUri($redirecturl);
		$client->setDeveloperKey($this->options['api_key']);
		$client->setScopes(array('https://www.googleapis.com/auth/userinfo.profile','https://www.googleapis.com/auth/userinfo.email'));
		
		$this->google = $client;
		
		return $client;
	}