You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

1772 lines
72 KiB

<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
/**
* Contains class core_tag_tag
*
* @package core_tag
* @copyright 2015 Marina Glancy
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
defined('MOODLE_INTERNAL') || die();
/**
* Represents one tag and also contains lots of useful tag-related methods as static functions.
*
* Tags can be added to any database records.
* $itemtype refers to the DB table name
* $itemid refers to id field in this DB table
* $component is the component that is responsible for the tag instance
* $context is the affected context
*
* BASIC INSTRUCTIONS :
* - to "tag a blog post" (for example):
* core_tag_tag::set_item_tags('post', 'core', $blogpost->id, $context, $arrayoftags);
*
* - to "remove all the tags on a blog post":
* core_tag_tag::remove_all_item_tags('post', 'core', $blogpost->id);
*
* set_item_tags() will create tags that do not exist yet.
*
* @property-read int $id
* @property-read string $name
* @property-read string $rawname
* @property-read int $tagcollid
* @property-read int $userid
* @property-read int $isstandard
* @property-read string $description
* @property-read int $descriptionformat
* @property-read int $flag 0 if not flagged or positive integer if flagged
* @property-read int $timemodified
*
* @package core_tag
* @copyright 2015 Marina Glancy
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
class core_tag_tag {
/** @var stdClass data about the tag */
protected $record = null;
/** @var int indicates that both standard and not standard tags can be used (or should be returned) */
const BOTH_STANDARD_AND_NOT = 0;
/** @var int indicates that only standard tags can be used (or must be returned) */
const STANDARD_ONLY = 1;
/** @var int indicates that only non-standard tags should be returned - this does not really have use cases, left for BC */
const NOT_STANDARD_ONLY = -1;
/** @var int option to hide standard tags when editing item tags */
const HIDE_STANDARD = 2;
/**
* Constructor. Use functions get(), get_by_name(), etc.
*
* @param stdClass $record
*/
protected function __construct($record) {
if (empty($record->id)) {
throw new coding_exeption("Record must contain at least field 'id'");
}
$this->record = $record;
}
/**
* Magic getter
*
* @param string $name
* @return mixed
*/
public function __get($name) {
return $this->record->$name;
}
/**
* Magic isset method
*
* @param string $name
* @return bool
*/
public function __isset($name) {
return isset($this->record->$name);
}
/**
* Converts to object
*
* @return stdClass
*/
public function to_object() {
return fullclone($this->record);
}
/**
* Returns tag name ready to be displayed
*
* @param bool $ashtml (default true) if true will return htmlspecialchars encoded string
* @return string
*/
public function get_display_name($ashtml = true) {
return static::make_display_name($this->record, $ashtml);
}
/**
* Prepares tag name ready to be displayed
*
* @param stdClass|core_tag_tag $tag record from db table tag, must contain properties name and rawname
* @param bool $ashtml (default true) if true will return htmlspecialchars encoded string
* @return string
*/
public static function make_display_name($tag, $ashtml = true) {
global $CFG;
if (empty($CFG->keeptagnamecase)) {
// This is the normalized tag name.
$tagname = core_text::strtotitle($tag->name);
} else {
// Original casing of the tag name.
$tagname = $tag->rawname;
}
// Clean up a bit just in case the rules change again.
$tagname = clean_param($tagname, PARAM_TAG);
return $ashtml ? htmlspecialchars($tagname) : $tagname;
}
/**
* Adds one or more tag in the database. This function should not be called directly : you should
* use tag_set.
*
* @param int $tagcollid
* @param string|array $tags one tag, or an array of tags, to be created
* @param bool $isstandard type of tag to be created. A standard tag is kept even if there are no records tagged with it.
* @return array tag objects indexed by their lowercase normalized names. Any boolean false in the array
* indicates an error while adding the tag.
*/
protected static function add($tagcollid, $tags, $isstandard = false) {
global $USER, $DB;
$tagobject = new stdClass();
$tagobject->isstandard = $isstandard ? 1 : 0;
$tagobject->userid = $USER->id;
$tagobject->timemodified = time();
$tagobject->tagcollid = $tagcollid;
$rv = array();
foreach ($tags as $veryrawname) {
$rawname = clean_param($veryrawname, PARAM_TAG);
if (!$rawname) {
$rv[$rawname] = false;
} else {
$obj = (object)(array)$tagobject;
$obj->rawname = $rawname;
$obj->name = core_text::strtolower($rawname);
$obj->id = $DB->insert_record('tag', $obj);
$rv[$obj->name] = new static($obj);
\core\event\tag_created::create_from_tag($rv[$obj->name])->trigger();
}
}
return $rv;
}
/**
* Simple function to just return a single tag object by its id
*
* @param int $id
* @param string $returnfields which fields do we want returned from table {tag}.
* Default value is 'id,name,rawname,tagcollid',
* specify '*' to include all fields.
* @param int $strictness IGNORE_MISSING means compatible mode, false returned if record not found, debug message if more found;
* IGNORE_MULTIPLE means return first, ignore multiple records found(not recommended);
* MUST_EXIST means throw exception if no record or multiple records found
* @return core_tag_tag|false tag object
*/
public static function get($id, $returnfields = 'id, name, rawname, tagcollid', $strictness = IGNORE_MISSING) {
global $DB;
$record = $DB->get_record('tag', array('id' => $id), $returnfields, $strictness);
if ($record) {
return new static($record);
}
return false;
}
/**
* Simple function to just return an array of tag objects by their ids
*
* @param int[] $ids
* @param string $returnfields which fields do we want returned from table {tag}.
* Default value is 'id,name,rawname,tagcollid',
* specify '*' to include all fields.
* @return core_tag_tag[] array of retrieved tags
*/
public static function get_bulk($ids, $returnfields = 'id, name, rawname, tagcollid') {
global $DB;
$result = array();
if (empty($ids)) {
return $result;
}
list($sql, $params) = $DB->get_in_or_equal($ids);
$records = $DB->get_records_select('tag', 'id '.$sql, $params, '', $returnfields);
foreach ($records as $record) {
$result[$record->id] = new static($record);
}
return $result;
}
/**
* Simple function to just return a single tag object by tagcollid and name
*
* @param int $tagcollid tag collection to use,
* if 0 is given we will try to guess the tag collection and return the first match
* @param string $name tag name
* @param string $returnfields which fields do we want returned. This is a comma separated string
* containing any combination of 'id', 'name', 'rawname', 'tagcollid' or '*' to include all fields.
* @param int $strictness IGNORE_MISSING means compatible mode, false returned if record not found, debug message if more found;
* IGNORE_MULTIPLE means return first, ignore multiple records found(not recommended);
* MUST_EXIST means throw exception if no record or multiple records found
* @return core_tag_tag|false tag object
*/
public static function get_by_name($tagcollid, $name, $returnfields='id, name, rawname, tagcollid',
$strictness = IGNORE_MISSING) {
global $DB;
if ($tagcollid == 0) {
$tags = static::guess_by_name($name, $returnfields);
if ($tags) {
$tag = reset($tags);
return $tag;
} else if ($strictness == MUST_EXIST) {
throw new dml_missing_record_exception('tag', 'name=?', array($name));
}
return false;
}
$name = core_text::strtolower($name); // To cope with input that might just be wrong case.
$params = array('name' => $name, 'tagcollid' => $tagcollid);
$record = $DB->get_record('tag', $params, $returnfields, $strictness);
if ($record) {
return new static($record);
}
return false;
}
/**
* Looking in all tag collections for the tag with the given name
*
* @param string $name tag name
* @param string $returnfields
* @return array array of core_tag_tag instances
*/
public static function guess_by_name($name, $returnfields='id, name, rawname, tagcollid') {
global $DB;
if (empty($name)) {
return array();
}
$tagcolls = core_tag_collection::get_collections();
list($sql, $params) = $DB->get_in_or_equal(array_keys($tagcolls), SQL_PARAMS_NAMED);
$params['name'] = core_text::strtolower($name);
$tags = $DB->get_records_select('tag', 'name = :name AND tagcollid ' . $sql, $params, '', $returnfields);
if (count($tags) > 1) {
// Sort in the same order as tag collections.
$tagcolls = core_tag_collection::get_collections();
uasort($tags, function($a, $b) use ($tagcolls) {
return $tagcolls[$a->tagcollid]->sortorder < $tagcolls[$b->tagcollid]->sortorder ? -1 : 1;
});
}
$rv = array();
foreach ($tags as $id => $tag) {
$rv[$id] = new static($tag);
}
return $rv;
}
/**
* Returns the list of tag objects by tag collection id and the list of tag names
*
* @param int $tagcollid
* @param array $tags array of tags to look for
* @param string $returnfields list of DB fields to return, must contain 'id', 'name' and 'rawname'
* @return array tag-indexed array of objects. No value for a key means the tag wasn't found.
*/
public static function get_by_name_bulk($tagcollid, $tags, $returnfields = 'id, name, rawname, tagcollid') {
global $DB;
if (empty($tags)) {
return array();
}
$cleantags = self::normalize(self::normalize($tags, false)); // Format: rawname => normalised name.
list($namesql, $params) = $DB->get_in_or_equal(array_values($cleantags));
array_unshift($params, $tagcollid);
$recordset = $DB->get_recordset_sql("SELECT $returnfields FROM {tag} WHERE tagcollid = ? AND name $namesql", $params);
$result = array_fill_keys($cleantags, null);
foreach ($recordset as $record) {
$result[$record->name] = new static($record);
}
$recordset->close();
return $result;
}
/**
* Function that normalizes a list of tag names.
*
* @param array $rawtags array of tags
* @param bool $tolowercase convert to lower case?
* @return array lowercased normalized tags, indexed by the normalized tag, in the same order as the original array.
* (Eg: 'Banana' => 'banana').
*/
public static function normalize($rawtags, $tolowercase = true) {
$result = array();
foreach ($rawtags as $rawtag) {
$rawtag = trim($rawtag);
if (strval($rawtag) !== '') {
$clean = clean_param($rawtag, PARAM_TAG);
if ($tolowercase) {
$result[$rawtag] = core_text::strtolower($clean);
} else {
$result[$rawtag] = $clean;
}
}
}
return $result;
}
/**
* Retrieves tags and/or creates them if do not exist yet
*
* @param int $tagcollid
* @param array $tags array of raw tag names, do not have to be normalised
* @param bool $isstandard create as standard tag (default false)
* @return core_tag_tag[] array of tag objects indexed with lowercase normalised tag name
*/
public static function create_if_missing($tagcollid, $tags, $isstandard = false) {
$cleantags = self::normalize(array_filter(self::normalize($tags, false))); // Array rawname => normalised name .
$result = static::get_by_name_bulk($tagcollid, $tags, '*');
$existing = array_filter($result);
$missing = array_diff_key(array_flip($cleantags), $existing); // Array normalised name => rawname.
if ($missing) {
$newtags = static::add($tagcollid, array_values($missing), $isstandard);
foreach ($newtags as $tag) {
$result[$tag->name] = $tag;
}
}
return $result;
}
/**
* Creates a URL to view a tag
*
* @param int $tagcollid
* @param string $name
* @param int $exclusivemode
* @param int $fromctx context id where this tag cloud is displayed
* @param int $ctx context id for tag view link
* @param int $rec recursive argument for tag view link
* @return \moodle_url
*/
public static function make_url($tagcollid, $name, $exclusivemode = 0, $fromctx = 0, $ctx = 0, $rec = 1) {
$coll = core_tag_collection::get_by_id($tagcollid);
if (!empty($coll->customurl)) {
$url = '/' . ltrim(trim($coll->customurl), '/');
} else {
$url = '/tag/index.php';
}
$params = array('tc' => $tagcollid, 'tag' => $name);
if ($exclusivemode) {
$params['excl'] = 1;
}
if ($fromctx) {
$params['from'] = $fromctx;
}
if ($ctx) {
$params['ctx'] = $ctx;
}
if (!$rec) {
$params['rec'] = 0;
}
return new moodle_url($url, $params);
}
/**
* Returns URL to view the tag
*
* @param int $exclusivemode
* @param int $fromctx context id where this tag cloud is displayed
* @param int $ctx context id for tag view link
* @param int $rec recursive argument for tag view link
* @return \moodle_url
*/
public function get_view_url($exclusivemode = 0, $fromctx = 0, $ctx = 0, $rec = 1) {
return static::make_url($this->record->tagcollid, $this->record->rawname,
$exclusivemode, $fromctx, $ctx, $rec);
}
/**
* Validates that the required fields were retrieved and retrieves them if missing
*
* @param array $list array of the fields that need to be validated
* @param string $caller name of the function that requested it, for the debugging message
*/
protected function ensure_fields_exist($list, $caller) {
global $DB;
$missing = array_diff($list, array_keys((array)$this->record));
if ($missing) {
debugging('core_tag_tag::' . $caller . '() must be called on fully retrieved tag object. Missing fields: '.
join(', ', $missing), DEBUG_DEVELOPER);
$this->record = $DB->get_record('tag', array('id' => $this->record->id), '*', MUST_EXIST);
}
}
/**
* Deletes the tag instance given the record from tag_instance DB table
*
* @param stdClass $taginstance
* @param bool $fullobject whether $taginstance contains all fields from DB table tag_instance
* (in this case it is safe to add a record snapshot to the event)
* @return bool
*/
protected function delete_instance_as_record($taginstance, $fullobject = false) {
global $DB;
$this->ensure_fields_exist(array('name', 'rawname', 'isstandard'), 'delete_instance_as_record');
$DB->delete_records('tag_instance', array('id' => $taginstance->id));
// We can not fire an event with 'null' as the contextid.
if (is_null($taginstance->contextid)) {
$taginstance->contextid = context_system::instance()->id;
}
// Trigger tag removed event.
$taginstance->tagid = $this->id;
\core\event\tag_removed::create_from_tag_instance($taginstance, $this->name, $this->rawname, $fullobject)->trigger();
// If there are no other instances of the tag then consider deleting the tag as well.
if (!$this->isstandard) {
if (!$DB->record_exists('tag_instance', array('tagid' => $this->id))) {
self::delete_tags($this->id);
}
}
return true;
}
/**
* Delete one instance of a tag. If the last instance was deleted, it will also delete the tag, unless it is standard.
*
* @param string $component component responsible for tagging. For BC it can be empty but in this case the
* query will be slow because DB index will not be used.
* @param string $itemtype the type of the record for which to remove the instance
* @param int $itemid the id of the record for which to remove the instance
* @param int $tiuserid tag instance user id, only needed for tag areas with user tagging (such as core/course)
*/
protected function delete_instance($component, $itemtype, $itemid, $tiuserid = 0) {
global $DB;
$params = array('tagid' => $this->id,
'itemtype' => $itemtype, 'itemid' => $itemid);
if ($tiuserid) {
$params['tiuserid'] = $tiuserid;
}
if ($component) {
$params['component'] = $component;
}
$taginstance = $DB->get_record('tag_instance', $params);
if (!$taginstance) {
return;
}
$this->delete_instance_as_record($taginstance, true);
}
/**
* Bulk delete all tag instances.
*
* @param stdClass[] $taginstances A list of tag_instance records to delete. Each
* record must also contain the name and rawname
* columns from the related tag record.
*/
public static function delete_instances_as_record(array $taginstances) {
global $DB;
if (empty($taginstances)) {
return;
}
$taginstanceids = array_map(function($taginstance) {
return $taginstance->id;
}, $taginstances);
// Now remove all the tag instances.
$DB->delete_records_list('tag_instance', 'id', $taginstanceids);
// Save the system context in case the 'contextid' column in the 'tag_instance' table is null.
$syscontextid = context_system::instance()->id;
// Loop through the tag instances and fire an 'tag_removed' event.
foreach ($taginstances as $taginstance) {
// We can not fire an event with 'null' as the contextid.
if (is_null($taginstance->contextid)) {
$taginstance->contextid = $syscontextid;
}
// Trigger tag removed event.
\core\event\tag_removed::create_from_tag_instance($taginstance, $taginstance->name,
$taginstance->rawname, true)->trigger();
}
}
/**
* Bulk delete all tag instances by tag id.
*
* @param int[] $taginstanceids List of tag instance ids to be deleted.
*/
public static function delete_instances_by_id(array $taginstanceids) {
global $DB;
if (empty($taginstanceids)) {
return;
}
list($idsql, $params) = $DB->get_in_or_equal($taginstanceids);
$sql = "SELECT ti.*, t.name, t.rawname, t.isstandard
FROM {tag_instance} ti
JOIN {tag} t
ON ti.tagid = t.id
WHERE ti.id {$idsql}";
if ($taginstances = $DB->get_records_sql($sql, $params)) {
static::delete_instances_as_record($taginstances);
}
}
/**
* Bulk delete all tag instances for a component or tag area
*
* @param string $component
* @param string $itemtype (optional)
* @param int $contextid (optional)
*/
public static function delete_instances($component, $itemtype = null, $contextid = null) {
global $DB;
$sql = "SELECT ti.*, t.name, t.rawname, t.isstandard
FROM {tag_instance} ti
JOIN {tag} t
ON ti.tagid = t.id
WHERE ti.component = :component";
$params = array('component' => $component);
if (!is_null($contextid)) {
$sql .= " AND ti.contextid = :contextid";
$params['contextid'] = $contextid;
}
if (!is_null($itemtype)) {
$sql .= " AND ti.itemtype = :itemtype";
$params['itemtype'] = $itemtype;
}
if ($taginstances = $DB->get_records_sql($sql, $params)) {
static::delete_instances_as_record($taginstances);
}
}
/**
* Adds a tag instance
*
* @param string $component
* @param string $itemtype
* @param string $itemid
* @param context $context
* @param int $ordering
* @param int $tiuserid tag instance user id, only needed for tag areas with user tagging (such as core/course)
* @return int id of tag_instance
*/
protected function add_instance($component, $itemtype, $itemid, context $context, $ordering, $tiuserid = 0) {
global $DB;
$this->ensure_fields_exist(array('name', 'rawname'), 'add_instance');
$taginstance = new stdClass;
$taginstance->tagid = $this->id;
$taginstance->component = $component ? $component : '';
$taginstance->itemid = $itemid;
$taginstance->itemtype = $itemtype;
$taginstance->contextid = $context->id;
$taginstance->ordering = $ordering;
$taginstance->timecreated = time();
$taginstance->timemodified = $taginstance->timecreated;
$taginstance->tiuserid = $tiuserid;
$taginstance->id = $DB->insert_record('tag_instance', $taginstance);
// Trigger tag added event.
\core\event\tag_added::create_from_tag_instance($taginstance, $this->name, $this->rawname, true)->trigger();
return $taginstance->id;
}
/**
* Updates the ordering on tag instance
*
* @param int $instanceid
* @param int $ordering
*/
protected function update_instance_ordering($instanceid, $ordering) {
global $DB;
$data = new stdClass();
$data->id = $instanceid;
$data->ordering = $ordering;
$data->timemodified = time();
$DB->update_record('tag_instance', $data);
}
/**
* Get the array of core_tag_tag objects associated with a list of items.
*
* Use {@link core_tag_tag::get_item_tags_array()} if you wish to get the same data as simple array.
*
* @param string $component component responsible for tagging. For BC it can be empty but in this case the
* query will be slow because DB index will not be used.
* @param string $itemtype type of the tagged item
* @param int[] $itemids
* @param int $standardonly wether to return only standard tags or any
* @param int $tiuserid tag instance user id, only needed for tag areas with user tagging
* @return core_tag_tag[] each object contains additional fields taginstanceid, taginstancecontextid and ordering
*/
public static function get_items_tags($component, $itemtype, $itemids, $standardonly = self::BOTH_STANDARD_AND_NOT,
$tiuserid = 0) {
global $DB;
if (static::is_enabled($component, $itemtype) === false) {
// Tagging area is properly defined but not enabled - return empty array.
return array();
}
if (empty($itemids)) {
return array();
}
$standardonly = (int)$standardonly; // In case somebody passed bool.
list($idsql, $params) = $DB->get_in_or_equal($itemids, SQL_PARAMS_NAMED);
// Note: if the fields in this query are changed, you need to do the same changes in core_tag_tag::get_correlated_tags().
$sql = "SELECT ti.id AS taginstanceid, tg.id, tg.isstandard, tg.name, tg.rawname, tg.flag,
tg.tagcollid, ti.ordering, ti.contextid AS taginstancecontextid, ti.itemid
FROM {tag_instance} ti
JOIN {tag} tg ON tg.id = ti.tagid
WHERE ti.itemtype = :itemtype AND ti.itemid $idsql ".
($component ? "AND ti.component = :component " : "").
($tiuserid ? "AND ti.tiuserid = :tiuserid " : "").
(($standardonly == self::STANDARD_ONLY) ? "AND tg.isstandard = 1 " : "").
(($standardonly == self::NOT_STANDARD_ONLY) ? "AND tg.isstandard = 0 " : "").
"ORDER BY ti.ordering ASC, ti.id";
$params['itemtype'] = $itemtype;
$params['component'] = $component;
$params['tiuserid'] = $tiuserid;
$records = $DB->get_records_sql($sql, $params);
$result = array();
foreach ($itemids as $itemid) {
$result[$itemid] = [];
}
foreach ($records as $id => $record) {
$result[$record->itemid][$id] = new static($record);
}
return $result;
}
/**
* Get the array of core_tag_tag objects associated with an item (instances).
*
* Use {@link core_tag_tag::get_item_tags_array()} if you wish to get the same data as simple array.
*
* @param string $component component responsible for tagging. For BC it can be empty but in this case the
* query will be slow because DB index will not be used.
* @param string $itemtype type of the tagged item
* @param int $itemid
* @param int $standardonly wether to return only standard tags or any
* @param int $tiuserid tag instance user id, only needed for tag areas with user tagging
* @return core_tag_tag[] each object contains additional fields taginstanceid, taginstancecontextid and ordering
*/
public static function get_item_tags($component, $itemtype, $itemid, $standardonly = self::BOTH_STANDARD_AND_NOT,
$tiuserid = 0) {
$tagobjects = static::get_items_tags($component, $itemtype, [$itemid], $standardonly, $tiuserid);
return empty($tagobjects) ? [] : $tagobjects[$itemid];
}
/**
* Returns the list of display names of the tags that are associated with an item
*
* This method is usually used to prefill the form data for the 'tags' form element
*
* @param string $component component responsible for tagging. For BC it can be empty but in this case the
* query will be slow because DB index will not be used.
* @param string $itemtype type of the tagged item
* @param int $itemid
* @param int $standardonly wether to return only standard tags or any
* @param int $tiuserid tag instance user id, only needed for tag areas with user tagging
* @param bool $ashtml (default true) if true will return htmlspecialchars encoded tag names
* @return string[] array of tags display names
*/
public static function get_item_tags_array($component, $itemtype, $itemid, $standardonly = self::BOTH_STANDARD_AND_NOT,
$tiuserid = 0, $ashtml = true) {
$tags = array();
foreach (static::get_item_tags($component, $itemtype, $itemid, $standardonly, $tiuserid) as $tag) {
$tags[$tag->id] = $tag->get_display_name($ashtml);
}
return $tags;
}
/**
* Sets the list of tag instances for one item (table record).
*
* Extra exsisting instances are removed, new ones are added. New tags are created if needed.
*
* This method can not be used for setting tags relations, please use set_related_tags()
*
* @param string $component component responsible for tagging
* @param string $itemtype type of the tagged item
* @param int $itemid
* @param context $context
* @param array $tagnames
* @param int $tiuserid tag instance user id, only needed for tag areas with user tagging (such as core/course)
*/
public static function set_item_tags($component, $itemtype, $itemid, context $context, $tagnames, $tiuserid = 0) {
if ($itemtype === 'tag') {
if ($tiuserid) {
throw new coding_exeption('Related tags can not have tag instance userid');
}
debugging('You can not use set_item_tags() for tagging a tag, please use set_related_tags()', DEBUG_DEVELOPER);
static::get($itemid, '*', MUST_EXIST)->set_related_tags($tagnames);
return;
}
if ($tagnames !== null && static::is_enabled($component, $itemtype) === false) {
// Tagging area is properly defined but not enabled - do nothing.
// Unless we are deleting the item tags ($tagnames === null), in which case proceed with deleting.
return;
}
// Apply clean_param() to all tags.
if ($tagnames) {
$tagcollid = core_tag_area::get_collection($component, $itemtype);
$tagobjects = static::create_if_missing($tagcollid, $tagnames);
} else {
$tagobjects = array();
}
$allowmultiplecontexts = core_tag_area::allows_tagging_in_multiple_contexts($component, $itemtype);
$currenttags = static::get_item_tags($component, $itemtype, $itemid, self::BOTH_STANDARD_AND_NOT, $tiuserid);
$taginstanceidstomovecontext = [];
// For data coherence reasons, it's better to remove deleted tags
// before adding new data: ordering could be duplicated.
foreach ($currenttags as $currenttag) {
$hasbeenrequested = array_key_exists($currenttag->name, $tagobjects);
$issamecontext = $currenttag->taginstancecontextid == $context->id;
if ($allowmultiplecontexts) {
// If the tag area allows multiple contexts then we should only be
// managing tags in the given $context. All other tags can be ignored.
$shoulddelete = $issamecontext && !$hasbeenrequested;
} else {
// If the tag area only allows tag instances in a single context then
// all tags that aren't in the requested tags should be deleted, regardless
// of their context, if they are not part of the new set of tags.
$shoulddelete = !$hasbeenrequested;
// If the tag instance isn't in the correct context (legacy data)
// then we should take this opportunity to update it with the correct
// context id.
if (!$shoulddelete && !$issamecontext) {
$currenttag->taginstancecontextid = $context->id;
$taginstanceidstomovecontext[] = $currenttag->taginstanceid;
}
}
if ($shoulddelete) {
$taginstance = (object)array('id' => $currenttag->taginstanceid,
'itemtype' => $itemtype, 'itemid' => $itemid,
'contextid' => $currenttag->taginstancecontextid, 'tiuserid' => $tiuserid);
$currenttag->delete_instance_as_record($taginstance, false);
}
}
if (!empty($taginstanceidstomovecontext)) {
static::change_instances_context($taginstanceidstomovecontext, $context);
}
$ordering = -1;
foreach ($tagobjects as $name => $tag) {
$ordering++;
foreach ($currenttags as $currenttag) {
$namesmatch = strval($currenttag->name) === strval($name);
if ($allowmultiplecontexts) {
// If the tag area allows multiple contexts then we should only
// skip adding a new instance if the existing one is in the correct
// context.
$contextsmatch = $currenttag->taginstancecontextid == $context->id;
$shouldskipinstance = $namesmatch && $contextsmatch;
} else {
// The existing behaviour for single context tag areas is to
// skip adding a new instance regardless of whether the existing
// instance is in the same context as the provided $context.
$shouldskipinstance = $namesmatch;
}
if ($shouldskipinstance) {
if ($currenttag->ordering != $ordering) {
$currenttag->update_instance_ordering($currenttag->taginstanceid, $ordering);
}
continue 2;
}
}
$tag->add_instance($component, $itemtype, $itemid, $context, $ordering, $tiuserid);
}
}
/**
* Removes all tags from an item.
*
* All tags will be removed even if tagging is disabled in this area. This is
* usually called when the item itself has been deleted.
*
* @param string $component component responsible for tagging
* @param string $itemtype type of the tagged item
* @param int $itemid
* @param int $tiuserid tag instance user id, only needed for tag areas with user tagging (such as core/course)
*/
public static function remove_all_item_tags($component, $itemtype, $itemid, $tiuserid = 0) {
$context = context_system::instance(); // Context will not be used.
static::set_item_tags($component, $itemtype, $itemid, $context, null, $tiuserid);
}
/**
* Adds a tag to an item, without overwriting the current tags.
*
* If the tag has already been added to the record, no changes are made.
*
* @param string $component the component that was tagged
* @param string $itemtype the type of record to tag ('post' for blogs, 'user' for users, etc.)
* @param int $itemid the id of the record to tag
* @param context $context the context of where this tag was assigned
* @param string $tagname the tag to add
* @param int $tiuserid tag instance user id, only needed for tag areas with user tagging (such as core/course)
* @return int id of tag_instance that was either created or already existed or null if tagging is not enabled
*/
public static function add_item_tag($component, $itemtype, $itemid, context $context, $tagname, $tiuserid = 0) {
global $DB;
if (static::is_enabled($component, $itemtype) === false) {
// Tagging area is properly defined but not enabled - do nothing.
return null;
}
$rawname = clean_param($tagname, PARAM_TAG);
$normalisedname = core_text::strtolower($rawname);
$tagcollid = core_tag_area::get_collection($component, $itemtype);
$usersql = $tiuserid ? " AND ti.tiuserid = :tiuserid " : "";
$sql = 'SELECT t.*, ti.id AS taginstanceid
FROM {tag} t
LEFT JOIN {tag_instance} ti ON ti.tagid = t.id AND ti.itemtype = :itemtype '.
$usersql .
'AND ti.itemid = :itemid AND ti.component = :component
WHERE t.name = :name AND t.tagcollid = :tagcollid';
$params = array('name' => $normalisedname, 'tagcollid' => $tagcollid, 'itemtype' => $itemtype,
'itemid' => $itemid, 'component' => $component, 'tiuserid' => $tiuserid);
$record = $DB->get_record_sql($sql, $params);
if ($record) {
if ($record->taginstanceid) {
// Tag was already added to the item, nothing to do here.
return $record->taginstanceid;
}
$tag = new static($record);
} else {
// The tag does not exist yet, create it.
$tags = static::add($tagcollid, array($tagname));
$tag = reset($tags);
}
$ordering = $DB->get_field_sql('SELECT MAX(ordering) FROM {tag_instance} ti
WHERE ti.itemtype = :itemtype AND ti.itemid = :itemid AND
ti.component = :component' . $usersql, $params);
return $tag->add_instance($component, $itemtype, $itemid, $context, $ordering + 1, $tiuserid);
}
/**
* Removes the tag from an item without changing the other tags
*
* @param string $component the component that was tagged
* @param string $itemtype the type of record to tag ('post' for blogs, 'user' for users, etc.)
* @param int $itemid the id of the record to tag
* @param string $tagname the tag to remove
* @param int $tiuserid tag instance user id, only needed for tag areas with user tagging (such as core/course)
*/
public static function remove_item_tag($component, $itemtype, $itemid, $tagname, $tiuserid = 0) {
global $DB;
if (static::is_enabled($component, $itemtype) === false) {
// Tagging area is properly defined but not enabled - do nothing.
return array();
}
$rawname = clean_param($tagname, PARAM_TAG);
$normalisedname = core_text::strtolower($rawname);
$usersql = $tiuserid ? " AND tiuserid = :tiuserid " : "";
$componentsql = $component ? " AND ti.component = :component " : "";
$sql = 'SELECT t.*, ti.id AS taginstanceid, ti.contextid AS taginstancecontextid, ti.ordering
FROM {tag} t JOIN {tag_instance} ti ON ti.tagid = t.id ' . $usersql . '
WHERE t.name = :name AND ti.itemtype = :itemtype
AND ti.itemid = :itemid ' . $componentsql;
$params = array('name' => $normalisedname,
'itemtype' => $itemtype, 'itemid' => $itemid, 'component' => $component,
'tiuserid' => $tiuserid);
if ($record = $DB->get_record_sql($sql, $params)) {
$taginstance = (object)array('id' => $record->taginstanceid,
'itemtype' => $itemtype, 'itemid' => $itemid,
'contextid' => $record->taginstancecontextid, 'tiuserid' => $tiuserid);
$tag = new static($record);
$tag->delete_instance_as_record($taginstance, false);
$componentsql = $component ? " AND component = :component " : "";
$sql = "UPDATE {tag_instance} SET ordering = ordering - 1
WHERE itemtype = :itemtype
AND itemid = :itemid $componentsql $usersql
AND ordering > :ordering";
$params['ordering'] = $record->ordering;
$DB->execute($sql, $params);
}
}
/**
* Allows to move all tag instances from one context to another
*
* @param string $component the component that was tagged
* @param string $itemtype the type of record to tag ('post' for blogs, 'user' for users, etc.)
* @param context $oldcontext
* @param context $newcontext
*/
public static function move_context($component, $itemtype, $oldcontext, $newcontext) {
global $DB;
if ($oldcontext instanceof context) {
$oldcontext = $oldcontext->id;
}
if ($newcontext instanceof context) {
$newcontext = $newcontext->id;
}
$DB->set_field('tag_instance', 'contextid', $newcontext,
array('component' => $component, 'itemtype' => $itemtype, 'contextid' => $oldcontext));
}
/**
* Moves all tags of the specified items to the new context
*
* @param string $component the component that was tagged
* @param string $itemtype the type of record to tag ('post' for blogs, 'user' for users, etc.)
* @param array $itemids
* @param context|int $newcontext target context to move tags to
*/
public static function change_items_context($component, $itemtype, $itemids, $newcontext) {
global $DB;
if (empty($itemids)) {
return;
}
if (!is_array($itemids)) {
$itemids = array($itemids);
}
list($sql, $params) = $DB->get_in_or_equal($itemids, SQL_PARAMS_NAMED);
$params['component'] = $component;
$params['itemtype'] = $itemtype;
if ($newcontext instanceof context) {
$newcontext = $newcontext->id;
}
$DB->set_field_select('tag_instance', 'contextid', $newcontext,
'component = :component AND itemtype = :itemtype AND itemid ' . $sql, $params);
}
/**
* Moves all of the specified tag instances into a new context.
*
* @param array $taginstanceids The list of tag instance ids that should be moved
* @param context $newcontext The context to move the tag instances into
*/
public static function change_instances_context(array $taginstanceids, context $newcontext) {
global $DB;
if (empty($taginstanceids)) {
return;
}
list($sql, $params) = $DB->get_in_or_equal($taginstanceids);
$DB->set_field_select('tag_instance', 'contextid', $newcontext->id, "id {$sql}", $params);
}
/**
* Updates the information about the tag
*
* @param array|stdClass $data data to update, may contain: isstandard, description, descriptionformat, rawname
* @return bool whether the tag was updated. False may be returned if: all new values match the existing,
* or it was attempted to rename the tag to the name that is already used.
*/
public function update($data) {
global $DB, $COURSE;
$allowedfields = array('isstandard', 'description', 'descriptionformat', 'rawname');
$data = (array)$data;
if ($extrafields = array_diff(array_keys($data), $allowedfields)) {
debugging('The field(s) '.join(', ', $extrafields).' will be ignored when updating the tag',
DEBUG_DEVELOPER);
}
$data = array_intersect_key($data, array_fill_keys($allowedfields, 1));
$this->ensure_fields_exist(array_merge(array('tagcollid', 'userid', 'name', 'rawname'), array_keys($data)), 'update');
// Validate the tag name.
if (array_key_exists('rawname', $data)) {
$data['rawname'] = clean_param($data['rawname'], PARAM_TAG);
$name = core_text::strtolower($data['rawname']);
if (!$name || $data['rawname'] === $this->rawname) {
unset($data['rawname']);
} else if ($existing = static::get_by_name($this->tagcollid, $name, 'id')) {
// Prevent the rename if a tag with that name already exists.
if ($existing->id != $this->id) {
throw new moodle_exception('namesalreadybeeingused', 'core_tag');
}
}
if (isset($data['rawname'])) {
$data['name'] = $name;
}
}
// Validate the tag type.
if (array_key_exists('isstandard', $data)) {
$data['isstandard'] = $data['isstandard'] ? 1 : 0;
}
// Find only the attributes that need to be changed.
$originalname = $this->name;
foreach ($data as $key => $value) {
if ($this->record->$key !== $value) {
$this->record->$key = $value;
} else {
unset($data[$key]);
}
}
if (empty($data)) {
return false;
}
$data['id'] = $this->id;
$data['timemodified'] = time();
$DB->update_record('tag', $data);
$event = \core\event\tag_updated::create(array(
'objectid' => $this->id,
'relateduserid' => $this->userid,
'context' => context_system::instance(),
'other' => array(
'name' => $this->name,
'rawname' => $this->rawname
)
));
if (isset($data['rawname'])) {
$event->set_legacy_logdata(array($COURSE->id, 'tag', 'update', 'index.php?id='. $this->id,
$originalname . '->'. $this->name));
}
$event->trigger();
return true;
}
/**
* Flag a tag as inappropriate
*/
public function flag() {
global $DB;
$this->ensure_fields_exist(array('name', 'userid', 'rawname', 'flag'), 'flag');
// Update all the tags to flagged.
$this->timemodified = time();
$this->flag++;
$DB->update_record('tag', array('timemodified' => $this->timemodified,
'flag' => $this->flag, 'id' => $this->id));
$event = \core\event\tag_flagged::create(array(
'objectid' => $this->id,
'relateduserid' => $this->userid,
'context' => context_system::instance(),
'other' => array(
'name' => $this->name,
'rawname' => $this->rawname
)
));
$event->trigger();
}
/**
* Remove the inappropriate flag on a tag.
*/
public function reset_flag() {
global $DB;
$this->ensure_fields_exist(array('name', 'userid', 'rawname', 'flag'), 'flag');
if (!$this->flag) {
// Nothing to do.
return false;
}
$this->timemodified = time();
$this->flag = 0;
$DB->update_record('tag', array('timemodified' => $this->timemodified,
'flag' => 0, 'id' => $this->id));
$event = \core\event\tag_unflagged::create(array(
'objectid' => $this->id,
'relateduserid' => $this->userid,
'context' => context_system::instance(),
'other' => array(
'name' => $this->name,
'rawname' => $this->rawname
)
));
$event->trigger();
}
/**
* Sets the list of tags related to this one.
*
* Tag relations are recorded by two instances linking two tags to each other.
* For tag relations ordering is not used and may be random.
*
* @param array $tagnames
*/
public function set_related_tags($tagnames) {
$context = context_system::instance();
$tagobjects = $tagnames ? static::create_if_missing($this->tagcollid, $tagnames) : array();
unset($tagobjects[$this->name]); // Never link to itself.
$currenttags = static::get_item_tags('core', 'tag', $this->id);
// For data coherence reasons, it's better to remove deleted tags
// before adding new data: ordering could be duplicated.
foreach ($currenttags as $currenttag) {
if (!array_key_exists($currenttag->name, $tagobjects)) {
$taginstance = (object)array('id' => $currenttag->taginstanceid,
'itemtype' => 'tag', 'itemid' => $this->id,
'contextid' => $context->id);
$currenttag->delete_instance_as_record($taginstance, false);
$this->delete_instance('core', 'tag', $currenttag->id);
}
}
foreach ($tagobjects as $name => $tag) {
foreach ($currenttags as $currenttag) {
if ($currenttag->name === $name) {
continue 2;
}
}
$this->add_instance('core', 'tag', $tag->id, $context, 0);
$tag->add_instance('core', 'tag', $this->id, $context, 0);
$currenttags[] = $tag;
}
}
/**
* Adds to the list of related tags without removing existing
*
* Tag relations are recorded by two instances linking two tags to each other.
* For tag relations ordering is not used and may be random.
*
* @param array $tagnames
*/
public function add_related_tags($tagnames) {
$context = context_system::instance();
$tagobjects = static::create_if_missing($this->tagcollid, $tagnames);
$currenttags = static::get_item_tags('core', 'tag', $this->id);
foreach ($tagobjects as $name => $tag) {
foreach ($currenttags as $currenttag) {
if ($currenttag->name === $name) {
continue 2;
}
}
$this->add_instance('core', 'tag', $tag->id, $context, 0);
$tag->add_instance('core', 'tag', $this->id, $context, 0);
$currenttags[] = $tag;
}
}
/**
* Returns the correlated tags of a tag, retrieved from the tag_correlation table.
*
* Correlated tags are calculated in cron based on existing tag instances.
*
* @param bool $keepduplicates if true, will return one record for each existing
* tag instance which may result in duplicates of the actual tags
* @return core_tag_tag[] an array of tag objects
*/
public function get_correlated_tags($keepduplicates = false) {
global $DB;
$correlated = $DB->get_field('tag_correlation', 'correlatedtags', array('tagid' => $this->id));
if (!$correlated) {
return array();
}
$correlated = preg_split('/\s*,\s*/', trim($correlated), -1, PREG_SPLIT_NO_EMPTY);
list($query, $params) = $DB->get_in_or_equal($correlated);
// This is (and has to) return the same fields as the query in core_tag_tag::get_item_tags().
$sql = "SELECT ti.id AS taginstanceid, tg.id, tg.isstandard, tg.name, tg.rawname, tg.flag,
tg.tagcollid, ti.ordering, ti.contextid AS taginstancecontextid, ti.itemid
FROM {tag} tg
INNER JOIN {tag_instance} ti ON tg.id = ti.tagid
WHERE tg.id $query AND tg.id <> ? AND tg.tagcollid = ?
ORDER BY ti.ordering ASC, ti.id";
$params[] = $this->id;
$params[] = $this->tagcollid;
$records = $DB->get_records_sql($sql, $params);
$seen = array();
$result = array();
foreach ($records as $id => $record) {
if (!$keepduplicates && !empty($seen[$record->id])) {
continue;
}
$result[$id] = new static($record);
$seen[$record->id] = true;
}
return $result;
}
/**
* Returns tags that this tag was manually set as related to
*
* @return core_tag_tag[]
*/
public function get_manual_related_tags() {
return self::get_item_tags('core', 'tag', $this->id);
}
/**
* 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 calculated
*
* @return core_tag_tag[] an array of tag objects
*/
public function get_related_tags() {
$manual = $this->get_manual_related_tags();
$automatic = $this->get_correlated_tags();
$relatedtags = array_merge($manual, $automatic);
// Remove duplicated tags (multiple instances of the same tag).
$seen = array();
foreach ($relatedtags as $instance => $tag) {
if (isset($seen[$tag->id])) {
unset($relatedtags[$instance]);
} else {
$seen[$tag->id] = 1;
}
}
return $relatedtags;
}
/**
* Find all items tagged with a tag of a given type ('post', 'user', etc.)
*
* @param string $component component responsible for tagging. For BC it can be empty but in this case the
* query will be slow because DB index will not be used.
* @param string $itemtype type to restrict search to
* @param int $limitfrom (optional, required if $limitnum is set) return a subset of records, starting at this point.
* @param int $limitnum (optional, required if $limitfrom is set) return a subset comprising this many records.
* @param string $subquery additional query to be appended to WHERE clause, refer to the itemtable as 'it'
* @param array $params additional parameters for the DB query
* @return array of matching objects, indexed by record id, from the table containing the type requested
*/
public function get_tagged_items($component, $itemtype, $limitfrom = '', $limitnum = '', $subquery = '', $params = array()) {
global $DB;
if (empty($itemtype) || !$DB->get_manager()->table_exists($itemtype)) {
return array();
}
$params = $params ? $params : array();
$query = "SELECT it.*
FROM {".$itemtype."} it INNER JOIN {tag_instance} tt ON it.id = tt.itemid
WHERE tt.itemtype = :itemtype AND tt.tagid = :tagid";
$params['itemtype'] = $itemtype;
$params['tagid'] = $this->id;
if ($component) {
$query .= ' AND tt.component = :component';
$params['component'] = $component;
}
if ($subquery) {
$query .= ' AND ' . $subquery;
}
$query .= ' ORDER BY it.id';
return $DB->get_records_sql($query, $params, $limitfrom, $limitnum);
}
/**
* Count how many items are tagged with a specific tag.
*
* @param string $component component responsible for tagging. For BC it can be empty but in this case the
* query will be slow because DB index will not be used.
* @param string $itemtype type to restrict search to
* @param string $subquery additional query to be appended to WHERE clause, refer to the itemtable as 'it'
* @param array $params additional parameters for the DB query
* @return int number of mathing tags.
*/
public function count_tagged_items($component, $itemtype, $subquery = '', $params = array()) {
global $DB;
if (empty($itemtype) || !$DB->get_manager()->table_exists($itemtype)) {
return 0;
}
$params = $params ? $params : array();
$query = "SELECT COUNT(it.id)
FROM {".$itemtype."} it INNER JOIN {tag_instance} tt ON it.id = tt.itemid
WHERE tt.itemtype = :itemtype AND tt.tagid = :tagid";
$params['itemtype'] = $itemtype;
$params['tagid'] = $this->id;
if ($component) {
$query .= ' AND tt.component = :component';
$params['component'] = $component;
}
if ($subquery) {
$query .= ' AND ' . $subquery;
}
return $DB->get_field_sql($query, $params);
}
/**
* Determine if an item is tagged with a specific tag
*
* Note that this is a static method and not a method of core_tag object because the tag might not exist yet,
* for example user searches for "php" and we offer him to add "php" to his interests.
*
* @param string $component component responsible for tagging. For BC it can be empty but in this case the
* query will be slow because DB index will not be used.
* @param string $itemtype the record type to look for
* @param int $itemid the record id to look for
* @param string $tagname a tag name
* @return int 1 if it is tagged, 0 otherwise
*/
public static function is_item_tagged_with($component, $itemtype, $itemid, $tagname) {
global $DB;
$tagcollid = core_tag_area::get_collection($component, $itemtype);
$query = 'SELECT 1 FROM {tag} t
JOIN {tag_instance} ti ON ti.tagid = t.id
WHERE t.name = ? AND t.tagcollid = ? AND ti.itemtype = ? AND ti.itemid = ?';
$cleanname = core_text::strtolower(clean_param($tagname, PARAM_TAG));
$params = array($cleanname, $tagcollid, $itemtype, $itemid);
if ($component) {
$query .= ' AND ti.component = ?';
$params[] = $component;
}
return $DB->record_exists_sql($query, $params) ? 1 : 0;
}
/**
* Returns whether the tag area is enabled
*
* @param string $component component responsible for tagging
* @param string $itemtype what is being tagged, for example, 'post', 'course', 'user', etc.
* @return bool|null
*/
public static function is_enabled($component, $itemtype) {
return core_tag_area::is_enabled($component, $itemtype);
}
/**
* Retrieves contents of tag area for the tag/index.php page
*
* @param stdClass $tagarea
* @param bool $exclusivemode if set to true it means that no other entities tagged with this tag
* are displayed on the page and the per-page limit may be bigger
* @param int $fromctx context id where the link was displayed, may be used by callbacks
* to display items in the same context first
* @param int $ctx context id where to search for records
* @param bool $rec search in subcontexts as well
* @param int $page 0-based number of page being displayed
* @return \core_tag\output\tagindex
*/
public function get_tag_index($tagarea, $exclusivemode, $fromctx, $ctx, $rec, $page = 0) {
global $CFG;
if (!empty($tagarea->callback)) {
if (!empty($tagarea->callbackfile)) {
require_once($CFG->dirroot . '/' . ltrim($tagarea->callbackfile, '/'));
}
$callback = $tagarea->callback;
return call_user_func_array($callback, [$this, $exclusivemode, $fromctx, $ctx, $rec, $page]);
}
return null;
}
/**
* Returns formatted description of the tag
*
* @param array $options
* @return string
*/
public function get_formatted_description($options = array()) {
$options = empty($options) ? array() : (array)$options;
$options += array('para' => false, 'overflowdiv' => true);
$description = file_rewrite_pluginfile_urls($this->description, 'pluginfile.php',
context_system::instance()->id, 'tag', 'description', $this->id);
return format_text($description, $this->descriptionformat, $options);
}
/**
* Returns the list of tag links available for the current user (edit, flag, etc.)
*
* @return array
*/
public function get_links() {
global $USER;
$links = array();
if (!isloggedin() || isguestuser()) {
return $links;
}
$tagname = $this->get_display_name();
$systemcontext = context_system::instance();
// Add a link for users to add/remove this from their interests.
if (static::is_enabled('core', 'user') && core_tag_area::get_collection('core', 'user') == $this->tagcollid) {
if (static::is_item_tagged_with('core', 'user', $USER->id, $this->name)) {
$url = new moodle_url('/tag/user.php', array('action' => 'removeinterest',
'sesskey' => sesskey(), 'tag' => $this->rawname));
$links[] = html_writer::link($url, get_string('removetagfrommyinterests', 'tag', $tagname),
array('class' => 'removefrommyinterests'));
} else {
$url = new moodle_url('/tag/user.php', array('action' => 'addinterest',
'sesskey' => sesskey(), 'tag' => $this->rawname));
$links[] = html_writer::link($url, get_string('addtagtomyinterests', 'tag', $tagname),
array('class' => 'addtomyinterests'));
}
}
// Flag as inappropriate link. Only people with moodle/tag:flag capability.
if (has_capability('moodle/tag:flag', $systemcontext)) {
$url = new moodle_url('/tag/user.php', array('action' => 'flaginappropriate',
'sesskey' => sesskey(), 'id' => $this->id));
$links[] = html_writer::link($url, get_string('flagasinappropriate', 'tag', $tagname),
array('class' => 'flagasinappropriate'));
}
// Edit tag: Only people with moodle/tag:edit capability who either have it as an interest or can manage tags.
if (has_capability('moodle/tag:edit', $systemcontext) ||
has_capability('moodle/tag:manage', $systemcontext)) {
$url = new moodle_url('/tag/edit.php', array('id' => $this->id));
$links[] = html_writer::link($url, get_string('edittag', 'tag'),
array('class' => 'edittag'));
}
return $links;
}
/**
* Delete one or more tag, and all their instances if there are any left.
*
* @param int|array $tagids one tagid (int), or one array of tagids to delete
* @return bool true on success, false otherwise
*/
public static function delete_tags($tagids) {
global $DB;
if (!is_array($tagids)) {
$tagids = array($tagids);
}
if (empty($tagids)) {
return;
}
// Use the tagids to create a select statement to be used later.
list($tagsql, $tagparams) = $DB->get_in_or_equal($tagids);
// Store the tags and tag instances we are going to delete.
$tags = $DB->get_records_select('tag', 'id ' . $tagsql, $tagparams);
$taginstances = $DB->get_records_select('tag_instance', 'tagid ' . $tagsql, $tagparams);
// Delete all the tag instances.
$select = 'WHERE tagid ' . $tagsql;
$sql = "DELETE FROM {tag_instance} $select";
$DB->execute($sql, $tagparams);
// Delete all the tag correlations.
$sql = "DELETE FROM {tag_correlation} $select";
$DB->execute($sql, $tagparams);
// Delete all the tags.
$select = 'WHERE id ' . $tagsql;
$sql = "DELETE FROM {tag} $select";
$DB->execute($sql, $tagparams);
// Fire an event that these items were untagged.
if ($taginstances) {
// Save the system context in case the 'contextid' column in the 'tag_instance' table is null.
$syscontextid = context_system::instance()->id;
// Loop through the tag instances and fire a 'tag_removed'' event.
foreach ($taginstances as $taginstance) {
// We can not fire an event with 'null' as the contextid.
if (is_null($taginstance->contextid)) {
$taginstance->contextid = $syscontextid;
}
// Trigger tag removed event.
\core\event\tag_removed::create_from_tag_instance($taginstance,
$tags[$taginstance->tagid]->name, $tags[$taginstance->tagid]->rawname,
true)->trigger();
}
}
// Fire an event that these tags were deleted.
if ($tags) {
$context = context_system::instance();
foreach ($tags as $tag) {
// Delete all files associated with this tag.
$fs = get_file_storage();
$files = $fs->get_area_files($context->id, 'tag', 'description', $tag->id);
foreach ($files as $file) {
$file->delete();
}
// Trigger an event for deleting this tag.
$event = \core\event\tag_deleted::create(array(
'objectid' => $tag->id,
'relateduserid' => $tag->userid,
'context' => $context,
'other' => array(
'name' => $tag->name,
'rawname' => $tag->rawname
)
));
$event->add_record_snapshot('tag', $tag);
$event->trigger();
}
}
return true;
}
/**
* Combine together correlated tags of several tags
*
* This is a help method for method combine_tags()
*
* @param core_tag_tag[] $tags
*/
protected function combine_correlated_tags($tags) {
global $DB;
$ids = array_map(function($t) {
return $t->id;
}, $tags);
// Retrieve the correlated tags of this tag and correlated tags of all tags to be merged in one query
// but store them separately. Calculate the list of correlated tags that need to be added to the current.
list($sql, $params) = $DB->get_in_or_equal($ids);
$params[] = $this->id;
$records = $DB->get_records_select('tag_correlation', 'tagid '.$sql.' OR tagid = ?',
$params, '', 'tagid, id, correlatedtags');
$correlated = array();
$mycorrelated = array();
foreach ($records as $record) {
$taglist = preg_split('/\s*,\s*/', trim($record->correlatedtags), -1, PREG_SPLIT_NO_EMPTY);
if ($record->tagid == $this->id) {
$mycorrelated = $taglist;
} else {
$correlated = array_merge($correlated, $taglist);
}
}
array_unique($correlated);
// Strip out from $correlated the ids of the tags that are already in $mycorrelated
// or are one of the tags that are going to be combined.
$correlated = array_diff($correlated, [$this->id], $ids, $mycorrelated);
if (empty($correlated)) {
// Nothing to do, ignore situation when current tag is correlated to one of the merged tags - they will
// be deleted later and get_tag_correlation() will not return them. Next cron will clean everything up.
return;
}
// Update correlated tags of this tag.
$newcorrelatedlist = join(',', array_merge($mycorrelated, $correlated));
if (isset($records[$this->id])) {
$DB->update_record('tag_correlation', array('id' => $records[$this->id]->id, 'correlatedtags' => $newcorrelatedlist));
} else {
$DB->insert_record('tag_correlation', array('tagid' => $this->id, 'correlatedtags' => $newcorrelatedlist));
}
// Add this tag to the list of correlated tags of each tag in $correlated.
list($sql, $params) = $DB->get_in_or_equal($correlated);
$records = $DB->get_records_select('tag_correlation', 'tagid '.$sql, $params, '', 'tagid, id, correlatedtags');
foreach ($correlated as $tagid) {
if (isset($records[$tagid])) {
$newcorrelatedlist = $records[$tagid]->correlatedtags . ',' . $this->id;
$DB->update_record('tag_correlation', array('id' => $records[$tagid]->id, 'correlatedtags' => $newcorrelatedlist));
} else {
$DB->insert_record('tag_correlation', array('tagid' => $tagid, 'correlatedtags' => '' . $this->id));
}
}
}
/**
* Combines several other tags into this one
*
* Combining rules:
* - current tag becomes the "main" one, all instances
* pointing to other tags are changed to point to it.
* - if any of the tags is standard, the "main" tag becomes standard too
* - all tags except for the current ("main") are deleted, even when they are standard
*
* @param core_tag_tag[] $tags tags to combine into this one
*/
public function combine_tags($tags) {
global $DB;
$this->ensure_fields_exist(array('id', 'tagcollid', 'isstandard', 'name', 'rawname'), 'combine_tags');
// Retrieve all tag objects, find if there are any standard tags in the set.
$isstandard = false;
$tagstocombine = array();
$ids = array();
$relatedtags = $this->get_manual_related_tags();
foreach ($tags as $tag) {
$tag->ensure_fields_exist(array('id', 'tagcollid', 'isstandard', 'tagcollid', 'name', 'rawname'), 'combine_tags');
if ($tag && $tag->id != $this->id && $tag->tagcollid == $this->tagcollid) {
$isstandard = $isstandard || $tag->isstandard;
$tagstocombine[$tag->name] = $tag;
$ids[] = $tag->id;
$relatedtags = array_merge($relatedtags, $tag->get_manual_related_tags());
}
}
if (empty($tagstocombine)) {
// Nothing to do.
return;
}
// Combine all manually set related tags, exclude itself all the tags it is about to be combined with.
if ($relatedtags) {
$relatedtags = array_map(function($t) {
return $t->name;
}, $relatedtags);
array_unique($relatedtags);
$relatedtags = array_diff($relatedtags, [$this->name], array_keys($tagstocombine));
}
$this->set_related_tags($relatedtags);
// Combine all correlated tags, exclude itself all the tags it is about to be combined with.
$this->combine_correlated_tags($tagstocombine);
// If any of the duplicate tags are standard, mark this one as standard too.
if ($isstandard && !$this->isstandard) {
$this->update(array('isstandard' => 1));
}
// Go through all instances of each tag that needs to be combined and make them point to this tag instead.
// We go though the list one by one because otherwise looking-for-duplicates logic would be too complicated.
foreach ($tagstocombine as $tag) {
$params = array('tagid' => $tag->id, 'mainid' => $this->id);
$mainsql = 'SELECT ti.*, t.name, t.rawname, tim.id AS alreadyhasmaintag '
. 'FROM {tag_instance} ti '
. 'LEFT JOIN {tag} t ON t.id = ti.tagid '
. 'LEFT JOIN {tag_instance} tim ON ti.component = tim.component AND '
. ' ti.itemtype = tim.itemtype AND ti.itemid = tim.itemid AND '
. ' ti.tiuserid = tim.tiuserid AND tim.tagid = :mainid '
. 'WHERE ti.tagid = :tagid';
$records = $DB->get_records_sql($mainsql, $params);
foreach ($records as $record) {
if ($record->alreadyhasmaintag) {
// Item is tagged with both main tag and the duplicate tag.
// Remove instance pointing to the duplicate tag.
$tag->delete_instance_as_record($record, false);
$sql = "UPDATE {tag_instance} SET ordering = ordering - 1
WHERE itemtype = :itemtype
AND itemid = :itemid AND component = :component AND tiuserid = :tiuserid
AND ordering > :ordering";
$DB->execute($sql, (array)$record);
} else {
// Item is tagged only with duplicate tag but not the main tag.
// Replace tagid in the instance pointing to the duplicate tag with this tag.
$DB->update_record('tag_instance', array('id' => $record->id, 'tagid' => $this->id));
\core\event\tag_removed::create_from_tag_instance($record, $record->name, $record->rawname)->trigger();
$record->tagid = $this->id;
\core\event\tag_added::create_from_tag_instance($record, $this->name, $this->rawname)->trigger();
}
}
}
// Finally delete all tags that we combined into the current one.
self::delete_tags($ids);
}
/**
* Retrieve a list of tags that have been used to tag the given $component
* and $itemtype in the provided $contexts.
*
* @param string $component The tag instance component
* @param string $itemtype The tag instance item type
* @param context[] $contexts The list of contexts to look for tag instances in
* @return core_tag_tag[]
*/
public static function get_tags_by_area_in_contexts($component, $itemtype, array $contexts) {
global $DB;
$params = [$component, $itemtype];
$contextids = array_map(function($context) {
return $context->id;
}, $contexts);
list($contextsql, $contextsqlparams) = $DB->get_in_or_equal($contextids);
$params = array_merge($params, $contextsqlparams);
$subsql = "SELECT DISTINCT t.id
FROM {tag} t
JOIN {tag_instance} ti ON t.id = ti.tagid
WHERE component = ?
AND itemtype = ?
AND contextid {$contextsql}";
$sql = "SELECT tt.*
FROM ($subsql) tv
JOIN {tag} tt ON tt.id = tv.id";
return array_map(function($record) {
return new core_tag_tag($record);
}, $DB->get_records_sql($sql, $params));
}
}