1 files changed, 318 insertions, 768 deletions
diff --git a/engine/lib/group.php b/engine/lib/group.php
index 0a218b6f1..6ded8a825 100644
--- a/engine/lib/group.php
+++ b/engine/lib/group.php
@@ -1,791 +1,341 @@
 <?php
-	/**
-	 * Elgg Groups.
-	 * Groups contain other entities, or rather act as a placeholder for other entities to mark any given container
-	 * as their container.
-	 * 
-	 * @package Elgg
-	 * @subpackage Core
-	 * @license http://www.gnu.org/licenses/old-licenses/gpl-2.0.html GNU Public License version 2
-	 * @author Curverider Ltd
-	 * @copyright Curverider Ltd 2008
-	 * @link http://elgg.org/
-	 */
-
-	/**
-	 * @class ElggGroup Class representing a container for other elgg entities.
-	 * @author Curverider Ltd
-	 */
-	class ElggGroup extends ElggEntity
-		implements Friendable
-	{
-		protected function initialise_attributes()
-		{
-			parent::initialise_attributes();
-			
-			$this->attributes['type'] = "group";
-			$this->attributes['name'] = "";
-			$this->attributes['description'] = "";
-			$this->attributes['tables_split'] = 2;
-		}
-		
-		/**
-		 * Construct a new user entity, optionally from a given id value.
-		 *
-		 * @param mixed $guid If an int, load that GUID. 
-		 * 	If a db row then will attempt to load the rest of the data.
-		 * @throws Exception if there was a problem creating the user. 
-		 */
-		function __construct($guid = null) 
-		{			
-			$this->initialise_attributes();
-			
-			if (!empty($guid))
-			{
-				// Is $guid is a DB row - either a entity row, or a user table row.
-				if ($guid instanceof stdClass) {					
-					// Load the rest
-					if (!$this->load($guid->guid))
-						throw new IOException(sprintf(elgg_echo('IOException:FailedToLoadGUID'), get_class(), $guid->guid)); 
-				}
-						
-				// Is $guid is an ElggGroup? Use a copy constructor
-				else if ($guid instanceof ElggGroup)
-				{					
-					 foreach ($guid->attributes as $key => $value)
-					 	$this->attributes[$key] = $value;
-				}
-				
-				// Is this is an ElggEntity but not an ElggGroup = ERROR!
-				else if ($guid instanceof ElggEntity)
-					throw new InvalidParameterException(elgg_echo('InvalidParameterException:NonElggGroup'));
-										
-				// We assume if we have got this far, $guid is an int
-				else if (is_numeric($guid)) {					
-					if (!$this->load($guid)) IOException(sprintf(elgg_echo('IOException:FailedToLoadGUID'), get_class(), $guid));
-				}
-				
-				else
-					throw new InvalidParameterException(elgg_echo('InvalidParameterException:UnrecognisedValue'));
-			}
-		}
-		
-		/**
-		 * Add an ElggObject to this group.
-		 *
-		 * @param ElggObject $object The object.
-		 * @return bool
-		 */
-		public function addObjectToGroup(ElggObject $object)
-		{
-			return add_object_to_group($this->getGUID(), $object->getGUID());
-		}
-		
-		/**
-		 * Remove an object from the containing group.
-		 *
-		 * @param int $guid The guid of the object.
-		 * @return bool
-		 */
-		public function removeObjectFromGroup($guid)
-		{
-			return remove_object_from_group($this->getGUID(), $guid);
-		}
-		
-		public function get($name) {
-			
-			if ($name == 'username') {
-				return 'group:' . $this->getGUID();
-			}
-			return parent::get($name);
-			
-		}
-		
-	/**
-	 * Start friendable compatibility block:
-	 * 
-	 * 	public function addFriend($friend_guid);
-		public function removeFriend($friend_guid);
-		public function isFriend();
-		public function isFriendsWith($user_guid);
-		public function isFriendOf($user_guid);
-		public function getFriends($subtype = "", $limit = 10, $offset = 0);
-		public function getFriendsOf($subtype = "", $limit = 10, $offset = 0);
-		public function getObjects($subtype="", $limit = 10, $offset = 0);
-		public function getFriendsObjects($subtype = "", $limit = 10, $offset = 0);
-		public function countObjects($subtype = "");
-	 */
-		
-		/**
-		 * For compatibility with Friendable
-		 */
-		public function addFriend($friend_guid) {
-			return $this->join(get_entity($friend_guid));
-		}
-		
-		/**
-		 * For compatibility with Friendable
-		 */
-		public function removeFriend($friend_guid) {
-			return $this->leave(get_entity($friend_guid));
-		}
-
-		/**
-		 * For compatibility with Friendable
-		 */
-		public function isFriend() {
-			return $this->isMember();
-		}
-		
-		/**
-		 * For compatibility with Friendable
-		 */
-		public function isFriendsWith($user_guid) {
-			return $this->isMember($user_guid);
-		}
-		
-		/**
-		 * For compatibility with Friendable
-		 */
-		public function isFriendOf($user_guid) {
-			return $this->isMember($user_guid);
-		}
-		
-		/**
-		 * For compatibility with Friendable
-		 */
-		public function getFriends($subtype = "", $limit = 10, $offset = 0) { 
-			return get_group_members($this->getGUID(), $limit, $offset); 
-		}
-		
-		/**
-		 * For compatibility with Friendable
-		 */
-		public function getFriendsOf($subtype = "", $limit = 10, $offset = 0) { 
-			return get_group_members($this->getGUID(), $limit, $offset); 
-		}
-		
-		/**
-		 * Get objects contained in this group.
-		 *
-		 * @param string $subtype
-		 * @param int $limit
-		 * @param int $offset
-		 * @return mixed
-		 */
-		public function getObjects($subtype="", $limit = 10, $offset = 0) 
-		{
-			return get_objects_in_group($this->getGUID(), $subtype, 0, 0, "", $limit, $offset, false);
-		}
-		
-		/**
-		 * For compatibility with Friendable
-		 */
-		public function getFriendsObjects($subtype = "", $limit = 10, $offset = 0) {
-			return get_objects_in_group($this->getGUID(), $subtype, 0, 0, "", $limit, $offset, false);
-		}
-		
-		/**
-		 * For compatibility with Friendable
-		 */
-		public function countObjects($subtype = "") {
-			return get_objects_in_group($this->getGUID(), $subtype, 0, 0, "", 10, 0, true);
-		}
-		
-	/**
-	 * End friendable compatibility block
-	 */
-		
-		/**
-		 * Get a list of group members.
-		 *
-		 * @param int $limit
-		 * @param int $offset
-		 * @return mixed
-		 */
-		public function getMembers($limit = 10, $offset = 0, $count = false)
-		{
-			return get_group_members($this->getGUID(), $limit, $offset, 0 , $count);
-		}
-
-		
-		
-		/**
-		 * Returns whether the current group is public membership or not.
-		 * @return bool
-		 */
-		public function isPublicMembership()
-		{
-			if ($this->membership == 2)
-				return true;
-			
-			return false;
-		}
-		
-		/**
-		 * Return whether a given user is a member of this group or not.
-		 *
-		 * @param ElggUser $user The user
-		 * @return bool
-		 */
-		public function isMember($user = 0)
-		{
-			if (!($user instanceof ElggUser)) $user = get_loggedin_user();
-			if (!($user instanceof ElggUser)) return false;
-			return is_group_member($this->getGUID(), $user->getGUID());
-		}
-		
-		/**
-		 * Join an elgg user to this group.
-		 *
-		 * @param ElggUser $user
-		 * @return bool
-		 */
-		public function join(ElggUser $user)
-		{
-			return join_group($this->getGUID(), $user->getGUID());
-		}
-		
-		/**
-		 * Remove a user from the group.
-		 *
-		 * @param ElggUser $user
-		 */
-		public function leave(ElggUser $user)
-		{
-			return leave_group($this->getGUID(), $user->getGUID());
-		}
-		
-		/**
-		 * Delete this group.
-		 */
-		public function delete() 
-		{ 
-			
-			if (!delete_group_entity($this->get('guid')))
-				return false;
-				
-			return parent::delete();
-				
-		}
-		
-		
-		/**
-		 * Override the load function.
-		 * This function will ensure that all data is loaded (were possible), so
-		 * if only part of the ElggGroup is loaded, it'll load the rest.
-		 * 
-		 * @param int $guid 
-		 */
-		protected function load($guid)
-		{			
-			// Test to see if we have the generic stuff
-			if (!parent::load($guid)) 
-				return false;
-
-			// Check the type
-			if ($this->attributes['type']!='group')
-				throw new InvalidClassException(sprintf(elgg_echo('InvalidClassException:NotValidElggStar'), $guid, get_class()));
-				
-			// Load missing data
-			$row = get_group_entity_as_row($guid);
-			if (($row) && (!$this->isFullyLoaded())) $this->attributes['tables_loaded'] ++;	// If $row isn't a cached copy then increment the counter
-			
-			// Now put these into the attributes array as core values
-			$objarray = (array) $row;
-			foreach($objarray as $key => $value) 
-				$this->attributes[$key] = $value;
-			
-			return true;
-		}
-		
-		/**
-		 * Override the save function.
-		 */
-		public function save()
-		{
-			// Save generic stuff
-			if (!parent::save())
-				return false;
-		
-			// Now save specific stuff
-			return create_group_entity($this->get('guid'), $this->get('name'), $this->get('description'));
-		}
-	}
+/**
+ * Elgg Groups.
+ * Groups contain other entities, or rather act as a placeholder for other entities to
+ * mark any given container as their container.
+ *
+ * @package Elgg.Core
+ * @subpackage DataModel.Group
+ */
 
-	/**
-	 * Get the group entity.
-	 *
-	 * @param int $guid
-	 */
-	function get_group_entity_as_row($guid)
-	{
-		global $CONFIG;
-		
-		$guid = (int)$guid;
-		
-		$row = retrieve_cached_entity_row($guid);
-		if ($row)
-		{
-			// We have already cached this object, so retrieve its value from the cache
-			if (isset($CONFIG->debug) && $CONFIG->debug)
-				error_log("** Retrieving sub part of GUID:$guid from cache");
-				
-			return $row;
-		}
-		else
-		{
-			// Object not cached, load it.
-			if (isset($CONFIG->debug) && $CONFIG->debug == true)
-				error_log("** Sub part of GUID:$guid loaded from DB");
-		
-			return get_data_row("SELECT * from {$CONFIG->dbprefix}groups_entity where guid=$guid");
-		}
-	}
+/**
+ * Get the group entity.
+ *
+ * @param int $guid GUID for a group
+ *
+ * @return array|false
+ * @access private
+ */
+function get_group_entity_as_row($guid) {
+	global $CONFIG;
+
+	$guid = (int)$guid;
+
+	return get_data_row("SELECT * from {$CONFIG->dbprefix}groups_entity where guid=$guid");
+}
+
+/**
+ * Create or update the entities table for a given group.
+ * Call create_entity first.
+ *
+ * @param int    $guid        GUID
+ * @param string $name        Name
+ * @param string $description Description
+ *
+ * @return bool
+ * @access private
+ */
+function create_group_entity($guid, $name, $description) {
+	global $CONFIG;
+
+	$guid = (int)$guid;
+	$name = sanitise_string($name);
+	$description = sanitise_string($description);
 
-	/**
-	 * Create or update the extras table for a given group.
-	 * Call create_entity first.
-	 * 
-	 * @param int $guid
-	 * @param string $name
-	 * @param string $description
-	 */
-	function create_group_entity($guid, $name, $description)
-	{
-		global $CONFIG;
-		
-		$guid = (int)$guid;
-		$name = sanitise_string($name);
-		$description = sanitise_string($description);
-		
-		$row = get_entity_as_row($guid);
-		
-		if ($row)
-		{
-			// Exists and you have access to it
-			if ($exists = get_data_row("SELECT guid from {$CONFIG->dbprefix}groups_entity WHERE guid = {$guid}")) {
-				$result = update_data("UPDATE {$CONFIG->dbprefix}groups_entity set name='$name', description='$description' where guid=$guid");
-				if ($result!=false)
-				{
-					// Update succeeded, continue
-					$entity = get_entity($guid);
-					if (trigger_elgg_event('update',$entity->type,$entity)) {
-						return $guid;
-					} else {
-						delete_entity($guid);
-					}
+	$row = get_entity_as_row($guid);
+
+	if ($row) {
+		// Exists and you have access to it
+		$exists = get_data_row("SELECT guid from {$CONFIG->dbprefix}groups_entity WHERE guid = {$guid}");
+		if ($exists) {
+			$query = "UPDATE {$CONFIG->dbprefix}groups_entity set"
+				. " name='$name', description='$description' where guid=$guid";
+			$result = update_data($query);
+			if ($result != false) {
+				// Update succeeded, continue
+				$entity = get_entity($guid);
+				if (elgg_trigger_event('update', $entity->type, $entity)) {
+					return $guid;
+				} else {
+					$entity->delete();
 				}
 			}
-			else
-			{
-				// Update failed, attempt an insert.
-				$result = insert_data("INSERT into {$CONFIG->dbprefix}groups_entity (guid, name, description) values ($guid, '$name','$description')");
-				if ($result!==false) {
-					$entity = get_entity($guid);
-					if (trigger_elgg_event('create',$entity->type,$entity)) {
-						return $guid;
-					} else {
-						delete_entity($guid);
-					}
+		} else {
+			// Update failed, attempt an insert.
+			$query = "INSERT into {$CONFIG->dbprefix}groups_entity"
+				. " (guid, name, description) values ($guid, '$name', '$description')";
+
+			$result = insert_data($query);
+			if ($result !== false) {
+				$entity = get_entity($guid);
+				if (elgg_trigger_event('create', $entity->type, $entity)) {
+					return $guid;
+				} else {
+					$entity->delete();
 				}
 			}
 		}
-		
+	}
+
+	return false;
+}
+
+/**
+ * Add an object to the given group.
+ *
+ * @param int $group_guid  The group to add the object to.
+ * @param int $object_guid The guid of the elgg object (must be ElggObject or a child thereof)
+ *
+ * @return bool
+ * @throws InvalidClassException
+ */
+function add_object_to_group($group_guid, $object_guid) {
+	$group_guid = (int)$group_guid;
+	$object_guid = (int)$object_guid;
+
+	$group = get_entity($group_guid);
+	$object = get_entity($object_guid);
+
+	if ((!$group) || (!$object)) {
 		return false;
 	}
-	
-	
-	/**
-	 * Delete a group's extra data.
-	 *
-	 * @param int $guid The guid of the group
-	 * @return bool
-	 */
-	function delete_group_entity($guid)
-	{
-		global $CONFIG;
-		
-		$guid = (int)$guid;
-		
-		$row = get_entity_as_row($guid);
-		
-		// Check to see if we have access and it exists
-		if ($row) 
-		{
-			// Delete any existing stuff
-			return delete_data("DELETE from {$CONFIG->dbprefix}groups_entity where guid=$guid");
-		}
-		
+
+	if (!($group instanceof ElggGroup)) {
+		$msg = elgg_echo('InvalidClassException:NotValidElggStar', array($group_guid, 'ElggGroup'));
+		throw new InvalidClassException($msg);
+	}
+
+	if (!($object instanceof ElggObject)) {
+		$msg = elgg_echo('InvalidClassException:NotValidElggStar', array($object_guid, 'ElggObject'));
+		throw new InvalidClassException($msg);
+	}
+
+	$object->container_guid = $group_guid;
+	return $object->save();
+}
+
+/**
+ * Remove an object from the given group.
+ *
+ * @param int $group_guid  The group to remove the object from
+ * @param int $object_guid The object to remove
+ *
+ * @return bool
+ * @throws InvalidClassException
+ */
+function remove_object_from_group($group_guid, $object_guid) {
+	$group_guid = (int)$group_guid;
+	$object_guid = (int)$object_guid;
+
+	$group = get_entity($group_guid);
+	$object = get_entity($object_guid);
+
+	if ((!$group) || (!$object)) {
 		return false;
 	}
-	
-	/**
-	 * Add an object to the given group.
-	 *
-	 * @param int $group_guid The group to add the object to.
-	 * @param int $object_guid The guid of the elgg object (must be ElggObject or a child thereof)
-	 * @return bool
-	 */
-	function add_object_to_group($group_guid, $object_guid)
-	{
-		$group_guid = (int)$group_guid;
-		$object_guid = (int)$object_guid;
-		
-		$group = get_entity($group_guid);
-		$object = get_entity($object_guid);
-		
-		if ((!$group) || (!$object)) return false;
-		
-		if (!($group instanceof ElggGroup))
-			throw new InvalidClassException(sprintf(elgg_echo('InvalidClassException:NotValidElggStar'), $group_guid, 'ElggGroup'));
-
-		if (!($object instanceof ElggObject))
-			throw new InvalidClassException(sprintf(elgg_echo('InvalidClassException:NotValidElggStar'), $object_guid, 'ElggObject'));
-
-		$object->container_guid = $group_guid;
-		return $object->save();
+
+	if (!($group instanceof ElggGroup)) {
+		$msg = elgg_echo('InvalidClassException:NotValidElggStar', array($group_guid, 'ElggGroup'));
+		throw new InvalidClassException($msg);
 	}
-	
-	/**
-	 * Remove an object from the given group.
-	 *
-	 * @param int $group_guid The group to remove the object from
-	 * @param int $object_guid The object to remove
-	 */
-	function remove_object_from_group($group_guid, $object_guid)
-	{
-		$group_guid = (int)$group_guid;
-		$object_guid = (int)$object_guid;
-		
-		$group = get_entity($group_guid);
-		$object = get_entity($object_guid);
-		
-		if ((!$group) || (!$object)) return false;
-		
-		if (!($group instanceof ElggGroup))
-			throw new InvalidClassException(sprintf(elgg_echo('InvalidClassException:NotValidElggStar'), $group_guid, 'ElggGroup'));
-
-		if (!($object instanceof ElggObject))
-			throw new InvalidClassException(sprintf(elgg_echo('InvalidClassException:NotValidElggStar'), $object_guid, 'ElggObject'));
-
-		$object->container_guid = $object->owner_guid;
-		return $object->save();
+
+	if (!($object instanceof ElggObject)) {
+		$msg = elgg_echo('InvalidClassException:NotValidElggStar', array($object_guid, 'ElggObject'));
+		throw new InvalidClassException($msg);
 	}
-	
-	/**
-	 * Return an array of objects in a given container.
-	 * @see get_entities()
-	 *
-	 * @param int $group_guid The container (defaults to current page owner)
-	 * @param string $subtype The subtype
-	 * @param int $owner_guid Owner
-	 * @param int $site_guid The site
-	 * @param string $order_by Order
-	 * @param unknown_type $limit Limit on number of elements to return, by default 10.
-	 * @param unknown_type $offset Where to start, by default 0.
-	 * @param unknown_type $count Whether to return the entities or a count of them.
-	 */
-	function get_objects_in_group($group_guid, $subtype = "", $owner_guid = 0, $site_guid = 0, $order_by = "", $limit = 10, $offset = 0, $count = false)
-	{
-		global $CONFIG;
-		
-		if ($subtype === false || $subtype === null || $subtype === 0)
-			return false;
-			
-		$subtype = get_subtype_id('object', $subtype);
-		
-		if ($order_by == "") $order_by = "e.time_created desc";
-		$order_by = sanitise_string($order_by);
-		$limit = (int)$limit;
-		$offset = (int)$offset;
-		$site_guid = (int) $site_guid;
-		if ($site_guid == 0)
-			$site_guid = $CONFIG->site_guid;
-		
-		$container_guid = (int)$group_guid;
-		if ($container_guid == 0)
-			$container_guid = page_owner();
-				
-		$where = array();
-		
-		$where[] = "e.type='object'";
-		if ($subtype!=="")
-			$where[] = "e.subtype=$subtype";
-		if ($owner_guid != "") {
-			if (!is_array($owner_guid)) {
-				$owner_guid = (int) $owner_guid;
-				$where[] = "e.container_guid = '$owner_guid'";
-			} else if (sizeof($owner_guid) > 0) {
-				// Cast every element to the owner_guid array to int
-				$owner_guid = array_map("sanitise_int", $owner_guid);
-				$owner_guid = implode(",",$owner_guid);
-				$where[] = "e.container_guid in ({$owner_guid})";
-			}
-		}
-		if ($site_guid > 0)
-			$where[] = "e.site_guid = {$site_guid}";
-
-		if ($container_guid > 0)
-			$where[] = "e.container_guid = {$container_guid}";
-			
-		if (!$count) {
-			$query = "SELECT * from {$CONFIG->dbprefix}entities e join {$CONFIG->dbprefix}objects_entity o on e.guid=o.guid where ";
-		} else {
-			$query = "SELECT count(e.guid) as total from {$CONFIG->dbprefix}entities e join {$CONFIG->dbprefix}objects_entity o on e.guid=o.guid where ";
-		}
-		foreach ($where as $w)
-			$query .= " $w and ";
-		$query .= get_access_sql_suffix('e'); // Add access controls
-		if (!$count) {
-			$query .= " order by $order_by";
-			if ($limit) $query .= " limit $offset, $limit"; // Add order and limit
-
-			$dt = get_data($query, "entity_row_to_elggstar");
-			return $dt;
-		} else {
-			$total = get_data_row($query);
-			return $total->total;
-		}
+
+	$object->container_guid = $object->owner_guid;
+	return $object->save();
+}
+
+/**
+ * Return a list of this group's members.
+ *
+ * @param int  $group_guid The ID of the container/group.
+ * @param int  $limit      The limit
+ * @param int  $offset     The offset
+ * @param int  $site_guid  The site
+ * @param bool $count      Return the users (false) or the count of them (true)
+ *
+ * @return mixed
+ */
+function get_group_members($group_guid, $limit = 10, $offset = 0, $site_guid = 0, $count = false) {
+
+	// in 1.7 0 means "not set."  rewrite to make sense.
+	if (!$site_guid) {
+		$site_guid = ELGG_ENTITIES_ANY_VALUE;
 	}
-	
-	/**
-	 * Get all the entities from metadata from a group.
-	 *
-	 * @param int $group_guid The ID of the group.
-	 * @param mixed $meta_name 
-	 * @param mixed $meta_value
-	 * @param string $entity_type The type of entity to look for, eg 'site' or 'object'
-	 * @param string $entity_subtype The subtype of the entity.
-	 * @param int $limit 
-	 * @param int $offset
-	 * @param string $order_by Optional ordering.
-	 * @param int $site_guid The site to get entities for. Leave as 0 (default) for the current site; -1 for all sites.
-	 * @param true|false $count If set to true, returns the total number of entities rather than a list. (Default: false)
-	 */
-	function get_entities_from_metadata_groups($group_guid, $meta_name, $meta_value = "", $entity_type = "", $entity_subtype = "", $owner_guid = 0, $limit = 10, $offset = 0, $order_by = "", $site_guid = 0, $count = false)
-	{
-		global $CONFIG;
-		
-		$meta_n = get_metastring_id($meta_name);
-		$meta_v = get_metastring_id($meta_value);
-			
-		$entity_type = sanitise_string($entity_type);
-		$entity_subtype = get_subtype_id($entity_type, $entity_subtype);
-		$limit = (int)$limit;
-		$offset = (int)$offset;
-		if ($order_by == "") $order_by = "e.time_created desc";
-		$order_by = sanitise_string($order_by);
-		$site_guid = (int) $site_guid;
-		if (is_array($owner_guid)) {
-			foreach($owner_guid as $key => $guid) {
-				$owner_guid[$key] = (int) $guid;
-			}
-		} else {
-			$owner_guid = (int) $owner_guid;
-		}
-		if ($site_guid == 0)
-			$site_guid = $CONFIG->site_guid;
-			
-		$container_guid = (int)$group_guid;
-		if ($container_guid == 0)
-			$container_guid = page_owner();
-			
-		//$access = get_access_list();
-			
-		$where = array();
-		
-		if ($entity_type!="")
-			$where[] = "e.type='$entity_type'";
-		if ($entity_subtype)
-			$where[] = "e.subtype=$entity_subtype";
-		if ($meta_name!="")
-			$where[] = "m.name_id='$meta_n'";
-		if ($meta_value!="")
-			$where[] = "m.value_id='$meta_v'";
-		if ($site_guid > 0)
-			$where[] = "e.site_guid = {$site_guid}";
-		if ($container_guid > 0)
-			$where[] = "e.container_guid = {$container_guid}";
-		if (is_array($owner_guid)) {
-			$where[] = "e.container_guid in (".implode(",",$owner_guid).")";
-		} else if ($owner_guid > 0)
-			$where[] = "e.container_guid = {$owner_guid}";
-		
-		if (!$count) {
-			$query = "SELECT distinct e.* "; 
-		} else {
-			$query = "SELECT count(e.guid) as total ";
-		}
-			
-		$query .= "from {$CONFIG->dbprefix}entities e JOIN {$CONFIG->dbprefix}metadata m on e.guid = m.entity_guid join {$CONFIG->dbprefix}objects_entity o on e.guid = o.guid where";
-		foreach ($where as $w)
-			$query .= " $w and ";
-		$query .= get_access_sql_suffix("e"); // Add access controls
-		
-		if (!$count) {
-			$query .= " order by $order_by limit $offset, $limit"; // Add order and limit
-			return get_data($query, "entity_row_to_elggstar");
-		} else {
-			if ($row = get_data_row($query))
-				return $row->total;
-		}
+
+	return elgg_get_entities_from_relationship(array(
+		'relationship' => 'member',
+		'relationship_guid' => $group_guid,
+		'inverse_relationship' => TRUE,
+		'type' => 'user',
+		'limit' => $limit,
+		'offset' => $offset,
+		'count' => $count,
+		'site_guid' => $site_guid
+	));
+}
+
+/**
+ * Return whether a given user is a member of the group or not.
+ *
+ * @param int $group_guid The group ID
+ * @param int $user_guid  The user guid
+ *
+ * @return bool
+ */
+function is_group_member($group_guid, $user_guid) {
+	$object = check_entity_relationship($user_guid, 'member', $group_guid);
+	if ($object) {
+		return true;
+	} else {
 		return false;
 	}
-	
-	/**
-	 * As get_entities_from_metadata_groups() but with multiple entities.
-	 *
-	 * @param int $group_guid The ID of the group.
-	 * @param array $meta_array Array of 'name' => 'value' pairs
-	 * @param string $entity_type The type of entity to look for, eg 'site' or 'object'
-	 * @param string $entity_subtype The subtype of the entity.
-	 * @param int $limit 
-	 * @param int $offset
-	 * @param string $order_by Optional ordering.
-	 * @param int $site_guid The site to get entities for. Leave as 0 (default) for the current site; -1 for all sites.
-	 * @param true|false $count If set to true, returns the total number of entities rather than a list. (Default: false)
-	 * @return int|array List of ElggEntities, or the total number if count is set to false
-	 */
-	function get_entities_from_metadata_groups_multi($group_guid, $meta_array, $entity_type = "", $entity_subtype = "", $owner_guid = 0, $limit = 10, $offset = 0, $order_by = "", $site_guid = 0, $count = false)
-	{
-		global $CONFIG;
-		
-		if (!is_array($meta_array) || sizeof($meta_array) == 0) {
-			return false;
-		}
-		
-		$where = array();
-		
-		$mindex = 1;
-		$join = "";
-		foreach($meta_array as $meta_name => $meta_value) {
-			$meta_n = get_metastring_id($meta_name);
-			$meta_v = get_metastring_id($meta_value);
-			$join .= " JOIN {$CONFIG->dbprefix}metadata m{$mindex} on e.guid = m{$mindex}.entity_guid join {$CONFIG->dbprefix}objects_entity o on e.guid = o.guid "; 
-			if ($meta_name!="")
-				$where[] = "m{$mindex}.name_id='$meta_n'";
-			if ($meta_value!="")
-				$where[] = "m{$mindex}.value_id='$meta_v'";
-			$mindex++;
-		}
-			
-		$entity_type = sanitise_string($entity_type);
-		$entity_subtype = get_subtype_id($entity_type, $entity_subtype);
-		$limit = (int)$limit;
-		$offset = (int)$offset;
-		if ($order_by == "") $order_by = "e.time_created desc";
-		$order_by = sanitise_string($order_by);
-		$owner_guid = (int) $owner_guid;
-		
-		$site_guid = (int) $site_guid;
-		if ($site_guid == 0)
-			$site_guid = $CONFIG->site_guid;
-			
-		//$access = get_access_list();
-		
-		if ($entity_type!="")
-			$where[] = "e.type = '{$entity_type}'";
-		if ($entity_subtype)
-			$where[] = "e.subtype = {$entity_subtype}";
-		if ($site_guid > 0)
-			$where[] = "e.site_guid = {$site_guid}";
-		if ($owner_guid > 0)
-			$where[] = "e.owner_guid = {$owner_guid}";
-		if ($container_guid > 0)
-			$where[] = "e.container_guid = {$container_guid}";
-		
-		if ($count) {
-			$query = "SELECT count(e.guid) as total ";
-		} else {
-			$query = "SELECT distinct e.* "; 
-		}
-			
-		$query .= " from {$CONFIG->dbprefix}entities e {$join} where";
-		foreach ($where as $w)
-			$query .= " $w and ";
-		$query .= get_access_sql_suffix("e"); // Add access controls
-		
-		if (!$count) {
-			$query .= " order by $order_by limit $offset, $limit"; // Add order and limit
-			return get_data($query, "entity_row_to_elggstar");
+}
+
+/**
+ * Join a user to a group.
+ *
+ * @param int $group_guid The group GUID.
+ * @param int $user_guid  The user GUID.
+ *
+ * @return bool
+ */
+function join_group($group_guid, $user_guid) {
+	$result = add_entity_relationship($user_guid, 'member', $group_guid);
+
+	if ($result) {
+		$params = array('group' => get_entity($group_guid), 'user' => get_entity($user_guid));
+		elgg_trigger_event('join', 'group', $params);
+	}
+
+	return $result;
+}
+
+/**
+ * Remove a user from a group.
+ *
+ * @param int $group_guid The group.
+ * @param int $user_guid  The user.
+ *
+ * @return bool
+ */
+function leave_group($group_guid, $user_guid) {
+	// event needs to be triggered while user is still member of group to have access to group acl
+	$params = array('group' => get_entity($group_guid), 'user' => get_entity($user_guid));
+
+	elgg_trigger_event('leave', 'group', $params);
+	$result = remove_entity_relationship($user_guid, 'member', $group_guid);
+	return $result;
+}
+
+/**
+ * Return all groups a user is a member of.
+ *
+ * @param int $user_guid GUID of user
+ *
+ * @return array|false
+ */
+function get_users_membership($user_guid) {
+	$options = array(
+		'type' => 'group',
+		'relationship' => 'member',
+		'relationship_guid' => $user_guid,
+		'inverse_relationship' => false,
+		'limit' => false,
+	);
+	return elgg_get_entities_from_relationship($options);
+}
+
+/**
+ * May the current user access item(s) on this page? If the page owner is a group,
+ * membership, visibility, and logged in status are taken into account.
+ *
+ * @param boolean $forward If set to true (default), will forward the page;
+ *                         if set to false, will return true or false.
+ *
+ * @return bool If $forward is set to false.
+ */
+function group_gatekeeper($forward = true) {
+
+	$page_owner_guid = elgg_get_page_owner_guid();
+	if (!$page_owner_guid) {
+		return true;
+	}
+	$visibility = ElggGroupItemVisibility::factory($page_owner_guid);
+
+	if (!$visibility->shouldHideItems) {
+		return true;
+	}
+	if ($forward) {
+		// only forward to group if user can see it
+		$group = get_entity($page_owner_guid);
+		$forward_url = $group ? $group->getURL() : '';
+
+		if (!elgg_is_logged_in()) {
+			$_SESSION['last_forward_from'] = current_page_url();
+			$forward_reason = 'login';
 		} else {
-			if ($count = get_data_row($query)) {
-				return $count->total;
-			}
+			$forward_reason = 'member';
 		}
-		return false;
-	}
-	
-	/**
-	 * Return a list of this group's members.
-	 * 
-	 * @param int $group_guid The ID of the container/group.
-	 * @param int $limit The limit
-	 * @param int $offset The offset
-	 * @param int $site_guid The site
-	 * @param bool $count Return the users (false) or the count of them (true)
-	 * @return mixed
-	 */
-	function get_group_members($group_guid, $limit = 10, $offset = 0, $site_guid = 0, $count = false)
-	{
-		return get_entities_from_relationship('member', $group_guid, true, 'user', '', 0, "", $limit, $offset, $count, $site_guid);
+
+		register_error(elgg_echo($visibility->reasonHidden));
+		forward($forward_url, $forward_reason);
 	}
-	
-	/**
-	 * Return whether a given user is a member of the group or not.
-	 * 
-	 * @param int $group_guid The group ID
-	 * @param int $user_guid The user guid
-	 * @return bool
-	 */
-	function is_group_member($group_guid, $user_guid)
-	{
-		return check_entity_relationship($user_guid, 'member', $group_guid);
+
+	return false;
+}
+
+/**
+ * Adds a group tool option
+ *
+ * @see remove_group_tool_option().
+ *
+ * @param string $name       Name of the group tool option
+ * @param string $label      Used for the group edit form
+ * @param bool   $default_on True if this option should be active by default
+ *
+ * @return void
+ * @since 1.5.0
+ */
+function add_group_tool_option($name, $label, $default_on = true) {
+	global $CONFIG;
+
+	if (!isset($CONFIG->group_tool_options)) {
+		$CONFIG->group_tool_options = array();
 	}
-	
-	/**
-	 * Join a user to a group.
-	 * 
-	 * @param int $group_guid The group.
-	 * @param int $user_guid The user.
-	 */
-	function join_group($group_guid, $user_guid)
-	{
-		trigger_elgg_event('join','group',array('group' => get_entity($group_guid), 'user' => get_entity($user_guid)));
-		return add_entity_relationship($user_guid, 'member', $group_guid);
+
+	$group_tool_option = new stdClass;
+
+	$group_tool_option->name = $name;
+	$group_tool_option->label = $label;
+	$group_tool_option->default_on = $default_on;
+
+	$CONFIG->group_tool_options[] = $group_tool_option;
+}
+
+/**
+ * Removes a group tool option based on name
+ *
+ * @see add_group_tool_option()
+ *
+ * @param string $name Name of the group tool option
+ *
+ * @return void
+ * @since 1.7.5
+ */
+function remove_group_tool_option($name) {
+	global $CONFIG;
+
+	if (!isset($CONFIG->group_tool_options)) {
+		return;
 	}
-	
-	/**
-	 * Remove a user from a group.
-	 * 
-	 * @param int $group_guid The group.
-	 * @param int $user_guid The user.
-	 */
-	function leave_group($group_guid, $user_guid)
-	{
-		trigger_elgg_event('leave','group',array('group' => get_entity($group_guid), 'user' => get_entity($user_guid)));
-		return remove_entity_relationship($user_guid, 'member', $group_guid);
+
+	foreach ($CONFIG->group_tool_options as $i => $option) {
+		if ($option->name == $name) {
+			unset($CONFIG->group_tool_options[$i]);
+		}
 	}
-	
-	/**
-	 * Return all groups a user is a member of.
-	 *
-	 * @param unknown_type $user_guid
-	 */
-	function get_users_membership($user_guid)
-	{
-		return get_entities_from_relationship('member', $user_guid, false);
-	}
-	
-	/**
-	 * Performs initialisation functions for groups
-	 *
-	 */
-	function group_init() {
-		register_entity_type('group','');
-	}
-	
-	register_elgg_event_handler('init','system','group_init');
-	
-?>
-\ No newline at end of file
+}