Converted line endings to unix.

git-svn-id: http://code.elgg.org/elgg/trunk@6957 36083f99-b078-4883-b0ff-0f9b5a30f544

1 files changed, 1348 insertions, 1348 deletions

diff --git a/engine/classes/ElggEntity.php b/engine/classes/ElggEntity.php
index f793f67c0..37722243c 100644
--- a/engine/classes/ElggEntity.php
+++ b/engine/classes/ElggEntity.php
@@ -1,1349 +1,1349 @@
-<?php

-/**

- * The parent class for all Elgg Entities.

- *

- * An ElggEntity is one of the basic data models in Elgg.  It is the primary

- * means of storing and retrieving data from the database.  An ElggEntity

- * represents one row of the entities table.

- *

- * The ElggEntity class handles CRUD operations for the entities table.

- * ElggEntity should always be extended by another class to handle CRUD

- * operations on the type-specific table.

- *

- * ElggEntity uses magic methods for get and set, so any property that isn't

- * declared will be assumed to be metadata and written to the database

- * as metadata on the object.  All children classes must declare which

- * properties are columns of the type table or they will be assumed

- * to be metadata.  See ElggObject::initialise_entities() for examples.

- *

- * Core supports 4 types of entities: ElggObject, ElggUser, ElggGroup, and

- * ElggSite.

- *

- * @tip Most plugin authors will want to extend the ElggObject class

- * instead of this class.

- *

- * @package Elgg.Core

- * @subpackage DataMode.Entities

- * @link http://docs.elgg.org/DataModel/ElggEntity

- */

-abstract class ElggEntity implements

-	Notable,    // Calendar interface

-	Locatable,  // Geocoding interface

-	Exportable, // Allow export of data

-	Importable, // Allow import of data

-	Loggable,	// Can events related to this object class be logged

-	Iterator,	// Override foreach behaviour

-	ArrayAccess // Override for array access

-{

-	/**

-	 * The main attributes of an entity.

-	 * Blank entries for all database fields should be created by the constructor.

-	 * Subclasses should add to this in their constructors.

-	 * Any field not appearing in this will be viewed as a

-	 */

-	protected $attributes;

-

-	/**

-	 * If set, overrides the value of getURL()

-	 */

-	protected $url_override;

-

-	/**

-	 * Icon override, overrides the value of getIcon().

-	 */

-	protected $icon_override;

-

-	/**

-	 * Holds metadata until entity is saved.  Once the entity is saved, metadata are written immediately to the database.

-	 */

-	protected $temp_metadata;

-

-	/**

-	 * Holds annotations until entity is saved.  Once the entity is saved, annotations are written immediately to the database.

-	 */

-	protected $temp_annotations;

-

-

-	/**

-	 * Volatile data structure for this object, allows for storage of data

-	 * in-memory that isn't sync'd back to the metadata table.

-	 */

-	protected $volatile;

-

-	/**

-	 * Initialise the attributes array.

-	 *

-	 * This is vital to distinguish between metadata and base parameters.

-	 *

-	 * @return void

-	 */

-	protected function initialise_attributes() {

-		initialise_entity_cache();

-

-		// Create attributes array if not already created

-		if (!is_array($this->attributes)) {

-			$this->attributes = array();

-		}

-		if (!is_array($this->temp_metadata)) {

-			$this->temp_metadata = array();

-		}

-		if (!is_array($this->temp_annotations)) {

-			$this->temp_annotations = array();

-		}

-		if (!is_array($this->volatile)) {

-			$this->volatile = array();

-		}

-

-		$this->attributes['guid'] = "";

-		$this->attributes['type'] = "";

-		$this->attributes['subtype'] = "";

-

-		$this->attributes['owner_guid'] = get_loggedin_userid();

-		$this->attributes['container_guid'] = get_loggedin_userid();

-

-		$this->attributes['site_guid'] = 0;

-		$this->attributes['access_id'] = ACCESS_PRIVATE;

-		$this->attributes['time_created'] = "";

-		$this->attributes['time_updated'] = "";

-		$this->attributes['last_action'] = '';

-		$this->attributes['enabled'] = "yes";

-

-		// There now follows a bit of a hack

-		/* Problem: To speed things up, some objects are split over several tables, this means that it requires

-		 * n number of database reads to fully populate an entity. This causes problems for caching and create events

-		 * since it is not possible to tell whether a subclassed entity is complete.

-		 * Solution: We have two counters, one 'tables_split' which tells whatever is interested how many tables

-		 * are going to need to be searched in order to fully populate this object, and 'tables_loaded' which is how

-		 * many have been loaded thus far.

-		 * If the two are the same then this object is complete.

-		 *

-		 * Use: isFullyLoaded() to check

-		 */

-		$this->attributes['tables_split'] = 1;

-		$this->attributes['tables_loaded'] = 0;

-	}

-

-	/**

-	 * Clone an entity

-	 *

-	 * Resets the guid so that the entity can be saved as a distinct entity from

-	 * the original. Creation time will be set when this new entity is saved.

-	 * The owner and container guids come from the original entity. The clone

-	 * method copies metadata but does not copy annotations or private settings.

-	 *

-	 * @note metadata will have its owner and access id set when the entity is saved

-	 * and it will be the same as that of the entity.

-	 */

-	public function __clone() {

-		$orig_entity = get_entity($this->guid);

-		if (!$orig_entity) {

-			elgg_log("Failed to clone entity with GUID $this->guid", "ERROR");

-			return;

-		}

-

-		$metadata_array = get_metadata_for_entity($this->guid);

-

-		$this->attributes['guid'] = "";

-

-		$this->attributes['subtype'] = $orig_entity->getSubtype();

-

-		// copy metadata over to new entity - slightly convoluted due to

-		// handling of metadata arrays

-		if (is_array($metadata_array)) {

-			// create list of metadata names

-			$metadata_names = array();

-			foreach ($metadata_array as $metadata) {

-				$metadata_names[] = $metadata['name'];

-			}

-			// arrays are stored with multiple enties per name

-			$metadata_names = array_unique($metadata_names);

-

-			// move the metadata over

-			foreach ($metadata_names as $name) {

-				$this->set($name, $orig_entity->$name);

-			}

-		}

-	}

-

-	/**

-	 * Return the value of a property.

-	 *

-	 * If $name is defined in $this->attributes that value is returned, otherwise it will

-	 * pull from the entity's metadata.

-	 *

-	 * Q: Why are we not using __get overload here?

-	 * A: Because overload operators cause problems during subclassing, so we put the code here and

-	 * create overloads in subclasses.

-	 * @todo What problems are these?

-	 *

-	 * @warning Subtype is returned as an id rather than the subtype string. Use getSubtype()

-	 * to get the subtype string.

-	 *

-	 * @param string $name

-	 * @return mixed Returns the value of a given value, or null.

-	 */

-	public function get($name) {

-		// See if its in our base attributes

-		if (isset($this->attributes[$name])) {

-			return $this->attributes[$name];

-		}

-

-		// No, so see if its in the meta data for this entity

-		$meta = $this->getMetaData($name);

-

-		// getMetaData returns NULL if $name is not found

-		return $meta;

-	}

-

-	/**

-	 * Sets the value of a property.

-	 *

-	 * If $name is defined in $this->attributes that value is set, otherwise it will

-	 * set the appropriate item of metadata.

-	 *

-	 * @warning It is important that your class populates $this->attributes with keys for all base attributes, anything

-	 * not in their gets set as METADATA.

-	 *

-	 * Q: Why are we not using __set overload here?

-	 * A: Because overload operators cause problems during subclassing, so we put the code here and

-	 * create overloads in subclasses.

-	 * @todo What problems?

-	 *

-	 * @param string $name

-	 * @param mixed $value

-	 */

-	public function set($name, $value) {

-		if (array_key_exists($name, $this->attributes)) {

-			// Certain properties should not be manually changed!

-			switch ($name) {

-				case 'guid':

-				case 'time_created':

-				case 'time_updated':

-				case 'last_action':

-					return FALSE;

-					break;

-				default:

-					$this->attributes[$name] = $value;

-					break;

-			}

-		} else {

-			return $this->setMetaData($name, $value);

-		}

-

-		return TRUE;

-	}

-

-	/**

-	 * Return the value of a piece of metadata.

-	 *

-	 * @param string $name

-	 * @return mixed The value, or NULL if not found.

-	 */

-	public function getMetaData($name) {

-		if ((int) ($this->guid) > 0) {

-			$md = get_metadata_byname($this->getGUID(), $name);

-		} else {

-			if (isset($this->temp_metadata[$name])) {

-				return $this->temp_metadata[$name];

-			}

-		}

-

-		if ($md && !is_array($md)) {

-			return $md->value;

-		} else if ($md && is_array($md)) {

-			return metadata_array_to_values($md);

-		}

-

-		return null;

-	}

-

-	/**

-	 * Return an attribute or a piece of metadata.

-	 *

-	 * @param string $name

-	 * @return mixed

-	 */

-	function __get($name) {

-		return $this->get($name);

-	}

-

-	/**

-	 * Set an attribute or a piece of metadata.

-	 *

-	 * @param string $name

-	 * @param mixed $value

-	 * @return mixed

-	 */

-	function __set($name, $value) {

-		return $this->set($name, $value);

-	}

-

-	/**

-	 * Test if property is set either as an attribute or metadata.

-	 *

-	 * @tip Use isset($entity->property)

-	 *

-	 * @param string $name The name of the attribute or metadata.

-	 * @return bool

-	 */

-	function __isset($name) {

-		return $this->$name !== NULL;

-	}

-

-	/**

-	 * Unset a property from metadata or attribute.

-	 *

-	 * @warning If you use this to unset an attribute, you must save the object!

-	 *

-	 * @param string $name The name of the attribute or metadata.

-	 */

-	function __unset($name) {

-		if (array_key_exists($name, $this->attributes)) {

-			$this->attributes[$name] = "";

-		}

-		else {

-			$this->clearMetaData($name);

-		}

-	}

-

-	/**

-	 * Set a piece of metadata.

-	 *

-	 * @tip Plugin authors should use the magic methods.

-	 *

-	 * @access private

-	 * @param string $name Name of the metadata

-	 * @param mixed $value Value of the metadata

-	 * @param string $value_type Types supported: integer and string. Will auto-identify if not set

-	 * @param bool $multiple (does not support associative arrays)

-	 * @return bool

-	 */

-	public function setMetaData($name, $value, $value_type = "", $multiple = false) {

-		if (is_array($value)) {

-			unset($this->temp_metadata[$name]);

-			remove_metadata($this->getGUID(), $name);

-			foreach ($value as $v) {

-				if ((int) $this->guid > 0) {

-					$multiple = true;

-					if (!create_metadata($this->getGUID(), $name, $v, $value_type,

-					$this->getOwner(), $this->getAccessID(), $multiple)) {

-						return false;

-					}

-				} else {

-					if (($multiple) && (isset($this->temp_metadata[$name]))) {

-						if (!is_array($this->temp_metadata[$name])) {

-							$tmp = $this->temp_metadata[$name];

-							$this->temp_metadata[$name] = array();

-							$this->temp_metadata[$name][] = $tmp;

-						}

-

-						$this->temp_metadata[$name][] = $value;

-					}

-					else {

-						$this->temp_metadata[$name] = $value;

-					}

-				}

-			}

-

-			return true;

-		} else {

-			unset($this->temp_metadata[$name]);

-			if ((int) $this->guid > 0) {

-				$result = create_metadata($this->getGUID(), $name, $value, $value_type, $this->getOwner(), $this->getAccessID(), $multiple);

-				return (bool)$result;

-			} else {

-				if (($multiple) && (isset($this->temp_metadata[$name]))) {

-					if (!is_array($this->temp_metadata[$name])) {

-						$tmp = $this->temp_metadata[$name];

-						$this->temp_metadata[$name] = array();

-						$this->temp_metadata[$name][] = $tmp;

-					}

-

-					$this->temp_metadata[$name][] = $value;

-				}

-				else {

-					$this->temp_metadata[$name] = $value;

-				}

-

-				return true;

-			}

-		}

-	}

-

-	/**

-	 * Remove metadata

-	 *

-	 * @warning Calling this with no or empty arguments will clear all metadata on the entity.

-	 * @param string The name of the metadata to clear

-	 * @return mixed The n

-	 */

-	public function clearMetaData($name = "") {

-		if (empty($name)) {

-			return clear_metadata($this->getGUID());

-		} else {

-			return remove_metadata($this->getGUID(), $name);

-		}

-	}

-

-

-	/**

-	 * Get a piece of volatile (non-persisted) data on this entity.

-	 *

-	 * @param string $name The name of the volatile data

-	 * @return mixed The value or NULL if not found.

-	 */

-	public function getVolatileData($name) {

-		if (!is_array($this->volatile)) {

-			$this->volatile = array();

-		}

-

-		if (array_key_exists($name, $this->volatile)) {

-			return $this->volatile[$name];

-		} else {

-			return NULL;

-		}

-	}

-

-

-	/**

-	 * Set a piece of volatile (non-persisted) data on this entity

-	 *

-	 * @param string $name

-	 * @param mixed $value

-	 */

-	public function setVolatileData($name, $value) {

-		if (!is_array($this->volatile)) {

-			$this->volatile = array();

-		}

-

-		$this->volatile[$name] = $value;

-	}

-

-

-	/**

-	 * Remove all relationships to and from this entity.

-	 *

-	 * @return true

-	 * @todo This should actually return if it worked.

-	 * @see ElggEntity::addRelationship()

-	 * @see ElggEntity::removeRelationship()

-	 */

-	public function clearRelationships() {

-		remove_entity_relationships($this->getGUID());

-		remove_entity_relationships($this->getGUID(), "", true);

-		return true;

-	}

-

-	/**

-	 * Add a relationship between this an another entity.

-	 *

-	 * @tip Read the relationship like "$guid is a $relationship of this entity."

-	 *

-	 * @param int $guid Entity to link to.

-	 * @param string $relationship The type of relationship.

-	 * @return bool

-	 * @see ElggEntity::removeRelationship()

-	 * @see ElggEntity::clearRelationships()

-	 */

-	public function addRelationship($guid, $relationship) {

-		return add_entity_relationship($this->getGUID(), $relationship, $guid);

-	}

-

-	/**

-	 * Remove a relationship

-	 *

-	 * @param int $guid

-	 * @param str $relationship

-	 * @return bool

-	 * @see ElggEntity::addRelationship()

-	 * @see ElggEntity::clearRelationships()

-	 */

-	public function removeRelationship($guid, $relationship) {

-		return remove_entity_relationship($this->getGUID(), $relationship, $guid);

-	}

-

-	/**

-	 * Adds a private setting to this entity.

-	 *

-	 * Private settings are similar to metadata but will not

-	 * be searched and there are fewer helper functions for them.

-	 *

-	 * @param $name

-	 * @param $value

-	 * @return bool

-	 * @link http://docs.elgg.org/DataModel/Entities/PrivateSettings

-	 */

-	function setPrivateSetting($name, $value) {

-		return set_private_setting($this->getGUID(), $name, $value);

-	}

-

-	/**

-	 * Returns a private setting value

-	 *

-	 * @param $name

-	 * @return mixed

-	 */

-	function getPrivateSetting($name) {

-		return get_private_setting($this->getGUID(), $name);

-	}

-

-	/**

-	 * Removes private setting

-	 *

-	 * @param $name

-	 * @return bool

-	 */

-	function removePrivateSetting($name) {

-		return remove_private_setting($this->getGUID(), $name);

-	}

-

-	/**

-	 * Adds an annotation to an entity.

-	 *

-	 * @warning By default, annotations are private.

-	 *

-	 * @param string $name

-	 * @param mixed $value

-	 * @param int $access_id

-	 * @param int $owner_id

-	 * @param string $vartype

-	 * @link http://docs.elgg.org/DataModel/Annotations

-	 */

-	function annotate($name, $value, $access_id = ACCESS_PRIVATE, $owner_id = 0, $vartype = "") {

-		if ((int) $this->guid > 0) {

-			return create_annotation($this->getGUID(), $name, $value, $vartype, $owner_id, $access_id);

-		} else {

-			$this->temp_annotations[$name] = $value;

-		}

-		return true;

-	}

-

-	/**

-	 * Returns an array of annotations.

-	 *

-	 * @param string $name

-	 * @param int $limit

-	 * @param int $offset

-	 * @param string $order asc or desc

-	 * @return array

-	 */

-	function getAnnotations($name, $limit = 50, $offset = 0, $order="asc") {

-		if ((int) ($this->guid) > 0) {

-			return get_annotations($this->getGUID(), "", "", $name, "", 0, $limit, $offset, $order);

-		} else {

-			return $this->temp_annotations[$name];

-		}

-	}

-

-	/**

-	 * Remove an annotation or all annotations for this entity.

-	 *

-	 * @warning Calling this method with no or an empty argument will remove all annotations on the entity.

-	 *

-	 * @param string $name

-	 * @return bool

-	 */

-	function clearAnnotations($name = "") {

-		return clear_annotations($this->getGUID(), $name);

-	}

-

-	/**

-	 * Count annotations.

-	 *

-	 * @param string $name The type of annotation.

-	 * @return int

-	 */

-	function countAnnotations($name = "") {

-		return count_annotations($this->getGUID(), "", "", $name);

-	}

-

-	/**

-	 * Get the average of an integer type annotation.

-	 *

-	 * @param string $name

-	 * @return int

-	 */

-	function getAnnotationsAvg($name) {

-		return get_annotations_avg($this->getGUID(), "", "", $name);

-	}

-

-	/**

-	 * Get the sum of integer type annotations of a given name.

-	 *

-	 * @param string $name

-	 * @return int

-	 */

-	function getAnnotationsSum($name) {

-		return get_annotations_sum($this->getGUID(), "", "", $name);

-	}

-

-	/**

-	 * Get the minimum of integer type annotations of given name.

-	 *

-	 * @param string $name

-	 * @return int

-	 */

-	function getAnnotationsMin($name) {

-		return get_annotations_min($this->getGUID(), "", "", $name);

-	}

-

-	/**

-	 * Get the maximum of integer type annotations of a given name.

-	 *

-	 * @param string $name

-	 * @return int

-	 */

-	function getAnnotationsMax($name) {

-		return get_annotations_max($this->getGUID(), "", "", $name);

-	}

-

-	/**

-	 * Gets an array of entities with a relationship to this entity.

-	 *

-	 * @param string $relationship Relationship type (eg "friends")

-	 * @param true|false $inverse Is this an inverse relationship?

-	 * @param int $limit Number of elements to return

-	 * @param int $offset Indexing offset

-	 * @return array|false An array of entities or false on failure

-	 */

-	function getEntitiesFromRelationship($relationship, $inverse = false, $limit = 50, $offset = 0) {

-		return elgg_get_entities_from_relationship(array(

-			'relationship' => $relationship,

-			'relationship_guid' => $this->getGUID(),

-			'inverse_relationship' => $inverse,

-			'limit' => $limit,

-			'offset' => $offset

-		));

-	}

-

-	/**

-	 * Gets the number of of entities from a specific relationship type

-	 *

-	 * @param string $relationship Relationship type (eg "friends")

-	 * @param bool $inverse_relationship

-	 * @return int|false The number of entities or false on failure

-	 */

-	function countEntitiesFromRelationship($relationship, $inverse_relationship = FALSE) {

-		return elgg_get_entities_from_relationship(array(

-			'relationship' => $relationship,

-			'relationship_guid' => $this->getGUID(),

-			'inverse_relationship' => $inverse_relationship,

-			'count' => TRUE

-		));

-	}

-

-	/**

-	 * Can a user edit this entity.

-	 *

-	 * @param int $user_guid The user GUID, optionally (defaults to the currently logged in user)

-	 * @return true|false

-	 */

-	function canEdit($user_guid = 0) {

-		return can_edit_entity($this->getGUID(), $user_guid);

-	}

-

-	/**

-	 * Can a user edit metadata on this entity

-	 *

-	 * @param ElggMetadata $metadata The piece of metadata to specifically check

-	 * @param int $user_guid The user GUID, optionally (defaults to the currently logged in user)

-	 * @return true|false

-	 */

-	function canEditMetadata($metadata = null, $user_guid = 0) {

-		return can_edit_entity_metadata($this->getGUID(), $user_guid, $metadata);

-	}

-

-	/**

-	 * Can a user write to this entity's container.

-	 *

-	 * @param int $user_guid The user.

-	 * @return bool

-	 */

-	public function canWriteToContainer($user_guid = 0) {

-		return can_write_to_container($user_guid, $this->getGUID());

-	}

-

-	/**

-	 * Returns the access_id.

-	 *

-	 * @return int The access ID

-	 */

-	public function getAccessID() {

-		return $this->get('access_id');

-	}

-

-	/**

-	 * Returns the guid.

-	 *

-	 * @return int GUID

-	 */

-	public function getGUID() {

-		return $this->get('guid');

-	}

-

-	/**

-	 * Return the guid of the entity's owner.

-	 *

-	 * @return int The owner GUID

-	 */

-	public function getOwner() {

-		return $this->get('owner_guid');

-	}

-

-	/**

-	 * Returns the ElggEntity or child object of the owner of the entity.

-	 *

-	 * @return ElggEntity The owning user

-	 */

-	public function getOwnerEntity() {

-		return get_entity($this->get('owner_guid'));

-	}

-

-	/**

-	 * Returns the entity type

-	 *

-	 * @return string Entity type

-	 */

-	public function getType() {

-		return $this->get('type');

-	}

-

-	/**

-	 * Returns the entity subtype string

-	 *

-	 * @note This returns a string.  If you want the id, use ElggEntity::subtype.

-	 *

-	 * @return string The entity subtype

-	 */

-	public function getSubtype() {

-		// If this object hasn't been saved, then return the subtype string.

-		if (!((int) $this->guid > 0)) {

-			return $this->get('subtype');

-		}

-

-		return get_subtype_from_id($this->get('subtype'));

-	}

-

-	/**

-	 * Returns the UNIX epoch time that this entity was created

-	 *

-	 * @return int UNIX epoch time

-	 */

-	public function getTimeCreated() {

-		return $this->get('time_created');

-	}

-

-	/**

-	 * Returns the UNIX epoch time that this entity was last updated

-	 *

-	 * @return int UNIX epoch time

-	 */

-	public function getTimeUpdated() {

-		return $this->get('time_updated');

-	}

-

-	/**

-	 * Returns the URL for this entity

-	 *

-	 * @return string The URL

-	 * @see register_entity_url_handler()

-	 * @see ElggEntity::setURL()

-	 */

-	public function getURL() {

-		if (!empty($this->url_override)) {

-			return $this->url_override;

-		}

-		return get_entity_url($this->getGUID());

-	}

-

-	/**

-	 * Overrides the URL returned by getURL()

-	 *

-	 * @warning This override exists only for the life of the object.

-	 *

-	 * @param string $url The new item URL

-	 * @return string The URL

-	 */

-	public function setURL($url) {

-		$this->url_override = $url;

-		return $url;

-	}

-

-	/**

-	 * Returns a URL for the entity's icon.

-	 *

-	 * @param string $size Either 'large', 'medium', 'small' or 'tiny'

-	 * @return string The url or false if no url could be worked out.

-	 * @see get_entity_icon_url()

-	 */

-	public function getIcon($size = 'medium') {

-		if (isset($this->icon_override[$size])) {

-			return $this->icon_override[$size];

-		}

-		return get_entity_icon_url($this, $size);

-	}

-

-	/**

-	 * Set an icon override for an icon and size.

-	 *

-	 * @warning This override exists only for the life of the object.

-	 *

-	 * @param string $url The url of the icon.

-	 * @param string $size The size its for.

-	 * @return bool

-	 */

-	public function setIcon($url, $size = 'medium') {

-		$url = sanitise_string($url);

-		$size = sanitise_string($size);

-

-		if (!$this->icon_override) {

-			$this->icon_override = array();

-		}

-		$this->icon_override[$size] = $url;

-

-		return true;

-	}

-

-	/**

-	 * Tests to see whether the object has been fully loaded.

-	 *

-	 * @return bool

-	 */

-	public function isFullyLoaded() {

-		return ! ($this->attributes['tables_loaded'] < $this->attributes['tables_split']);

-	}

-

-	/**

-	 * Save attributes to the entities table.

-	 *

-	 * @return bool

-	 * @throws IOException

-	 */

-	public function save() {

-		$guid = (int) $this->guid;

-		if ($guid > 0) {

-			cache_entity($this);

-

-			return update_entity(

-				$this->get('guid'),

-				$this->get('owner_guid'),

-				$this->get('access_id'),

-				$this->get('container_guid')

-			);

-		} else {

-			// Create a new entity (nb: using attribute array directly 'cos set function does something special!)

-			$this->attributes['guid'] = create_entity($this->attributes['type'], $this->attributes['subtype'], $this->attributes['owner_guid'], $this->attributes['access_id'], $this->attributes['site_guid'], $this->attributes['container_guid']);

-			if (!$this->attributes['guid']) {

-				throw new IOException(elgg_echo('IOException:BaseEntitySaveFailed'));

-			}

-

-			// Save any unsaved metadata

-			// @todo How to capture extra information (access id etc)

-			if (sizeof($this->temp_metadata) > 0) {

-				foreach($this->temp_metadata as $name => $value) {

-					$this->$name = $value;

-					unset($this->temp_metadata[$name]);

-				}

-			}

-

-			// Save any unsaved annotations metadata.

-			// @todo How to capture extra information (access id etc)

-			if (sizeof($this->temp_annotations) > 0) {

-				foreach($this->temp_annotations as $name => $value) {

-					$this->annotate($name, $value);

-					unset($this->temp_annotations[$name]);

-				}

-			}

-

-			// set the subtype to id now rather than a string

-			$this->attributes['subtype'] = get_subtype_id($this->attributes['type'], $this->attributes['subtype']);

-

-			// Cache object handle

-			if ($this->attributes['guid']) {

-				cache_entity($this);

-			}

-

-			return $this->attributes['guid'];

-		}

-	}

-

-	/**

-	 * Loads attributes from the entities table into the object.

-	 *

-	 * @param int $guid

-	 * @return bool

-	 */

-	protected function load($guid) {

-		$row = get_entity_as_row($guid);

-

-		if ($row) {

-			// Create the array if necessary - all subclasses should test before creating

-			if (!is_array($this->attributes)) {

-				$this->attributes = array();

-			}

-

-			// Now put these into the attributes array as core values

-			$objarray = (array) $row;

-			foreach($objarray as $key => $value) {

-				$this->attributes[$key] = $value;

-			}

-

-			// Increment the portion counter

-			if (!$this->isFullyLoaded()) {

-				$this->attributes['tables_loaded']++;

-			}

-

-			// Cache object handle

-			if ($this->attributes['guid']) {

-				cache_entity($this);

-			}

-

-			return true;

-		}

-

-		return false;

-	}

-

-	/**

-	 * Disable this entity.

-	 *

-	 * Disabled entities are not returned by getter functions.

-	 * To enable an entity, use {@link enable_entity()}.

-	 *

-	 * Recursively disabling an entity will disable all entities

-	 * owned or contained by the parent entity.

-	 *

-	 * @internal Disabling an entity sets the 'enabled' column to 'no'.

-	 *

-	 * @param string $reason Optional reason

-	 * @param bool $recursive Recursively disable all contained entities?

-	 * @return bool

-	 * @see enable_entity()

-	 * @see ElggEntity::enable()

-	 */

-	public function disable($reason = "", $recursive = true) {

-		return disable_entity($this->get('guid'), $reason, $recursive);

-	}

-

-	/**

-	 * Enable an entity

-	 *

-	 * @warning Disabled entities can't be loaded unless

-	 * {@link access_show_hidden_entities(true)} has been called.

-	 *

-	 * @see enable_entity()

-	 * @see access_show_hiden_entities()

-	 * @return bool

-	 */

-	public function enable() {

-		return enable_entity($this->get('guid'));

-	}

-

-	/**

-	 * Is this entity enabled?

-	 *

-	 * @return boolean

-	 */

-	public function isEnabled() {

-		if ($this->enabled == 'yes') {

-			return true;

-		}

-

-		return false;

-	}

-

-	/**

-	 * Delete this entity.

-	 *

-	 * @return bool

-	 */

-	public function delete() {

-		return delete_entity($this->get('guid'));

-	}

-

-	/*

-	 * LOCATABLE INTERFACE

-	 */

-

-	/**

-	 * Sets the 'location' metadata for the entity

-	 *

-	 * @todo Unimplemented

-	 * @param string $location

-	 * @return true

-	 */

-	public function setLocation($location) {

-		$location = sanitise_string($location);

-

-		$this->location = $location;

-

-		return true;

-	}

-

-	/**

-	 * Set latitude and longitude metadata tags for a given entity.

-	 *

-	 * @param float $lat

-	 * @param float $long

-	 * @return true

-	 * @todo Unimplemented

-	 */

-	public function setLatLong($lat, $long) {

-		$lat = sanitise_string($lat);

-		$long = sanitise_string($long);

-

-		$this->set('geo:lat', $lat);

-		$this->set('geo:long', $long);

-

-		return true;

-	}

-

-	/**

-	 * Return the entity's latitude.

-	 *

-	 * @return int

-	 * @todo Unimplemented

-	 */

-	public function getLatitude() {

-		return $this->get('geo:lat');

-	}

-

-	/**

-	 * Return the entity's longitude

-	 *

-	 * @return Int

-	 */

-	public function getLongitude() {

-		return $this->get('geo:long');

-	}

-

-	/**

-	 * Return the entity's location

-	 *

-	 * @return string

-	 */

-	public function getLocation() {

-		return $this->get('location');

-	}

-

-	/*

-	 * NOTABLE INTERFACE

-	 */

-

-	/**

-	 * Set the time and duration of an object

-	 *

-	 * @param int $hour If ommitted, now is assumed.

-	 * @param int $minute If ommitted, now is assumed.

-	 * @param int $second If ommitted, now is assumed.

-	 * @param int $day If ommitted, now is assumed.

-	 * @param int $month If ommitted, now is assumed.

-	 * @param int $year If ommitted, now is assumed.

-	 * @param int $duration Duration of event, remainder of the day is assumed.

-	 * @return true

-	 * @todo Unimplemented

-	 */

-	public function setCalendarTimeAndDuration($hour = NULL, $minute = NULL, $second = NULL, $day = NULL, $month = NULL, $year = NULL, $duration = NULL) {

-		$start = mktime($hour, $minute, $second, $month, $day, $year);

-		$end = $start + abs($duration);

-		if (!$duration) {

-			$end = get_day_end($day,$month,$year);

-		}

-

-		$this->calendar_start = $start;

-		$this->calendar_end = $end;

-

-		return true;

-	}

-

-	/**

-	 * Returns the start timestamp.

-	 *

-	 * @return int

-	 * @todo Unimplemented

-	 */

-	public function getCalendarStartTime() {

-		return (int)$this->calendar_start;

-	}

-

-	/**

-	 * Returns the end timestamp.

-	 *

-	 * @todo Unimplemented

-	 */

-	public function getCalendarEndTime() {

-		return (int)$this->calendar_end;

-	}

-

-	/*

-	 * EXPORTABLE INTERFACE

-	 */

-

-	/**

-	 * Returns an array of fields which can be exported.

-	 *

-	 * @return array

-	 */

-	public function getExportableValues() {

-		return array(

-			'guid',

-			'type',

-			'subtype',

-			'time_created',

-			'time_updated',

-			'container_guid',

-			'owner_guid',

-			'site_guid'

-		);

-	}

-

-	/**

-	 * Export this class into an array of ODD Elements containing all necessary fields.

-	 * Override if you wish to return more information than can be found in $this->attributes (shouldn't happen)

-	 *

-	 * @return array

-	 */

-	public function export() {

-		$tmp = array();

-

-		// Generate uuid

-		$uuid = guid_to_uuid($this->getGUID());

-

-		// Create entity

-		$odd = new ODDEntity(

-			$uuid,

-			$this->attributes['type'],

-			get_subtype_from_id($this->attributes['subtype'])

-		);

-

-		$tmp[] = $odd;

-

-		$exportable_values = $this->getExportableValues();

-

-		// Now add its attributes

-		foreach ($this->attributes as $k => $v) {

-			$meta = NULL;

-

-			if (in_array( $k, $exportable_values)) {

-				switch ($k) {

-					case 'guid' : 			// Dont use guid in OpenDD

-					case 'type' :			// Type and subtype already taken care of

-					case 'subtype' :

-					break;

-

-					case 'time_created' :	// Created = published

-						$odd->setAttribute('published', date("r", $v));

-					break;

-

-					case 'site_guid' : // Container

-						$k = 'site_uuid';

-						$v = guid_to_uuid($v);

-						$meta = new ODDMetaData($uuid . "attr/$k/", $uuid, $k, $v);

-					break;

-

-					case 'container_guid' : // Container

-						$k = 'container_uuid';

-						$v = guid_to_uuid($v);

-						$meta = new ODDMetaData($uuid . "attr/$k/", $uuid, $k, $v);

-					break;

-

-					case 'owner_guid' :			// Convert owner guid to uuid, this will be stored in metadata

-						$k = 'owner_uuid';

-						$v = guid_to_uuid($v);

-						$meta = new ODDMetaData($uuid . "attr/$k/", $uuid, $k, $v);

-					break;

-

-					default :

-						$meta = new ODDMetaData($uuid . "attr/$k/", $uuid, $k, $v);

-				}

-

-				// set the time of any metadata created

-				if ($meta) {

-					$meta->setAttribute('published', date("r",$this->time_created));

-					$tmp[] = $meta;

-				}

-			}

-		}

-

-		// Now we do something a bit special.

-		/*

-		 * This provides a rendered view of the entity to foreign sites.

-		 */

-

-		elgg_set_viewtype('default');

-		$view = elgg_view_entity($this, true);

-		elgg_set_viewtype();

-

-		$tmp[] = new ODDMetaData($uuid . "volatile/renderedentity/", $uuid, 'renderedentity', $view , 'volatile');

-

-		return $tmp;

-	}

-

-	/*

-	 * IMPORTABLE INTERFACE

-	 */

-

-	/**

-	 * Import data from an parsed ODD xml data array.

-	 *

-	 * @param array $data

-	 * @param int $version

-	 * @return true

-	 */

-	public function import(ODD $data) {

-		if (!($data instanceof ODDEntity)) {

-			throw new InvalidParameterException(elgg_echo('InvalidParameterException:UnexpectedODDClass'));

-		}

-

-		// Set type and subtype

-		$this->attributes['type'] = $data->getAttribute('class');

-		$this->attributes['subtype'] = $data->getAttribute('subclass');

-

-		// Set owner

-		$this->attributes['owner_guid'] = get_loggedin_userid(); // Import as belonging to importer.

-

-		// Set time

-		$this->attributes['time_created'] = strtotime($data->getAttribute('published'));

-		$this->attributes['time_updated'] = time();

-

-		return true;

-	}

-

-	/*

-	 * SYSTEM LOG INTERFACE

-	 */

-

-	/**

-	 * Return an identification for the object for storage in the system log.

-	 * This id must be an integer.

-	 *

-	 * @return int

-	 */

-	public function getSystemLogID() {

-		return $this->getGUID();

-	}

-

-	/**

-	 * Return the class name of the object.

-	 */

-	public function getClassName() {

-		return get_class($this);

-	}

-

-	/**

-	 * For a given ID, return the object associated with it.

-	 * This is used by the river functionality primarily.

-	 *

-	 * This is useful for checking access permissions etc on objects.

-	 * @return guid

-	 */

-	public function getObjectFromID($id) {

-		return get_entity($id);

-	}

-

-	/**

-	 * Returns the GUID of the owner of this entity.

-	 *

-	 * @return int Owner guid

-	 */

-	public function getObjectOwnerGUID() {

-		return $this->owner_guid;

-	}

-

-	/**

-	 * Returns tags for this entity.

-	 *

-	 * @warning Tags must be registered by {@link elgg_register_tag_metadata_name()}.

-	 *

-	 * @param array $tag_names Optionally restrict by tag metadata names.

-	 * @return array

-	 */

-	public function getTags($tag_names = NULL) {

-		global $CONFIG;

-

-		if ($tag_names && !is_array($tag_names)) {

-			$tag_names = array($tag_names);

-		}

-

-		$valid_tags = elgg_get_registered_tag_metadata_names();

-		$entity_tags = array();

-

-		foreach ($valid_tags as $tag_name) {

-			if (is_array($tag_names) && !in_array($tag_name, $tag_names)) {

-				continue;

-			}

-

-			if ($tags = $this->$tag_name) {

-				// if a single tag, metadata returns a string.

-				// if multiple tags, metadata returns an array.

-				if (is_array($tags)) {

-					$entity_tags = array_merge($entity_tags, $tags);

-				} else {

-					$entity_tags[] = $tags;

-				}

-			}

-		}

-

-		return $entity_tags;

-	}

-

-	/*

-	 * ITERATOR INTERFACE

-	 */

-

-	/*

-	 * This lets an entity's attributes be displayed using foreach as a normal array.

-	 * Example: http://www.sitepoint.com/print/php5-standard-library

-	 */

-	private $valid = FALSE;

-

-	function rewind() {

-		$this->valid = (FALSE !== reset($this->attributes));

-	}

-

-	function current() {

-		return current($this->attributes);

-	}

-

-	function key() {

-		return key($this->attributes);

-	}

-

-	function next() {

-		$this->valid = (FALSE !== next($this->attributes));

-	}

-

-	function valid() {

-		return $this->valid;

-	}

-

-	/*

-	 * ARRAY ACCESS INTERFACE

-	 */

-

-	/*

-	 * This lets an entity's attributes be accessed like an associative array.

-	 * Example: http://www.sitepoint.com/print/php5-standard-library

-	 */

-	function offsetSet($key, $value) {

-		if ( array_key_exists($key, $this->attributes) ) {

-			$this->attributes[$key] = $value;

-		}

-	}

-

-	function offsetGet($key) {

-		if ( array_key_exists($key, $this->attributes) ) {

-			return $this->attributes[$key];

-		}

-	}

-

-	function offsetUnset($key) {

-		if ( array_key_exists($key, $this->attributes) ) {

-			$this->attributes[$key] = ""; // Full unsetting is dangerious for our objects

-		}

-	}

-

-	function offsetExists($offset) {

-		return array_key_exists($offset, $this->attributes);

-	}

+<?php
+/**
+ * The parent class for all Elgg Entities.
+ *
+ * An ElggEntity is one of the basic data models in Elgg.  It is the primary
+ * means of storing and retrieving data from the database.  An ElggEntity
+ * represents one row of the entities table.
+ *
+ * The ElggEntity class handles CRUD operations for the entities table.
+ * ElggEntity should always be extended by another class to handle CRUD
+ * operations on the type-specific table.
+ *
+ * ElggEntity uses magic methods for get and set, so any property that isn't
+ * declared will be assumed to be metadata and written to the database
+ * as metadata on the object.  All children classes must declare which
+ * properties are columns of the type table or they will be assumed
+ * to be metadata.  See ElggObject::initialise_entities() for examples.
+ *
+ * Core supports 4 types of entities: ElggObject, ElggUser, ElggGroup, and
+ * ElggSite.
+ *
+ * @tip Most plugin authors will want to extend the ElggObject class
+ * instead of this class.
+ *
+ * @package Elgg.Core
+ * @subpackage DataMode.Entities
+ * @link http://docs.elgg.org/DataModel/ElggEntity
+ */
+abstract class ElggEntity implements
+	Notable,    // Calendar interface
+	Locatable,  // Geocoding interface
+	Exportable, // Allow export of data
+	Importable, // Allow import of data
+	Loggable,	// Can events related to this object class be logged
+	Iterator,	// Override foreach behaviour
+	ArrayAccess // Override for array access
+{
+	/**
+	 * The main attributes of an entity.
+	 * Blank entries for all database fields should be created by the constructor.
+	 * Subclasses should add to this in their constructors.
+	 * Any field not appearing in this will be viewed as a
+	 */
+	protected $attributes;
+
+	/**
+	 * If set, overrides the value of getURL()
+	 */
+	protected $url_override;
+
+	/**
+	 * Icon override, overrides the value of getIcon().
+	 */
+	protected $icon_override;
+
+	/**
+	 * Holds metadata until entity is saved.  Once the entity is saved, metadata are written immediately to the database.
+	 */
+	protected $temp_metadata;
+
+	/**
+	 * Holds annotations until entity is saved.  Once the entity is saved, annotations are written immediately to the database.
+	 */
+	protected $temp_annotations;
+
+
+	/**
+	 * Volatile data structure for this object, allows for storage of data
+	 * in-memory that isn't sync'd back to the metadata table.
+	 */
+	protected $volatile;
+
+	/**
+	 * Initialise the attributes array.
+	 *
+	 * This is vital to distinguish between metadata and base parameters.
+	 *
+	 * @return void
+	 */
+	protected function initialise_attributes() {
+		initialise_entity_cache();
+
+		// Create attributes array if not already created
+		if (!is_array($this->attributes)) {
+			$this->attributes = array();
+		}
+		if (!is_array($this->temp_metadata)) {
+			$this->temp_metadata = array();
+		}
+		if (!is_array($this->temp_annotations)) {
+			$this->temp_annotations = array();
+		}
+		if (!is_array($this->volatile)) {
+			$this->volatile = array();
+		}
+
+		$this->attributes['guid'] = "";
+		$this->attributes['type'] = "";
+		$this->attributes['subtype'] = "";
+
+		$this->attributes['owner_guid'] = get_loggedin_userid();
+		$this->attributes['container_guid'] = get_loggedin_userid();
+
+		$this->attributes['site_guid'] = 0;
+		$this->attributes['access_id'] = ACCESS_PRIVATE;
+		$this->attributes['time_created'] = "";
+		$this->attributes['time_updated'] = "";
+		$this->attributes['last_action'] = '';
+		$this->attributes['enabled'] = "yes";
+
+		// There now follows a bit of a hack
+		/* Problem: To speed things up, some objects are split over several tables, this means that it requires
+		 * n number of database reads to fully populate an entity. This causes problems for caching and create events
+		 * since it is not possible to tell whether a subclassed entity is complete.
+		 * Solution: We have two counters, one 'tables_split' which tells whatever is interested how many tables
+		 * are going to need to be searched in order to fully populate this object, and 'tables_loaded' which is how
+		 * many have been loaded thus far.
+		 * If the two are the same then this object is complete.
+		 *
+		 * Use: isFullyLoaded() to check
+		 */
+		$this->attributes['tables_split'] = 1;
+		$this->attributes['tables_loaded'] = 0;
+	}
+
+	/**
+	 * Clone an entity
+	 *
+	 * Resets the guid so that the entity can be saved as a distinct entity from
+	 * the original. Creation time will be set when this new entity is saved.
+	 * The owner and container guids come from the original entity. The clone
+	 * method copies metadata but does not copy annotations or private settings.
+	 *
+	 * @note metadata will have its owner and access id set when the entity is saved
+	 * and it will be the same as that of the entity.
+	 */
+	public function __clone() {
+		$orig_entity = get_entity($this->guid);
+		if (!$orig_entity) {
+			elgg_log("Failed to clone entity with GUID $this->guid", "ERROR");
+			return;
+		}
+
+		$metadata_array = get_metadata_for_entity($this->guid);
+
+		$this->attributes['guid'] = "";
+
+		$this->attributes['subtype'] = $orig_entity->getSubtype();
+
+		// copy metadata over to new entity - slightly convoluted due to
+		// handling of metadata arrays
+		if (is_array($metadata_array)) {
+			// create list of metadata names
+			$metadata_names = array();
+			foreach ($metadata_array as $metadata) {
+				$metadata_names[] = $metadata['name'];
+			}
+			// arrays are stored with multiple enties per name
+			$metadata_names = array_unique($metadata_names);
+
+			// move the metadata over
+			foreach ($metadata_names as $name) {
+				$this->set($name, $orig_entity->$name);
+			}
+		}
+	}
+
+	/**
+	 * Return the value of a property.
+	 *
+	 * If $name is defined in $this->attributes that value is returned, otherwise it will
+	 * pull from the entity's metadata.
+	 *
+	 * Q: Why are we not using __get overload here?
+	 * A: Because overload operators cause problems during subclassing, so we put the code here and
+	 * create overloads in subclasses.
+	 * @todo What problems are these?
+	 *
+	 * @warning Subtype is returned as an id rather than the subtype string. Use getSubtype()
+	 * to get the subtype string.
+	 *
+	 * @param string $name
+	 * @return mixed Returns the value of a given value, or null.
+	 */
+	public function get($name) {
+		// See if its in our base attributes
+		if (isset($this->attributes[$name])) {
+			return $this->attributes[$name];
+		}
+
+		// No, so see if its in the meta data for this entity
+		$meta = $this->getMetaData($name);
+
+		// getMetaData returns NULL if $name is not found
+		return $meta;
+	}
+
+	/**
+	 * Sets the value of a property.
+	 *
+	 * If $name is defined in $this->attributes that value is set, otherwise it will
+	 * set the appropriate item of metadata.
+	 *
+	 * @warning It is important that your class populates $this->attributes with keys for all base attributes, anything
+	 * not in their gets set as METADATA.
+	 *
+	 * Q: Why are we not using __set overload here?
+	 * A: Because overload operators cause problems during subclassing, so we put the code here and
+	 * create overloads in subclasses.
+	 * @todo What problems?
+	 *
+	 * @param string $name
+	 * @param mixed $value
+	 */
+	public function set($name, $value) {
+		if (array_key_exists($name, $this->attributes)) {
+			// Certain properties should not be manually changed!
+			switch ($name) {
+				case 'guid':
+				case 'time_created':
+				case 'time_updated':
+				case 'last_action':
+					return FALSE;
+					break;
+				default:
+					$this->attributes[$name] = $value;
+					break;
+			}
+		} else {
+			return $this->setMetaData($name, $value);
+		}
+
+		return TRUE;
+	}
+
+	/**
+	 * Return the value of a piece of metadata.
+	 *
+	 * @param string $name
+	 * @return mixed The value, or NULL if not found.
+	 */
+	public function getMetaData($name) {
+		if ((int) ($this->guid) > 0) {
+			$md = get_metadata_byname($this->getGUID(), $name);
+		} else {
+			if (isset($this->temp_metadata[$name])) {
+				return $this->temp_metadata[$name];
+			}
+		}
+
+		if ($md && !is_array($md)) {
+			return $md->value;
+		} else if ($md && is_array($md)) {
+			return metadata_array_to_values($md);
+		}
+
+		return null;
+	}
+
+	/**
+	 * Return an attribute or a piece of metadata.
+	 *
+	 * @param string $name
+	 * @return mixed
+	 */
+	function __get($name) {
+		return $this->get($name);
+	}
+
+	/**
+	 * Set an attribute or a piece of metadata.
+	 *
+	 * @param string $name
+	 * @param mixed $value
+	 * @return mixed
+	 */
+	function __set($name, $value) {
+		return $this->set($name, $value);
+	}
+
+	/**
+	 * Test if property is set either as an attribute or metadata.
+	 *
+	 * @tip Use isset($entity->property)
+	 *
+	 * @param string $name The name of the attribute or metadata.
+	 * @return bool
+	 */
+	function __isset($name) {
+		return $this->$name !== NULL;
+	}
+
+	/**
+	 * Unset a property from metadata or attribute.
+	 *
+	 * @warning If you use this to unset an attribute, you must save the object!
+	 *
+	 * @param string $name The name of the attribute or metadata.
+	 */
+	function __unset($name) {
+		if (array_key_exists($name, $this->attributes)) {
+			$this->attributes[$name] = "";
+		}
+		else {
+			$this->clearMetaData($name);
+		}
+	}
+
+	/**
+	 * Set a piece of metadata.
+	 *
+	 * @tip Plugin authors should use the magic methods.
+	 *
+	 * @access private
+	 * @param string $name Name of the metadata
+	 * @param mixed $value Value of the metadata
+	 * @param string $value_type Types supported: integer and string. Will auto-identify if not set
+	 * @param bool $multiple (does not support associative arrays)
+	 * @return bool
+	 */
+	public function setMetaData($name, $value, $value_type = "", $multiple = false) {
+		if (is_array($value)) {
+			unset($this->temp_metadata[$name]);
+			remove_metadata($this->getGUID(), $name);
+			foreach ($value as $v) {
+				if ((int) $this->guid > 0) {
+					$multiple = true;
+					if (!create_metadata($this->getGUID(), $name, $v, $value_type,
+					$this->getOwner(), $this->getAccessID(), $multiple)) {
+						return false;
+					}
+				} else {
+					if (($multiple) && (isset($this->temp_metadata[$name]))) {
+						if (!is_array($this->temp_metadata[$name])) {
+							$tmp = $this->temp_metadata[$name];
+							$this->temp_metadata[$name] = array();
+							$this->temp_metadata[$name][] = $tmp;
+						}
+
+						$this->temp_metadata[$name][] = $value;
+					}
+					else {
+						$this->temp_metadata[$name] = $value;
+					}
+				}
+			}
+
+			return true;
+		} else {
+			unset($this->temp_metadata[$name]);
+			if ((int) $this->guid > 0) {
+				$result = create_metadata($this->getGUID(), $name, $value, $value_type, $this->getOwner(), $this->getAccessID(), $multiple);
+				return (bool)$result;
+			} else {
+				if (($multiple) && (isset($this->temp_metadata[$name]))) {
+					if (!is_array($this->temp_metadata[$name])) {
+						$tmp = $this->temp_metadata[$name];
+						$this->temp_metadata[$name] = array();
+						$this->temp_metadata[$name][] = $tmp;
+					}
+
+					$this->temp_metadata[$name][] = $value;
+				}
+				else {
+					$this->temp_metadata[$name] = $value;
+				}
+
+				return true;
+			}
+		}
+	}
+
+	/**
+	 * Remove metadata
+	 *
+	 * @warning Calling this with no or empty arguments will clear all metadata on the entity.
+	 * @param string The name of the metadata to clear
+	 * @return mixed The n
+	 */
+	public function clearMetaData($name = "") {
+		if (empty($name)) {
+			return clear_metadata($this->getGUID());
+		} else {
+			return remove_metadata($this->getGUID(), $name);
+		}
+	}
+
+
+	/**
+	 * Get a piece of volatile (non-persisted) data on this entity.
+	 *
+	 * @param string $name The name of the volatile data
+	 * @return mixed The value or NULL if not found.
+	 */
+	public function getVolatileData($name) {
+		if (!is_array($this->volatile)) {
+			$this->volatile = array();
+		}
+
+		if (array_key_exists($name, $this->volatile)) {
+			return $this->volatile[$name];
+		} else {
+			return NULL;
+		}
+	}
+
+
+	/**
+	 * Set a piece of volatile (non-persisted) data on this entity
+	 *
+	 * @param string $name
+	 * @param mixed $value
+	 */
+	public function setVolatileData($name, $value) {
+		if (!is_array($this->volatile)) {
+			$this->volatile = array();
+		}
+
+		$this->volatile[$name] = $value;
+	}
+
+
+	/**
+	 * Remove all relationships to and from this entity.
+	 *
+	 * @return true
+	 * @todo This should actually return if it worked.
+	 * @see ElggEntity::addRelationship()
+	 * @see ElggEntity::removeRelationship()
+	 */
+	public function clearRelationships() {
+		remove_entity_relationships($this->getGUID());
+		remove_entity_relationships($this->getGUID(), "", true);
+		return true;
+	}
+
+	/**
+	 * Add a relationship between this an another entity.
+	 *
+	 * @tip Read the relationship like "$guid is a $relationship of this entity."
+	 *
+	 * @param int $guid Entity to link to.
+	 * @param string $relationship The type of relationship.
+	 * @return bool
+	 * @see ElggEntity::removeRelationship()
+	 * @see ElggEntity::clearRelationships()
+	 */
+	public function addRelationship($guid, $relationship) {
+		return add_entity_relationship($this->getGUID(), $relationship, $guid);
+	}
+
+	/**
+	 * Remove a relationship
+	 *
+	 * @param int $guid
+	 * @param str $relationship
+	 * @return bool
+	 * @see ElggEntity::addRelationship()
+	 * @see ElggEntity::clearRelationships()
+	 */
+	public function removeRelationship($guid, $relationship) {
+		return remove_entity_relationship($this->getGUID(), $relationship, $guid);
+	}
+
+	/**
+	 * Adds a private setting to this entity.
+	 *
+	 * Private settings are similar to metadata but will not
+	 * be searched and there are fewer helper functions for them.
+	 *
+	 * @param $name
+	 * @param $value
+	 * @return bool
+	 * @link http://docs.elgg.org/DataModel/Entities/PrivateSettings
+	 */
+	function setPrivateSetting($name, $value) {
+		return set_private_setting($this->getGUID(), $name, $value);
+	}
+
+	/**
+	 * Returns a private setting value
+	 *
+	 * @param $name
+	 * @return mixed
+	 */
+	function getPrivateSetting($name) {
+		return get_private_setting($this->getGUID(), $name);
+	}
+
+	/**
+	 * Removes private setting
+	 *
+	 * @param $name
+	 * @return bool
+	 */
+	function removePrivateSetting($name) {
+		return remove_private_setting($this->getGUID(), $name);
+	}
+
+	/**
+	 * Adds an annotation to an entity.
+	 *
+	 * @warning By default, annotations are private.
+	 *
+	 * @param string $name
+	 * @param mixed $value
+	 * @param int $access_id
+	 * @param int $owner_id
+	 * @param string $vartype
+	 * @link http://docs.elgg.org/DataModel/Annotations
+	 */
+	function annotate($name, $value, $access_id = ACCESS_PRIVATE, $owner_id = 0, $vartype = "") {
+		if ((int) $this->guid > 0) {
+			return create_annotation($this->getGUID(), $name, $value, $vartype, $owner_id, $access_id);
+		} else {
+			$this->temp_annotations[$name] = $value;
+		}
+		return true;
+	}
+
+	/**
+	 * Returns an array of annotations.
+	 *
+	 * @param string $name
+	 * @param int $limit
+	 * @param int $offset
+	 * @param string $order asc or desc
+	 * @return array
+	 */
+	function getAnnotations($name, $limit = 50, $offset = 0, $order="asc") {
+		if ((int) ($this->guid) > 0) {
+			return get_annotations($this->getGUID(), "", "", $name, "", 0, $limit, $offset, $order);
+		} else {
+			return $this->temp_annotations[$name];
+		}
+	}
+
+	/**
+	 * Remove an annotation or all annotations for this entity.
+	 *
+	 * @warning Calling this method with no or an empty argument will remove all annotations on the entity.
+	 *
+	 * @param string $name
+	 * @return bool
+	 */
+	function clearAnnotations($name = "") {
+		return clear_annotations($this->getGUID(), $name);
+	}
+
+	/**
+	 * Count annotations.
+	 *
+	 * @param string $name The type of annotation.
+	 * @return int
+	 */
+	function countAnnotations($name = "") {
+		return count_annotations($this->getGUID(), "", "", $name);
+	}
+
+	/**
+	 * Get the average of an integer type annotation.
+	 *
+	 * @param string $name
+	 * @return int
+	 */
+	function getAnnotationsAvg($name) {
+		return get_annotations_avg($this->getGUID(), "", "", $name);
+	}
+
+	/**
+	 * Get the sum of integer type annotations of a given name.
+	 *
+	 * @param string $name
+	 * @return int
+	 */
+	function getAnnotationsSum($name) {
+		return get_annotations_sum($this->getGUID(), "", "", $name);
+	}
+
+	/**
+	 * Get the minimum of integer type annotations of given name.
+	 *
+	 * @param string $name
+	 * @return int
+	 */
+	function getAnnotationsMin($name) {
+		return get_annotations_min($this->getGUID(), "", "", $name);
+	}
+
+	/**
+	 * Get the maximum of integer type annotations of a given name.
+	 *
+	 * @param string $name
+	 * @return int
+	 */
+	function getAnnotationsMax($name) {
+		return get_annotations_max($this->getGUID(), "", "", $name);
+	}
+
+	/**
+	 * Gets an array of entities with a relationship to this entity.
+	 *
+	 * @param string $relationship Relationship type (eg "friends")
+	 * @param true|false $inverse Is this an inverse relationship?
+	 * @param int $limit Number of elements to return
+	 * @param int $offset Indexing offset
+	 * @return array|false An array of entities or false on failure
+	 */
+	function getEntitiesFromRelationship($relationship, $inverse = false, $limit = 50, $offset = 0) {
+		return elgg_get_entities_from_relationship(array(
+			'relationship' => $relationship,
+			'relationship_guid' => $this->getGUID(),
+			'inverse_relationship' => $inverse,
+			'limit' => $limit,
+			'offset' => $offset
+		));
+	}
+
+	/**
+	 * Gets the number of of entities from a specific relationship type
+	 *
+	 * @param string $relationship Relationship type (eg "friends")
+	 * @param bool $inverse_relationship
+	 * @return int|false The number of entities or false on failure
+	 */
+	function countEntitiesFromRelationship($relationship, $inverse_relationship = FALSE) {
+		return elgg_get_entities_from_relationship(array(
+			'relationship' => $relationship,
+			'relationship_guid' => $this->getGUID(),
+			'inverse_relationship' => $inverse_relationship,
+			'count' => TRUE
+		));
+	}
+
+	/**
+	 * Can a user edit this entity.
+	 *
+	 * @param int $user_guid The user GUID, optionally (defaults to the currently logged in user)
+	 * @return true|false
+	 */
+	function canEdit($user_guid = 0) {
+		return can_edit_entity($this->getGUID(), $user_guid);
+	}
+
+	/**
+	 * Can a user edit metadata on this entity
+	 *
+	 * @param ElggMetadata $metadata The piece of metadata to specifically check
+	 * @param int $user_guid The user GUID, optionally (defaults to the currently logged in user)
+	 * @return true|false
+	 */
+	function canEditMetadata($metadata = null, $user_guid = 0) {
+		return can_edit_entity_metadata($this->getGUID(), $user_guid, $metadata);
+	}
+
+	/**
+	 * Can a user write to this entity's container.
+	 *
+	 * @param int $user_guid The user.
+	 * @return bool
+	 */
+	public function canWriteToContainer($user_guid = 0) {
+		return can_write_to_container($user_guid, $this->getGUID());
+	}
+
+	/**
+	 * Returns the access_id.
+	 *
+	 * @return int The access ID
+	 */
+	public function getAccessID() {
+		return $this->get('access_id');
+	}
+
+	/**
+	 * Returns the guid.
+	 *
+	 * @return int GUID
+	 */
+	public function getGUID() {
+		return $this->get('guid');
+	}
+
+	/**
+	 * Return the guid of the entity's owner.
+	 *
+	 * @return int The owner GUID
+	 */
+	public function getOwner() {
+		return $this->get('owner_guid');
+	}
+
+	/**
+	 * Returns the ElggEntity or child object of the owner of the entity.
+	 *
+	 * @return ElggEntity The owning user
+	 */
+	public function getOwnerEntity() {
+		return get_entity($this->get('owner_guid'));
+	}
+
+	/**
+	 * Returns the entity type
+	 *
+	 * @return string Entity type
+	 */
+	public function getType() {
+		return $this->get('type');
+	}
+
+	/**
+	 * Returns the entity subtype string
+	 *
+	 * @note This returns a string.  If you want the id, use ElggEntity::subtype.
+	 *
+	 * @return string The entity subtype
+	 */
+	public function getSubtype() {
+		// If this object hasn't been saved, then return the subtype string.
+		if (!((int) $this->guid > 0)) {
+			return $this->get('subtype');
+		}
+
+		return get_subtype_from_id($this->get('subtype'));
+	}
+
+	/**
+	 * Returns the UNIX epoch time that this entity was created
+	 *
+	 * @return int UNIX epoch time
+	 */
+	public function getTimeCreated() {
+		return $this->get('time_created');
+	}
+
+	/**
+	 * Returns the UNIX epoch time that this entity was last updated
+	 *
+	 * @return int UNIX epoch time
+	 */
+	public function getTimeUpdated() {
+		return $this->get('time_updated');
+	}
+
+	/**
+	 * Returns the URL for this entity
+	 *
+	 * @return string The URL
+	 * @see register_entity_url_handler()
+	 * @see ElggEntity::setURL()
+	 */
+	public function getURL() {
+		if (!empty($this->url_override)) {
+			return $this->url_override;
+		}
+		return get_entity_url($this->getGUID());
+	}
+
+	/**
+	 * Overrides the URL returned by getURL()
+	 *
+	 * @warning This override exists only for the life of the object.
+	 *
+	 * @param string $url The new item URL
+	 * @return string The URL
+	 */
+	public function setURL($url) {
+		$this->url_override = $url;
+		return $url;
+	}
+
+	/**
+	 * Returns a URL for the entity's icon.
+	 *
+	 * @param string $size Either 'large', 'medium', 'small' or 'tiny'
+	 * @return string The url or false if no url could be worked out.
+	 * @see get_entity_icon_url()
+	 */
+	public function getIcon($size = 'medium') {
+		if (isset($this->icon_override[$size])) {
+			return $this->icon_override[$size];
+		}
+		return get_entity_icon_url($this, $size);
+	}
+
+	/**
+	 * Set an icon override for an icon and size.
+	 *
+	 * @warning This override exists only for the life of the object.
+	 *
+	 * @param string $url The url of the icon.
+	 * @param string $size The size its for.
+	 * @return bool
+	 */
+	public function setIcon($url, $size = 'medium') {
+		$url = sanitise_string($url);
+		$size = sanitise_string($size);
+
+		if (!$this->icon_override) {
+			$this->icon_override = array();
+		}
+		$this->icon_override[$size] = $url;
+
+		return true;
+	}
+
+	/**
+	 * Tests to see whether the object has been fully loaded.
+	 *
+	 * @return bool
+	 */
+	public function isFullyLoaded() {
+		return ! ($this->attributes['tables_loaded'] < $this->attributes['tables_split']);
+	}
+
+	/**
+	 * Save attributes to the entities table.
+	 *
+	 * @return bool
+	 * @throws IOException
+	 */
+	public function save() {
+		$guid = (int) $this->guid;
+		if ($guid > 0) {
+			cache_entity($this);
+
+			return update_entity(
+				$this->get('guid'),
+				$this->get('owner_guid'),
+				$this->get('access_id'),
+				$this->get('container_guid')
+			);
+		} else {
+			// Create a new entity (nb: using attribute array directly 'cos set function does something special!)
+			$this->attributes['guid'] = create_entity($this->attributes['type'], $this->attributes['subtype'], $this->attributes['owner_guid'], $this->attributes['access_id'], $this->attributes['site_guid'], $this->attributes['container_guid']);
+			if (!$this->attributes['guid']) {
+				throw new IOException(elgg_echo('IOException:BaseEntitySaveFailed'));
+			}
+
+			// Save any unsaved metadata
+			// @todo How to capture extra information (access id etc)
+			if (sizeof($this->temp_metadata) > 0) {
+				foreach($this->temp_metadata as $name => $value) {
+					$this->$name = $value;
+					unset($this->temp_metadata[$name]);
+				}
+			}
+
+			// Save any unsaved annotations metadata.
+			// @todo How to capture extra information (access id etc)
+			if (sizeof($this->temp_annotations) > 0) {
+				foreach($this->temp_annotations as $name => $value) {
+					$this->annotate($name, $value);
+					unset($this->temp_annotations[$name]);
+				}
+			}
+
+			// set the subtype to id now rather than a string
+			$this->attributes['subtype'] = get_subtype_id($this->attributes['type'], $this->attributes['subtype']);
+
+			// Cache object handle
+			if ($this->attributes['guid']) {
+				cache_entity($this);
+			}
+
+			return $this->attributes['guid'];
+		}
+	}
+
+	/**
+	 * Loads attributes from the entities table into the object.
+	 *
+	 * @param int $guid
+	 * @return bool
+	 */
+	protected function load($guid) {
+		$row = get_entity_as_row($guid);
+
+		if ($row) {
+			// Create the array if necessary - all subclasses should test before creating
+			if (!is_array($this->attributes)) {
+				$this->attributes = array();
+			}
+
+			// Now put these into the attributes array as core values
+			$objarray = (array) $row;
+			foreach($objarray as $key => $value) {
+				$this->attributes[$key] = $value;
+			}
+
+			// Increment the portion counter
+			if (!$this->isFullyLoaded()) {
+				$this->attributes['tables_loaded']++;
+			}
+
+			// Cache object handle
+			if ($this->attributes['guid']) {
+				cache_entity($this);
+			}
+
+			return true;
+		}
+
+		return false;
+	}
+
+	/**
+	 * Disable this entity.
+	 *
+	 * Disabled entities are not returned by getter functions.
+	 * To enable an entity, use {@link enable_entity()}.
+	 *
+	 * Recursively disabling an entity will disable all entities
+	 * owned or contained by the parent entity.
+	 *
+	 * @internal Disabling an entity sets the 'enabled' column to 'no'.
+	 *
+	 * @param string $reason Optional reason
+	 * @param bool $recursive Recursively disable all contained entities?
+	 * @return bool
+	 * @see enable_entity()
+	 * @see ElggEntity::enable()
+	 */
+	public function disable($reason = "", $recursive = true) {
+		return disable_entity($this->get('guid'), $reason, $recursive);
+	}
+
+	/**
+	 * Enable an entity
+	 *
+	 * @warning Disabled entities can't be loaded unless
+	 * {@link access_show_hidden_entities(true)} has been called.
+	 *
+	 * @see enable_entity()
+	 * @see access_show_hiden_entities()
+	 * @return bool
+	 */
+	public function enable() {
+		return enable_entity($this->get('guid'));
+	}
+
+	/**
+	 * Is this entity enabled?
+	 *
+	 * @return boolean
+	 */
+	public function isEnabled() {
+		if ($this->enabled == 'yes') {
+			return true;
+		}
+
+		return false;
+	}
+
+	/**
+	 * Delete this entity.
+	 *
+	 * @return bool
+	 */
+	public function delete() {
+		return delete_entity($this->get('guid'));
+	}
+
+	/*
+	 * LOCATABLE INTERFACE
+	 */
+
+	/**
+	 * Sets the 'location' metadata for the entity
+	 *
+	 * @todo Unimplemented
+	 * @param string $location
+	 * @return true
+	 */
+	public function setLocation($location) {
+		$location = sanitise_string($location);
+
+		$this->location = $location;
+
+		return true;
+	}
+
+	/**
+	 * Set latitude and longitude metadata tags for a given entity.
+	 *
+	 * @param float $lat
+	 * @param float $long
+	 * @return true
+	 * @todo Unimplemented
+	 */
+	public function setLatLong($lat, $long) {
+		$lat = sanitise_string($lat);
+		$long = sanitise_string($long);
+
+		$this->set('geo:lat', $lat);
+		$this->set('geo:long', $long);
+
+		return true;
+	}
+
+	/**
+	 * Return the entity's latitude.
+	 *
+	 * @return int
+	 * @todo Unimplemented
+	 */
+	public function getLatitude() {
+		return $this->get('geo:lat');
+	}
+
+	/**
+	 * Return the entity's longitude
+	 *
+	 * @return Int
+	 */
+	public function getLongitude() {
+		return $this->get('geo:long');
+	}
+
+	/**
+	 * Return the entity's location
+	 *
+	 * @return string
+	 */
+	public function getLocation() {
+		return $this->get('location');
+	}
+
+	/*
+	 * NOTABLE INTERFACE
+	 */
+
+	/**
+	 * Set the time and duration of an object
+	 *
+	 * @param int $hour If ommitted, now is assumed.
+	 * @param int $minute If ommitted, now is assumed.
+	 * @param int $second If ommitted, now is assumed.
+	 * @param int $day If ommitted, now is assumed.
+	 * @param int $month If ommitted, now is assumed.
+	 * @param int $year If ommitted, now is assumed.
+	 * @param int $duration Duration of event, remainder of the day is assumed.
+	 * @return true
+	 * @todo Unimplemented
+	 */
+	public function setCalendarTimeAndDuration($hour = NULL, $minute = NULL, $second = NULL, $day = NULL, $month = NULL, $year = NULL, $duration = NULL) {
+		$start = mktime($hour, $minute, $second, $month, $day, $year);
+		$end = $start + abs($duration);
+		if (!$duration) {
+			$end = get_day_end($day,$month,$year);
+		}
+
+		$this->calendar_start = $start;
+		$this->calendar_end = $end;
+
+		return true;
+	}
+
+	/**
+	 * Returns the start timestamp.
+	 *
+	 * @return int
+	 * @todo Unimplemented
+	 */
+	public function getCalendarStartTime() {
+		return (int)$this->calendar_start;
+	}
+
+	/**
+	 * Returns the end timestamp.
+	 *
+	 * @todo Unimplemented
+	 */
+	public function getCalendarEndTime() {
+		return (int)$this->calendar_end;
+	}
+
+	/*
+	 * EXPORTABLE INTERFACE
+	 */
+
+	/**
+	 * Returns an array of fields which can be exported.
+	 *
+	 * @return array
+	 */
+	public function getExportableValues() {
+		return array(
+			'guid',
+			'type',
+			'subtype',
+			'time_created',
+			'time_updated',
+			'container_guid',
+			'owner_guid',
+			'site_guid'
+		);
+	}
+
+	/**
+	 * Export this class into an array of ODD Elements containing all necessary fields.
+	 * Override if you wish to return more information than can be found in $this->attributes (shouldn't happen)
+	 *
+	 * @return array
+	 */
+	public function export() {
+		$tmp = array();
+
+		// Generate uuid
+		$uuid = guid_to_uuid($this->getGUID());
+
+		// Create entity
+		$odd = new ODDEntity(
+			$uuid,
+			$this->attributes['type'],
+			get_subtype_from_id($this->attributes['subtype'])
+		);
+
+		$tmp[] = $odd;
+
+		$exportable_values = $this->getExportableValues();
+
+		// Now add its attributes
+		foreach ($this->attributes as $k => $v) {
+			$meta = NULL;
+
+			if (in_array( $k, $exportable_values)) {
+				switch ($k) {
+					case 'guid' : 			// Dont use guid in OpenDD
+					case 'type' :			// Type and subtype already taken care of
+					case 'subtype' :
+					break;
+
+					case 'time_created' :	// Created = published
+						$odd->setAttribute('published', date("r", $v));
+					break;
+
+					case 'site_guid' : // Container
+						$k = 'site_uuid';
+						$v = guid_to_uuid($v);
+						$meta = new ODDMetaData($uuid . "attr/$k/", $uuid, $k, $v);
+					break;
+
+					case 'container_guid' : // Container
+						$k = 'container_uuid';
+						$v = guid_to_uuid($v);
+						$meta = new ODDMetaData($uuid . "attr/$k/", $uuid, $k, $v);
+					break;
+
+					case 'owner_guid' :			// Convert owner guid to uuid, this will be stored in metadata
+						$k = 'owner_uuid';
+						$v = guid_to_uuid($v);
+						$meta = new ODDMetaData($uuid . "attr/$k/", $uuid, $k, $v);
+					break;
+
+					default :
+						$meta = new ODDMetaData($uuid . "attr/$k/", $uuid, $k, $v);
+				}
+
+				// set the time of any metadata created
+				if ($meta) {
+					$meta->setAttribute('published', date("r",$this->time_created));
+					$tmp[] = $meta;
+				}
+			}
+		}
+
+		// Now we do something a bit special.
+		/*
+		 * This provides a rendered view of the entity to foreign sites.
+		 */
+
+		elgg_set_viewtype('default');
+		$view = elgg_view_entity($this, true);
+		elgg_set_viewtype();
+
+		$tmp[] = new ODDMetaData($uuid . "volatile/renderedentity/", $uuid, 'renderedentity', $view , 'volatile');
+
+		return $tmp;
+	}
+
+	/*
+	 * IMPORTABLE INTERFACE
+	 */
+
+	/**
+	 * Import data from an parsed ODD xml data array.
+	 *
+	 * @param array $data
+	 * @param int $version
+	 * @return true
+	 */
+	public function import(ODD $data) {
+		if (!($data instanceof ODDEntity)) {
+			throw new InvalidParameterException(elgg_echo('InvalidParameterException:UnexpectedODDClass'));
+		}
+
+		// Set type and subtype
+		$this->attributes['type'] = $data->getAttribute('class');
+		$this->attributes['subtype'] = $data->getAttribute('subclass');
+
+		// Set owner
+		$this->attributes['owner_guid'] = get_loggedin_userid(); // Import as belonging to importer.
+
+		// Set time
+		$this->attributes['time_created'] = strtotime($data->getAttribute('published'));
+		$this->attributes['time_updated'] = time();
+
+		return true;
+	}
+
+	/*
+	 * SYSTEM LOG INTERFACE
+	 */
+
+	/**
+	 * Return an identification for the object for storage in the system log.
+	 * This id must be an integer.
+	 *
+	 * @return int
+	 */
+	public function getSystemLogID() {
+		return $this->getGUID();
+	}
+
+	/**
+	 * Return the class name of the object.
+	 */
+	public function getClassName() {
+		return get_class($this);
+	}
+
+	/**
+	 * For a given ID, return the object associated with it.
+	 * This is used by the river functionality primarily.
+	 *
+	 * This is useful for checking access permissions etc on objects.
+	 * @return guid
+	 */
+	public function getObjectFromID($id) {
+		return get_entity($id);
+	}
+
+	/**
+	 * Returns the GUID of the owner of this entity.
+	 *
+	 * @return int Owner guid
+	 */
+	public function getObjectOwnerGUID() {
+		return $this->owner_guid;
+	}
+
+	/**
+	 * Returns tags for this entity.
+	 *
+	 * @warning Tags must be registered by {@link elgg_register_tag_metadata_name()}.
+	 *
+	 * @param array $tag_names Optionally restrict by tag metadata names.
+	 * @return array
+	 */
+	public function getTags($tag_names = NULL) {
+		global $CONFIG;
+
+		if ($tag_names && !is_array($tag_names)) {
+			$tag_names = array($tag_names);
+		}
+
+		$valid_tags = elgg_get_registered_tag_metadata_names();
+		$entity_tags = array();
+
+		foreach ($valid_tags as $tag_name) {
+			if (is_array($tag_names) && !in_array($tag_name, $tag_names)) {
+				continue;
+			}
+
+			if ($tags = $this->$tag_name) {
+				// if a single tag, metadata returns a string.
+				// if multiple tags, metadata returns an array.
+				if (is_array($tags)) {
+					$entity_tags = array_merge($entity_tags, $tags);
+				} else {
+					$entity_tags[] = $tags;
+				}
+			}
+		}
+
+		return $entity_tags;
+	}
+
+	/*
+	 * ITERATOR INTERFACE
+	 */
+
+	/*
+	 * This lets an entity's attributes be displayed using foreach as a normal array.
+	 * Example: http://www.sitepoint.com/print/php5-standard-library
+	 */
+	private $valid = FALSE;
+
+	function rewind() {
+		$this->valid = (FALSE !== reset($this->attributes));
+	}
+
+	function current() {
+		return current($this->attributes);
+	}
+
+	function key() {
+		return key($this->attributes);
+	}
+
+	function next() {
+		$this->valid = (FALSE !== next($this->attributes));
+	}
+
+	function valid() {
+		return $this->valid;
+	}
+
+	/*
+	 * ARRAY ACCESS INTERFACE
+	 */
+
+	/*
+	 * This lets an entity's attributes be accessed like an associative array.
+	 * Example: http://www.sitepoint.com/print/php5-standard-library
+	 */
+	function offsetSet($key, $value) {
+		if ( array_key_exists($key, $this->attributes) ) {
+			$this->attributes[$key] = $value;
+		}
+	}
+
+	function offsetGet($key) {
+		if ( array_key_exists($key, $this->attributes) ) {
+			return $this->attributes[$key];
+		}
+	}
+
+	function offsetUnset($key) {
+		if ( array_key_exists($key, $this->attributes) ) {
+			$this->attributes[$key] = ""; // Full unsetting is dangerious for our objects
+		}
+	}
+
+	function offsetExists($offset) {
+		return array_key_exists($offset, $this->attributes);
+	}
 }
\ No newline at end of file