create AuthComponent with basic functionality

controllers/components/AuthComponent.inc

@@ -0,0 +1,80 @@
+<?php
+
+	/**
+	 * The Legend of Z
+	 *
+	 * @author	Oliver Hanraths <oliver.hanraths@uni-duesseldorf.de>
+	 * @copyright	2014 Heinrich-Heine-Universität Düsseldorf
+	 * @license	http://www.gnu.org/licenses/gpl.html
+	 * @link	https://bitbucket.org/coderkun/the-legend-of-z
+	 */
+	
+	namespace hhu\z\controllers\components;
+	
+	
+	/**
+	 * Component to handle authentication and authorization
+	 * 
+	 * @author	Oliver Hanraths <oliver.hanraths@uni-duesseldorf.de>
+	 */
+	class AuthComponent extends \nre\core\Component
+	{
+		/**
+		 * Key to save a user-ID as
+		 * 
+		 * @var string
+		 */
+		const KEY_USER_ID = 'user_id';
+		
+		
+		
+		
+		/**
+		 * Construct a new Auth-component.
+		 */
+		public function __construct()
+		{
+			// Start session
+			if(session_id() === '') {
+				session_start();
+				session_regenerate_id(true);
+			}
+		}
+		
+		
+		
+		
+		/**
+		 * Set the ID of the user that is currently logged in.
+		 * 
+		 * @param	int	$userId	ID of the currently logged in user
+		 */
+		public function setUserId($userId)
+		{
+			if(is_null($userId)) {
+				unset($_SESSION[self::KEY_USER_ID]);
+			}
+			else {
+				$_SESSION[self::KEY_USER_ID] = $userId;
+			}
+		}
+		
+		
+		/**
+		 * Get the ID of the user that is currently logged in.
+		 * 
+		 * @return	int	ID of the currently logged in user
+		 */
+		public function getUserId()
+		{
+			if(array_key_exists(self::KEY_USER_ID, $_SESSION)) {
+				return $_SESSION[self::KEY_USER_ID];
+			}
+		
+			
+			return null;
+		}
+	
+	}
+
+?>