--- /dev/null
+<?php // $Id$
+
+require_once('../config.php');
+
+/**
+ * Creates tags
+
+ * Ex: tag_create('A VeRY cOoL Tag, Another NICE tag')
+ * will create the following normalized {@link tag_normalize()} entries in tags table:
+ * 'a very cool tag'
+ * 'another nice tag'
+ *
+ * @param string $tag_names_csv CSV tag names (can be unnormalized) to be created.
+ * @param string $tag_type type of tag to be created ("default" is the default value).
+ * @return an array of tags ids, indexed by their normalized names
+ */
+function tag_create($tag_names_csv, $tag_type="default") {
+ global $USER;
+
+ $normalized_tag_names_csv = tag_normalize($tag_names_csv) ;
+
+ $tags = explode(",", $normalized_tag_names_csv );
+
+ $tag_object = new StdClass;
+ $tag_object->tagtype = $tag_type;
+ $tag_object->userid = $USER->id;
+
+ $systemcontext = get_context_instance(CONTEXT_SYSTEM);
+ $can_create_tags = has_capability('moodle/tag:create',$systemcontext);
+
+ foreach ($tags as $tag_name) {
+
+ $tag_object->name = $tag_name;
+ $tag_object->timemodified = time();
+
+// if ( !record_exists('tag', 'name', $tag_name) && !empty($tag_name) && !is_numeric($tag_name) ) {
+ if ( $can_create_tags && !empty($tag_name) && !is_numeric($tag_name) ) {
+ insert_record('tag', $tag_object);
+ }
+ }
+
+ return tags_id($normalized_tag_names_csv);
+
+}
+
+/**
+ * Deletes tags
+ *
+ * Ex 1: tag_delete('a very cool tag, another nice tag')
+ * Will delete the tags with names 'a very cool tag' and 'another nice tag' from the 'tags' table, if they exist!
+ *
+ * Ex 2: tag_delete('computers, 123, 143, algorithms')
+ * Will delete tags with names 'computers' and 'algorithms' and tags with ids 123 and 143.
+ *
+ *
+ * @param string $tag_names_or_ids_csv **normalized** tag names or ids of the tags to be deleted.
+ */
+
+function tag_delete($tag_names_or_ids_csv) {
+
+ //covert all ids to names
+ $tag_names_csv = tag_name_from_string($tag_names_or_ids_csv);
+
+ //put apostrophes in names
+ $tag_names_csv_with_apos = "'" . str_replace(',', "','", $tag_names_csv) . "'";
+
+ delete_records_select('tag',"name IN ($tag_names_csv_with_apos)");
+
+}
+
+/**
+ * Get all tags from the records
+ *
+ * @param string $tag_types_csv (optional, default value is "default". If '*' is passed, tags of any type will be returned).
+ * @param string $sort an order to sort the results in (optional, a valid SQL ORDER BY parameter).
+ * @param string $fields a comma separated list of fields to return
+ * (optional, by default 'id, tagtype, name'). The first field will be used as key for the
+ * array so must be a unique field such as 'id'.
+ */
+function get_all_tags($tag_types_csv="default", $sort='name ASC', $fields='id, tagtype, name') {
+
+ if ($tag_types_csv == '*'){
+ return get_records('tag', '', '', $sort, $fields);
+ }
+
+ $tag_types_csv_with_apos = "'" . str_replace(',', "','", $tag_types_csv ) . "'";
+
+ return get_records_list('tag', 'tagtype', $tag_types_csv_with_apos, $sort, $fields);
+}
+
+/**
+ * Determines if a tag exists
+ *
+ * @param string $tag_name_or_id **normalized** tag name, or an id.
+ * @return true if exists or false otherwise
+ *
+ */
+function tag_exists($tag_name_or_id) {
+
+ if (is_numeric($tag_name_or_id)) {
+ return record_exists('tag', 'id', $tag_name_or_id);
+ }
+ elseif (is_string($tag_name_or_id)) {
+ return record_exists('tag', 'name', $tag_name_or_id);
+ }
+}
+
+/**
+ * Function that returns the id of a tag
+ *
+ * @param String $tag_name **normalized** name of the tag
+ * @return int id of the matching tag
+ */
+function tag_id($tag_name) {
+ $tag = get_record('tag', 'name', trim($tag_name), '', '', '', '', 'id');
+ return $tag->id;
+}
+
+/**
+ * Function that returns the ids of tags
+ *
+ * Ex: tags_id('computers, algorithms')
+ *
+ * @param String $tag_names_csv comma separated **normalized** tag names.
+ * @return Array array with the tags ids, indexed by their **normalized** names
+ */
+function tags_id($tag_names_csv) {
+
+ $normalized_tag_names_csv = tag_normalize($tag_names_csv);
+ $tag_names_csv_with_apos = "'" . str_replace(',', "','", $normalized_tag_names_csv ) . "'";
+
+ $tag_objects = get_records_list('tag','name', $tag_names_csv_with_apos, "" , "name, id" );
+
+ $tags_ids = array();
+ foreach ($tag_objects as $tag) {
+ $tags_ids[$tag->name] = $tag->id;
+ }
+
+ return $tags_ids;
+}
+
+/**
+ * Function that returns the name of a tag
+ *
+ * @param int $tag_id id of the tag
+ * @return String name of the tag with the id passed
+ */
+function tag_name($tag_id) {
+ $tag = get_record('tag', 'id', $tag_id, '', '', '', '', 'name');
+ return $tag->name;
+}
+
+/**
+ * Function that retrieves the names of tags given their ids
+ *
+ * @param String $tag_ids_csv comma separated tag ids
+ * @return Array an array with the tags names, indexed by their ids
+ */
+
+function tags_name($tag_ids_csv) {
+
+ $tag_ids_csv_with_apos = "'" . str_replace(',', "','", $tag_ids_csv ) . "'";
+
+ $tag_objects = get_records_list('tag','id', $tag_ids_csv_with_apos, "" , "name, id" );
+
+ $tags_names = array();
+ foreach ($tag_objects as $tag) {
+ $tags_names[$tag->id] = $tag->name;
+ }
+
+ return $tags_names;
+}
+
+/**
+ * Function that retrieves a tag object by its id
+ *
+ * @param String $tag_id
+ * @return mixed a fieldset object containing the first matching record, or false if none found
+ */
+function tag_by_id($tag_id) {
+
+ return get_record('tag','id',$tag_id);
+}
+
+/**
+ * Function that retrieves a tag object by its name
+ *
+ * @param String $tag_name
+ * @return mixed a fieldset object containing the first matching record, or false if none found
+ */
+function tag_by_name($tag_name) {
+ $tag = get_record('tag','name',$tag_name);
+ return $tag;
+}
+
+/**
+ * Returns comma separated ids of tags given a string with comma separated names or ids of tags
+ *
+ * Ex: tag_id_from_string('moodle, 12, education, 33, 11')
+ * might return the string '10,12,22,33,11'
+ *
+ * This is a helper function used by functions of this API to process function arguments ($tag_name_or_id)
+ *
+ * @param string $tag_names_or_ids_csv comma separated **normalized** names or ids of tags
+ * @return int comma separated ids of the tags
+ */
+function tag_id_from_string($tag_names_or_ids_csv) {
+
+ $tag_names_or_ids = explode(',', $tag_names_or_ids_csv);
+
+ $tag_ids = array();
+ foreach ($tag_names_or_ids as $name_or_id) {
+
+ if (is_numeric($name_or_id)){
+ $tag_ids[] = $name_or_id;
+ }
+ elseif (is_string($name_or_id)) {
+ $tag_ids[] = tag_id( $name_or_id );
+ }
+
+ }
+
+ $tag_ids_csv = implode(',',$tag_ids);
+ $tag_ids_csv = str_replace(' ', '', $tag_ids_csv);
+
+ return rtrim($tag_ids_csv, ',');
+}
+
+/**
+ * Returns comma separated **normalized** names of tags given a string with comma separated names or ids of tags
+ *
+ * Ex: tag_name_from_string('mOOdle, 12, eduCAtIOn, 33, 11')
+ * might return the string 'moodle,computers,education,algorithms,software'
+ *
+ * This is a helper function used by functions of this API to process function arguments ($tag_name_or_id)
+ *
+ * @param string $tag_names_or_ids_csv comma separated **normalized** names or ids of tags
+ * @return int comma separated ids of the tags
+ */
+function tag_name_from_string($tag_names_or_ids_csv) {
+
+ $tag_names_or_ids = explode(',', $tag_names_or_ids_csv);
+
+ $tag_names = array();
+ foreach ($tag_names_or_ids as $name_or_id) {
+
+ if (is_numeric($name_or_id)){
+ $tag_names[] = tag_name($name_or_id);
+ }
+ elseif (is_string($name_or_id)) {
+ $tag_names[] = tag_normalize($name_or_id);
+ }
+
+ }
+
+ $tag_names_csv = implode(',',$tag_names);
+
+ return rtrim($tag_names_csv, ',');
+
+}
+
+/**
+ * Associates a tag with an item
+ *
+ * Ex 1: tag_an_item('user', '1', 'hisTOrY, RELIGIONS, roman' )
+ * This will tag an user whose id is 1 with "history", "religions", "roman"
+ * If the tag names passed do not exist, they will get created.
+ *
+ * Ex 2: tag_an_item('user', '1', 'hisTory, 12, 11, roman')
+ * This will tag an user whose id is 1 with 'history', 'roman' and with tags of ids 12 and 11
+ *
+ * @param string $item_type name of the table where the item is stored. Ex: 'user'
+ * @param string $item_id id of the item to be tagged
+ * @param string $tag_names_or_ids_csv comma separated tag names (can be unormalized) or ids of existing tags
+ * @param string $tag_type type of the tags that are beeing added (optional, default value is "default")
+ */
+
+function tag_an_item($item_type, $item_id, $tag_names_or_ids_csv, $tag_type="default") {
+
+ $norm_tag_names_or_ids_csv = tag_normalize($tag_names_or_ids_csv);
+
+ //convert any tag ids passed to their corresponding tag names
+ $tag_names_csv = tag_name_from_string($norm_tag_names_or_ids_csv);
+
+ //create the tags
+ $tags_created_ids = tag_create($tag_names_csv,$tag_type);
+
+ $tag_instance = new StdClass;
+ $tag_instance->itemtype = $item_type;
+ $tag_instance->itemid = $item_id;
+
+ //create tag instances
+ foreach ($tags_created_ids as $tag_id) {
+ $tag_instance->tagid = $tag_id;
+ insert_record('tag_instance',$tag_instance);
+ }
+
+
+ // update_tag_correlations($item_type, $item_id);
+
+}
+
+
+/**
+ * Updates the tags associated with an item
+ *
+ * Ex 1:
+ * Suppose user 1 is tagged only with "algorithms", "computers" and "software"
+ * By calling update_item_tags('user', 1, 'algorithms, software, mathematics')
+ * User 1 will now be tagged only with "algorithms", "software" and "mathematics"
+ *
+ * Ex 2:
+ * update_item_tags('user', '1', 'algorithms, 12, 13')
+ * User 1 will now be tagged only with "algorithms", and with tags of ids 12 and 13
+ *
+ *
+ * @param string $item_type name of the table where the item is stored. Ex: 'user'
+ * @param string $item_id id of the item to be tagged
+ * @param string $tag_names_or_ids_csv comma separated tag names (can be unormalized) or ids of existing tags
+ * @param string $tag_type type of the tags that are beeing added (optional, default value is "default")
+ */
+
+function update_item_tags($item_type, $item_id, $tag_names_or_ids_csv, $tag_type="default") {
+
+ //if $tag_names_csv is an empty string, remove all tag associations of the item
+ if( empty($tag_names_or_ids_csv) ){
+ untag_an_item($item_type, $item_id);
+ return;
+ }
+
+ //normalize tags names
+ $norm_tag_names_or_ids_csv = tag_normalize($tag_names_or_ids_csv);
+
+ //convert any tag ids passed to their corresponding tag names
+ $tag_names_csv = tag_name_from_string($norm_tag_names_or_ids_csv);
+
+ //associate the tags passed with the item
+ tag_an_item($item_type, $item_id, $tag_names_csv, $tag_type );
+
+ //get the ids of the tags passed
+ $existing_and_new_tags_ids = tags_id( $tag_names_csv );
+
+ // delete any tag instance with $item_type and $item_id
+ // that are not in $tag_names_csv
+ $tags_id_csv = "'" . implode("','", $existing_and_new_tags_ids) . "'" ;
+
+ $select = "
+ itemid = '{$item_id}'
+ AND
+ itemtype = '{$item_type}'
+ AND
+ tagid NOT IN ({$tags_id_csv})
+ ";
+
+ delete_records_select('tag_instance', $select);
+
+}
+
+/**
+ * Removes the association of an item with a tag
+ *
+ * Ex: untag_an_item('user', '1', 'history, 11, roman' )
+ * The user with id 1 will no longer be tagged with 'history', 'roman' and the tag of id 11
+ * Calling untag_an_item('user','1') will remove all tags associated with user 1.
+ *
+ * @param string $item_type name of the table where the item is stored. Ex: 'user'
+ * @param string $item_id id of the item to be untagged
+ * @param string $tag_names_or_ids_csv comma separated tag **normalized** names or ids of existing tags (optional,
+ * if none is given, all tags of the item will be removed)
+ */
+
+function untag_an_item($item_type, $item_id, $tag_names_or_ids_csv='') {
+
+ if ($tag_names_or_ids_csv == ""){
+
+ delete_records('tag_instance','itemtype', $item_type, 'itemid', $item_id);
+
+ }
+ else {
+
+ $tag_ids_csv = tag_id_from_string($norm_tag_names_or_ids_csv);
+
+ $tag_ids_csv_with_apos = "'" . str_replace(',', "','", $tag_ids_csv ) . "'";
+
+ delete_records_select('tag_instance',
+ "tagid IN ($tags_id_csv_with_apos) AND itemtype='$item_type' AND itemid='$item_id'");
+ }
+
+ //update_tag_correlations($item_type, $item_id);
+
+}
+
+/**
+ * Function that gets the tags that are associated with an item
+ *
+ * Ex: get_item_tags('user', '1')
+ *
+ * @param string $item_type name of the table where the item is stored. Ex: 'user'
+ * @param string $item_id id of the item beeing queried
+ * @param string $fields tag fields to be selected (optional, default is 'id, name, tagtype')
+ * @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
+ * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
+ * @return mixed an array of objects, or false if no records were found or an error occured.
+ */
+
+function get_item_tags($item_type, $item_id, $fields='id, name, tagtype, flag', $limitfrom='', $limitnum='') {
+
+ global $CFG;
+
+ $fields = 'tg.' . $fields;
+ $fields = str_replace(',', ',tg.', $fields);
+
+ $query = "
+ SELECT
+ {$fields}
+ FROM
+ {$CFG->prefix}tag_instance ti
+ INNER JOIN
+ {$CFG->prefix}tag tg
+ ON
+ tg.id = ti.tagid
+ WHERE
+ ti.itemtype = '{$item_type}' AND
+ ti.itemid = '{$item_id}'";
+
+ return get_records_sql($query, $limitfrom, $limitnum);
+
+}
+
+
+
+/**
+ * Function that returns the items of a certain type associated with a certain tag
+ *
+ * Ex 1: get_items_tagged_with('user', 'banana')
+ * Ex 2: get_items_tagged_with('user', '11')
+ *
+ * @param string $item_type name of the table where the item is stored. Ex: 'user'
+ * @param string $tag_name_or_id is a single **normalized** tag name or the id of a tag
+ * @param string $sort an order to sort the results in (optional, a valid SQL ORDER BY parameter).
+ * (to avoid field name ambiguity in the query, use the identifier "it" Ex: 'it.name ASC' )
+ * @param string $fields a comma separated list of fields to return
+ * (optional, by default all fields are returned). The first field will be used as key for the
+ * array so must be a unique field such as 'id'.
+ * @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
+ * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
+ * @return mixed an array of objects indexed by their ids, or false if no records were found or an error occured.
+ */
+
+function get_items_tagged_with($item_type, $tag_name_or_id, $sort='', $fields='*', $limitfrom='', $limitnum='') {
+
+ global $CFG;
+
+ $tag_id = tag_id_from_string($tag_name_or_id);
+
+ $fields = 'it.' . $fields;
+ $fields = str_replace(',', ',it.', $fields);
+
+ if ($sort) {
+ $sort = ' ORDER BY '. $sort;
+ }
+
+ $query = "
+ SELECT
+ {$fields}
+ FROM
+ {$CFG->prefix}{$item_type} it
+ INNER JOIN
+ {$CFG->prefix}tag_instance tt
+ ON
+ it.id = tt.itemid
+ WHERE
+ tt.itemtype = '{$item_type}' AND
+ tt.tagid = '{$tag_id}'
+ {$sort}
+ ";
+
+
+ return get_records_sql($query, $limitfrom, $limitnum);
+
+}
+
+/**
+ * Returns the number of items tagged with a tag
+ *
+ * @param string $tag_name_or_id is a single **normalized** tag name or the id of a tag
+ * @param string $item_type name of the table where the item is stored. Ex: 'user' (optional, if none is set any
+ * type will be counted)
+ * @return int the count. If an error occurrs, 0 is returned.
+ */
+function count_items_tagged_with($tag_name_or_id, $item_type='') {
+
+ global $CFG;
+
+ $tag_id = tag_id_from_string($tag_name_or_id);
+
+ if (empty($item_type)){
+ $query = "
+ SELECT
+ COUNT(*) AS count
+ FROM
+ {$CFG->prefix}tag_instance tt
+ WHERE
+ tagid = {$tag_id}";
+ }
+ else
+ {
+ $query = "
+ SELECT
+ COUNT(*) AS count
+ FROM
+ {$CFG->prefix}{$item_type} it
+ INNER JOIN
+ {$CFG->prefix}tag_instance tt
+ ON
+ it.id = tt.itemid
+ WHERE
+ tt.itemtype = '{$item_type}' AND
+ tt.tagid = '{$tag_id}' ";
+ }
+
+
+ return count_records_sql($query);
+
+}
+
+
+/**
+ * Determines if an item is tagged with a certain tag
+ *
+ * @param string $item_type name of the table where the item is stored. Ex: 'user'
+ * @param string $item_id id of the item beeing queried
+ * @param string $tag_name_or_id is a single **normalized** tag name or the id of a tag
+ * @return bool true if a matching record exists, else false.
+ */
+function is_item_tagged_with($item_type,$item_id, $tag_name_or_id) {
+
+ $tag_id = tag_id_from_string($tag_name_or_id);
+
+ return record_exists('tag_instance','itemtype',$item_type,'itemid',$item_id, 'tagid', $tag_id);
+}
+
+/**
+ * Search for tags with names that match some text
+ *
+ * @param string $text string that the tag names will be matched against
+ * @param boolean $ordered If true, tags are ordered by their popularity. If false, no ordering.
+ * @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
+ * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
+ * @return mixed an array of objects, or false if no records were found or an error occured.
+ */
+
+function search_tags($text, $ordered=true, $limitfrom='' , $limitnum='' ) {
+
+ global $CFG;
+
+ $text = tag_normalize($text);
+
+ if ($ordered) {
+ $query = "
+ SELECT
+ tg.id, tg.name, COUNT(ti.id) AS count
+ FROM
+ {$CFG->prefix}tag tg
+ LEFT JOIN
+ {$CFG->prefix}tag_instance ti
+ ON
+ tg.id = ti.tagid
+ WHERE
+ tg.name
+ LIKE
+ '%{$text}%'
+ GROUP BY
+ tg.id
+ ORDER BY
+ count
+ DESC";
+ } else {
+ $query = "
+ SELECT
+ tg.id, tg.name
+ FROM
+ {$CFG->prefix}tag tg
+ WHERE
+ tg.name
+ LIKE
+ '%{$text}%'
+ ";
+ }
+
+
+ return get_records_sql($query, $limitfrom , $limitnum);
+
+}
+
+/**
+ * Function that returns tags that start with some text
+ *
+ * @param string $text string that the tag names will be matched against
+ * @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
+ * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
+ * @return mixed an array of objects, or false if no records were found or an error occured.
+ */
+function similar_tags($text, $limitfrom='' , $limitnum='' ) {
+
+ global $CFG;
+
+ $text = tag_normalize($text);
+
+ $query = "
+ SELECT
+ *
+ FROM
+ {$CFG->prefix}tag t
+ WHERE
+ t.name
+ LIKE
+ '{$text}%'
+ ";
+
+ return get_records_sql($query, $limitfrom , $limitnum);
+}
+
+/**
+ * Returns tags related to a tag
+ *
+ * Related tags of a tag come from two sources:
+ * - manually added related tags, which are tag_instance entries for that tag
+ * - correlated tags, which are a calculated
+ *
+ * @param string $tag_name_or_id is a single **normalized** tag name or the id of a tag
+ * @param int $limitnum return a subset comprising this many records (optional, default is 10)
+ * @return mixed an array of tag objects
+ */
+
+function related_tags($tag_name_or_id, $limitnum=10) {
+
+ $tag_id = tag_id_from_string($tag_name_or_id);
+
+ //gets the manually added related tags
+ $manual_related_tags = get_item_tags('tag',$tag_id);
+ if ($manual_related_tags == false) $manual_related_tags = array();
+
+ //gets the correlated tags
+ $automatic_related_tags = correlated_tags($tag_id);
+ if ($automatic_related_tags == false) $automatic_related_tags = array();
+
+ $related_tags = array_merge($manual_related_tags,$automatic_related_tags);
+
+ return array_slice( object_array_unique($related_tags) , 0 , $limitnum );
+
+
+}
+
+/**
+ * Returns the correlated tags of a tag
+ * The correlated tags are retrieved from the tag_correlation table, which is a caching table.
+ *
+ * @param string $tag_name_or_id is a single **normalized** tag name or the id of a tag
+ * @return mixed an array of tag objects
+ */
+function correlated_tags($tag_name_or_id) {
+
+ $tag_id = tag_id_from_string($tag_name_or_id);
+
+ if (!$tag_correlation = get_record('tag_correlation','tagid',$tag_id)) {
+ return array();
+ }
+
+ $tags_id_csv_with_apos = stripcslashes($tag_correlation->correlatedtags);
+
+ return get_records_select('tag', "id IN ({$tags_id_csv_with_apos})", '', 'id, name, tagtype');
+}
+
+/**
+ * Recalculates tag correlations of all the tags associated with an item
+ * This function could be called whenever the tags associations with an item changes
+ * ( for example when tag_an_item() or untag_an_item() is called )
+ *
+ * @param string $item_type name of the table where the item is stored. Ex: 'user'
+ * @param string $item_id id of the item
+ */
+function update_tag_correlations($item_type, $item_id) {
+
+ $item_tags = get_item_tags($item_type, $item_id);
+
+ foreach ($item_tags as $tag) {
+ cache_correlated_tags($tag->id);
+ }
+}
+
+/**
+ * Calculates and stores the correlated tags of a tag.
+ * The correlations are stored in the 'tag_correlation' table.
+ *
+ * Two tags are correlated if they appear together a lot.
+ * Ex.: Users tagged with "computers" will probably also be tagged with "algorithms".
+ *
+ * The rationale for the 'tag_correlation' table is performance.
+ * It works as a cache for a potentially heavy load query done at the 'tag_instance' table.
+ * So, the 'tag_correlation' table stores redundant information derived from the 'tag_instance' table.
+ *
+ * @param string $tag_name_or_id is a single **normalized** tag name or the id of a tag
+ * @param number $min_correlation cutoff percentage (optional, default is 0.25)
+ * @param int $limitnum return a subset comprising this many records (optional, default is 10)
+ */
+function cache_correlated_tags($tag_name_or_id, $min_correlation=0.25, $limitnum=10) {
+
+ global $CFG;
+
+ $tag_id = tag_id_from_string($tag_name_or_id);
+
+ // query that counts how many times any tag appears together in items
+ // with the tag passed as argument ($tag_id)
+ $query =
+ " SELECT
+ tb.tagid , COUNT(*) nr
+ FROM
+ {$CFG->prefix}tag_instance ta
+ INNER JOIN
+ {$CFG->prefix}tag_instance tb
+ ON
+ ta.itemid = tb.itemid
+ WHERE
+ ta.tagid = {$tag_id}
+ GROUP BY
+ tb.tagid
+ ORDER BY
+ nr DESC";
+
+ $tag_correlations = get_records_sql($query, 0, $limitnum);
+
+ $tags_id_csv_with_apos = "'";
+ $cutoff = $tag_correlations[$tag_id]->nr * $min_correlation;
+
+ foreach($tag_correlations as $correlation) {
+ if($correlation->nr >= $cutoff && $correlation->tagid != $tag_id ){
+ $tags_id_csv_with_apos .= $correlation->tagid."','";
+ }
+ }
+ $tags_id_csv_with_apos = substr($tags_id_csv_with_apos,0,-2);
+
+
+ //saves correlation info in the caching table
+
+ $tag_correlation_obj = get_record('tag_correlation','tagid',$tag_id);
+
+ if ($tag_correlation_obj) {
+ $tag_correlation_obj->correlatedtags = addslashes($tags_id_csv_with_apos);
+ update_record('tag_correlation',$tag_correlation_obj);
+ }
+ else {
+ $tag_correlation_obj = new StdClass;
+ $tag_correlation_obj->tagid = $tag_id;
+ $tag_correlation_obj->correlatedtags = addslashes($tags_id_csv_with_apos);
+ insert_record('tag_correlation',$tag_correlation_obj);
+ }
+
+
+}
+
+/**
+ * This function cleans up the 'tag_instance' table
+ * It removes orphans in 'tag_instances' table
+ *
+ */
+function tag_instance_table_cleanup() {
+
+ global $CFG;
+
+ //get the itemtypes present in the 'tag_instance' table
+ $query = "
+ SELECT
+ DISTINCT(itemtype)
+ FROM
+ {$CFG->prefix}tag_instance
+ ";
+
+ $items_types = get_records_sql($query);
+
+ // for each itemtype, remove tag_instances that are orphans
+ // That is: For a given tag_instance, if in the itemtype table there's no entry with id equal to itemid,
+ // then this tag_instance is an orphan and it will be removed.
+ foreach ($items_types as $type) {
+
+ $query = "
+ {$CFG->prefix}tag_instance.id
+ IN
+ ( SELECT sq1.id
+ FROM
+ (SELECT sq2.*
+ FROM {$CFG->prefix}tag_instance sq2
+ LEFT JOIN {$CFG->prefix}{$type->itemtype} item
+ ON sq2.itemid = item.id
+ WHERE item.id IS NULL
+ AND sq2.itemtype = '{$type->itemtype}')
+ sq1
+ ) ";
+
+ delete_records_select('tag_instance', $query);
+ }
+
+ // remove tag_instances that are orphans because tagid does not correspond to an
+ // existing tag
+ $query = "
+ {$CFG->prefix}tag_instance.id
+ IN
+ (SELECT sq1.id
+ FROM
+ (SELECT sq2.*
+ FROM {$CFG->prefix}tag_instance sq2
+ LEFT JOIN {$CFG->prefix}tag tg
+ ON sq2.tagid = tg.id
+ WHERE tg.id IS NULL )
+ sq1
+ )
+ ";
+
+ delete_records_select('tag_instance', $query);
+}
+
+
+/**
+ * Function that normalizes a tag name
+ *
+ * Ex: tag_normalize('bANAana') -> returns 'banana'
+ * tag_normalize('lots of spaces') -> returns 'lots of spaces'
+ * tag_normalize('%!%!% non alpha numeric %!%!%') -> returns 'non alpha numeric'
+ * tag_normalize('tag one, TAG TWO, TAG three, and anotheR tag')
+ * -> returns 'tag one,tag two,tag three,and another tag'
+ *
+ * @param string $tag_names_csv unnormalized CSV tag names
+ * @return string **normalized** CSV tag names
+ */
+
+function tag_normalize($tag_names_csv) {
+
+ $tags = explode(',', $tag_names_csv);
+
+ if (sizeof($tags) > 1) {
+
+ foreach ($tags as $key => $tag) {
+ $tags[$key] = tag_normalize($tag);
+ }
+
+ return implode(',' , $tags);
+
+ }
+
+ // only one tag was passed
+ else {
+ // value is converted to lowercase and all non-alphanumeric characters are removed
+ //$value = preg_replace('|[^\w ]|i', '', strtolower(trim($tag_names_csv)));
+ $value = preg_replace('|[\!\@\#\$\%\^\&\*\(\)\-\+\=\~\`\.\[\]\{\}\:\;\\\/\<\>\|]|i', '', moodle_strtolower(trim($tag_names_csv)));
+
+ //removes excess white spaces
+ $value = preg_replace('/\s\s+/', ' ', $value);
+
+ return $value;
+ }
+
+}
+
+function is_tag_clean($tag_names_csv) {
+
+}
+
+function tag_flag_inappropriate($tag_names_or_ids_csv){
+
+ $tag_ids_csv = tag_id_from_string($tag_names_or_ids_csv);
+
+ $tag_ids = explode(',', $tag_ids_csv);
+
+ foreach ($tag_ids as $id){
+ $tag = get_record('tag','id',$id, '', '', '', '', 'id,flag');
+
+ $tag->flag++;
+ $tag->timemodified = time();
+
+ update_record('tag', $tag);
+ }
+}
+
+function tag_flag_reset($tag_names_or_ids_csv){
+
+ global $CFG;
+
+ $tag_ids_csv = tag_id_from_string($tag_names_or_ids_csv);
+
+ $tag_ids_csv_with_apos = "'" . str_replace(',', "','", $tag_ids_csv) . "'";
+
+ $timemodified = time();
+
+ $query = "
+ UPDATE
+ {$CFG->prefix}tag tg
+ SET
+ tg.flag = 0,
+ tg.timemodified = {$timemodified}
+ WHERE
+ tg.id
+ IN
+ ({$tag_ids_csv_with_apos})
+ ";
+
+ execute_sql($query, false);
+}
+
+/**
+ * Function that returns comma separated HTML links to the tag pages of the tags passed
+ *
+ * @param array $tag_objects an array of tag objects
+ * @return string CSV, HTML links to tag pages
+ */
+
+function tag_links_csv($tag_objects) {
+
+ global $CFG;
+ $tag_links = '';
+
+ if (empty($tag_objects)) {
+ return '';
+ }
+
+ $systemcontext = get_context_instance(CONTEXT_SYSTEM);
+ $can_manage_tags = has_capability('moodle/tag:manage', $systemcontext);
+
+ foreach ($tag_objects as $tag){
+ //highlight tags that have been flagged as inappropriate for those who can manage them
+ $tagname = $tag->name;
+ if ($tag->flag > 0 && $can_manage_tags) {
+ $tagname = '<span class="flagged-tag">' . $tagname . '</span>';
+ }
+ $tag_links .= ' <a href="'.$CFG->wwwroot.'/tag/index.php?id='.$tag->id.'">'.$tagname.'</a>,';
+ }
+
+ return rtrim($tag_links, ',');
+}
+
+/**
+ * Function that returns comma separated names of the tags passed
+ * Example of string that might be returned: 'history, wars, greek history'
+ *
+ * @param array $tag_objects
+ * @return string CSV tag names
+ */
+
+function tag_names_csv($tag_objects) {
+
+ if (empty($tag_objects)) {
+ return '';
+ }
+
+ $tags = array();
+
+ foreach ($tag_objects as $tag){
+ $tags[] = $tag->name;
+ }
+
+ return implode(',', $tags);
+}
+
+
+/**
+ * Returns a number of random tags, ordered by their popularity
+ *
+ * @param int $nr_of_tags number of random tags to be returned
+ * @param unknown_type $tag_type
+ * @return mixed an array of tag objects with the following fields: id, name and count
+ */
+function rand_tags_count($nr_of_tags=20, $tag_type = 'default') {
+
+ global $CFG;
+
+ if (!$tags = get_all_tags($tag_type)) {
+ return array();
+ }
+
+ if(sizeof($tags) < $nr_of_tags) {
+ $nr_of_tags = sizeof($tags);
+ }
+
+ $rndtags = array_rand($tags, $nr_of_tags);
+
+ $tags_id_csv_with_apos = "'";
+ foreach($rndtags as $tagid) {
+ $tags_id_csv_with_apos .= $tags[$tagid]->id . "','";
+ }
+ $tags_id_csv_with_apos = substr($tags_id_csv_with_apos,0,-2);
+
+
+ $query = "
+ SELECT
+ tg.id, tg.name, COUNT(ti.id) AS count, tg.flag
+ FROM
+ {$CFG->prefix}tag_instance ti
+ INNER JOIN
+ {$CFG->prefix}tag tg
+ ON
+ tg.id = ti.tagid
+ WHERE
+ ti.tagid
+ IN
+ ({$tags_id_csv_with_apos})
+ GROUP BY
+ tagid
+ ORDER BY
+ count
+ ASC";
+
+ return get_records_sql($query);
+
+
+}
+
+/*-------------------- Printing functions -------------------- */
+
+/**
+ * Prints a box that contains the management links of a tag
+ *
+ * @param $tag_object
+ */
+
+function print_tag_management_box($tag_object) {
+
+ global $USER, $CFG;
+
+ $tagname = /*ucwords*/($tag_object->name);
+
+ print_box_start('box','tag-management-box');
+
+ $systemcontext = get_context_instance(CONTEXT_SYSTEM);
+
+ $addtaglink = '';
+ if ( has_capability('moodle/tag:manage',$systemcontext) ) {
+ $manage_link = "<a href=\"{$CFG->wwwroot}/tag/manage.php\">" . get_string('managetags', 'tag') . "</a>" ;
+ echo $manage_link .' | ';
+ }
+
+ // if the user is not tagged with the $tag_object tag, a link "add blahblah to my interests" will appear
+ if( !is_item_tagged_with('user', $USER->id, $tag_object->id )) {
+ $addtaglink = '<a href="' . $CFG->wwwroot . '/user/tag.php?action=addinterest&id='. $tag_object->id .'">';
+ $addtaglink .= get_string('addtagtomyinterests','tag',$tagname). '</a>';
+ echo $addtaglink .' | ';
+ }
+
+ // only people with moodle/tag:edittags capability may edit the tag description
+ if ( has_capability('moodle/tag:edit',$systemcontext) && is_item_tagged_with('user', $USER->id, $tag_object->id ) ) {
+ echo ' <a href="'. $CFG->wwwroot . '/tag/edit.php?id='.$tag_object->id .'">'.get_string('edittag', 'tag').'</a> | ';
+ }
+
+ // flag as inappropriate link
+ $flagtaglink = '<a href="' . $CFG->wwwroot . '/user/tag.php?action=flaginappropriate&id='. $tag_object->id .'">';
+ $flagtaglink .= get_string('flagasinappropriate','tag',$tagname). '</a>';
+ echo $flagtaglink;
+
+ print_box_end();
+
+}
+
+/**
+ * Prints a box with the description of a tag and its related tags
+ *
+ * @param unknown_type $tag_object
+ */
+
+function print_tag_description_box($tag_object) {
+
+ global $USER, $CFG;
+
+ $tagname = /*ucwords*/($tag_object->name);
+ $related_tags = related_tags($tag_object->id); //get_item_tags('tags',$tag_object->id);
+
+
+ print_box_start('generalbox', 'tag-description');
+
+ if (!empty($tag_object->description)) {
+ echo format_text($tag_object->description, $tag_object->descriptionformat );
+ }
+ else {
+ echo format_text(get_string('thistaghasnodesc','tag'));
+ }
+
+
+ if ($related_tags) {
+ echo '<br/><b>'.get_string('relatedtags','tag').': </b>' . tag_links_csv($related_tags);
+ }
+
+ print_box_end();
+}
+
+/**
+ * Prints a table of the users tagged with the tag passed as argument
+ *
+ * @param $tag_object
+ * @param int $users_per_row number of users per row to display
+ * @param int $limitfrom prints users starting at this point (optional, required if $limitnum is set).
+ * @param int $limitnum prints this many users (optional, required if $limitfrom is set).
+ */
+
+function print_tagged_users_table($tag_object, $users_per_row='5', $limitfrom='' , $limitnum='') {
+
+ //List of users with this tag
+ $userlist = array_values( get_items_tagged_with(
+ 'user',
+ $tag_object->id,
+ 'lastaccess DESC' ,
+ 'id, firstname, lastname, picture',
+ $limitfrom,
+ $limitnum) );
+
+ //user table box
+ print_box_start('generalbox', 'tag-user-table');
+
+ print_user_table($userlist, $users_per_row);
+
+ print_box_end();
+ //end table box
+
+
+
+}
+
+/**
+ * Prints a table of users
+ *
+ * @param array $userlist an array of user objects
+ * @param int $users_per_row number of users per row to display
+ */
+function print_user_table($userlist, $users_per_row='5') {
+
+ $nrofrows = ceil( count($userlist) / $users_per_row );
+ for($row = 0; $row < $nrofrows; $row++){
+
+ //table row box
+ print_box_start('user-table-row', 'row_'.$row);
+
+ for($col = 0; ($col < $users_per_row) ; $col++ ) {
+
+ $index = $row * $users_per_row + $col;
+
+ if ($index < count($userlist) ) {
+
+ print_user_box( $userlist[$index] );
+
+ }
+
+ }
+
+ print_box_end();
+ //end table row box
+
+ }
+
+}
+
+/**
+ * Prints an individual user box
+ *
+ * @param $user user object (contains the following fields: id, firstname, lastname and picture)
+ */
+function print_user_box($user) {
+
+ global $CFG;
+
+ $usercontext = get_context_instance(CONTEXT_USER, $user->id);
+
+ $profilelink = '';
+ if ( has_capability('moodle/user:viewdetails', $usercontext) ) {
+ $profilelink = $CFG->wwwroot.'/user/view.php?id='.$user->id;
+ }
+
+ print_box_start('user-box', $user->id);
+
+ if (!empty($profilelink)) echo '<a href="'.$profilelink.'">';
+
+ //print user image
+ if ($user->picture) {
+ echo '<img class="user-image" src="'. $CFG->wwwroot .'/user/pix.php/'. $user->id .'/f1.jpg"'.'/>';
+ }
+ else {
+ echo '<img class="user-image" src="'. $CFG->wwwroot .'/pix/u/f1.png"'.'/>';
+ }
+
+ echo '<br/>';
+
+ if (!empty($profilelink)) echo '</a>';
+
+ $fullname = fullname($user);
+ //truncate name if it's too big
+ if (strlen($fullname) > 26) $fullname = substr($fullname,0,26) . '...';
+
+ echo '<strong>' . $fullname . '</strong>';
+
+ print_box_end();
+
+}
+
+/**
+ * Prints the tag search box
+ *
+ */
+function print_tag_search_box($search='') {
+
+ global $CFG;
+
+ print_box_start('','tag-search-box');
+
+ echo '<form action="'.$CFG->wwwroot.'/tag/search.php" style="display:inline">';
+ echo '<div>';
+ echo '<input id="searchform_search" name="query" type="text" size="40" />';
+ echo '<button id="searchform_button" type="submit">'. get_string('search', 'tag') .'</button><br />';
+ echo '</div>';
+ echo '</form>';
+
+ print_box_end();
+}
+
+/**
+ * Prints the tag search results
+ *
+ * @param string $query text that tag names will be matched against
+ * @param int $page current page
+ * @param int $perpage nr of users displayed per page
+ */
+function print_tag_search_results($query, $page, $perpage) {
+
+ global $CFG, $USER;
+
+ $count = sizeof( search_tags($query,false) );
+ $tags = array_values(search_tags($query, true, $page * $perpage , $perpage));
+
+ $baseurl = $CFG->wwwroot.'/tag/search.php?query=' . $query;
+
+ // link "Add $query to my interests"
+ $addtaglink = '';
+ if( !is_item_tagged_with('user', $USER->id, $query )) {
+ $addtaglink = '<a href="' . $CFG->wwwroot . '/user/tag.php?action=addinterest&name='. $query .'">';
+ $addtaglink .= get_string('addtagtomyinterests','tag',$query). '</a>';
+ }
+
+
+ if($tags) { // there are results to display!!
+
+ print_heading(get_string('searchresultsfor', 'tag') . " \"{$query}\" : {$count}", '', 3);
+
+ //print a link "Add $query to my interests"
+ if (!empty($addtaglink)) {
+ print_box($addtaglink,'box','tag-management-box');
+ }
+
+ $nr_of_lis_per_ul = 6;
+ $nr_of_uls = ceil( sizeof($tags) / $nr_of_lis_per_ul);
+
+ echo '<ul id="tag-search-results">';
+ for($i = 0; $i < $nr_of_uls; $i++) {
+ echo '<li>';
+ foreach (array_slice($tags, $i * $nr_of_lis_per_ul, $nr_of_lis_per_ul ) as $tag) {
+ $tag_link = ' <a href="'.$CFG->wwwroot.'/tag/index.php?id='.$tag->id.'">'.$tag->name.'</a>';
+ echo '•' . $tag_link . '<br/>';
+ }
+ echo '</li>';
+ }
+ echo '</ul>';
+ echo '<div> </div>'; // <-- small layout hack in order to look good in Firefox
+
+ print_paging_bar($count, $page, $perpage, $baseurl.'&', 'page');
+ }
+ else { //no results were found!!
+
+ print_heading(get_string('noresultsfor', 'tag') . " \"{$query}\" ", '', 3);
+
+ //print a link "Add $query to my interests"
+ if (!empty($addtaglink)) {
+ print_box($addtaglink,'box','tag-management-box');
+ }
+
+ }
+
+
+}
+
+/**
+ * Prints a tag cloud
+ *
+ * @param int $nr_of_tags number of tags in the cloud
+ * @param int $max_size maximum text size, in percentage
+ * @param int $min_size minimum text size, in percentage
+ */
+function print_tag_cloud($tagcloud, $shuffle=true, $max_size=180, $min_size=80) {
+
+ global $CFG;
+
+ if (empty($tagcloud)) {
+ return;
+ }
+
+ if ( $shuffle ) {
+ shuffle($tagcloud);
+ }
+
+ $count = array();
+ foreach ($tagcloud as $key => $value){
+ if(!empty($value->count)) {
+ $count[$key] = log10($value->count);
+ }
+ else{
+ $count[$key] = 0;
+ }
+ }
+
+ $max = max($count);
+ $min = min($count);
+
+ $spread = $max - $min;
+ if (0 == $spread) { // we don't want to divide by zero
+ $spread = 1;
+ }
+
+ $step = ($max_size - $min_size)/($spread);
+
+ $systemcontext = get_context_instance(CONTEXT_SYSTEM);
+ $can_manage_tags = has_capability('moodle/tag:manage', $systemcontext);
+
+ //prints the tag cloud
+ echo '<ul id="tag-cloud-list">';
+ foreach ($tagcloud as $key => $tag) {
+
+ $size = $min_size + ((log10($tag->count) - $min) * $step);
+ $size = ceil($size);
+
+ $style = 'style="font-size: '.$size.'%"';
+ $title = 'title="'.s(get_string('thingstaggedwith','tag', $tag)).'"';
+ $href = 'href="'.$CFG->wwwroot.'/tag/index.php?id='.$tag->id.'"';
+
+ //highlight tags that have been flagged as inappropriate for those who can manage them
+ $tagname = $tag->name;
+ if ($tag->flag > 0 && $can_manage_tags) {
+ $tagname = '<span class="flagged-tag">' . $tag->name . '</span>';
+ }
+
+ $tag_link = '<li><a '.$href.' '.$title.' '. $style .'>'.$tagname.'</a></li> ';
+
+ echo $tag_link;
+
+ }
+ echo '</ul>';
+
+}
+
+function print_tag_management_list($perpage='100') {
+
+ global $CFG, $USER;
+ require_once($CFG->libdir.'/tablelib.php');
+
+ //setup table
+ $tablecolumns = array('name', 'owner', 'count', 'flag', 'timemodified', '');
+ $tableheaders = array( get_string('name' , 'tag'),
+ get_string('owner','tag'),
+ get_string('count','tag'),
+ get_string('flag','tag'),
+ get_string('timemodified','tag'),
+ get_string('select', 'tag')
+ );
+
+ $table = new flexible_table('tag-management-list-'.$USER->id);
+
+ $baseurl = $CFG->wwwroot.'/tag/manage.php';
+
+ $table->define_columns($tablecolumns);
+ $table->define_headers($tableheaders);
+ $table->define_baseurl($baseurl);
+
+ $table->sortable(true, 'flag', SORT_DESC);
+
+ $table->set_attribute('cellspacing', '0');
+ $table->set_attribute('id', 'tag-management-list');
+ $table->set_attribute('class', 'generaltable generalbox');
+
+ $table->set_control_variables(array(
+ TABLE_VAR_SORT => 'ssort',
+ TABLE_VAR_HIDE => 'shide',
+ TABLE_VAR_SHOW => 'sshow',
+ TABLE_VAR_IFIRST => 'sifirst',
+ TABLE_VAR_ILAST => 'silast',
+ TABLE_VAR_PAGE => 'spage'
+ ));
+
+ $table->setup();
+
+ if ($table->get_sql_sort()) {
+ $sort = ' ORDER BY '.$table->get_sql_sort();
+ } else {
+ $sort = '';
+ }
+
+ if ($table->get_sql_where()) {
+ $where = 'WHERE '.$table->get_sql_where();
+ } else {
+ $where = '';
+ }
+
+ $query = "
+ SELECT
+ tg.id, tg.name, COUNT(ti.id) AS count, u.id AS owner, tg.flag, tg.timemodified
+ FROM
+ {$CFG->prefix}tag_instance ti
+ RIGHT JOIN
+ {$CFG->prefix}tag tg
+ ON
+ tg.id = ti.tagid
+ LEFT JOIN
+ {$CFG->prefix}user u
+ ON
+ tg.userid = u.id
+ {$where}
+ GROUP BY
+ tg.id
+ {$sort}
+ ";
+
+ $totalcount = count_records('tag');
+
+ $table->initialbars($totalcount > $perpage);
+ $table->pagesize($perpage, $totalcount);
+
+
+ echo '<form id="tag-management-form" method="post" action="'.$CFG->wwwroot.'/tag/manage.php">';
+
+ //retrieve tags from DB
+ if ($tagrecords = get_records_sql($query, $table->get_page_start(), $table->get_page_size())) {
+
+ $taglist = array_values($tagrecords);
+
+ //print_tag_cloud(array_values(get_records_sql($query)), false);
+
+ //populate table with data
+ foreach ($taglist as $tag ){
+
+ $name = '<a href="'.$CFG->wwwroot.'/tag/index.php?id='.$tag->id.'">'.$tag->name.'</a>';
+ $owner = '<a href="'.$CFG->wwwroot.'/user/view.php?id='.$tag->owner.'">' . $tag->owner . '</a>';
+ $count = $tag->count;
+ $flag = $tag->flag;
+ $timemodified = format_time(time() - $tag->timemodified);
+ $checkbox = '<input type="checkbox" name="tagschecked[]" value="'.$tag->id.'" />';
+
+ //if the tag if flagged, highlight it
+ if ($tag->flag > 0) {
+ $name = '<span class="flagged-tag">' . $name . '</span>';
+ $owner = '<span class="flagged-tag">' . $owner . '</span>';
+ $count = '<span class="flagged-tag">' . $count . '</span>';
+ $flag = '<span class="flagged-tag">' . $flag . '</span>';
+ $timemodified = '<span class="flagged-tag">' . $timemodified . '</span>';
+ }
+
+ $data = array($name , $owner ,$count ,$flag, $timemodified, $checkbox);
+
+ $table->add_data($data);
+ }
+
+
+ echo '<input type="button" onclick="checkall()" value="'.get_string('selectall').'" /> ';
+ echo '<input type="button" onclick="checknone()" value="'.get_string('deselectall').'" /> ';
+ echo '<br/><br/>';
+ echo '<select id="menuformaction" name="action">
+ <option value="" selected="selected">With selected tags...</option>
+ <option value="reset">'. get_string('resetflag', 'tag') .'</option>
+ <option value="delete">'. get_string('delete', 'tag') .'</option>
+ </select>';
+
+ echo '<button id="tag-management-submit" type="submit">'. get_string('ok') .'</button>';
+
+ }
+
+ $table->print_html();
+
+ echo '</form>';
+}
+
+?>
projects / moodle.git / commitdiff