Index: branches/5.2.x/core/kernel/application.php
===================================================================
diff -u -N -r15252 -r15287
--- branches/5.2.x/core/kernel/application.php	(.../application.php)	(revision 15252)
+++ branches/5.2.x/core/kernel/application.php	(.../application.php)	(revision 15287)
@@ -1,6 +1,6 @@
 <?php
 /**
-* @version	$Id: application.php 15252 2012-03-30 17:49:37Z alex $
+* @version	$Id: application.php 15287 2012-04-11 08:50:20Z alex $
 * @package	In-Portal
 * @copyright	Copyright (C) 1997 - 2009 Intechnic. All rights reserved.
 * @license      GNU/GPL
@@ -743,6 +743,7 @@
 		$this->registerClass('kHookManager', KERNEL_PATH . '/managers/hook_manager.php');
 		$this->registerClass('kScheduledTaskManager', KERNEL_PATH . '/managers/scheduled_task_manager.php');
 		$this->registerClass('kRequestManager', KERNEL_PATH . '/managers/request_manager.php');
+		$this->registerClass('kSubscriptionManager', KERNEL_PATH . '/managers/subscription_manager.php');
 
 		$this->registerClass('kUrlManager', KERNEL_PATH . '/managers/url_manager.php');
 		$this->registerClass('kUrlProcessor', KERNEL_PATH . '/managers/url_processor.php');
Index: branches/5.2.x/core/kernel/managers/subscription_manager.php
===================================================================
diff -u -N
--- branches/5.2.x/core/kernel/managers/subscription_manager.php	(revision 0)
+++ branches/5.2.x/core/kernel/managers/subscription_manager.php	(revision 15287)
@@ -0,0 +1,204 @@
+<?php
+/**
+ * @version	$Id: subscription_manager.php 15287 2012-04-11 08:50:20Z alex $
+ * @package	In-Portal
+ * @copyright	Copyright (C) 1997 - 2012 Intechnic. All rights reserved.
+ * @license	  GNU/GPL
+ * In-Portal is Open Source software.
+ * This means that this software may have been modified pursuant
+ * the GNU General Public License, and as distributed it includes
+ * or is derivative of works licensed under the GNU General Public License
+ * or other free or open source software licenses.
+ * See http://www.in-portal.org/license for copyright notices and details.
+ */
+
+defined('FULL_PATH') or die('restricted access!');
+
+class kSubscriptionManager extends kBase {
+
+	/**
+	 * List of subscriptions (instances of kSubcriptionItem objects)
+	 *
+	 * @var Array
+	 * @access protected
+	 */
+	protected $subscriptions = Array ();
+
+	/**
+	 * Adds set of fields, that uniquely identifies subscription
+	 *
+	 * @param Array $fields
+	 * @return void
+	 */
+	public function add($fields)
+	{
+		$this->subscriptions[] = new kSubscriptionItem($fields);
+	}
+
+	/**
+	 * Detects if current user is subscribed to new posts in given topic
+	 *
+	 * @return bool
+	 * @access public
+	 */
+	public function subscribed()
+	{
+		foreach ($this->subscriptions as $subscription) {
+			if ( !$subscription->getSubscription()->isLoaded() ) {
+				/* @var $subscription kSubscriptionItem */
+
+				return false;
+			}
+		}
+
+		return true;
+	}
+
+	/**
+	 * Subscribes current user to new posts in a given topic
+	 *
+	 * @return bool
+	 * @access public
+	 */
+	public function subscribe()
+	{
+		foreach ($this->subscriptions as $subscription) {
+			if ( !$subscription->subscribe() ) {
+				/* @var $subscription kSubscriptionItem */
+
+				return false;
+			}
+		}
+
+		return true;
+	}
+
+	/**
+	 * Unsubscribes current user from reciving e-mails about new posts in a gvein topic
+	 *
+	 * @return bool
+	 * @access public
+	 */
+	public function unsubscribe()
+	{
+		foreach ($this->subscriptions as $subscription) {
+			if ( !$subscription->unsubscribe() ) {
+				/* @var $subscription kSubscriptionItem */
+
+				return false;
+			}
+		}
+
+		return true;
+	}
+
+	/**
+	 * Returns e-mail event id or throws an exception, when such event not found
+	 *
+	 * @param string $email_event_name
+	 * @param int $type
+	 * @return string
+	 * @throws Exception
+	 * @access public
+	 */
+	public function getEmailEventId($email_event_name, $type = EmailEvent::EVENT_TYPE_FRONTEND)
+	{
+		$sql = 'SELECT EventId
+				FROM ' . TABLE_PREFIX . 'EmailEvents
+				WHERE Event = ' . $this->Conn->qstr($email_event_name) . ' AND Type = ' . $type;
+		$id = $this->Conn->GetOne($sql);
+
+		if ( !$id ) {
+			throw new Exception('E-mail event "' . $email_event_name . '" not found');
+		}
+
+		return $id;
+	}
+}
+
+
+class kSubscriptionItem extends kBase {
+
+	/**
+	 * Fields set, that uniquely identifies subscription
+	 *
+	 * @var Array
+	 * @access protected
+	 */
+	protected $fields = Array ();
+
+	/**
+	 * Creates new subscription item
+	 *
+	 * @param Array $fields
+	 * @access public
+	 */
+	public function __construct($fields)
+	{
+		parent::__construct();
+
+		$this->fields = $fields;
+	}
+
+	/**
+	 * Returns user subscription
+	 *
+	 * @param bool $reload
+	 * @return kBase|kDBItem
+	 * @access public
+	 */
+	public function getSubscription($reload = false)
+	{
+		$special = kUtil::crc32(serialize($this->fields));
+
+		$subscription = $this->Application->recallObject('system-event-subscription.' . $special, null, Array ('skip_autoload' => true));
+		/* @var $subscription kDBItem */
+
+		if ( !$subscription->isLoaded() || $reload ) {
+			$subscription->Load($this->fields);
+		}
+
+		return $subscription;
+	}
+
+	/**
+	 * Subscribes user
+	 *
+	 * @return bool
+	 * @access public
+	 */
+	public function subscribe()
+	{
+		$subscription = $this->getSubscription();
+
+		if ( $subscription->isLoaded() ) {
+			return true;
+		}
+
+		$subscription->SetDBFieldsFromHash($this->fields);
+
+		return $subscription->Create();
+	}
+
+	/**
+	 * Unsubscribes user
+	 *
+	 * @return bool
+	 * @access public
+	 */
+	public function unsubscribe()
+	{
+		$subscription = $this->getSubscription();
+
+		if ( !$subscription->isLoaded() ) {
+			return true;
+		}
+
+		$temp_handler = $this->Application->recallObject($subscription->getPrefixSpecial() . '_TempHandler', 'kTempTablesHandler');
+		/* @var $temp_handler kTempTablesHandler */
+
+		$temp_handler->DeleteItems($subscription->Prefix, $subscription->Special, Array ($subscription->GetID()));
+
+		return true;
+	}
+}
\ No newline at end of file