Closes #1506: Added elgg_register_tag_metadata_name(), elgg_get_registered_tag_metadata_names(), and ElggEntity::getTags(). Search on tags updated to use registered tag names instead of hard-coded 'tags' metadata name.

git-svn-id: http://code.elgg.org/elgg/trunk@3936 36083f99-b078-4883-b0ff-0f9b5a30f544

4 files changed, 100 insertions, 12 deletions

diff --git a/CHANGES.txt b/CHANGES.txt
index af93f9913..4fcd086e3 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -43,7 +43,9 @@ http://code.elgg.org/elgg/.....
   * delete_relationship() triggers the hook delete:relationship and passes the relationship object. #1213
   * added ElggEntity::removeRelationship(). #1376.
   * get_entity_dates() supports order by. #1406.
-  * added elgg_http_add_url_query_elements().
+  * Added elgg_http_add_url_query_elements().
+  * Added elgg_register_tag_metadata_name() and elgg_get_registered_tag_metadata_names();
+  * Added ElggEntity::getTags().
 
  Services API:
   * Separated user and api authenticate processing
diff --git a/engine/lib/entities.php b/engine/lib/entities.php
index 930772943..eb98d5949 100644
--- a/engine/lib/entities.php
+++ b/engine/lib/entities.php
@@ -1121,6 +1121,32 @@ abstract class ElggEntity implements
 		return $this->owner_guid;
 	}
 
+	/**
+	 * Returns tags for this entity using registered tag metadata names.
+	 *
+	 * @return array
+	 */
+	public function getTags() {
+		global $CONFIG;
+
+		$valid_tags = elgg_get_registered_tag_metadata_names();
+		$entity_tags = array();
+
+		foreach ($valid_tags as $tag_name) {
+			if ($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 $entity_tags;
+	}
+
 	// ITERATOR INTERFACE //////////////////////////////////////////////////////////////
 	/*
 	 * This lets an entity's attributes be displayed using foreach as a normal array.
diff --git a/engine/lib/tags.php b/engine/lib/tags.php
index 6f0caf8af..ea8d3ebcc 100644
--- a/engine/lib/tags.php
+++ b/engine/lib/tags.php
@@ -15,7 +15,6 @@
  * This is quick and dirty.
  */
 function calculate_tag_size($min, $max, $number_of_tags, $buckets = 6) {
-
 	$delta =  (($max - $min) / $buckets);
 	$thresholds = array();
 
@@ -90,6 +89,11 @@ function get_tags($threshold = 1, $limit = 10, $metadata_name = "", $entity_type
 	$threshold = (int) $threshold;
 	$limit = (int) $limit;
 
+	$registered_tags = elgg_get_registered_tag_metadata_names();
+	if (!in_array($metadata_name, $registered_tags)) {
+		elgg_deprecated_notice('Tag metadata names must be registered by elgg_register_tag_metadata_name()', 1.7);
+	}
+
 	if (!empty($metadata_name)) {
 		$metadata_name = (int) get_metastring_id($metadata_name);
 		// test if any metadata with that name
@@ -116,8 +120,6 @@ function get_tags($threshold = 1, $limit = 10, $metadata_name = "", $entity_type
 		$site_guid = $CONFIG->site_id;
 	}
 
-	//$access = get_access_list();
-
 	$query = "SELECT msvalue.string as tag, count(msvalue.id) as total ";
 	$query .= "FROM {$CONFIG->dbprefix}entities e join {$CONFIG->dbprefix}metadata md on md.entity_guid = e.guid ";
 	if ($entity_subtype > 0) {
@@ -154,9 +156,8 @@ function get_tags($threshold = 1, $limit = 10, $metadata_name = "", $entity_type
 		$query .= " and e.time_created<=$end_ts";
 	}
 
-	//$userid = get_loggedin_userid();
-	//$query .= " and (e.access_id in {$access} or (e.access_id = " . ACCESS_PRIVATE . " and e.owner_guid = {$userid}))";
-	$query .= ' and ' . get_access_sql_suffix("e"); // Add access controls
+	// Add access controls
+	$query .= ' and ' . get_access_sql_suffix("e");
 
 	$query .= " group by msvalue.string having total > {$threshold} order by total desc limit {$limit} ";
 
@@ -179,7 +180,53 @@ function get_tags($threshold = 1, $limit = 10, $metadata_name = "", $entity_type
  */
 
 function display_tagcloud($threshold = 1, $limit = 10, $metadata_name = "", $entity_type = "object", $entity_subtype = "", $owner_guid = "", $site_guid = -1, $start_ts = "", $end_ts = "") {
+
+	if (!in_array($metadata_name, $registered_tags)) {
+		elgg_deprecated_notice('Tag metadata names must be registered by elgg_register_tag_metadata_name()', 1.7);
+	}
+
 	return elgg_view("output/tagcloud",array('value' => get_tags($threshold, $limit, $metadata_name, $entity_type, $entity_subtype, $owner_guid, $site_guid, $start_ts, $end_ts),
-											'object' => $entity_type, 
+											'object' => $entity_type,
 											'subtype' => $entity_subtype));
-}
\ No newline at end of file
+}
+
+/**
+ * Registers a metadata name as containing tags for an entity.
+ * This is required if you are using a non-standard metadata name
+ * for your tags.
+ *
+ * @since 1.7
+ *
+ * @param string $name
+ * @return TRUE
+ */
+function elgg_register_tag_metadata_name($name) {
+	global $CONFIG;
+
+	if (!isset($CONFIG->registered_tag_metadata_names)) {
+		$CONFIG->registered_tag_metadata_names = array();
+	}
+
+	if (!in_array($name, $CONFIG->registered_tag_metadata_names)) {
+		$CONFIG->registered_tag_metadata_names[] = $name;
+	}
+
+	return TRUE;
+}
+
+/**
+ * Returns an array of valid metadata names for tags.
+ *
+ * @since 1.7
+ *
+ * @return array
+ */
+function elgg_get_registered_tag_metadata_names() {
+	global $CONFIG;
+
+	$names = (isset($CONFIG->registered_tag_metadata_names)) ? $CONFIG->registered_tag_metadata_names : array();
+	return $names;
+}
+
+// register the standard tags metadata name
+elgg_register_tag_metadata_name('tags');
\ No newline at end of file
diff --git a/mod/search/search_hooks.php b/mod/search/search_hooks.php
index 77ab5c6e3..a74b1c2b3 100644
--- a/mod/search/search_hooks.php
+++ b/mod/search/search_hooks.php
@@ -165,9 +165,22 @@ function search_users_hook($hook, $type, $value, $params) {
 function search_tags_hook($hook, $type, $value, $params) {
 	global $CONFIG;
 
+	$valid_tags = elgg_get_registered_tag_metadata_names();
+
 	// @todo will need to split this up to support searching multiple tags at once.
 	$query = sanitise_string($params['query']);
-	$params['metadata_name_value_pair'] = array ('name' => 'tags', 'value' => $query, 'case_sensitive' => FALSE);
+
+	$name_value_pairs = array();
+	foreach ($valid_tags as $tag_name) {
+		$name_value_pairs[] = array (
+			'name' => $tag_name,
+			'value' => $query,
+			'case_sensitive' => FALSE
+		);
+	}
+
+	$params['metadata_name_value_pairs'] = $name_value_pairs;
+	$params['metadata_name_value_pairs_operator'] = 'OR';
 
 	$entities = elgg_get_entities_from_metadata($params);
 	$params['count'] = TRUE;
@@ -180,10 +193,10 @@ function search_tags_hook($hook, $type, $value, $params) {
 
 	// add the volatile data for why these entities have been returned.
 	foreach ($entities as $entity) {
-		$tags = $entity->tags;
+		$tags = $entity->getTags();
 
 		if (is_array($tags)) {
-			$tags = implode(', ', $entity->tags);
+			$tags = implode(', ', $tags);
 		}
 
 		// Nick told me my idea was dirty, so I'm hard coding the numbers.