MDL-49489 caching: Prevent full coursecontact purge
[moodle.git] / lib / coursecatlib.php
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1<?php
2// This file is part of Moodle - http://moodle.org/
3//
4// Moodle is free software: you can redistribute it and/or modify
5// it under the terms of the GNU General Public License as published by
6// the Free Software Foundation, either version 3 of the License, or
7// (at your option) any later version.
8//
9// Moodle is distributed in the hope that it will be useful,
10// but WITHOUT ANY WARRANTY; without even the implied warranty of
11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12// GNU General Public License for more details.
13//
14// You should have received a copy of the GNU General Public License
15// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
16
17/**
18 * Contains class coursecat reponsible for course category operations
19 *
20 * @package core
21 * @subpackage course
22 * @copyright 2013 Marina Glancy
23 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
24 */
25
26defined('MOODLE_INTERNAL') || die();
27
28/**
29 * Class to store, cache, render and manage course category
30 *
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31 * @property-read int $id
32 * @property-read string $name
33 * @property-read string $idnumber
34 * @property-read string $description
35 * @property-read int $descriptionformat
36 * @property-read int $parent
37 * @property-read int $sortorder
38 * @property-read int $coursecount
39 * @property-read int $visible
40 * @property-read int $visibleold
41 * @property-read int $timemodified
42 * @property-read int $depth
43 * @property-read string $path
44 * @property-read string $theme
45 *
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46 * @package core
47 * @subpackage course
48 * @copyright 2013 Marina Glancy
49 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
50 */
51class coursecat implements renderable, cacheable_object, IteratorAggregate {
52 /** @var coursecat stores pseudo category with id=0. Use coursecat::get(0) to retrieve */
53 protected static $coursecat0;
54
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55 /** Do not fetch course contacts more often than once per hour. */
56 const CACHE_COURSE_CONTACTS_TTL = 3600;
36ba8fde 57
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58 /** @var array list of all fields and their short name and default value for caching */
59 protected static $coursecatfields = array(
60 'id' => array('id', 0),
61 'name' => array('na', ''),
62 'idnumber' => array('in', null),
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63 'description' => null, // Not cached.
64 'descriptionformat' => null, // Not cached.
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65 'parent' => array('pa', 0),
66 'sortorder' => array('so', 0),
e4008e9d 67 'coursecount' => array('cc', 0),
b33389d2 68 'visible' => array('vi', 1),
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69 'visibleold' => null, // Not cached.
70 'timemodified' => null, // Not cached.
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71 'depth' => array('dh', 1),
72 'path' => array('ph', null),
5dc361e1 73 'theme' => null, // Not cached.
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74 );
75
76 /** @var int */
77 protected $id;
78
79 /** @var string */
80 protected $name = '';
81
82 /** @var string */
83 protected $idnumber = null;
84
85 /** @var string */
15d50fff 86 protected $description = false;
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87
88 /** @var int */
15d50fff 89 protected $descriptionformat = false;
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90
91 /** @var int */
92 protected $parent = 0;
93
94 /** @var int */
95 protected $sortorder = 0;
96
97 /** @var int */
15d50fff 98 protected $coursecount = false;
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99
100 /** @var int */
101 protected $visible = 1;
102
103 /** @var int */
15d50fff 104 protected $visibleold = false;
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105
106 /** @var int */
15d50fff 107 protected $timemodified = false;
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108
109 /** @var int */
110 protected $depth = 0;
111
112 /** @var string */
113 protected $path = '';
114
115 /** @var string */
15d50fff 116 protected $theme = false;
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117
118 /** @var bool */
119 protected $fromcache;
120
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121 /** @var bool */
122 protected $hasmanagecapability = null;
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123
124 /**
125 * Magic setter method, we do not want anybody to modify properties from the outside
9c6cfc08 126 *
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127 * @param string $name
128 * @param mixed $value
129 */
130 public function __set($name, $value) {
131 debugging('Can not change coursecat instance properties!', DEBUG_DEVELOPER);
132 }
133
134 /**
15d50fff 135 * Magic method getter, redirects to read only values. Queries from DB the fields that were not cached
9c6cfc08 136 *
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137 * @param string $name
138 * @return mixed
139 */
140 public function __get($name) {
15d50fff 141 global $DB;
b33389d2 142 if (array_key_exists($name, self::$coursecatfields)) {
15d50fff 143 if ($this->$name === false) {
5dc361e1 144 // Property was not retrieved from DB, retrieve all not retrieved fields.
0a02b80c 145 $notretrievedfields = array_diff_key(self::$coursecatfields, array_filter(self::$coursecatfields));
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146 $record = $DB->get_record('course_categories', array('id' => $this->id),
147 join(',', array_keys($notretrievedfields)), MUST_EXIST);
148 foreach ($record as $key => $value) {
149 $this->$key = $value;
150 }
151 }
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152 return $this->$name;
153 }
154 debugging('Invalid coursecat property accessed! '.$name, DEBUG_DEVELOPER);
155 return null;
156 }
157
158 /**
159 * Full support for isset on our magic read only properties.
9c6cfc08 160 *
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161 * @param string $name
162 * @return bool
163 */
164 public function __isset($name) {
165 if (array_key_exists($name, self::$coursecatfields)) {
166 return isset($this->$name);
167 }
168 return false;
169 }
170
171 /**
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172 * All properties are read only, sorry.
173 *
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174 * @param string $name
175 */
176 public function __unset($name) {
177 debugging('Can not unset coursecat instance properties!', DEBUG_DEVELOPER);
178 }
179
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180 /**
181 * Create an iterator because magic vars can't be seen by 'foreach'.
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182 *
183 * implementing method from interface IteratorAggregate
184 *
185 * @return ArrayIterator
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186 */
187 public function getIterator() {
188 $ret = array();
189 foreach (self::$coursecatfields as $property => $unused) {
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190 if ($this->$property !== false) {
191 $ret[$property] = $this->$property;
192 }
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193 }
194 return new ArrayIterator($ret);
195 }
196
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197 /**
198 * Constructor
199 *
200 * Constructor is protected, use coursecat::get($id) to retrieve category
201 *
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202 * @param stdClass $record record from DB (may not contain all fields)
203 * @param bool $fromcache whether it is being restored from cache
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204 */
205 protected function __construct(stdClass $record, $fromcache = false) {
9c6cfc08 206 context_helper::preload_from_record($record);
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207 foreach ($record as $key => $val) {
208 if (array_key_exists($key, self::$coursecatfields)) {
209 $this->$key = $val;
210 }
211 }
212 $this->fromcache = $fromcache;
213 }
214
215 /**
216 * Returns coursecat object for requested category
217 *
218 * If category is not visible to user it is treated as non existing
15d50fff 219 * unless $alwaysreturnhidden is set to true
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220 *
221 * If id is 0, the pseudo object for root category is returned (convenient
222 * for calling other functions such as get_children())
223 *
224 * @param int $id category id
225 * @param int $strictness whether to throw an exception (MUST_EXIST) or
226 * return null (IGNORE_MISSING) in case the category is not found or
227 * not visible to current user
15d50fff 228 * @param bool $alwaysreturnhidden set to true if you want an object to be
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229 * returned even if this category is not visible to the current user
230 * (category is hidden and user does not have
231 * 'moodle/category:viewhiddencategories' capability). Use with care!
15d50fff 232 * @return null|coursecat
5dc361e1 233 * @throws moodle_exception
b33389d2 234 */
15d50fff 235 public static function get($id, $strictness = MUST_EXIST, $alwaysreturnhidden = false) {
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236 if (!$id) {
237 if (!isset(self::$coursecat0)) {
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238 $record = new stdClass();
239 $record->id = 0;
240 $record->visible = 1;
241 $record->depth = 0;
242 $record->path = '';
243 self::$coursecat0 = new coursecat($record);
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244 }
245 return self::$coursecat0;
246 }
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247 $coursecatrecordcache = cache::make('core', 'coursecatrecords');
248 $coursecat = $coursecatrecordcache->get($id);
15d50fff 249 if ($coursecat === false) {
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250 if ($records = self::get_records('cc.id = :id', array('id' => $id))) {
251 $record = reset($records);
252 $coursecat = new coursecat($record);
5dc361e1 253 // Store in cache.
eabbfa82 254 $coursecatrecordcache->set($id, $coursecat);
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255 }
256 }
15d50fff 257 if ($coursecat && ($alwaysreturnhidden || $coursecat->is_uservisible())) {
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258 return $coursecat;
259 } else {
260 if ($strictness == MUST_EXIST) {
9a4231e9 261 throw new moodle_exception('unknowncategory');
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262 }
263 }
264 return null;
265 }
266
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267 /**
268 * Load many coursecat objects.
269 *
270 * @global moodle_database $DB
271 * @param array $ids An array of category ID's to load.
484c4c6c 272 * @return coursecat[]
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273 */
274 public static function get_many(array $ids) {
275 global $DB;
276 $coursecatrecordcache = cache::make('core', 'coursecatrecords');
277 $categories = $coursecatrecordcache->get_many($ids);
278 $toload = array();
279 foreach ($categories as $id => $result) {
280 if ($result === false) {
281 $toload[] = $id;
282 }
283 }
284 if (!empty($toload)) {
285 list($where, $params) = $DB->get_in_or_equal($toload, SQL_PARAMS_NAMED);
286 $records = self::get_records('cc.id '.$where, $params);
287 $toset = array();
288 foreach ($records as $record) {
289 $categories[$record->id] = new coursecat($record);
290 $toset[$record->id] = $categories[$record->id];
291 }
292 $coursecatrecordcache->set_many($toset);
293 }
294 return $categories;
295 }
296
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297 /**
298 * Returns the first found category
299 *
300 * Note that if there are no categories visible to the current user on the first level,
301 * the invisible category may be returned
302 *
303 * @return coursecat
304 */
305 public static function get_default() {
306 if ($visiblechildren = self::get(0)->get_children()) {
307 $defcategory = reset($visiblechildren);
308 } else {
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309 $toplevelcategories = self::get_tree(0);
310 $defcategoryid = $toplevelcategories[0];
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311 $defcategory = self::get($defcategoryid, MUST_EXIST, true);
312 }
313 return $defcategory;
314 }
315
316 /**
317 * Restores the object after it has been externally modified in DB for example
318 * during {@link fix_course_sortorder()}
319 */
320 protected function restore() {
5dc361e1 321 // Update all fields in the current object.
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322 $newrecord = self::get($this->id, MUST_EXIST, true);
323 foreach (self::$coursecatfields as $key => $unused) {
324 $this->$key = $newrecord->$key;
325 }
326 }
327
328 /**
329 * Creates a new category either from form data or from raw data
330 *
331 * Please note that this function does not verify access control.
332 *
333 * Exception is thrown if name is missing or idnumber is duplicating another one in the system.
334 *
335 * Category visibility is inherited from parent unless $data->visible = 0 is specified
336 *
337 * @param array|stdClass $data
338 * @param array $editoroptions if specified, the data is considered to be
339 * form data and file_postupdate_standard_editor() is being called to
340 * process images in description.
341 * @return coursecat
342 * @throws moodle_exception
343 */
344 public static function create($data, $editoroptions = null) {
345 global $DB, $CFG;
346 $data = (object)$data;
347 $newcategory = new stdClass();
348
349 $newcategory->descriptionformat = FORMAT_MOODLE;
350 $newcategory->description = '';
5dc361e1 351 // Copy all description* fields regardless of whether this is form data or direct field update.
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352 foreach ($data as $key => $value) {
353 if (preg_match("/^description/", $key)) {
354 $newcategory->$key = $value;
355 }
356 }
357
358 if (empty($data->name)) {
359 throw new moodle_exception('categorynamerequired');
360 }
2f1e464a 361 if (core_text::strlen($data->name) > 255) {
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362 throw new moodle_exception('categorytoolong');
363 }
364 $newcategory->name = $data->name;
365
5dc361e1 366 // Validate and set idnumber.
b33389d2 367 if (!empty($data->idnumber)) {
2f1e464a 368 if (core_text::strlen($data->idnumber) > 100) {
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369 throw new moodle_exception('idnumbertoolong');
370 }
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371 if ($DB->record_exists('course_categories', array('idnumber' => $data->idnumber))) {
372 throw new moodle_exception('categoryidnumbertaken');
373 }
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374 }
375 if (isset($data->idnumber)) {
376 $newcategory->idnumber = $data->idnumber;
377 }
378
379 if (isset($data->theme) && !empty($CFG->allowcategorythemes)) {
380 $newcategory->theme = $data->theme;
381 }
382
383 if (empty($data->parent)) {
384 $parent = self::get(0);
385 } else {
386 $parent = self::get($data->parent, MUST_EXIST, true);
387 }
388 $newcategory->parent = $parent->id;
389 $newcategory->depth = $parent->depth + 1;
390
5dc361e1 391 // By default category is visible, unless visible = 0 is specified or parent category is hidden.
b33389d2 392 if (isset($data->visible) && !$data->visible) {
5dc361e1 393 // Create a hidden category.
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394 $newcategory->visible = $newcategory->visibleold = 0;
395 } else {
5dc361e1 396 // Create a category that inherits visibility from parent.
b33389d2 397 $newcategory->visible = $parent->visible;
5dc361e1 398 // In case parent is hidden, when it changes visibility this new subcategory will automatically become visible too.
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399 $newcategory->visibleold = 1;
400 }
401
402 $newcategory->sortorder = 0;
403 $newcategory->timemodified = time();
404
405 $newcategory->id = $DB->insert_record('course_categories', $newcategory);
406
5dc361e1 407 // Update path (only possible after we know the category id.
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408 $path = $parent->path . '/' . $newcategory->id;
409 $DB->set_field('course_categories', 'path', $path, array('id' => $newcategory->id));
410
5dc361e1 411 // We should mark the context as dirty.
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412 context_coursecat::instance($newcategory->id)->mark_dirty();
413
414 fix_course_sortorder();
415
5dc361e1 416 // If this is data from form results, save embedded files and update description.
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417 $categorycontext = context_coursecat::instance($newcategory->id);
418 if ($editoroptions) {
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419 $newcategory = file_postupdate_standard_editor($newcategory, 'description', $editoroptions, $categorycontext,
420 'coursecat', 'description', 0);
b33389d2 421
5dc361e1 422 // Update only fields description and descriptionformat.
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423 $updatedata = new stdClass();
424 $updatedata->id = $newcategory->id;
425 $updatedata->description = $newcategory->description;
426 $updatedata->descriptionformat = $newcategory->descriptionformat;
b33389d2 427 $DB->update_record('course_categories', $updatedata);
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428 }
429
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430 $event = \core\event\course_category_created::create(array(
431 'objectid' => $newcategory->id,
432 'context' => $categorycontext
433 ));
434 $event->trigger();
435
eabbfa82 436 cache_helper::purge_by_event('changesincoursecat');
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437
438 return self::get($newcategory->id, MUST_EXIST, true);
439 }
440
441 /**
442 * Updates the record with either form data or raw data
443 *
444 * Please note that this function does not verify access control.
445 *
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446 * This function calls coursecat::change_parent_raw if field 'parent' is updated.
447 * It also calls coursecat::hide_raw or coursecat::show_raw if 'visible' is updated.
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448 * Visibility is changed first and then parent is changed. This means that
449 * if parent category is hidden, the current category will become hidden
450 * too and it may overwrite whatever was set in field 'visible'.
451 *
452 * Note that fields 'path' and 'depth' can not be updated manually
453 * Also coursecat::update() can not directly update the field 'sortoder'
454 *
455 * @param array|stdClass $data
456 * @param array $editoroptions if specified, the data is considered to be
457 * form data and file_postupdate_standard_editor() is being called to
458 * process images in description.
459 * @throws moodle_exception
460 */
461 public function update($data, $editoroptions = null) {
462 global $DB, $CFG;
463 if (!$this->id) {
5dc361e1 464 // There is no actual DB record associated with root category.
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465 return;
466 }
467
468 $data = (object)$data;
469 $newcategory = new stdClass();
470 $newcategory->id = $this->id;
471
5dc361e1 472 // Copy all description* fields regardless of whether this is form data or direct field update.
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473 foreach ($data as $key => $value) {
474 if (preg_match("/^description/", $key)) {
475 $newcategory->$key = $value;
476 }
477 }
478
479 if (isset($data->name) && empty($data->name)) {
480 throw new moodle_exception('categorynamerequired');
481 }
482
483 if (!empty($data->name) && $data->name !== $this->name) {
2f1e464a 484 if (core_text::strlen($data->name) > 255) {
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485 throw new moodle_exception('categorytoolong');
486 }
487 $newcategory->name = $data->name;
488 }
489
490 if (isset($data->idnumber) && $data->idnumber != $this->idnumber) {
2f1e464a 491 if (core_text::strlen($data->idnumber) > 100) {
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492 throw new moodle_exception('idnumbertoolong');
493 }
9c6cfc08 494 if ($DB->record_exists('course_categories', array('idnumber' => $data->idnumber))) {
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495 throw new moodle_exception('categoryidnumbertaken');
496 }
497 $newcategory->idnumber = $data->idnumber;
498 }
499
500 if (isset($data->theme) && !empty($CFG->allowcategorythemes)) {
501 $newcategory->theme = $data->theme;
502 }
503
504 $changes = false;
505 if (isset($data->visible)) {
506 if ($data->visible) {
15d50fff 507 $changes = $this->show_raw();
b33389d2 508 } else {
15d50fff 509 $changes = $this->hide_raw(0);
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510 }
511 }
512
513 if (isset($data->parent) && $data->parent != $this->parent) {
514 if ($changes) {
eabbfa82 515 cache_helper::purge_by_event('changesincoursecat');
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516 }
517 $parentcat = self::get($data->parent, MUST_EXIST, true);
15d50fff 518 $this->change_parent_raw($parentcat);
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519 fix_course_sortorder();
520 }
521
522 $newcategory->timemodified = time();
523
c4cea8cb 524 $categorycontext = $this->get_context();
b33389d2 525 if ($editoroptions) {
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526 $newcategory = file_postupdate_standard_editor($newcategory, 'description', $editoroptions, $categorycontext,
527 'coursecat', 'description', 0);
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528 }
529 $DB->update_record('course_categories', $newcategory);
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530
531 $event = \core\event\course_category_updated::create(array(
532 'objectid' => $newcategory->id,
533 'context' => $categorycontext
534 ));
535 $event->trigger();
536
b33389d2 537 fix_course_sortorder();
5dc361e1 538 // Purge cache even if fix_course_sortorder() did not do it.
eabbfa82 539 cache_helper::purge_by_event('changesincoursecat');
b33389d2 540
5dc361e1 541 // Update all fields in the current object.
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542 $this->restore();
543 }
544
545 /**
546 * Checks if this course category is visible to current user
547 *
548 * Please note that methods coursecat::get (without 3rd argumet),
549 * coursecat::get_children(), etc. return only visible categories so it is
550 * usually not needed to call this function outside of this class
551 *
552 * @return bool
553 */
554 public function is_uservisible() {
555 return !$this->id || $this->visible ||
5dc361e1 556 has_capability('moodle/category:viewhiddencategories', $this->get_context());
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557 }
558
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559 /**
560 * Returns the complete corresponding record from DB table course_categories
561 *
562 * Mostly used in deprecated functions
563 *
564 * @return stdClass
565 */
566 public function get_db_record() {
567 global $DB;
568 if ($record = $DB->get_record('course_categories', array('id' => $this->id))) {
569 return $record;
570 } else {
571 return (object)convert_to_array($this);
572 }
573 }
574
b33389d2 575 /**
eabbfa82 576 * Returns the entry from categories tree and makes sure the application-level tree cache is built
b33389d2 577 *
eabbfa82 578 * The following keys can be requested:
b33389d2 579 *
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580 * 'countall' - total number of categories in the system (always present)
581 * 0 - array of ids of top-level categories (always present)
582 * '0i' - array of ids of top-level categories that have visible=0 (always present but may be empty array)
583 * $id (int) - array of ids of categories that are direct children of category with id $id. If
584 * category with id $id does not exist returns false. If category has no children returns empty array
585 * $id.'i' - array of ids of children categories that have visible=0
586 *
587 * @param int|string $id
588 * @return mixed
b33389d2 589 */
eabbfa82 590 protected static function get_tree($id) {
b33389d2 591 global $DB;
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592 $coursecattreecache = cache::make('core', 'coursecattree');
593 $rv = $coursecattreecache->get($id);
594 if ($rv !== false) {
595 return $rv;
596 }
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597 // Re-build the tree.
598 $sql = "SELECT cc.id, cc.parent, cc.visible
599 FROM {course_categories} cc
600 ORDER BY cc.sortorder";
601 $rs = $DB->get_recordset_sql($sql, array());
602 $all = array(0 => array(), '0i' => array());
603 $count = 0;
604 foreach ($rs as $record) {
605 $all[$record->id] = array();
606 $all[$record->id. 'i'] = array();
607 if (array_key_exists($record->parent, $all)) {
b33389d2 608 $all[$record->parent][] = $record->id;
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609 if (!$record->visible) {
610 $all[$record->parent. 'i'][] = $record->id;
611 }
612 } else {
5dc361e1 613 // Parent not found. This is data consistency error but next fix_course_sortorder() should fix it.
eabbfa82 614 $all[0][] = $record->id;
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615 if (!$record->visible) {
616 $all['0i'][] = $record->id;
617 }
b33389d2 618 }
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619 $count++;
620 }
621 $rs->close();
622 if (!$count) {
623 // No categories found.
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624 // This may happen after upgrade of a very old moodle version.
625 // In new versions the default category is created on install.
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626 $defcoursecat = self::create(array('name' => get_string('miscellaneous')));
627 set_config('defaultrequestcategory', $defcoursecat->id);
628 $all[0] = array($defcoursecat->id);
629 $all[$defcoursecat->id] = array();
630 $count++;
b33389d2 631 }
5dc361e1 632 // We must add countall to all in case it was the requested ID.
290af254 633 $all['countall'] = $count;
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634 foreach ($all as $key => $children) {
635 $coursecattreecache->set($key, $children);
636 }
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637 if (array_key_exists($id, $all)) {
638 return $all[$id];
639 }
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640 // Requested non-existing category.
641 return array();
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642 }
643
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644 /**
645 * Returns number of ALL categories in the system regardless if
646 * they are visible to current user or not
647 *
648 * @return int
649 */
15d50fff 650 public static function count_all() {
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651 return self::get_tree('countall');
652 }
653
654 /**
655 * Retrieves number of records from course_categories table
656 *
657 * Only cached fields are retrieved. Records are ready for preloading context
658 *
659 * @param string $whereclause
660 * @param array $params
661 * @return array array of stdClass objects
662 */
663 protected static function get_records($whereclause, $params) {
664 global $DB;
5dc361e1 665 // Retrieve from DB only the fields that need to be stored in cache.
93c544bd 666 $fields = array_keys(array_filter(self::$coursecatfields));
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667 $ctxselect = context_helper::get_preload_record_columns_sql('ctx');
668 $sql = "SELECT cc.". join(',cc.', $fields). ", $ctxselect
669 FROM {course_categories} cc
670 JOIN {context} ctx ON cc.id = ctx.instanceid AND ctx.contextlevel = :contextcoursecat
671 WHERE ". $whereclause." ORDER BY cc.sortorder";
672 return $DB->get_records_sql($sql,
673 array('contextcoursecat' => CONTEXT_COURSECAT) + $params);
674 }
675
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676 /**
677 * Given list of DB records from table course populates each record with list of users with course contact roles
678 *
679 * This function fills the courses with raw information as {@link get_role_users()} would do.
680 * See also {@link course_in_list::get_course_contacts()} for more readable return
681 *
682 * $courses[$i]->managers = array(
683 * $roleassignmentid => $roleuser,
684 * ...
685 * );
686 *
687 * where $roleuser is an stdClass with the following properties:
688 *
689 * $roleuser->raid - role assignment id
690 * $roleuser->id - user id
691 * $roleuser->username
692 * $roleuser->firstname
693 * $roleuser->lastname
694 * $roleuser->rolecoursealias
695 * $roleuser->rolename
696 * $roleuser->sortorder - role sortorder
697 * $roleuser->roleid
698 * $roleuser->roleshortname
699 *
700 * @todo MDL-38596 minimize number of queries to preload contacts for the list of courses
701 *
702 * @param array $courses
703 */
704 public static function preload_course_contacts(&$courses) {
705 global $CFG, $DB;
706 if (empty($courses) || empty($CFG->coursecontact)) {
707 return;
708 }
709 $managerroles = explode(',', $CFG->coursecontact);
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710 $cache = cache::make('core', 'coursecontacts');
711 $cacheddata = $cache->get_many(array_merge(array('basic'), array_keys($courses)));
5dc361e1 712 // Check if cache was set for the current course contacts and it is not yet expired.
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713 if (empty($cacheddata['basic']) || $cacheddata['basic']['roles'] !== $CFG->coursecontact ||
714 $cacheddata['basic']['lastreset'] < time() - self::CACHE_COURSE_CONTACTS_TTL) {
5dc361e1 715 // Reset cache.
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716 $keys = $DB->get_fieldset_select('course', 'id', '');
717 $cache->delete_many($keys);
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718 $cache->set('basic', array('roles' => $CFG->coursecontact, 'lastreset' => time()));
719 $cacheddata = $cache->get_many(array_merge(array('basic'), array_keys($courses)));
720 }
721 $courseids = array();
722 foreach (array_keys($courses) as $id) {
723 if ($cacheddata[$id] !== false) {
724 $courses[$id]->managers = $cacheddata[$id];
725 } else {
726 $courseids[] = $id;
727 }
728 }
31b0530a 729
5dc361e1 730 // Array $courseids now stores list of ids of courses for which we still need to retrieve contacts.
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731 if (empty($courseids)) {
732 return;
733 }
93c544bd 734
5dc361e1 735 // First build the array of all context ids of the courses and their categories.
93c544bd 736 $allcontexts = array();
31b0530a 737 foreach ($courseids as $id) {
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738 $context = context_course::instance($id);
739 $courses[$id]->managers = array();
740 foreach (preg_split('|/|', $context->path, 0, PREG_SPLIT_NO_EMPTY) as $ctxid) {
741 if (!isset($allcontexts[$ctxid])) {
742 $allcontexts[$ctxid] = array();
743 }
744 $allcontexts[$ctxid][] = $id;
745 }
746 }
747
5dc361e1 748 // Fetch list of all users with course contact roles in any of the courses contexts or parent contexts.
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749 list($sql1, $params1) = $DB->get_in_or_equal(array_keys($allcontexts), SQL_PARAMS_NAMED, 'ctxid');
750 list($sql2, $params2) = $DB->get_in_or_equal($managerroles, SQL_PARAMS_NAMED, 'rid');
751 list($sort, $sortparams) = users_order_by_sql('u');
ef4d3233 752 $notdeleted = array('notdeleted'=>0);
a327f25e 753 $allnames = get_all_user_name_fields(true, 'u');
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754 $sql = "SELECT ra.contextid, ra.id AS raid,
755 r.id AS roleid, r.name AS rolename, r.shortname AS roleshortname,
a327f25e 756 rn.name AS rolecoursealias, u.id, u.username, $allnames
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757 FROM {role_assignments} ra
758 JOIN {user} u ON ra.userid = u.id
759 JOIN {role} r ON ra.roleid = r.id
760 LEFT JOIN {role_names} rn ON (rn.contextid = ra.contextid AND rn.roleid = r.id)
ef4d3233 761 WHERE ra.contextid ". $sql1." AND ra.roleid ". $sql2." AND u.deleted = :notdeleted
93c544bd 762 ORDER BY r.sortorder, $sort";
ef4d3233 763 $rs = $DB->get_recordset_sql($sql, $params1 + $params2 + $notdeleted + $sortparams);
31b0530a 764 $checkenrolments = array();
5dc361e1 765 foreach ($rs as $ra) {
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766 foreach ($allcontexts[$ra->contextid] as $id) {
767 $courses[$id]->managers[$ra->raid] = $ra;
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768 if (!isset($checkenrolments[$id])) {
769 $checkenrolments[$id] = array();
770 }
771 $checkenrolments[$id][] = $ra->id;
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772 }
773 }
774 $rs->close();
31b0530a 775
5dc361e1 776 // Remove from course contacts users who are not enrolled in the course.
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777 $enrolleduserids = self::ensure_users_enrolled($checkenrolments);
778 foreach ($checkenrolments as $id => $userids) {
779 if (empty($enrolleduserids[$id])) {
780 $courses[$id]->managers = array();
781 } else if ($notenrolled = array_diff($userids, $enrolleduserids[$id])) {
782 foreach ($courses[$id]->managers as $raid => $ra) {
783 if (in_array($ra->id, $notenrolled)) {
784 unset($courses[$id]->managers[$raid]);
785 }
786 }
787 }
788 }
36ba8fde 789
5dc361e1 790 // Set the cache.
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791 $values = array();
792 foreach ($courseids as $id) {
793 $values[$id] = $courses[$id]->managers;
794 }
795 $cache->set_many($values);
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796 }
797
798 /**
799 * Verify user enrollments for multiple course-user combinations
800 *
801 * @param array $courseusers array where keys are course ids and values are array
802 * of users in this course whose enrolment we wish to verify
803 * @return array same structure as input array but values list only users from input
804 * who are enrolled in the course
805 */
806 protected static function ensure_users_enrolled($courseusers) {
807 global $DB;
5dc361e1 808 // If the input array is too big, split it into chunks.
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809 $maxcoursesinquery = 20;
810 if (count($courseusers) > $maxcoursesinquery) {
811 $rv = array();
812 for ($offset = 0; $offset < count($courseusers); $offset += $maxcoursesinquery) {
813 $chunk = array_slice($courseusers, $offset, $maxcoursesinquery, true);
814 $rv = $rv + self::ensure_users_enrolled($chunk);
815 }
816 return $rv;
817 }
818
5dc361e1 819 // Create a query verifying valid user enrolments for the number of courses.
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820 $sql = "SELECT DISTINCT e.courseid, ue.userid
821 FROM {user_enrolments} ue
822 JOIN {enrol} e ON e.id = ue.enrolid
823 WHERE ue.status = :active
824 AND e.status = :enabled
825 AND ue.timestart < :now1 AND (ue.timeend = 0 OR ue.timeend > :now2)";
5dc361e1 826 $now = round(time(), -2); // Rounding helps caching in DB.
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827 $params = array('enabled' => ENROL_INSTANCE_ENABLED,
828 'active' => ENROL_USER_ACTIVE,
829 'now1' => $now, 'now2' => $now);
830 $cnt = 0;
831 $subsqls = array();
832 $enrolled = array();
833 foreach ($courseusers as $id => $userids) {
834 $enrolled[$id] = array();
835 if (count($userids)) {
836 list($sql2, $params2) = $DB->get_in_or_equal($userids, SQL_PARAMS_NAMED, 'userid'.$cnt.'_');
837 $subsqls[] = "(e.courseid = :courseid$cnt AND ue.userid ".$sql2.")";
838 $params = $params + array('courseid'.$cnt => $id) + $params2;
839 $cnt++;
840 }
841 }
842 if (count($subsqls)) {
843 $sql .= "AND (". join(' OR ', $subsqls).")";
844 $rs = $DB->get_recordset_sql($sql, $params);
845 foreach ($rs as $record) {
846 $enrolled[$record->courseid][] = $record->userid;
847 }
848 $rs->close();
93c544bd 849 }
31b0530a 850 return $enrolled;
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851 }
852
853 /**
854 * Retrieves number of records from course table
855 *
856 * Not all fields are retrieved. Records are ready for preloading context
857 *
858 * @param string $whereclause
859 * @param array $params
860 * @param array $options may indicate that summary and/or coursecontacts need to be retrieved
861 * @param bool $checkvisibility if true, capability 'moodle/course:viewhiddencourses' will be checked
862 * on not visible courses
863 * @return array array of stdClass objects
864 */
865 protected static function get_course_records($whereclause, $params, $options, $checkvisibility = false) {
866 global $DB;
867 $ctxselect = context_helper::get_preload_record_columns_sql('ctx');
868 $fields = array('c.id', 'c.category', 'c.sortorder',
869 'c.shortname', 'c.fullname', 'c.idnumber',
4a3fb71c 870 'c.startdate', 'c.visible', 'c.cacherev');
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871 if (!empty($options['summary'])) {
872 $fields[] = 'c.summary';
873 $fields[] = 'c.summaryformat';
874 } else {
d0ed33d6 875 $fields[] = $DB->sql_substr('c.summary', 1, 1). ' as hassummary';
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876 }
877 $sql = "SELECT ". join(',', $fields). ", $ctxselect
878 FROM {course} c
879 JOIN {context} ctx ON c.id = ctx.instanceid AND ctx.contextlevel = :contextcourse
880 WHERE ". $whereclause." ORDER BY c.sortorder";
881 $list = $DB->get_records_sql($sql,
882 array('contextcourse' => CONTEXT_COURSE) + $params);
883
884 if ($checkvisibility) {
885 // Loop through all records and make sure we only return the courses accessible by user.
886 foreach ($list as $course) {
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887 if (isset($list[$course->id]->hassummary)) {
888 $list[$course->id]->hassummary = strlen($list[$course->id]->hassummary) > 0;
889 }
93c544bd 890 if (empty($course->visible)) {
5dc361e1 891 // Load context only if we need to check capability.
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892 context_helper::preload_from_record($course);
893 if (!has_capability('moodle/course:viewhiddencourses', context_course::instance($course->id))) {
894 unset($list[$course->id]);
895 }
896 }
897 }
898 }
899
5dc361e1 900 // Preload course contacts if necessary.
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901 if (!empty($options['coursecontacts'])) {
902 self::preload_course_contacts($list);
903 }
904 return $list;
905 }
906
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907 /**
908 * Returns array of ids of children categories that current user can not see
909 *
910 * This data is cached in user session cache
911 *
912 * @return array
913 */
914 protected function get_not_visible_children_ids() {
915 global $DB;
916 $coursecatcache = cache::make('core', 'coursecat');
917 if (($invisibleids = $coursecatcache->get('ic'. $this->id)) === false) {
5dc361e1 918 // We never checked visible children before.
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919 $hidden = self::get_tree($this->id.'i');
920 $invisibleids = array();
921 if ($hidden) {
5dc361e1 922 // Preload categories contexts.
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923 list($sql, $params) = $DB->get_in_or_equal($hidden, SQL_PARAMS_NAMED, 'id');
924 $ctxselect = context_helper::get_preload_record_columns_sql('ctx');
925 $contexts = $DB->get_records_sql("SELECT $ctxselect FROM {context} ctx
926 WHERE ctx.contextlevel = :contextcoursecat AND ctx.instanceid ".$sql,
927 array('contextcoursecat' => CONTEXT_COURSECAT) + $params);
928 foreach ($contexts as $record) {
929 context_helper::preload_from_record($record);
930 }
5dc361e1 931 // Check that user has 'viewhiddencategories' capability for each hidden category.
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932 foreach ($hidden as $id) {
933 if (!has_capability('moodle/category:viewhiddencategories', context_coursecat::instance($id))) {
934 $invisibleids[] = $id;
935 }
936 }
937 }
938 $coursecatcache->set('ic'. $this->id, $invisibleids);
939 }
940 return $invisibleids;
941 }
942
943 /**
93c544bd 944 * Sorts list of records by several fields
eabbfa82 945 *
93c544bd 946 * @param array $records array of stdClass objects
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947 * @param array $sortfields assoc array where key is the field to sort and value is 1 for asc or -1 for desc
948 * @return int
949 */
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950 protected static function sort_records(&$records, $sortfields) {
951 if (empty($records)) {
952 return;
953 }
5dc361e1 954 // If sorting by course display name, calculate it (it may be fullname or shortname+fullname).
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955 if (array_key_exists('displayname', $sortfields)) {
956 foreach ($records as $key => $record) {
957 if (!isset($record->displayname)) {
958 $records[$key]->displayname = get_course_display_name_for_list($record);
eabbfa82 959 }
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960 }
961 }
5dc361e1 962 // Sorting by one field - use core_collator.
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963 if (count($sortfields) == 1) {
964 $property = key($sortfields);
965 if (in_array($property, array('sortorder', 'id', 'visible', 'parent', 'depth'))) {
2f1e464a 966 $sortflag = core_collator::SORT_NUMERIC;
93c544bd 967 } else if (in_array($property, array('idnumber', 'displayname', 'name', 'shortname', 'fullname'))) {
2f1e464a 968 $sortflag = core_collator::SORT_STRING;
eabbfa82 969 } else {
2f1e464a 970 $sortflag = core_collator::SORT_REGULAR;
93c544bd 971 }
2f1e464a 972 core_collator::asort_objects_by_property($records, $property, $sortflag);
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973 if ($sortfields[$property] < 0) {
974 $records = array_reverse($records, true);
975 }
976 return;
977 }
15f89e28 978 $records = coursecat_sortable_records::sort($records, $sortfields);
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979 }
980
981 /**
982 * Returns array of children categories visible to the current user
983 *
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984 * @param array $options options for retrieving children
985 * - sort - list of fields to sort. Example
986 * array('idnumber' => 1, 'name' => 1, 'id' => -1)
987 * will sort by idnumber asc, name asc and id desc.
988 * Default: array('sortorder' => 1)
989 * Only cached fields may be used for sorting!
990 * - offset
991 * - limit - maximum number of children to return, 0 or null for no limit
5dc361e1 992 * @return coursecat[] Array of coursecat objects indexed by category id
b33389d2 993 */
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994 public function get_children($options = array()) {
995 global $DB;
996 $coursecatcache = cache::make('core', 'coursecat');
997
5dc361e1 998 // Get default values for options.
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999 if (!empty($options['sort']) && is_array($options['sort'])) {
1000 $sortfields = $options['sort'];
1001 } else {
1002 $sortfields = array('sortorder' => 1);
1003 }
1004 $limit = null;
1005 if (!empty($options['limit']) && (int)$options['limit']) {
1006 $limit = (int)$options['limit'];
1007 }
1008 $offset = 0;
1009 if (!empty($options['offset']) && (int)$options['offset']) {
1010 $offset = (int)$options['offset'];
1011 }
1012
5dc361e1 1013 // First retrieve list of user-visible and sorted children ids from cache.
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1014 $sortedids = $coursecatcache->get('c'. $this->id. ':'. serialize($sortfields));
1015 if ($sortedids === false) {
1016 $sortfieldskeys = array_keys($sortfields);
1017 if ($sortfieldskeys[0] === 'sortorder') {
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1018 // No DB requests required to build the list of ids sorted by sortorder.
1019 // We can easily ignore other sort fields because sortorder is always different.
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1020 $sortedids = self::get_tree($this->id);
1021 if ($sortedids && ($invisibleids = $this->get_not_visible_children_ids())) {
1022 $sortedids = array_diff($sortedids, $invisibleids);
1023 if ($sortfields['sortorder'] == -1) {
1024 $sortedids = array_reverse($sortedids, true);
1025 }
b33389d2 1026 }
eabbfa82 1027 } else {
5dc361e1 1028 // We need to retrieve and sort all children. Good thing that it is done only on first request.
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1029 if ($invisibleids = $this->get_not_visible_children_ids()) {
1030 list($sql, $params) = $DB->get_in_or_equal($invisibleids, SQL_PARAMS_NAMED, 'id', false);
1031 $records = self::get_records('cc.parent = :parent AND cc.id '. $sql,
1032 array('parent' => $this->id) + $params);
1033 } else {
1034 $records = self::get_records('cc.parent = :parent', array('parent' => $this->id));
1035 }
93c544bd 1036 self::sort_records($records, $sortfields);
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1037 $sortedids = array_keys($records);
1038 }
1039 $coursecatcache->set('c'. $this->id. ':'.serialize($sortfields), $sortedids);
1040 }
1041
1042 if (empty($sortedids)) {
1043 return array();
1044 }
1045
5dc361e1 1046 // Now retrieive and return categories.
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1047 if ($offset || $limit) {
1048 $sortedids = array_slice($sortedids, $offset, $limit);
1049 }
1050 if (isset($records)) {
5dc361e1 1051 // Easy, we have already retrieved records.
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1052 if ($offset || $limit) {
1053 $records = array_slice($records, $offset, $limit, true);
1054 }
1055 } else {
1056 list($sql, $params) = $DB->get_in_or_equal($sortedids, SQL_PARAMS_NAMED, 'id');
5dc361e1 1057 $records = self::get_records('cc.id '. $sql, array('parent' => $this->id) + $params);
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1058 }
1059
1060 $rv = array();
1061 foreach ($sortedids as $id) {
1062 if (isset($records[$id])) {
1063 $rv[$id] = new coursecat($records[$id]);
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1064 }
1065 }
1066 return $rv;
1067 }
1068
5dc361e1 1069 /**
67e1f268
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1070 * Returns true if the user has the manage capability on any category.
1071 *
1072 * This method uses the coursecat cache and an entry `has_manage_capability` to speed up
1073 * calls to this method.
1074 *
5dc361e1
SH
1075 * @return bool
1076 */
b488058f 1077 public static function has_manage_capability_on_any() {
484c4c6c
SH
1078 return self::has_capability_on_any('moodle/category:manage');
1079 }
1080
1081 /**
1082 * Checks if the user has at least one of the given capabilities on any category.
1083 *
1084 * @param array|string $capabilities One or more capabilities to check. Check made is an OR.
1085 * @return bool
1086 */
1087 public static function has_capability_on_any($capabilities) {
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SH
1088 global $DB;
1089 if (!isloggedin() || isguestuser()) {
1090 return false;
1091 }
484c4c6c
SH
1092
1093 if (!is_array($capabilities)) {
1094 $capabilities = array($capabilities);
1095 }
1096 $keys = array();
1097 foreach ($capabilities as $capability) {
1098 $keys[$capability] = sha1($capability);
1099 }
1100
1101 /* @var cache_session $cache */
5dc361e1 1102 $cache = cache::make('core', 'coursecat');
484c4c6c
SH
1103 $hascapability = $cache->get_many($keys);
1104 $needtoload = false;
1105 foreach ($hascapability as $capability) {
1106 if ($capability === '1') {
1107 return true;
1108 } else if ($capability === false) {
1109 $needtoload = true;
1110 }
1111 }
1112 if ($needtoload === false) {
1113 // All capabilities were retrieved and the user didn't have any.
1114 return false;
5dc361e1 1115 }
67e1f268 1116
484c4c6c 1117 $haskey = null;
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SH
1118 $fields = context_helper::get_preload_record_columns_sql('ctx');
1119 $sql = "SELECT ctx.instanceid AS categoryid, $fields
5dc361e1
SH
1120 FROM {context} ctx
1121 WHERE contextlevel = :contextlevel
1122 ORDER BY depth ASC";
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1123 $params = array('contextlevel' => CONTEXT_COURSECAT);
1124 $recordset = $DB->get_recordset_sql($sql, $params);
1125 foreach ($recordset as $context) {
1126 context_helper::preload_from_record($context);
1127 $context = context_coursecat::instance($context->categoryid);
484c4c6c
SH
1128 foreach ($capabilities as $capability) {
1129 if (has_capability($capability, $context)) {
1130 $haskey = $capability;
1131 break 2;
1132 }
5dc361e1 1133 }
5dc361e1 1134 }
67e1f268 1135 $recordset->close();
484c4c6c
SH
1136 if ($haskey === null) {
1137 $data = array();
1138 foreach ($keys as $key) {
1139 $data[$key] = '0';
1140 }
1141 $cache->set_many($data);
1142 return false;
1143 } else {
1144 $cache->set($haskey, '1');
1145 return true;
1146 }
5dc361e1
SH
1147 }
1148
1149 /**
67e1f268
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1150 * Returns true if the user can resort any category.
1151 * @return bool
1152 */
1153 public static function can_resort_any() {
1154 return self::has_manage_capability_on_any();
1155 }
1156
1157 /**
1158 * Returns true if the user can change the parent of any category.
5dc361e1
SH
1159 * @return bool
1160 */
1161 public static function can_change_parent_any() {
67e1f268 1162 return self::has_manage_capability_on_any();
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1163 }
1164
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1165 /**
1166 * Returns number of subcategories visible to the current user
1167 *
1168 * @return int
1169 */
1170 public function get_children_count() {
1171 $sortedids = self::get_tree($this->id);
1172 $invisibleids = $this->get_not_visible_children_ids();
1173 return count($sortedids) - count($invisibleids);
1174 }
1175
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1176 /**
1177 * Returns true if the category has ANY children, including those not visible to the user
1178 *
1179 * @return boolean
1180 */
1181 public function has_children() {
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1182 $allchildren = self::get_tree($this->id);
1183 return !empty($allchildren);
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1184 }
1185
1186 /**
1187 * Returns true if the category has courses in it (count does not include courses
1188 * in child categories)
1189 *
1190 * @return bool
1191 */
1192 public function has_courses() {
1193 global $DB;
1194 return $DB->record_exists_sql("select 1 from {course} where category = ?",
1195 array($this->id));
1196 }
1197
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1198 /**
1199 * Searches courses
1200 *
1201 * List of found course ids is cached for 10 minutes. Cache may be purged prior
1202 * to this when somebody edits courses or categories, however it is very
1203 * difficult to keep track of all possible changes that may affect list of courses.
1204 *
1205 * @param array $search contains search criterias, such as:
1206 * - search - search string
1207 * - blocklist - id of block (if we are searching for courses containing specific block0
1208 * - modulelist - name of module (if we are searching for courses containing specific module
1209 * - tagid - id of tag
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1210 * @param array $options display options, same as in get_courses() except 'recursive' is ignored -
1211 * search is always category-independent
85708da6 1212 * @return course_in_list[]
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1213 */
1214 public static function search_courses($search, $options = array()) {
1215 global $DB;
1216 $offset = !empty($options['offset']) ? $options['offset'] : 0;
1217 $limit = !empty($options['limit']) ? $options['limit'] : null;
1218 $sortfields = !empty($options['sort']) ? $options['sort'] : array('sortorder' => 1);
1219
1220 $coursecatcache = cache::make('core', 'coursecat');
1221 $cachekey = 's-'. serialize($search + array('sort' => $sortfields));
1222 $cntcachekey = 'scnt-'. serialize($search);
1223
1224 $ids = $coursecatcache->get($cachekey);
1225 if ($ids !== false) {
5dc361e1 1226 // We already cached last search result.
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1227 $ids = array_slice($ids, $offset, $limit);
1228 $courses = array();
1229 if (!empty($ids)) {
1230 list($sql, $params) = $DB->get_in_or_equal($ids, SQL_PARAMS_NAMED, 'id');
1231 $records = self::get_course_records("c.id ". $sql, $params, $options);
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1232 // Preload course contacts if necessary - saves DB queries later to do it for each course separately.
1233 if (!empty($options['coursecontacts'])) {
1234 self::preload_course_contacts($records);
1235 }
1236 // If option 'idonly' is specified no further action is needed, just return list of ids.
1237 if (!empty($options['idonly'])) {
1238 return array_keys($records);
1239 }
1240 // Prepare the list of course_in_list objects.
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1241 foreach ($ids as $id) {
1242 $courses[$id] = new course_in_list($records[$id]);
1243 }
1244 }
1245 return $courses;
1246 }
1247
1248 $preloadcoursecontacts = !empty($options['coursecontacts']);
1249 unset($options['coursecontacts']);
1250
1251 if (!empty($search['search'])) {
5dc361e1 1252 // Search courses that have specified words in their names/summaries.
93c544bd 1253 $searchterms = preg_split('|\s+|', trim($search['search']), 0, PREG_SPLIT_NO_EMPTY);
15f89e28 1254 $searchterms = array_filter($searchterms, create_function('$v', 'return strlen($v) > 1;'));
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1255 $courselist = get_courses_search($searchterms, 'c.sortorder ASC', 0, 9999999, $totalcount);
1256 self::sort_records($courselist, $sortfields);
1257 $coursecatcache->set($cachekey, array_keys($courselist));
1258 $coursecatcache->set($cntcachekey, $totalcount);
1259 $records = array_slice($courselist, $offset, $limit, true);
1260 } else {
1261 if (!empty($search['blocklist'])) {
5dc361e1 1262 // Search courses that have block with specified id.
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1263 $blockname = $DB->get_field('block', 'name', array('id' => $search['blocklist']));
1264 $where = 'ctx.id in (SELECT distinct bi.parentcontextid FROM {block_instances} bi
1265 WHERE bi.blockname = :blockname)';
1266 $params = array('blockname' => $blockname);
1267 } else if (!empty($search['modulelist'])) {
5dc361e1 1268 // Search courses that have module with specified name.
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1269 $where = "c.id IN (SELECT DISTINCT module.course ".
1270 "FROM {".$search['modulelist']."} module)";
1271 $params = array();
1272 } else if (!empty($search['tagid'])) {
5dc361e1 1273 // Search courses that are tagged with the specified tag.
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1274 $where = "c.id IN (SELECT t.itemid ".
1275 "FROM {tag_instance} t WHERE t.tagid = :tagid AND t.itemtype = :itemtype)";
1276 $params = array('tagid' => $search['tagid'], 'itemtype' => 'course');
1277 } else {
1278 debugging('No criteria is specified while searching courses', DEBUG_DEVELOPER);
1279 return array();
1280 }
1281 $courselist = self::get_course_records($where, $params, $options, true);
1282 self::sort_records($courselist, $sortfields);
1283 $coursecatcache->set($cachekey, array_keys($courselist));
1284 $coursecatcache->set($cntcachekey, count($courselist));
1285 $records = array_slice($courselist, $offset, $limit, true);
1286 }
1287
1288 // Preload course contacts if necessary - saves DB queries later to do it for each course separately.
1289 if (!empty($preloadcoursecontacts)) {
1290 self::preload_course_contacts($records);
1291 }
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1292 // If option 'idonly' is specified no further action is needed, just return list of ids.
1293 if (!empty($options['idonly'])) {
1294 return array_keys($records);
1295 }
1296 // Prepare the list of course_in_list objects.
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1297 $courses = array();
1298 foreach ($records as $record) {
1299 $courses[$record->id] = new course_in_list($record);
1300 }
1301 return $courses;
1302 }
1303
1304 /**
1305 * Returns number of courses in the search results
1306 *
1307 * It is recommended to call this function after {@link coursecat::search_courses()}
1308 * and not before because only course ids are cached. Otherwise search_courses() may
1309 * perform extra DB queries.
1310 *
1311 * @param array $search search criteria, see method search_courses() for more details
1312 * @param array $options display options. They do not affect the result but
1313 * the 'sort' property is used in cache key for storing list of course ids
1314 * @return int
1315 */
1316 public static function search_courses_count($search, $options = array()) {
1317 $coursecatcache = cache::make('core', 'coursecat');
1318 $cntcachekey = 'scnt-'. serialize($search);
1319 if (($cnt = $coursecatcache->get($cntcachekey)) === false) {
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1320 // Cached value not found. Retrieve ALL courses and return their count.
1321 unset($options['offset']);
1322 unset($options['limit']);
1323 unset($options['summary']);
1324 unset($options['coursecontacts']);
bf1405a6 1325 $options['idonly'] = true;
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1326 $courses = self::search_courses($search, $options);
1327 $cnt = count($courses);
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1328 }
1329 return $cnt;
1330 }
1331
1332 /**
1333 * Retrieves the list of courses accessible by user
1334 *
1335 * Not all information is cached, try to avoid calling this method
1336 * twice in the same request.
1337 *
1338 * The following fields are always retrieved:
1339 * - id, visible, fullname, shortname, idnumber, category, sortorder
1340 *
1341 * If you plan to use properties/methods course_in_list::$summary and/or
1342 * course_in_list::get_course_contacts()
1343 * you can preload this information using appropriate 'options'. Otherwise
1344 * they will be retrieved from DB on demand and it may end with bigger DB load.
1345 *
1346 * Note that method course_in_list::has_summary() will not perform additional
1347 * DB queries even if $options['summary'] is not specified
1348 *
1349 * List of found course ids is cached for 10 minutes. Cache may be purged prior
1350 * to this when somebody edits courses or categories, however it is very
1351 * difficult to keep track of all possible changes that may affect list of courses.
1352 *
1353 * @param array $options options for retrieving children
1354 * - recursive - return courses from subcategories as well. Use with care,
1355 * this may be a huge list!
1356 * - summary - preloads fields 'summary' and 'summaryformat'
1357 * - coursecontacts - preloads course contacts
1358 * - sort - list of fields to sort. Example
1359 * array('idnumber' => 1, 'shortname' => 1, 'id' => -1)
1360 * will sort by idnumber asc, shortname asc and id desc.
1361 * Default: array('sortorder' => 1)
1362 * Only cached fields may be used for sorting!
1363 * - offset
1364 * - limit - maximum number of children to return, 0 or null for no limit
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1365 * - idonly - returns the array or course ids instead of array of objects
1366 * used only in get_courses_count()
85708da6 1367 * @return course_in_list[]
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1368 */
1369 public function get_courses($options = array()) {
1370 global $DB;
1371 $recursive = !empty($options['recursive']);
1372 $offset = !empty($options['offset']) ? $options['offset'] : 0;
1373 $limit = !empty($options['limit']) ? $options['limit'] : null;
1374 $sortfields = !empty($options['sort']) ? $options['sort'] : array('sortorder' => 1);
1375
1376 // Check if this category is hidden.
1377 // Also 0-category never has courses unless this is recursive call.
1378 if (!$this->is_uservisible() || (!$this->id && !$recursive)) {
1379 return array();
1380 }
1381
1382 $coursecatcache = cache::make('core', 'coursecat');
1383 $cachekey = 'l-'. $this->id. '-'. (!empty($options['recursive']) ? 'r' : '').
1384 '-'. serialize($sortfields);
1385 $cntcachekey = 'lcnt-'. $this->id. '-'. (!empty($options['recursive']) ? 'r' : '');
1386
5dc361e1 1387 // Check if we have already cached results.
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1388 $ids = $coursecatcache->get($cachekey);
1389 if ($ids !== false) {
5dc361e1 1390 // We already cached last search result and it did not expire yet.
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1391 $ids = array_slice($ids, $offset, $limit);
1392 $courses = array();
1393 if (!empty($ids)) {
1394 list($sql, $params) = $DB->get_in_or_equal($ids, SQL_PARAMS_NAMED, 'id');
1395 $records = self::get_course_records("c.id ". $sql, $params, $options);
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1396 // Preload course contacts if necessary - saves DB queries later to do it for each course separately.
1397 if (!empty($options['coursecontacts'])) {
1398 self::preload_course_contacts($records);
1399 }
1400 // If option 'idonly' is specified no further action is needed, just return list of ids.
1401 if (!empty($options['idonly'])) {
1402 return array_keys($records);
1403 }
1404 // Prepare the list of course_in_list objects.
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1405 foreach ($ids as $id) {
1406 $courses[$id] = new course_in_list($records[$id]);
1407 }
1408 }
1409 return $courses;
1410 }
1411
5dc361e1 1412 // Retrieve list of courses in category.
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1413 $where = 'c.id <> :siteid';
1414 $params = array('siteid' => SITEID);
1415 if ($recursive) {
1416 if ($this->id) {
5db8f5a8 1417 $context = context_coursecat::instance($this->id);
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1418 $where .= ' AND ctx.path like :path';
1419 $params['path'] = $context->path. '/%';
1420 }
1421 } else {
1422 $where .= ' AND c.category = :categoryid';
1423 $params['categoryid'] = $this->id;
1424 }
5dc361e1 1425 // Get list of courses without preloaded coursecontacts because we don't need them for every course.
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1426 $list = $this->get_course_records($where, $params, array_diff_key($options, array('coursecontacts' => 1)), true);
1427
5dc361e1 1428 // Sort and cache list.
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1429 self::sort_records($list, $sortfields);
1430 $coursecatcache->set($cachekey, array_keys($list));
1431 $coursecatcache->set($cntcachekey, count($list));
1432
1433 // Apply offset/limit, convert to course_in_list and return.
1434 $courses = array();
1435 if (isset($list)) {
1436 if ($offset || $limit) {
1437 $list = array_slice($list, $offset, $limit, true);
1438 }
1439 // Preload course contacts if necessary - saves DB queries later to do it for each course separately.
1440 if (!empty($options['coursecontacts'])) {
1441 self::preload_course_contacts($list);
1442 }
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1443 // If option 'idonly' is specified no further action is needed, just return list of ids.
1444 if (!empty($options['idonly'])) {
1445 return array_keys($list);
1446 }
1447 // Prepare the list of course_in_list objects.
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1448 foreach ($list as $record) {
1449 $courses[$record->id] = new course_in_list($record);
1450 }
1451 }
1452 return $courses;
1453 }
1454
1455 /**
1456 * Returns number of courses visible to the user
1457 *
1458 * @param array $options similar to get_courses() except some options do not affect
1459 * number of courses (i.e. sort, summary, offset, limit etc.)
1460 * @return int
1461 */
1462 public function get_courses_count($options = array()) {
1463 $cntcachekey = 'lcnt-'. $this->id. '-'. (!empty($options['recursive']) ? 'r' : '');
1464 $coursecatcache = cache::make('core', 'coursecat');
1465 if (($cnt = $coursecatcache->get($cntcachekey)) === false) {
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1466 // Cached value not found. Retrieve ALL courses and return their count.
1467 unset($options['offset']);
1468 unset($options['limit']);
1469 unset($options['summary']);
1470 unset($options['coursecontacts']);
bf1405a6 1471 $options['idonly'] = true;
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1472 $courses = $this->get_courses($options);
1473 $cnt = count($courses);
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1474 }
1475 return $cnt;
1476 }
1477
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1478 /**
1479 * Returns true if the user is able to delete this category.
1480 *
1481 * Note if this category contains any courses this isn't a full check, it will need to be accompanied by a call to either
1482 * {@link coursecat::can_delete_full()} or {@link coursecat::can_move_content_to()} depending upon what the user wished to do.
1483 *
1484 * @return boolean
1485 */
1486 public function can_delete() {
1487 if (!$this->has_manage_capability()) {
1488 return false;
1489 }
1490 return $this->parent_has_manage_capability();
1491 }
1492
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1493 /**
1494 * Returns true if user can delete current category and all its contents
1495 *
1496 * To be able to delete course category the user must have permission
1497 * 'moodle/category:manage' in ALL child course categories AND
1498 * be able to delete all courses
1499 *
1500 * @return bool
1501 */
1502 public function can_delete_full() {
1503 global $DB;
1504 if (!$this->id) {
5dc361e1 1505 // Fool-proof.
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1506 return false;
1507 }
1508
5dc361e1 1509 $context = $this->get_context();
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1510 if (!$this->is_uservisible() ||
1511 !has_capability('moodle/category:manage', $context)) {
1512 return false;
1513 }
1514
5dc361e1 1515 // Check all child categories (not only direct children).
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1516 $sql = context_helper::get_preload_record_columns_sql('ctx');
1517 $childcategories = $DB->get_records_sql('SELECT c.id, c.visible, '. $sql.
1518 ' FROM {context} ctx '.
1519 ' JOIN {course_categories} c ON c.id = ctx.instanceid'.
1520 ' WHERE ctx.path like ? AND ctx.contextlevel = ?',
1521 array($context->path. '/%', CONTEXT_COURSECAT));
1522 foreach ($childcategories as $childcat) {
1523 context_helper::preload_from_record($childcat);
1524 $childcontext = context_coursecat::instance($childcat->id);
1525 if ((!$childcat->visible && !has_capability('moodle/category:viewhiddencategories', $childcontext)) ||
1526 !has_capability('moodle/category:manage', $childcontext)) {
1527 return false;
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1528 }
1529 }
1530
5dc361e1 1531 // Check courses.
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1532 $sql = context_helper::get_preload_record_columns_sql('ctx');
1533 $coursescontexts = $DB->get_records_sql('SELECT ctx.instanceid AS courseid, '.
1534 $sql. ' FROM {context} ctx '.
1535 'WHERE ctx.path like :pathmask and ctx.contextlevel = :courselevel',
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1536 array('pathmask' => $context->path. '/%',
1537 'courselevel' => CONTEXT_COURSE));
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1538 foreach ($coursescontexts as $ctxrecord) {
1539 context_helper::preload_from_record($ctxrecord);
1540 if (!can_delete_course($ctxrecord->courseid)) {
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1541 return false;
1542 }
1543 }
1544
1545 return true;
1546 }
1547
1548 /**
1549 * Recursively delete category including all subcategories and courses
1550 *
1551 * Function {@link coursecat::can_delete_full()} MUST be called prior
1552 * to calling this function because there is no capability check
1553 * inside this function
1554 *
1555 * @param boolean $showfeedback display some notices
1556 * @return array return deleted courses
5dc361e1 1557 * @throws moodle_exception
b33389d2 1558 */
15d50fff 1559 public function delete_full($showfeedback = true) {
b33389d2 1560 global $CFG, $DB;
f326c5b4 1561
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1562 require_once($CFG->libdir.'/gradelib.php');
1563 require_once($CFG->libdir.'/questionlib.php');
1564 require_once($CFG->dirroot.'/cohort/lib.php');
1565
1566 $deletedcourses = array();
1567
5dc361e1 1568 // Get children. Note, we don't want to use cache here because it would be rebuilt too often.
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1569 $children = $DB->get_records('course_categories', array('parent' => $this->id), 'sortorder ASC');
1570 foreach ($children as $record) {
1571 $coursecat = new coursecat($record);
1572 $deletedcourses += $coursecat->delete_full($showfeedback);
1573 }
1574
1575 if ($courses = $DB->get_records('course', array('category' => $this->id), 'sortorder ASC')) {
1576 foreach ($courses as $course) {
1577 if (!delete_course($course, false)) {
1578 throw new moodle_exception('cannotdeletecategorycourse', '', '', $course->shortname);
1579 }
1580 $deletedcourses[] = $course;
1581 }
1582 }
1583
5dc361e1 1584 // Move or delete cohorts in this context.
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1585 cohort_delete_category($this);
1586
5dc361e1 1587 // Now delete anything that may depend on course category context.
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1588 grade_course_category_delete($this->id, 0, $showfeedback);
1589 if (!question_delete_course_category($this, 0, $showfeedback)) {
1590 throw new moodle_exception('cannotdeletecategoryquestions', '', '', $this->get_formatted_name());
1591 }
1592
5dc361e1 1593 // Finally delete the category and it's context.
b33389d2 1594 $DB->delete_records('course_categories', array('id' => $this->id));
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1595
1596 $coursecatcontext = context_coursecat::instance($this->id);
1597 $coursecatcontext->delete();
b33389d2 1598
eabbfa82 1599 cache_helper::purge_by_event('changesincoursecat');
b33389d2 1600
f326c5b4 1601 // Trigger a course category deleted event.
5dc361e1 1602 /* @var \core\event\course_category_deleted $event */
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1603 $event = \core\event\course_category_deleted::create(array(
1604 'objectid' => $this->id,
1605 'context' => $coursecatcontext,
1606 'other' => array('name' => $this->name)
1607 ));
24c32bdf 1608 $event->set_coursecat($this);
f326c5b4 1609 $event->trigger();
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1610
1611 // If we deleted $CFG->defaultrequestcategory, make it point somewhere else.
1612 if ($this->id == $CFG->defaultrequestcategory) {
1613 set_config('defaultrequestcategory', $DB->get_field('course_categories', 'MIN(id)', array('parent' => 0)));
1614 }
1615 return $deletedcourses;
1616 }
1617
1618 /**
1619 * Checks if user can delete this category and move content (courses, subcategories and questions)
1620 * to another category. If yes returns the array of possible target categories names
1621 *
1622 * If user can not manage this category or it is completely empty - empty array will be returned
1623 *
1624 * @return array
1625 */
1626 public function move_content_targets_list() {
1627 global $CFG;
1628 require_once($CFG->libdir . '/questionlib.php');
5dc361e1 1629 $context = $this->get_context();
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1630 if (!$this->is_uservisible() ||
1631 !has_capability('moodle/category:manage', $context)) {
1632 // User is not able to manage current category, he is not able to delete it.
1633 // No possible target categories.
1634 return array();
1635 }
1636
1637 $testcaps = array();
1638 // If this category has courses in it, user must have 'course:create' capability in target category.
1639 if ($this->has_courses()) {
1640 $testcaps[] = 'moodle/course:create';
1641 }
1642 // If this category has subcategories or questions, user must have 'category:manage' capability in target category.
1643 if ($this->has_children() || question_context_has_any_questions($context)) {
1644 $testcaps[] = 'moodle/category:manage';
1645 }
1646 if (!empty($testcaps)) {
5dc361e1 1647 // Return list of categories excluding this one and it's children.
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1648 return self::make_categories_list($testcaps, $this->id);
1649 }
1650
1651 // Category is completely empty, no need in target for contents.
1652 return array();
1653 }
1654
1655 /**
1656 * Checks if user has capability to move all category content to the new parent before
1657 * removing this category
1658 *
1659 * @param int $newcatid
1660 * @return bool
1661 */
1662 public function can_move_content_to($newcatid) {
1663 global $CFG;
1664 require_once($CFG->libdir . '/questionlib.php');
5dc361e1 1665 $context = $this->get_context();
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1666 if (!$this->is_uservisible() ||
1667 !has_capability('moodle/category:manage', $context)) {
1668 return false;
1669 }
1670 $testcaps = array();
1671 // If this category has courses in it, user must have 'course:create' capability in target category.
1672 if ($this->has_courses()) {
1673 $testcaps[] = 'moodle/course:create';
1674 }
1675 // If this category has subcategories or questions, user must have 'category:manage' capability in target category.
1676 if ($this->has_children() || question_context_has_any_questions($context)) {
1677 $testcaps[] = 'moodle/category:manage';
1678 }
1679 if (!empty($testcaps)) {
1680 return has_all_capabilities($testcaps, context_coursecat::instance($newcatid));
1681 }
1682
5dc361e1 1683 // There is no content but still return true.
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1684 return true;
1685 }
1686
1687 /**
1688 * Deletes a category and moves all content (children, courses and questions) to the new parent
1689 *
1690 * Note that this function does not check capabilities, {@link coursecat::can_move_content_to()}
1691 * must be called prior
1692 *
1693 * @param int $newparentid
1694 * @param bool $showfeedback
1695 * @return bool
1696 */
1697 public function delete_move($newparentid, $showfeedback = false) {
1698 global $CFG, $DB, $OUTPUT;
f326c5b4 1699
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1700 require_once($CFG->libdir.'/gradelib.php');
1701 require_once($CFG->libdir.'/questionlib.php');
1702 require_once($CFG->dirroot.'/cohort/lib.php');
1703
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1704 // Get all objects and lists because later the caches will be reset so.
1705 // We don't need to make extra queries.
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1706 $newparentcat = self::get($newparentid, MUST_EXIST, true);
1707 $catname = $this->get_formatted_name();
1708 $children = $this->get_children();
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1709 $params = array('category' => $this->id);
1710 $coursesids = $DB->get_fieldset_select('course', 'id', 'category = :category ORDER BY sortorder ASC', $params);
1711 $context = $this->get_context();
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1712
1713 if ($children) {
1714 foreach ($children as $childcat) {
15d50fff 1715 $childcat->change_parent_raw($newparentcat);
b33389d2 1716 // Log action.
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1717 $event = \core\event\course_category_updated::create(array(
1718 'objectid' => $childcat->id,
1719 'context' => $childcat->get_context()
1720 ));
1721 $event->set_legacy_logdata(array(SITEID, 'category', 'move', 'editcategory.php?id=' . $childcat->id,
1722 $childcat->id));
1723 $event->trigger();
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1724 }
1725 fix_course_sortorder();
1726 }
1727
1728 if ($coursesids) {
1729 if (!move_courses($coursesids, $newparentid)) {
1730 if ($showfeedback) {
1731 echo $OUTPUT->notification("Error moving courses");
1732 }
1733 return false;
1734 }
1735 if ($showfeedback) {
1736 echo $OUTPUT->notification(get_string('coursesmovedout', '', $catname), 'notifysuccess');
1737 }
1738 }
1739
5dc361e1 1740 // Move or delete cohorts in this context.
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1741 cohort_delete_category($this);
1742
5dc361e1 1743 // Now delete anything that may depend on course category context.
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1744 grade_course_category_delete($this->id, $newparentid, $showfeedback);
1745 if (!question_delete_course_category($this, $newparentcat, $showfeedback)) {
1746 if ($showfeedback) {
1747 echo $OUTPUT->notification(get_string('errordeletingquestionsfromcategory', 'question', $catname), 'notifysuccess');
1748 }
1749 return false;
1750 }
1751
5dc361e1 1752 // Finally delete the category and it's context.
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1753 $DB->delete_records('course_categories', array('id' => $this->id));
1754 $context->delete();
b33389d2 1755
f326c5b4 1756 // Trigger a course category deleted event.
5dc361e1 1757 /* @var \core\event\course_category_deleted $event */
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1758 $event = \core\event\course_category_deleted::create(array(
1759 'objectid' => $this->id,
1760 'context' => $context,
1761 'other' => array('name' => $this->name)
1762 ));
24c32bdf 1763 $event->set_coursecat($this);
f326c5b4 1764 $event->trigger();
b33389d2 1765
eabbfa82 1766 cache_helper::purge_by_event('changesincoursecat');
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1767
1768 if ($showfeedback) {
1769 echo $OUTPUT->notification(get_string('coursecategorydeleted', '', $catname), 'notifysuccess');
1770 }
1771
1772 // If we deleted $CFG->defaultrequestcategory, make it point somewhere else.
1773 if ($this->id == $CFG->defaultrequestcategory) {
1774 set_config('defaultrequestcategory', $DB->get_field('course_categories', 'MIN(id)', array('parent' => 0)));
1775 }
1776 return true;
1777 }
1778
1779 /**
1780 * Checks if user can move current category to the new parent
1781 *
1782 * This checks if new parent category exists, user has manage cap there
1783 * and new parent is not a child of this category
1784 *
1785 * @param int|stdClass|coursecat $newparentcat
1786 * @return bool
1787 */
1788 public function can_change_parent($newparentcat) {
5dc361e1 1789 if (!has_capability('moodle/category:manage', $this->get_context())) {
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1790 return false;
1791 }
1792 if (is_object($newparentcat)) {
1793 $newparentcat = self::get($newparentcat->id, IGNORE_MISSING);
1794 } else {
1795 $newparentcat = self::get((int)$newparentcat, IGNORE_MISSING);
1796 }
1797 if (!$newparentcat) {
1798 return false;
1799 }
15d50fff 1800 if ($newparentcat->id == $this->id || in_array($this->id, $newparentcat->get_parents())) {
5dc361e1 1801 // Can not move to itself or it's own child.
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1802 return false;
1803 }
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1804 if ($newparentcat->id) {
1805 return has_capability('moodle/category:manage', context_coursecat::instance($newparentcat->id));
1806 } else {
1807 return has_capability('moodle/category:manage', context_system::instance());
1808 }
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1809 }
1810
1811 /**
1812 * Moves the category under another parent category. All associated contexts are moved as well
1813 *
1814 * This is protected function, use change_parent() or update() from outside of this class
1815 *
1816 * @see coursecat::change_parent()
1817 * @see coursecat::update()
1818 *
1819 * @param coursecat $newparentcat
484c4c6c 1820 * @throws moodle_exception
b33389d2 1821 */
484c4c6c 1822 protected function change_parent_raw(coursecat $newparentcat) {
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1823 global $DB;
1824
5dc361e1 1825 $context = $this->get_context();
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1826
1827 $hidecat = false;
1828 if (empty($newparentcat->id)) {
1829 $DB->set_field('course_categories', 'parent', 0, array('id' => $this->id));
1830 $newparent = context_system::instance();
1831 } else {
15d50fff 1832 if ($newparentcat->id == $this->id || in_array($this->id, $newparentcat->get_parents())) {
5dc361e1 1833 // Can not move to itself or it's own child.
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1834 throw new moodle_exception('cannotmovecategory');
1835 }
1836 $DB->set_field('course_categories', 'parent', $newparentcat->id, array('id' => $this->id));
1837 $newparent = context_coursecat::instance($newparentcat->id);
1838
1839 if (!$newparentcat->visible and $this->visible) {
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1840 // Better hide category when moving into hidden category, teachers may unhide afterwards and the hidden children
1841 // will be restored properly.
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1842 $hidecat = true;
1843 }
1844 }
1845 $this->parent = $newparentcat->id;
1846
9c6cfc08 1847 $context->update_moved($newparent);
b33389d2 1848
5dc361e1 1849 // Now make it last in new category.
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1850 $DB->set_field('course_categories', 'sortorder', MAX_COURSES_IN_CATEGORY*MAX_COURSE_CATEGORIES, array('id' => $this->id));
1851
1852 if ($hidecat) {
1853 fix_course_sortorder();
1854 $this->restore();
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SH
1855 // Hide object but store 1 in visibleold, because when parent category visibility changes this category must
1856 // become visible again.
15d50fff 1857 $this->hide_raw(1);
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1858 }
1859 }
1860
1861 /**
1862 * Efficiently moves a category - NOTE that this can have
1863 * a huge impact access-control-wise...
1864 *
1865 * Note that this function does not check capabilities.
1866 *
1867 * Example of usage:
1868 * $coursecat = coursecat::get($categoryid);
1869 * if ($coursecat->can_change_parent($newparentcatid)) {
1870 * $coursecat->change_parent($newparentcatid);
1871 * }
1872 *
1873 * This function does not update field course_categories.timemodified
1874 * If you want to update timemodified, use
1875 * $coursecat->update(array('parent' => $newparentcat));
1876 *
1877 * @param int|stdClass|coursecat $newparentcat
1878 */
1879 public function change_parent($newparentcat) {
1880 // Make sure parent category exists but do not check capabilities here that it is visible to current user.
1881 if (is_object($newparentcat)) {
1882 $newparentcat = self::get($newparentcat->id, MUST_EXIST, true);
1883 } else {
1884 $newparentcat = self::get((int)$newparentcat, MUST_EXIST, true);
1885 }
1886 if ($newparentcat->id != $this->parent) {
15d50fff 1887 $this->change_parent_raw($newparentcat);
b33389d2 1888 fix_course_sortorder();
eabbfa82 1889 cache_helper::purge_by_event('changesincoursecat');
b33389d2 1890 $this->restore();
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1891
1892 $event = \core\event\course_category_updated::create(array(
1893 'objectid' => $this->id,
1894 'context' => $this->get_context()
1895 ));
1896 $event->set_legacy_logdata(array(SITEID, 'category', 'move', 'editcategory.php?id=' . $this->id, $this->id));
1897 $event->trigger();
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1898 }
1899 }
1900
1901 /**
1902 * Hide course category and child course and subcategories
1903 *
1904 * If this category has changed the parent and is moved under hidden
1905 * category we will want to store it's current visibility state in
1906 * the field 'visibleold'. If admin clicked 'hide' for this particular
1907 * category, the field 'visibleold' should become 0.
1908 *
1909 * All subcategories and courses will have their current visibility in the field visibleold
1910 *
1911 * This is protected function, use hide() or update() from outside of this class
1912 *
1913 * @see coursecat::hide()
1914 * @see coursecat::update()
1915 *
1916 * @param int $visibleold value to set in field $visibleold for this category
1917 * @return bool whether changes have been made and caches need to be purged afterwards
1918 */
15d50fff 1919 protected function hide_raw($visibleold = 0) {
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1920 global $DB;
1921 $changes = false;
1922
5dc361e1 1923 // Note that field 'visibleold' is not cached so we must retrieve it from DB if it is missing.
15d50fff 1924 if ($this->id && $this->__get('visibleold') != $visibleold) {
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1925 $this->visibleold = $visibleold;
1926 $DB->set_field('course_categories', 'visibleold', $visibleold, array('id' => $this->id));
1927 $changes = true;
1928 }
1929 if (!$this->visible || !$this->id) {
5dc361e1 1930 // Already hidden or can not be hidden.
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1931 return $changes;
1932 }
1933
1934 $this->visible = 0;
1935 $DB->set_field('course_categories', 'visible', 0, array('id'=>$this->id));
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SH
1936 // Store visible flag so that we can return to it if we immediately unhide.
1937 $DB->execute("UPDATE {course} SET visibleold = visible WHERE category = ?", array($this->id));
b33389d2 1938 $DB->set_field('course', 'visible', 0, array('category' => $this->id));
5dc361e1 1939 // Get all child categories and hide too.
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1940 if ($subcats = $DB->get_records_select('course_categories', "path LIKE ?", array("$this->path/%"), 'id, visible')) {
1941 foreach ($subcats as $cat) {
1942 $DB->set_field('course_categories', 'visibleold', $cat->visible, array('id' => $cat->id));
1943 $DB->set_field('course_categories', 'visible', 0, array('id' => $cat->id));
1944 $DB->execute("UPDATE {course} SET visibleold = visible WHERE category = ?", array($cat->id));
1945 $DB->set_field('course', 'visible', 0, array('category' => $cat->id));
1946 }
1947 }
1948 return true;
1949 }
1950
1951 /**
1952 * Hide course category and child course and subcategories
1953 *
1954 * Note that there is no capability check inside this function
1955 *
1956 * This function does not update field course_categories.timemodified
1957 * If you want to update timemodified, use
1958 * $coursecat->update(array('visible' => 0));
1959 */
1960 public function hide() {
15d50fff 1961 if ($this->hide_raw(0)) {
eabbfa82 1962 cache_helper::purge_by_event('changesincoursecat');
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MN
1963
1964 $event = \core\event\course_category_updated::create(array(
1965 'objectid' => $this->id,
1966 'context' => $this->get_context()
1967 ));
1968 $event->set_legacy_logdata(array(SITEID, 'category', 'hide', 'editcategory.php?id=' . $this->id, $this->id));
1969 $event->trigger();
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1970 }
1971 }
1972
1973 /**
1974 * Show course category and restores visibility for child course and subcategories
1975 *
1976 * Note that there is no capability check inside this function
1977 *
1978 * This is protected function, use show() or update() from outside of this class
1979 *
1980 * @see coursecat::show()
1981 * @see coursecat::update()
1982 *
1983 * @return bool whether changes have been made and caches need to be purged afterwards
1984 */
15d50fff 1985 protected function show_raw() {
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MG
1986 global $DB;
1987
1988 if ($this->visible) {
5dc361e1 1989 // Already visible.
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MG
1990 return false;
1991 }
1992
1993 $this->visible = 1;
1994 $this->visibleold = 1;
1995 $DB->set_field('course_categories', 'visible', 1, array('id' => $this->id));
1996 $DB->set_field('course_categories', 'visibleold', 1, array('id' => $this->id));
1997 $DB->execute("UPDATE {course} SET visible = visibleold WHERE category = ?", array($this->id));
5dc361e1 1998 // Get all child categories and unhide too.
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MG
1999 if ($subcats = $DB->get_records_select('course_categories', "path LIKE ?", array("$this->path/%"), 'id, visibleold')) {
2000 foreach ($subcats as $cat) {
2001 if ($cat->visibleold) {
2002 $DB->set_field('course_categories', 'visible', 1, array('id' => $cat->id));
2003 }
2004 $DB->execute("UPDATE {course} SET visible = visibleold WHERE category = ?", array($cat->id));
2005 }
2006 }
2007 return true;
2008 }
2009
2010 /**
2011 * Show course category and restores visibility for child course and subcategories
2012 *
2013 * Note that there is no capability check inside this function
2014 *
2015 * This function does not update field course_categories.timemodified
2016 * If you want to update timemodified, use
2017 * $coursecat->update(array('visible' => 1));
2018 */
2019 public function show() {
15d50fff 2020 if ($this->show_raw()) {
eabbfa82 2021 cache_helper::purge_by_event('changesincoursecat');
001f0954
MN
2022
2023 $event = \core\event\course_category_updated::create(array(
2024 'objectid' => $this->id,
2025 'context' => $this->get_context()
2026 ));
2027 $event->set_legacy_logdata(array(SITEID, 'category', 'show', 'editcategory.php?id=' . $this->id, $this->id));
2028 $event->trigger();
b33389d2
MG
2029 }
2030 }
2031
2032 /**
2033 * Returns name of the category formatted as a string
2034 *
2035 * @param array $options formatting options other than context
2036 * @return string
2037 */
2038 public function get_formatted_name($options = array()) {
2039 if ($this->id) {
5dc361e1 2040 $context = $this->get_context();
b33389d2
MG
2041 return format_string($this->name, true, array('context' => $context) + $options);
2042 } else {
3b732cd6 2043 return get_string('top');
b33389d2
MG
2044 }
2045 }
2046
2047 /**
15d50fff 2048 * Returns ids of all parents of the category. Last element in the return array is the direct parent
b33389d2
MG
2049 *
2050 * For example, if you have a tree of categories like:
2051 * Miscellaneous (id = 1)
2052 * Subcategory (id = 2)
2053 * Sub-subcategory (id = 4)
2054 * Other category (id = 3)
2055 *
15d50fff
MG
2056 * coursecat::get(1)->get_parents() == array()
2057 * coursecat::get(2)->get_parents() == array(1)
2058 * coursecat::get(4)->get_parents() == array(1, 2);
b33389d2
MG
2059 *
2060 * Note that this method does not check if all parents are accessible by current user
2061 *
15d50fff 2062 * @return array of category ids
b33389d2 2063 */
15d50fff
MG
2064 public function get_parents() {
2065 $parents = preg_split('|/|', $this->path, 0, PREG_SPLIT_NO_EMPTY);
2066 array_pop($parents);
2067 return $parents;
b33389d2
MG
2068 }
2069
2070 /**
9178bbbc 2071 * This function returns a nice list representing category tree
b33389d2
MG
2072 * for display or to use in a form <select> element
2073 *
9178bbbc
MG
2074 * List is cached for 10 minutes
2075 *
b33389d2
MG
2076 * For example, if you have a tree of categories like:
2077 * Miscellaneous (id = 1)
2078 * Subcategory (id = 2)
2079 * Sub-subcategory (id = 4)
2080 * Other category (id = 3)
2081 * Then after calling this function you will have
2082 * array(1 => 'Miscellaneous',
2083 * 2 => 'Miscellaneous / Subcategory',
2084 * 4 => 'Miscellaneous / Subcategory / Sub-subcategory',
2085 * 3 => 'Other category');
2086 *
2087 * If you specify $requiredcapability, then only categories where the current
2088 * user has that capability will be added to $list.
2089 * If you only have $requiredcapability in a child category, not the parent,
2090 * then the child catgegory will still be included.
2091 *
2092 * If you specify the option $excludeid, then that category, and all its children,
2093 * are omitted from the tree. This is useful when you are doing something like
2094 * moving categories, where you do not want to allow people to move a category
2095 * to be the child of itself.
2096 *
2097 * See also {@link make_categories_options()}
2098 *
2099 * @param string/array $requiredcapability if given, only categories where the current
2100 * user has this capability will be returned. Can also be an array of capabilities,
2101 * in which case they are all required.
2102 * @param integer $excludeid Exclude this category and its children from the lists built.
2103 * @param string $separator string to use as a separator between parent and child category. Default ' / '
2104 * @return array of strings
2105 */
2106 public static function make_categories_list($requiredcapability = '', $excludeid = 0, $separator = ' / ') {
9178bbbc
MG
2107 global $DB;
2108 $coursecatcache = cache::make('core', 'coursecat');
b33389d2 2109
5dc361e1
SH
2110 // Check if we cached the complete list of user-accessible category names ($baselist) or list of ids
2111 // with requried cap ($thislist).
000f1488
HS
2112 $currentlang = current_language();
2113 $basecachekey = $currentlang . '_catlist';
9178bbbc 2114 $baselist = $coursecatcache->get($basecachekey);
9178bbbc 2115 $thislist = false;
5dc361e1 2116 $thiscachekey = null;
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MG
2117 if (!empty($requiredcapability)) {
2118 $requiredcapability = (array)$requiredcapability;
2119 $thiscachekey = 'catlist:'. serialize($requiredcapability);
2120 if ($baselist !== false && ($thislist = $coursecatcache->get($thiscachekey)) !== false) {
2121 $thislist = preg_split('|,|', $thislist, -1, PREG_SPLIT_NO_EMPTY);
b33389d2 2122 }
9178bbbc
MG
2123 } else if ($baselist !== false) {
2124 $thislist = array_keys($baselist);
2125 }
2126
2127 if ($baselist === false) {
2128 // We don't have $baselist cached, retrieve it. Retrieve $thislist again in any case.
2129 $ctxselect = context_helper::get_preload_record_columns_sql('ctx');
2130 $sql = "SELECT cc.id, cc.sortorder, cc.name, cc.visible, cc.parent, cc.path, $ctxselect
2131 FROM {course_categories} cc
2132 JOIN {context} ctx ON cc.id = ctx.instanceid AND ctx.contextlevel = :contextcoursecat
2133 ORDER BY cc.sortorder";
2134 $rs = $DB->get_recordset_sql($sql, array('contextcoursecat' => CONTEXT_COURSECAT));
2135 $baselist = array();
2136 $thislist = array();
2137 foreach ($rs as $record) {
2138 // If the category's parent is not visible to the user, it is not visible as well.
2139 if (!$record->parent || isset($baselist[$record->parent])) {
e4008e9d 2140 context_helper::preload_from_record($record);
9178bbbc
MG
2141 $context = context_coursecat::instance($record->id);
2142 if (!$record->visible && !has_capability('moodle/category:viewhiddencategories', $context)) {
5dc361e1 2143 // No cap to view category, added to neither $baselist nor $thislist.
9178bbbc
MG
2144 continue;
2145 }
2146 $baselist[$record->id] = array(
2147 'name' => format_string($record->name, true, array('context' => $context)),
2148 'path' => $record->path
2149 );
2150 if (!empty($requiredcapability) && !has_all_capabilities($requiredcapability, $context)) {
2151 // No required capability, added to $baselist but not to $thislist.
2152 continue;
2153 }
2154 $thislist[] = $record->id;
2155 }
2156 }
2157 $rs->close();
2158 $coursecatcache->set($basecachekey, $baselist);
2159 if (!empty($requiredcapability)) {
2160 $coursecatcache->set($thiscachekey, join(',', $thislist));
b33389d2 2161 }
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MG
2162 } else if ($thislist === false) {
2163 // We have $baselist cached but not $thislist. Simplier query is used to retrieve.
2164 $ctxselect = context_helper::get_preload_record_columns_sql('ctx');
deabf12e 2165 $sql = "SELECT ctx.instanceid AS id, $ctxselect
9178bbbc
MG
2166 FROM {context} ctx WHERE ctx.contextlevel = :contextcoursecat";
2167 $contexts = $DB->get_records_sql($sql, array('contextcoursecat' => CONTEXT_COURSECAT));
2168 $thislist = array();
2169 foreach (array_keys($baselist) as $id) {
2170 context_helper::preload_from_record($contexts[$id]);
2171 if (has_all_capabilities($requiredcapability, context_coursecat::instance($id))) {
2172 $thislist[] = $id;
2173 }
2174 }
2175 $coursecatcache->set($thiscachekey, join(',', $thislist));
b33389d2
MG
2176 }
2177
9178bbbc
MG
2178 // Now build the array of strings to return, mind $separator and $excludeid.
2179 $names = array();
2180 foreach ($thislist as $id) {
2181 $path = preg_split('|/|', $baselist[$id]['path'], -1, PREG_SPLIT_NO_EMPTY);
2182 if (!$excludeid || !in_array($excludeid, $path)) {
2183 $namechunks = array();
2184 foreach ($path as $parentid) {
2185 $namechunks[] = $baselist[$parentid]['name'];
2186 }
2187 $names[$id] = join($separator, $namechunks);
2188 }
b33389d2 2189 }
9178bbbc 2190 return $names;
b33389d2
MG
2191 }
2192
b33389d2
MG
2193 /**
2194 * Prepares the object for caching. Works like the __sleep method.
2195 *
9c6cfc08
MG
2196 * implementing method from interface cacheable_object
2197 *
b33389d2
MG
2198 * @return array ready to be cached
2199 */
2200 public function prepare_to_cache() {
2201 $a = array();
2202 foreach (self::$coursecatfields as $property => $cachedirectives) {
2203 if ($cachedirectives !== null) {
2204 list($shortname, $defaultvalue) = $cachedirectives;
2205 if ($this->$property !== $defaultvalue) {
2206 $a[$shortname] = $this->$property;
2207 }
2208 }
2209 }
5dc361e1 2210 $context = $this->get_context();
b33389d2
MG
2211 $a['xi'] = $context->id;
2212 $a['xp'] = $context->path;
2213 return $a;
2214 }
2215
2216 /**
2217 * Takes the data provided by prepare_to_cache and reinitialises an instance of the associated from it.
2218 *
9c6cfc08
MG
2219 * implementing method from interface cacheable_object
2220 *
b33389d2
MG
2221 * @param array $a
2222 * @return coursecat
2223 */
2224 public static function wake_from_cache($a) {
2225 $record = new stdClass;
2226 foreach (self::$coursecatfields as $property => $cachedirectives) {
2227 if ($cachedirectives !== null) {
2228 list($shortname, $defaultvalue) = $cachedirectives;
2229 if (array_key_exists($shortname, $a)) {
2230 $record->$property = $a[$shortname];
2231 } else {
2232 $record->$property = $defaultvalue;
2233 }
2234 }
2235 }
2236 $record->ctxid = $a['xi'];
2237 $record->ctxpath = $a['xp'];
2238 $record->ctxdepth = $record->depth + 1;
2239 $record->ctxlevel = CONTEXT_COURSECAT;
2240 $record->ctxinstance = $record->id;
2241 return new coursecat($record, true);
2242 }
5dc361e1
SH
2243
2244 /**
2245 * Returns true if the user is able to create a top level category.
2246 * @return bool
2247 */
2248 public static function can_create_top_level_category() {
2249 return has_capability('moodle/category:manage', context_system::instance());
2250 }
2251
2252 /**
2253 * Returns the category context.
2254 * @return context_coursecat
2255 */
2256 public function get_context() {
2257 if ($this->id === 0) {
2258 // This is the special top level category object.
2259 return context_system::instance();
2260 } else {
2261 return context_coursecat::instance($this->id);
2262 }
2263 }
2264
2265 /**
2266 * Returns true if the user is able to manage this category.
2267 * @return bool
2268 */
2269 public function has_manage_capability() {
2270 if ($this->hasmanagecapability === null) {
2271 $this->hasmanagecapability = has_capability('moodle/category:manage', $this->get_context());
2272 }
2273 return $this->hasmanagecapability;
2274 }
2275
2276 /**
2277 * Returns true if the user has the manage capability on the parent category.
2278 * @return bool
2279 */
2280 public function parent_has_manage_capability() {
2281 return has_capability('moodle/category:manage', get_category_or_system_context($this->parent));
2282 }
2283
2284 /**
2285 * Returns true if the current user can create subcategories of this category.
2286 * @return bool
2287 */
2288 public function can_create_subcategory() {
2289 return $this->has_manage_capability();
2290 }
2291
2292 /**
2293 * Returns true if the user can resort this categories sub categories and courses.
9d88b492 2294 * Must have manage capability and be able to see all subcategories.
5dc361e1
SH
2295 * @return bool
2296 */
67e1f268 2297 public function can_resort_subcategories() {
9d88b492 2298 return $this->has_manage_capability() && !$this->get_not_visible_children_ids();
67e1f268
SH
2299 }
2300
2301 /**
2302 * Returns true if the user can resort the courses within this category.
9d88b492 2303 * Must have manage capability and be able to see all courses.
67e1f268
SH
2304 * @return bool
2305 */
2306 public function can_resort_courses() {
9d88b492 2307 return $this->has_manage_capability() && $this->coursecount == $this->get_courses_count();
5dc361e1
SH
2308 }
2309
2310 /**
9d88b492 2311 * Returns true of the user can change the sortorder of this category (resort in the parent category)
5dc361e1
SH
2312 * @return bool
2313 */
2314 public function can_change_sortorder() {
9d88b492 2315 return $this->id && $this->get_parent_coursecat()->can_resort_subcategories();
5dc361e1
SH
2316 }
2317
2318 /**
2319 * Returns true if the current user can create a course within this category.
2320 * @return bool
2321 */
2322 public function can_create_course() {
2323 return has_capability('moodle/course:create', $this->get_context());
2324 }
2325
2326 /**
2327 * Returns true if the current user can edit this categories settings.
2328 * @return bool
2329 */
2330 public function can_edit() {
2331 return $this->has_manage_capability();
2332 }
2333
2334 /**
2335 * Returns true if the current user can review role assignments for this category.
2336 * @return bool
2337 */
2338 public function can_review_roles() {
2339 return has_capability('moodle/role:assign', $this->get_context());
2340 }
2341
2342 /**
2343 * Returns true if the current user can review permissions for this category.
2344 * @return bool
2345 */
2346 public function can_review_permissions() {
2347 return has_any_capability(array(
2348 'moodle/role:assign',
2349 'moodle/role:safeoverride',
2350 'moodle/role:override',
2351 'moodle/role:assign'
2352 ), $this->get_context());
2353 }
2354
2355 /**
2356 * Returns true if the current user can review cohorts for this category.
2357 * @return bool
2358 */
2359 public function can_review_cohorts() {
2360 return has_any_capability(array('moodle/cohort:view', 'moodle/cohort:manage'), $this->get_context());
2361 }
2362
2363 /**
2364 * Returns true if the current user can review filter settings for this category.
2365 * @return bool
2366 */
2367 public function can_review_filters() {
2368 return has_capability('moodle/filter:manage', $this->get_context()) &&
2369 count(filter_get_available_in_context($this->get_context()))>0;
2370 }
2371
2372 /**
2373 * Returns true if the current user is able to change the visbility of this category.
2374 * @return bool
2375 */
2376 public function can_change_visibility() {
2377 return $this->parent_has_manage_capability();
2378 }
2379
2380 /**
2381 * Returns true if the user can move courses out of this category.
2382 * @return bool
2383 */
2384 public function can_move_courses_out_of() {
2385 return $this->has_manage_capability();
2386 }
2387
2388 /**
2389 * Returns true if the user can move courses into this category.
2390 * @return bool
2391 */
2392 public function can_move_courses_into() {
2393 return $this->has_manage_capability();
2394 }
2395
39bd07f7
SH
2396 /**
2397 * Returns true if the user is able to restore a course into this category as a new course.
2398 * @return bool
2399 */
2400 public function can_restore_courses_into() {
2401 return has_capability('moodle/course:create', $this->get_context());
2402 }
2403
5dc361e1
SH
2404 /**
2405 * Resorts the sub categories of this category by the given field.
2406 *
9a4231e9 2407 * @param string $field One of name, idnumber or descending values of each (appended desc)
5dc361e1
SH
2408 * @param bool $cleanup If true cleanup will be done, if false you will need to do it manually later.
2409 * @return bool True on success.
2410 * @throws coding_exception
2411 */
2412 public function resort_subcategories($field, $cleanup = true) {
2413 global $DB;
9a4231e9
S
2414 $desc = false;
2415 if (substr($field, -4) === "desc") {
2416 $desc = true;
2417 $field = substr($field, 0, -4); // Remove "desc" from field name.
2418 }
5dc361e1
SH
2419 if ($field !== 'name' && $field !== 'idnumber') {
2420 throw new coding_exception('Invalid field requested');
2421 }
2422 $children = $this->get_children();
2423 core_collator::asort_objects_by_property($children, $field, core_collator::SORT_NATURAL);
9a4231e9
S
2424 if (!empty($desc)) {
2425 $children = array_reverse($children);
2426 }
5dc361e1
SH
2427 $i = 1;
2428 foreach ($children as $cat) {
2429 $i++;
2430 $DB->set_field('course_categories', 'sortorder', $i, array('id' => $cat->id));
2431 $i += $cat->coursecount;
2432 }
2433 if ($cleanup) {
2434 self::resort_categories_cleanup();
2435 }
2436 return true;
2437 }
2438
2439 /**
2440 * Cleans things up after categories have been resorted.
c7a2291f 2441 * @param bool $includecourses If set to true we know courses have been resorted as well.
5dc361e1 2442 */
c7a2291f 2443 public static function resort_categories_cleanup($includecourses = false) {
5dc361e1
SH
2444 // This should not be needed but we do it just to be safe.
2445 fix_course_sortorder();
2446 cache_helper::purge_by_event('changesincoursecat');
c7a2291f
SH
2447 if ($includecourses) {
2448 cache_helper::purge_by_event('changesincourse');
2449 }
5dc361e1
SH
2450 }
2451
2452 /**
2453 * Resort the courses within this category by the given field.
2454 *
9a4231e9 2455 * @param string $field One of fullname, shortname, idnumber or descending values of each (appended desc)
5dc361e1
SH
2456 * @param bool $cleanup
2457 * @return bool True for success.
2458 * @throws coding_exception
2459 */
2460 public function resort_courses($field, $cleanup = true) {
2461 global $DB;
9a4231e9
S
2462 $desc = false;
2463 if (substr($field, -4) === "desc") {
2464 $desc = true;
2465 $field = substr($field, 0, -4); // Remove "desc" from field name.
2466 }
2467 if ($field !== 'fullname' && $field !== 'shortname' && $field !== 'idnumber' && $field !== 'timecreated') {
5dc361e1
SH
2468 // This is ultra important as we use $field in an SQL statement below this.
2469 throw new coding_exception('Invalid field requested');
2470 }
2471 $ctxfields = context_helper::get_preload_record_columns_sql('ctx');
2472 $sql = "SELECT c.id, c.sortorder, c.{$field}, $ctxfields
2473 FROM {course} c
2474 LEFT JOIN {context} ctx ON ctx.instanceid = c.id
2475 WHERE ctx.contextlevel = :ctxlevel AND
9a4231e9 2476 c.category = :categoryid";
5dc361e1
SH
2477 $params = array(
2478 'ctxlevel' => CONTEXT_COURSE,
2479 'categoryid' => $this->id
2480 );
2481 $courses = $DB->get_records_sql($sql, $params);
2482 if (count($courses) > 0) {
2483 foreach ($courses as $courseid => $course) {
2484 context_helper::preload_from_record($course);
2485 if ($field === 'idnumber') {
2486 $course->sortby = $course->idnumber;
2487 } else {
2488 // It'll require formatting.
2489 $options = array(
2490 'context' => context_course::instance($course->id)
2491 );
2492 // We format the string first so that it appears as the user would see it.
2493 // This ensures the sorting makes sense to them. However it won't necessarily make
2494 // sense to everyone if things like multilang filters are enabled.
2495 // We then strip any tags as we don't want things such as image tags skewing the
2496 // sort results.
2497 $course->sortby = strip_tags(format_string($course->$field, true, $options));
2498 }
2499 // We set it back here rather than using references as there is a bug with using
2500 // references in a foreach before passing as an arg by reference.
2501 $courses[$courseid] = $course;
2502 }
2503 // Sort the courses.
2504 core_collator::asort_objects_by_property($courses, 'sortby', core_collator::SORT_NATURAL);
9a4231e9
S
2505 if (!empty($desc)) {
2506 $courses = array_reverse($courses);
2507 }
5dc361e1
SH
2508 $i = 1;
2509 foreach ($courses as $course) {
2510 $DB->set_field('course', 'sortorder', $this->sortorder + $i, array('id' => $course->id));
2511 $i++;
2512 }
2513 if ($cleanup) {
2514 // This should not be needed but we do it just to be safe.
2515 fix_course_sortorder();
2516 cache_helper::purge_by_event('changesincourse');
2517 }
2518 }
2519 return true;
2520 }
2521
2522 /**
5aff38e4 2523 * Changes the sort order of this categories parent shifting this category up or down one.
5dc361e1
SH
2524 *
2525 * @global \moodle_database $DB
5aff38e4 2526 * @param bool $up If set to true the category is shifted up one spot, else its moved down.
5dc361e1
SH
2527 * @return bool True on success, false otherwise.
2528 */
5aff38e4 2529 public function change_sortorder_by_one($up) {
5dc361e1
SH
2530 global $DB;
2531 $params = array($this->sortorder, $this->parent);
2532 if ($up) {
2533 $select = 'sortorder < ? AND parent = ?';
2534 $sort = 'sortorder DESC';
2535 } else {
2536 $select = 'sortorder > ? AND parent = ?';
2537 $sort = 'sortorder ASC';
2538 }
2539 fix_course_sortorder();
2540 $swapcategory = $DB->get_records_select('course_categories', $select, $params, $sort, '*', 0, 1);
2541 $swapcategory = reset($swapcategory);
2542 if ($swapcategory) {
2543 $DB->set_field('course_categories', 'sortorder', $swapcategory->sortorder, array('id' => $this->id));
2544 $DB->set_field('course_categories', 'sortorder', $this->sortorder, array('id' => $swapcategory->id));
2545 $this->sortorder = $swapcategory->sortorder;
d86c7206
MN
2546
2547 $event = \core\event\course_category_updated::create(array(
2548 'objectid' => $this->id,
2549 'context' => $this->get_context()
2550 ));
2551 $event->set_legacy_logdata(array(SITEID, 'category', 'move', 'management.php?categoryid=' . $this->id,
2552 $this->id));
2553 $event->trigger();
2554
5dc361e1
SH
2555 // Finally reorder courses.
2556 fix_course_sortorder();
2557 cache_helper::purge_by_event('changesincoursecat');
2558 return true;
2559 }
2560 return false;
2561 }
2562
2563 /**
2564 * Returns the parent coursecat object for this category.
2565 *
2566 * @return coursecat
2567 */
2568 public function get_parent_coursecat() {
484c4c6c
SH
2569 return self::get($this->parent);
2570 }
2571
2572
2573 /**
2574 * Returns true if the user is able to request a new course be created.
2575 * @return bool
2576 */
2577 public function can_request_course() {
2578 global $CFG;
2579 if (empty($CFG->enablecourserequests) || $this->id != $CFG->defaultrequestcategory) {
2580 return false;
2581 }
2582 return !$this->can_create_course() && has_capability('moodle/course:request', $this->get_context());
2583 }
2584
2585 /**
2586 * Returns true if the user can approve course requests.
2587 * @return bool
2588 */
2589 public static function can_approve_course_requests() {
2590 global $CFG, $DB;
2591 if (empty($CFG->enablecourserequests)) {
2592 return false;
2593 }
2594 $context = context_system::instance();
2595 if (!has_capability('moodle/site:approvecourse', $context)) {
2596 return false;
2597 }
2598 if (!$DB->record_exists('course_request', array())) {
2599 return false;
2600 }
2601 return true;
5dc361e1 2602 }
b33389d2 2603}
93c544bd
MG
2604
2605/**
2606 * Class to store information about one course in a list of courses
2607 *
2608 * Not all information may be retrieved when object is created but
2609 * it will be retrieved on demand when appropriate property or method is
2610 * called.
2611 *
2612 * Instances of this class are usually returned by functions
2613 * {@link coursecat::search_courses()}
2614 * and
2615 * {@link coursecat::get_courses()}
2616 *
1eac2033
SH
2617 * @property-read int $id
2618 * @property-read int $category Category ID
2619 * @property-read int $sortorder
2620 * @property-read string $fullname
2621 * @property-read string $shortname
2622 * @property-read string $idnumber
85708da6
MG
2623 * @property-read string $summary Course summary. Field is present if coursecat::get_courses()
2624 * was called with option 'summary'. Otherwise will be retrieved from DB on first request
2625 * @property-read int $summaryformat Summary format. Field is present if coursecat::get_courses()
2626 * was called with option 'summary'. Otherwise will be retrieved from DB on first request
2627 * @property-read string $format Course format. Retrieved from DB on first request
2628 * @property-read int $showgrades Retrieved from DB on first request
85708da6 2629 * @property-read int $newsitems Retrieved from DB on first request
1eac2033 2630 * @property-read int $startdate
85708da6
MG
2631 * @property-read int $marker Retrieved from DB on first request
2632 * @property-read int $maxbytes Retrieved from DB on first request
2633 * @property-read int $legacyfiles Retrieved from DB on first request
2634 * @property-read int $showreports Retrieved from DB on first request
1eac2033 2635 * @property-read int $visible
85708da6
MG
2636 * @property-read int $visibleold Retrieved from DB on first request
2637 * @property-read int $groupmode Retrieved from DB on first request
2638 * @property-read int $groupmodeforce Retrieved from DB on first request
2639 * @property-read int $defaultgroupingid Retrieved from DB on first request
2640 * @property-read string $lang Retrieved from DB on first request
2641 * @property-read string $theme Retrieved from DB on first request
2642 * @property-read int $timecreated Retrieved from DB on first request
2643 * @property-read int $timemodified Retrieved from DB on first request
2644 * @property-read int $requested Retrieved from DB on first request
2645 * @property-read int $enablecompletion Retrieved from DB on first request
2646 * @property-read int $completionnotify Retrieved from DB on first request
4a3fb71c 2647 * @property-read int $cacherev
1eac2033 2648 *
93c544bd
MG
2649 * @package core
2650 * @subpackage course
2651 * @copyright 2013 Marina Glancy
2652 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
2653 */
2654class course_in_list implements IteratorAggregate {
2655
2656 /** @var stdClass record retrieved from DB, may have additional calculated property such as managers and hassummary */
2657 protected $record;
2658
2659 /** @var array array of course contacts - stores result of call to get_course_contacts() */
2660 protected $coursecontacts;
2661
484c4c6c
SH
2662 /** @var bool true if the current user can access the course, false otherwise. */
2663 protected $canaccess = null;
2664
93c544bd
MG
2665 /**
2666 * Creates an instance of the class from record
2667 *
2668 * @param stdClass $record except fields from course table it may contain
2669 * field hassummary indicating that summary field is not empty.
2670 * Also it is recommended to have context fields here ready for
2671 * context preloading
2672 */
2673 public function __construct(stdClass $record) {
db314f34 2674 context_helper::preload_from_record($record);
93c544bd
MG
2675 $this->record = new stdClass();
2676 foreach ($record as $key => $value) {
2677 $this->record->$key = $value;
2678 }
2679 }
2680
2681 /**
2682 * Indicates if the course has non-empty summary field
2683 *
2684 * @return bool
2685 */
2686 public function has_summary() {
2687 if (isset($this->record->hassummary)) {
2688 return !empty($this->record->hassummary);
2689 }
2690 if (!isset($this->record->summary)) {
5dc361e1 2691 // We need to retrieve summary.
93c544bd
MG
2692 $this->__get('summary');
2693 }
2694 return !empty($this->record->summary);
2695 }
2696
2697 /**
2698 * Indicates if the course have course contacts to display
2699 *
2700 * @return bool
2701 */
2702 public function has_course_contacts() {
2703 if (!isset($this->record->managers)) {
2704 $courses = array($this->id => &$this->record);
2705 coursecat::preload_course_contacts($courses);
2706 }
2707 return !empty($this->record->managers);
2708 }
2709
2710 /**
2711 * Returns list of course contacts (usually teachers) to display in course link
2712 *
2713 * Roles to display are set up in $CFG->coursecontact
2714 *
2715 * The result is the list of users where user id is the key and the value
2716 * is an array with elements:
2717 * - 'user' - object containing basic user information
2718 * - 'role' - object containing basic role information (id, name, shortname, coursealias)
2719 * - 'rolename' => role_get_name($role, $context, ROLENAME_ALIAS)
2720 * - 'username' => fullname($user, $canviewfullnames)
2721 *
2722 * @return array
2723 */
2724 public function get_course_contacts() {
2725 global $CFG;
2726 if (empty($CFG->coursecontact)) {
5dc361e1 2727 // No roles are configured to be displayed as course contacts.
93c544bd
MG
2728 return array();
2729 }
2730 if ($this->coursecontacts === null) {
2731 $this->coursecontacts = array();
2732 $context = context_course::instance($this->id);
2733
2734 if (!isset($this->record->managers)) {
5dc361e1 2735 // Preload course contacts from DB.
93c544bd
MG
2736 $courses = array($this->id => &$this->record);
2737 coursecat::preload_course_contacts($courses);
2738 }
2739
5dc361e1 2740 // Build return array with full roles names (for this course context) and users names.
93c544bd
MG
2741 $canviewfullnames = has_capability('moodle/site:viewfullnames', $context);
2742 foreach ($this->record->managers as $ruser) {
2743 if (isset($this->coursecontacts[$ruser->id])) {
5dc361e1 2744 // Only display a user once with the highest sortorder role.
93c544bd
MG
2745 continue;
2746 }
2747 $user = new stdClass();
5b1944bb 2748 $user = username_load_fields_from_object($user, $ruser, null, array('id', 'username'));
93c544bd
MG
2749 $role = new stdClass();
2750 $role->id = $ruser->roleid;
2751 $role->name = $ruser->rolename;
2752 $role->shortname = $ruser->roleshortname;
2753 $role->coursealias = $ruser->rolecoursealias;
2754
2755 $this->coursecontacts[$user->id] = array(
2756 'user' => $user,
2757 'role' => $role,
2758 'rolename' => role_get_name($role, $context, ROLENAME_ALIAS),
2759 'username' => fullname($user, $canviewfullnames)
2760 );
2761 }
2762 }
2763 return $this->coursecontacts;
2764 }
2765
d1f8c1bd
MG
2766 /**
2767 * Checks if course has any associated overview files
2768 *
2769 * @return bool
2770 */
2771 public function has_course_overviewfiles() {
2772 global $CFG;
2773 if (empty($CFG->courseoverviewfileslimit)) {
961403c4 2774 return false;
d1f8c1bd 2775 }
d1f8c1bd
MG
2776 $fs = get_file_storage();
2777 $context = context_course::instance($this->id);
961403c4 2778 return !$fs->is_area_empty($context->id, 'course', 'overviewfiles');
d1f8c1bd
MG
2779 }
2780
2781 /**
2782 * Returns all course overview files
2783 *
2784 * @return array array of stored_file objects
2785 */
2786 public function get_course_overviewfiles() {
2787 global $CFG;
2788 if (empty($CFG->courseoverviewfileslimit)) {
2789 return array();
2790 }
2791 require_once($CFG->libdir. '/filestorage/file_storage.php');
473d5f74 2792 require_once($CFG->dirroot. '/course/lib.php');
d1f8c1bd
MG
2793 $fs = get_file_storage();
2794 $context = context_course::instance($this->id);
2795 $files = $fs->get_area_files($context->id, 'course', 'overviewfiles', false, 'filename', false);
2796 if (count($files)) {
2797 $overviewfilesoptions = course_overviewfiles_options($this->id);
2798 $acceptedtypes = $overviewfilesoptions['accepted_types'];
2799 if ($acceptedtypes !== '*') {
5dc361e1 2800 // Filter only files with allowed extensions.
d1f8c1bd 2801 require_once($CFG->libdir. '/filelib.php');
15f89e28
SH
2802 foreach ($files as $key => $file) {
2803 if (!file_extension_in_typegroup($file->get_filename(), $acceptedtypes)) {
2804 unset($files[$key]);
2805 }
2806 }
d1f8c1bd
MG
2807 }
2808 if (count($files) > $CFG->courseoverviewfileslimit) {
5dc361e1 2809 // Return no more than $CFG->courseoverviewfileslimit files.
d1f8c1bd
MG
2810 $files = array_slice($files, 0, $CFG->courseoverviewfileslimit, true);
2811 }
2812 }
2813 return $files;
2814 }
2815
5dc361e1
SH
2816 /**
2817 * Magic method to check if property is set
2818 *
2819 * @param string $name
2820 * @return bool
2821 */
93c544bd
MG
2822 public function __isset($name) {
2823 return isset($this->record->$name);
2824 }
2825
2826 /**
2827 * Magic method to get a course property
2828 *
5dc361e1 2829 * Returns any field from table course (retrieves it from DB if it was not retrieved before)
93c544bd
MG
2830 *
2831 * @param string $name
2832 * @return mixed
2833 */
2834 public function __get($name) {
2835 global $DB;
2836 if (property_exists($this->record, $name)) {
2837 return $this->record->$name;
2838 } else if ($name === 'summary' || $name === 'summaryformat') {
5dc361e1 2839 // Retrieve fields summary and summaryformat together because they are most likely to be used together.
93c544bd
MG
2840 $record = $DB->get_record('course', array('id' => $this->record->id), 'summary, summaryformat', MUST_EXIST);
2841 $this->record->summary = $record->summary;
2842 $this->record->summaryformat = $record->summaryformat;
2843 return $this->record->$name;
2844 } else if (array_key_exists($name, $DB->get_columns('course'))) {
5dc361e1 2845 // Another field from table 'course' that was not retrieved.
93c544bd
MG
2846 $this->record->$name = $DB->get_field('course', $name, array('id' => $this->record->id), MUST_EXIST);
2847 return $this->record->$name;
2848 }
2849 debugging('Invalid course property accessed! '.$name);
2850 return null;
2851 }
2852
2853 /**
5dc361e1
SH
2854 * All properties are read only, sorry.
2855 *
93c544bd
MG
2856 * @param string $name
2857 */
2858 public function __unset($name) {
2859 debugging('Can not unset '.get_class($this).' instance properties!');
2860 }
2861
2862 /**
2863 * Magic setter method, we do not want anybody to modify properties from the outside
5dc361e1 2864 *
93c544bd
MG
2865 * @param string $name
2866 * @param mixed $value
2867 */
2868 public function __set($name, $value) {
2869 debugging('Can not change '.get_class($this).' instance properties!');
2870 }
2871
93c544bd
MG
2872 /**
2873 * Create an iterator because magic vars can't be seen by 'foreach'.
2874 * Exclude context fields
5dc361e1
SH
2875 *
2876 * Implementing method from interface IteratorAggregate
2877 *
2878 * @return ArrayIterator
93c544bd
MG
2879 */
2880 public function getIterator() {
2881 $ret = array('id' => $this->record->id);
2882 foreach ($this->record as $property => $value) {
2883 $ret[$property] = $value;
2884 }
2885 return new ArrayIterator($ret);
2886 }
5dc361e1
SH
2887
2888 /**
2889 * Returns the name of this course as it should be displayed within a list.
2890 * @return string
2891 */
2892 public function get_formatted_name() {
2893 return format_string(get_course_display_name_for_list($this), true, $this->get_context());
2894 }
2895
2896 /**
2897 * Returns the formatted fullname for this course.
2898 * @return string
2899 */
2900 public function get_formatted_fullname() {
2901 return format_string($this->__get('fullname'), true, $this->get_context());
2902 }
2903
2904 /**
2905 * Returns the formatted shortname for this course.
2906 * @return string
2907 */
2908 public function get_formatted_shortname() {
2909 return format_string($this->__get('shortname'), true, $this->get_context());
2910 }
2911
2912 /**
2913 * Returns true if the current user can access this course.
2914 * @return bool
2915 */
2916 public function can_access() {
484c4c6c
SH
2917 if ($this->canaccess === null) {
2918 $this->canaccess = can_access_course($this->record);
2919 }
2920 return $this->canaccess;
5dc361e1
SH
2921 }
2922
2923 /**
2924 * Returns true if the user can edit this courses settings.
484c4c6c
SH
2925 *
2926 * Note: this function does not check that the current user can access the course.
2927 * To do that please call require_login with the course, or if not possible call {@see course_in_list::can_access()}
2928 *
5dc361e1
SH
2929 * @return bool
2930 */
2931 public function can_edit() {
2932 return has_capability('moodle/course:update', $this->get_context());
2933 }
2934
2935 /**
2936 * Returns true if the user can change the visibility of this course.
484c4c6c
SH
2937 *
2938 * Note: this function does not check that the current user can access the course.
2939 * To do that please call require_login with the course, or if not possible call {@see course_in_list::can_access()}
2940 *
5dc361e1
SH
2941 * @return bool
2942 */
2943 public function can_change_visibility() {
2944 // You must be able to both hide a course and view the hidden course.
2945 return has_all_capabilities(array('moodle/course:visibility', 'moodle/course:viewhiddencourses'), $this->get_context());
2946 }
2947
2948 /**
2949 * Returns the context for this course.
2950 * @return context_course
2951 */
2952 public function get_context() {
2953 return context_course::instance($this->__get('id'));
2954 }
2955
484c4c6c
SH
2956 /**
2957 * Returns true if this course is visible to the current user.
2958 * @return bool
2959 */
2960 public function is_uservisible() {
2961 return $this->visible || has_capability('moodle/course:viewhiddencourses', $this->get_context());
2962 }
2963
5dc361e1
SH
2964 /**
2965 * Returns true if the current user can review enrolments for this course.
484c4c6c
SH
2966 *
2967 * Note: this function does not check that the current user can access the course.
2968 * To do that please call require_login with the course, or if not possible call {@see course_in_list::can_access()}
2969 *
5dc361e1
SH
2970 * @return bool
2971 */
2972 public function can_review_enrolments() {
2973 return has_capability('moodle/course:enrolreview', $this->get_context());
2974 }
2975
2976 /**
2977 * Returns true if the current user can delete this course.
484c4c6c
SH
2978 *
2979 * Note: this function does not check that the current user can access the course.
2980 * To do that please call require_login with the course, or if not possible call {@see course_in_list::can_access()}
2981 *
5dc361e1
SH
2982 * @return bool
2983 */
2984 public function can_delete() {
2985 return can_delete_course($this->id);
2986 }
2987
2988 /**
2989 * Returns true if the current user can backup this course.
484c4c6c
SH
2990 *
2991 * Note: this function does not check that the current user can access the course.
2992 * To do that please call require_login with the course, or if not possible call {@see course_in_list::can_access()}
2993 *
5dc361e1
SH
2994 * @return bool
2995 */
2996 public function can_backup() {
2997 return has_capability('moodle/backup:backupcourse', $this->get_context());
2998 }
2999
3000 /**
3001 * Returns true if the current user can restore this course.
484c4c6c
SH
3002 *
3003 * Note: this function does not check that the current user can access the course.
3004 * To do that please call require_login with the course, or if not possible call {@see course_in_list::can_access()}
3005 *
5dc361e1
SH
3006 * @return bool
3007 */
3008 public function can_restore() {
3009 return has_capability('moodle/restore:restorecourse', $this->get_context());
3010 }
93c544bd 3011}
15f89e28
SH
3012
3013/**
3014 * An array of records that is sortable by many fields.
3015 *
3016 * For more info on the ArrayObject class have a look at php.net.
3017 *
3018 * @package core
3019 * @subpackage course
3020 * @copyright 2013 Sam Hemelryk
3021 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
3022 */
3023class coursecat_sortable_records extends ArrayObject {
3024
3025 /**
3026 * An array of sortable fields.
3027 * Gets set temporarily when sort is called.
3028 * @var array
3029 */
3030 protected $sortfields = array();
3031
3032 /**
3033 * Sorts this array using the given fields.
3034 *
3035 * @param array $records
3036 * @param array $fields
3037 * @return array
3038 */
3039 public static function sort(array $records, array $fields) {
3040 $records = new coursecat_sortable_records($records);
3041 $records->sortfields = $fields;
3042 $records->uasort(array($records, 'sort_by_many_fields'));
3043 return $records->getArrayCopy();
3044 }
3045
3046 /**
3047 * Sorts the two records based upon many fields.
3048 *
3049 * This method should not be called itself, please call $sort instead.
3050 * It has been marked as access private as such.
3051 *
3052 * @access private
3053 * @param stdClass $a
3054 * @param stdClass $b
3055 * @return int
3056 */
3057 public function sort_by_many_fields($a, $b) {
3058 foreach ($this->sortfields as $field => $mult) {
5dc361e1 3059 // Nulls first.
15f89e28
SH
3060 if (is_null($a->$field) && !is_null($b->$field)) {
3061 return -$mult;
3062 }
3063 if (is_null($b->$field) && !is_null($a->$field)) {
3064 return $mult;
3065 }
3066
3067 if (is_string($a->$field) || is_string($b->$field)) {
5dc361e1 3068 // String fields.
15f89e28
SH
3069 if ($cmp = strcoll($a->$field, $b->$field)) {
3070 return $mult * $cmp;
3071 }
3072 } else {
5dc361e1 3073 // Int fields.
15f89e28
SH
3074 if ($a->$field > $b->$field) {
3075 return $mult;
3076 }
3077 if ($a->$field < $b->$field) {
3078 return -$mult;
3079 }
3080 }
3081 }
3082 return 0;
3083 }
36ba8fde 3084}