question/category_class.php

   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  * A class for representing question categories.
  19  *
  20  * @package    moodlecore
  21  * @subpackage questionbank
  22  * @copyright  1999 onwards Martin Dougiamas {@link http://moodle.com}
  23  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  24  */
  25
  26
  27 defined('MOODLE_INTERNAL') || die();
  28
  29 // number of categories to display on page
  30 define('QUESTION_PAGE_LENGTH', 25);
  31
  32 require_once($CFG->libdir . '/listlib.php');
  33 require_once($CFG->dirroot . '/question/category_form.php');
  34 require_once($CFG->dirroot . '/question/move_form.php');
  35
  36
  37 /**
  38  * Class representing a list of question categories
  39  *
  40  * @copyright  1999 onwards Martin Dougiamas {@link http://moodle.com}
  41  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  42  */
  43 class question_category_list extends moodle_list {
  44     public $table = "question_categories";
  45     public $listitemclassname = 'question_category_list_item';
  46     /**
  47      * @var reference to list displayed below this one.
  48      */
  49     public $nextlist = null;
  50     /**
  51      * @var reference to list displayed above this one.
  52      */
  53     public $lastlist = null;
  54
  55     public $context = null;
  56     public $sortby = 'parent, sortorder, name';
  57
  58     public function __construct($type='ul', $attributes='', $editable = false, $pageurl=null, $page = 0, $pageparamname = 'page', $itemsperpage = 20, $context = null){
  59         parent::__construct('ul', '', $editable, $pageurl, $page, 'cpage', $itemsperpage);
  60         $this->context = $context;
  61     }
  62
  63     public function get_records() {
  64         $this->records = get_categories_for_contexts($this->context->id, $this->sortby);
  65     }
  66
  67     /**
  68      * Returns the highest category id that the $item can have as its parent.
  69      * Note: question categories cannot go higher than the TOP category.
  70      *
  71      * @param list_item $item The item which its top level parent is going to be returned.
  72      * @return int
  73      */
  74     public function get_top_level_parent_id($item) {
  75         // Put the item at the highest level it can go.
  76         $topcategory = question_get_top_category($item->item->contextid, true);
  77         return $topcategory->id;
  78     }
  79
  80     /**
  81      * process any actions.
  82      *
  83      * @param integer $left id of item to move left
  84      * @param integer $right id of item to move right
  85      * @param integer $moveup id of item to move up
  86      * @param integer $movedown id of item to move down
  87      * @return void
  88      * @throws coding_exception
  89      */
  90     public function process_actions($left, $right, $moveup, $movedown) {
  91         $category = new stdClass();
  92         if (!empty($left)) {
  93             // Moved Left (In to another category).
  94             $category->id = $left;
  95             $category->contextid = $this->context->id;
  96             $event = \core\event\question_category_moved::create_from_question_category_instance($category);
  97             $event->trigger();
  98         } else if (!empty($right)) {
  99             // Moved Right (Out of the current category).
 100             $category->id = $right;
 101             $category->contextid = $this->context->id;
 102             $event = \core\event\question_category_moved::create_from_question_category_instance($category);
 103             $event->trigger();
 104         }
 105         parent::process_actions($left, $right, $moveup, $movedown);
 106     }
 107 }
 108
 109 /**
 110  * An item in a list of question categories.
 111  *
 112  * @copyright  1999 onwards Martin Dougiamas {@link http://moodle.com}
 113  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 114  */
 115 class question_category_list_item extends list_item {
 116     public function set_icon_html($first, $last, $lastitem){
 117         global $CFG;
 118         $category = $this->item;
 119         $url = new moodle_url('/question/category.php', ($this->parentlist->pageurl->params() + array('edit'=>$category->id)));
 120         $this->icons['edit']= $this->image_icon(get_string('editthiscategory', 'question'), $url, 'edit');
 121         parent::set_icon_html($first, $last, $lastitem);
 122         $toplevel = ($this->parentlist->parentitem === null);//this is a top level item
 123         if (($this->parentlist->nextlist !== null) && $last && $toplevel && (count($this->parentlist->items)>1)){
 124             $url = new moodle_url($this->parentlist->pageurl, array('movedowncontext'=>$this->id, 'tocontext'=>$this->parentlist->nextlist->context->id, 'sesskey'=>sesskey()));
 125             $this->icons['down'] = $this->image_icon(
 126                 get_string('shareincontext', 'question', $this->parentlist->nextlist->context->get_context_name()), $url, 'down');
 127         }
 128         if (($this->parentlist->lastlist !== null) && $first && $toplevel && (count($this->parentlist->items)>1)){
 129             $url = new moodle_url($this->parentlist->pageurl, array('moveupcontext'=>$this->id, 'tocontext'=>$this->parentlist->lastlist->context->id, 'sesskey'=>sesskey()));
 130             $this->icons['up'] = $this->image_icon(
 131                 get_string('shareincontext', 'question', $this->parentlist->lastlist->context->get_context_name()), $url, 'up');
 132         }
 133     }
 134
 135     public function item_html($extraargs = array()){
 136         global $CFG, $OUTPUT;
 137         $str = $extraargs['str'];
 138         $category = $this->item;
 139
 140         $editqestions = get_string('editquestions', 'question');
 141
 142         // Each section adds html to be displayed as part of this list item.
 143         $questionbankurl = new moodle_url('/question/edit.php', $this->parentlist->pageurl->params());
 144         $questionbankurl->param('cat', $category->id . ',' . $category->contextid);
 145         $item = '';
 146         $text = format_string($category->name, true, ['context' => $this->parentlist->context]);
 147         if ($category->idnumber !== null && $category->idnumber !== '') {
 148             $text .= ' ' . html_writer::span(
 149                     html_writer::span(get_string('idnumber', 'question'), 'accesshide') .
 150                     ' ' . $category->idnumber, 'badge badge-primary');
 151         }
 152         $text .= ' (' . $category->questioncount . ')';
 153         $item .= html_writer::tag('b', html_writer::link($questionbankurl, $text,
 154                         ['title' => $editqestions]) . ' ');
 155         $item .= format_text($category->info, $category->infoformat,
 156                 array('context' => $this->parentlist->context, 'noclean' => true));
 157
 158         // Don't allow delete if this is the top category, or the last editable category in this context.
 159         if ($category->parent && !question_is_only_child_of_top_category_in_context($category->id)) {
 160             $deleteurl = new moodle_url($this->parentlist->pageurl, array('delete' => $this->id, 'sesskey' => sesskey()));
 161             $item .= html_writer::link($deleteurl,
 162                     $OUTPUT->pix_icon('t/delete', $str->delete),
 163                     array('title' => $str->delete));
 164         }
 165
 166         return $item;
 167     }
 168 }
 169
 170
 171 /**
 172  * Class for performing operations on question categories.
 173  *
 174  * @copyright  1999 onwards Martin Dougiamas {@link http://moodle.com}
 175  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 176  */
 177 class question_category_object {
 178
 179     /**
 180      * @var array common language strings.
 181      */
 182     public $str;
 183
 184     /**
 185      * @var array nested lists to display categories.
 186      */
 187     public $editlists = array();
 188     public $tab;
 189     public $tabsize = 3;
 190
 191     /**
 192      * @var moodle_url Object representing url for this page
 193      */
 194     public $pageurl;
 195
 196     /**
 197      * @var question_category_edit_form Object representing form for adding / editing categories.
 198      */
 199     public $catform;
 200
 201     /**
 202      * Constructor.
 203      *
 204      * @param int $page page number
 205      * @param moodle_url $pageurl base URL of the display categories page. Used for redirects.
 206      * @param context[] $contexts contexts where the current user can edit categories.
 207      * @param int $currentcat id of the category to be edited. 0 if none.
 208      * @param int|null $defaultcategory id of the current category. null if none.
 209      * @param int $todelete id of the category to delete. 0 if none.
 210      * @param context[] $addcontexts contexts where the current user can add questions.
 211      */
 212     public function __construct($page, $pageurl, $contexts, $currentcat, $defaultcategory, $todelete, $addcontexts) {
 213
 214         $this->tab = str_repeat('&nbsp;', $this->tabsize);
 215
 216         $this->str = new stdClass();
 217         $this->str->course         = get_string('course');
 218         $this->str->category       = get_string('category', 'question');
 219         $this->str->categoryinfo   = get_string('categoryinfo', 'question');
 220         $this->str->questions      = get_string('questions', 'question');
 221         $this->str->add            = get_string('add');
 222         $this->str->delete         = get_string('delete');
 223         $this->str->moveup         = get_string('moveup');
 224         $this->str->movedown       = get_string('movedown');
 225         $this->str->edit           = get_string('editthiscategory', 'question');
 226         $this->str->hide           = get_string('hide');
 227         $this->str->order          = get_string('order');
 228         $this->str->parent         = get_string('parent', 'question');
 229         $this->str->add            = get_string('add');
 230         $this->str->action         = get_string('action');
 231         $this->str->top            = get_string('top');
 232         $this->str->addcategory    = get_string('addcategory', 'question');
 233         $this->str->editcategory   = get_string('editcategory', 'question');
 234         $this->str->cancel         = get_string('cancel');
 235         $this->str->editcategories = get_string('editcategories', 'question');
 236         $this->str->page           = get_string('page');
 237
 238         $this->pageurl = $pageurl;
 239
 240         $this->initialize($page, $contexts, $currentcat, $defaultcategory, $todelete, $addcontexts);
 241     }
 242
 243     /**
 244      * Old syntax of class constructor. Deprecated in PHP7.
 245      *
 246      * @deprecated since Moodle 3.1
 247      */
 248     public function question_category_object($page, $pageurl, $contexts, $currentcat, $defaultcategory, $todelete, $addcontexts) {
 249         debugging('Use of class name as constructor is deprecated', DEBUG_DEVELOPER);
 250         self::__construct($page, $pageurl, $contexts, $currentcat, $defaultcategory, $todelete, $addcontexts);
 251     }
 252
 253     /**
 254      * Initializes this classes general category-related variables
 255      */
 256     public function initialize($page, $contexts, $currentcat, $defaultcategory, $todelete, $addcontexts) {
 257         $lastlist = null;
 258         foreach ($contexts as $context){
 259             $this->editlists[$context->id] = new question_category_list('ul', '', true, $this->pageurl, $page, 'cpage', QUESTION_PAGE_LENGTH, $context);
 260             $this->editlists[$context->id]->lastlist =& $lastlist;
 261             if ($lastlist!== null){
 262                 $lastlist->nextlist =& $this->editlists[$context->id];
 263             }
 264             $lastlist =& $this->editlists[$context->id];
 265         }
 266
 267         $count = 1;
 268         $paged = false;
 269         foreach ($this->editlists as $key => $list){
 270             list($paged, $count) = $this->editlists[$key]->list_from_records($paged, $count);
 271         }
 272         $this->catform = new question_category_edit_form($this->pageurl, compact('contexts', 'currentcat'));
 273         if (!$currentcat){
 274             $this->catform->set_data(array('parent'=>$defaultcategory));
 275         }
 276     }
 277
 278     /**
 279      * Displays the user interface
 280      *
 281      */
 282     public function display_user_interface() {
 283
 284         /// Interface for editing existing categories
 285         $this->output_edit_lists();
 286
 287
 288         echo '<br />';
 289         /// Interface for adding a new category:
 290         $this->output_new_table();
 291         echo '<br />';
 292
 293     }
 294
 295     /**
 296      * Outputs a table to allow entry of a new category
 297      */
 298     public function output_new_table() {
 299         $this->catform->display();
 300     }
 301
 302     /**
 303      * Outputs a list to allow editing/rearranging of existing categories
 304      *
 305      * $this->initialize() must have already been called
 306      *
 307      */
 308     public function output_edit_lists() {
 309         global $OUTPUT;
 310
 311         echo $OUTPUT->heading_with_help(get_string('editcategories', 'question'), 'editcategories', 'question');
 312
 313         foreach ($this->editlists as $context => $list){
 314             $listhtml = $list->to_html(0, array('str'=>$this->str));
 315             if ($listhtml){
 316                 echo $OUTPUT->box_start('boxwidthwide boxaligncenter generalbox questioncategories contextlevel' . $list->context->contextlevel);
 317                 $fullcontext = context::instance_by_id($context);
 318                 echo $OUTPUT->heading(get_string('questioncatsfor', 'question', $fullcontext->get_context_name()), 3);
 319                 echo $listhtml;
 320                 echo $OUTPUT->box_end();
 321             }
 322         }
 323         echo $list->display_page_numbers();
 324      }
 325
 326     /**
 327      * gets all the courseids for the given categories
 328      *
 329      * @param array categories contains category objects in  a tree representation
 330      * @return array courseids flat array in form categoryid=>courseid
 331      */
 332     public function get_course_ids($categories) {
 333         $courseids = array();
 334         foreach ($categories as $key=>$cat) {
 335             $courseids[$key] = $cat->course;
 336             if (!empty($cat->children)) {
 337                 $courseids = array_merge($courseids, $this->get_course_ids($cat->children));
 338             }
 339         }
 340         return $courseids;
 341     }
 342
 343     public function edit_single_category($categoryid) {
 344     /// Interface for adding a new category
 345         global $DB;
 346         /// Interface for editing existing categories
 347         $category = $DB->get_record("question_categories", array("id" => $categoryid));
 348         if (empty($category)) {
 349             print_error('invalidcategory', '', '', $categoryid);
 350         } else if ($category->parent == 0) {
 351             print_error('cannotedittopcat', 'question', '', $categoryid);
 352         } else {
 353             $category->parent = "{$category->parent},{$category->contextid}";
 354             $category->submitbutton = get_string('savechanges');
 355             $category->categoryheader = $this->str->edit;
 356             $this->catform->set_data($category);
 357             $this->catform->display();
 358         }
 359     }
 360
 361     /**
 362      * Sets the viable parents
 363      *
 364      *  Viable parents are any except for the category itself, or any of it's descendants
 365      *  The parentstrings parameter is passed by reference and changed by this function.
 366      *
 367      * @param    array parentstrings a list of parentstrings
 368      * @param   object category
 369      */
 370     public function set_viable_parents(&$parentstrings, $category) {
 371
 372         unset($parentstrings[$category->id]);
 373         if (isset($category->children)) {
 374             foreach ($category->children as $child) {
 375                 $this->set_viable_parents($parentstrings, $child);
 376             }
 377         }
 378     }
 379
 380     /**
 381      * Gets question categories
 382      *
 383      * @param    int parent - if given, restrict records to those with this parent id.
 384      * @param    string sort - [[sortfield [,sortfield]] {ASC|DESC}]
 385      * @return   array categories
 386      */
 387     public function get_question_categories($parent=null, $sort="sortorder ASC") {
 388         global $COURSE, $DB;
 389         if (is_null($parent)) {
 390             $categories = $DB->get_records('question_categories', array('course' => $COURSE->id), $sort);
 391         } else {
 392             $select = "parent = ? AND course = ?";
 393             $categories = $DB->get_records_select('question_categories', $select, array($parent, $COURSE->id), $sort);
 394         }
 395         return $categories;
 396     }
 397
 398     /**
 399      * Deletes an existing question category
 400      *
 401      * @param int deletecat id of category to delete
 402      */
 403     public function delete_category($categoryid) {
 404         global $CFG, $DB;
 405         question_can_delete_cat($categoryid);
 406         if (!$category = $DB->get_record("question_categories", array("id" => $categoryid))) {  // security
 407             print_error('unknowcategory');
 408         }
 409         /// Send the children categories to live with their grandparent
 410         $DB->set_field("question_categories", "parent", $category->parent, array("parent" => $category->id));
 411
 412         /// Finally delete the category itself
 413         $DB->delete_records("question_categories", array("id" => $category->id));
 414
 415         // Log the deletion of this category.
 416         $event = \core\event\question_category_deleted::create_from_question_category_instance($category);
 417         $event->add_record_snapshot('question_categories', $category);
 418         $event->trigger();
 419
 420     }
 421
 422     public function move_questions_and_delete_category($oldcat, $newcat){
 423         question_can_delete_cat($oldcat);
 424         $this->move_questions($oldcat, $newcat);
 425         $this->delete_category($oldcat);
 426     }
 427
 428     public function display_move_form($questionsincategory, $category){
 429         global $OUTPUT;
 430         $vars = new stdClass();
 431         $vars->name = $category->name;
 432         $vars->count = $questionsincategory;
 433         echo $OUTPUT->box(get_string('categorymove', 'question', $vars), 'generalbox boxaligncenter');
 434         $this->moveform->display();
 435     }
 436
 437     public function move_questions($oldcat, $newcat){
 438         global $DB;
 439         $questionids = $DB->get_records_select_menu('question',
 440                 'category = ? AND (parent = 0 OR parent = id)', array($oldcat), '', 'id,1');
 441         question_move_questions_to_category(array_keys($questionids), $newcat);
 442     }
 443
 444     /**
 445      * Create a new category.
 446      *
 447      * Data is expected to come from question_category_edit_form.
 448      *
 449      * By default redirects on success, unless $return is true.
 450      *
 451      * @param string $newparent 'categoryid,contextid' of the parent category.
 452      * @param string $newcategory the name.
 453      * @param string $newinfo the description.
 454      * @param bool $return if true, return rather than redirecting.
 455      * @param int|string $newinfoformat description format. One of the FORMAT_ constants.
 456      * @param null $idnumber the idnumber. '' is converted to null.
 457      * @return bool|int New category id if successful, else false.
 458      */
 459     public function add_category($newparent, $newcategory, $newinfo, $return = false, $newinfoformat = FORMAT_HTML,
 460             $idnumber = null) {
 461         global $DB;
 462         if (empty($newcategory)) {
 463             print_error('categorynamecantbeblank', 'question');
 464         }
 465         list($parentid, $contextid) = explode(',', $newparent);
 466         //moodle_form makes sure select element output is legal no need for further cleaning
 467         require_capability('moodle/question:managecategory', context::instance_by_id($contextid));
 468
 469         if ($parentid) {
 470             if(!($DB->get_field('question_categories', 'contextid', array('id' => $parentid)) == $contextid)) {
 471                 print_error('cannotinsertquestioncatecontext', 'question', '', array('cat'=>$newcategory, 'ctx'=>$contextid));
 472             }
 473         }
 474
 475         if ((string) $idnumber === '') {
 476             $idnumber = null;
 477         } else if (!empty($contextid)) {
 478             // While this check already exists in the form validation, this is a backstop preventing unnecessary errors.
 479             if ($DB->record_exists('question_categories',
 480                     ['idnumber' => $idnumber, 'contextid' => $contextid])) {
 481                 $idnumber = null;
 482             }
 483         }
 484
 485         $cat = new stdClass();
 486         $cat->parent = $parentid;
 487         $cat->contextid = $contextid;
 488         $cat->name = $newcategory;
 489         $cat->info = $newinfo;
 490         $cat->infoformat = $newinfoformat;
 491         $cat->sortorder = 999;
 492         $cat->stamp = make_unique_id_code();
 493         $cat->idnumber = $idnumber;
 494         $categoryid = $DB->insert_record("question_categories", $cat);
 495
 496         // Log the creation of this category.
 497         $category = new stdClass();
 498         $category->id = $categoryid;
 499         $category->contextid = $contextid;
 500         $event = \core\event\question_category_created::create_from_question_category_instance($category);
 501         $event->trigger();
 502
 503         if ($return) {
 504             return $categoryid;
 505         } else {
 506             redirect($this->pageurl);//always redirect after successful action
 507         }
 508     }
 509
 510     /**
 511      * Updates an existing category with given params.
 512      *
 513      * Warning! parameter order and meaning confusingly different from add_category in some ways!
 514      *
 515      * @param int $updateid id of the category to update.
 516      * @param int $newparent 'categoryid,contextid' of the parent category to set.
 517      * @param string $newname category name.
 518      * @param string $newinfo category description.
 519      * @param int|string $newinfoformat description format. One of the FORMAT_ constants.
 520      * @param int $idnumber the idnumber. '' is converted to null.
 521      * @param bool $redirect if true, will redirect once the DB is updated (default).
 522      */
 523     public function update_category($updateid, $newparent, $newname, $newinfo, $newinfoformat = FORMAT_HTML,
 524             $idnumber = null, $redirect = true) {
 525         global $CFG, $DB;
 526         if (empty($newname)) {
 527             print_error('categorynamecantbeblank', 'question');
 528         }
 529
 530         // Get the record we are updating.
 531         $oldcat = $DB->get_record('question_categories', array('id' => $updateid));
 532         $lastcategoryinthiscontext = question_is_only_child_of_top_category_in_context($updateid);
 533
 534         if (!empty($newparent) && !$lastcategoryinthiscontext) {
 535             list($parentid, $tocontextid) = explode(',', $newparent);
 536         } else {
 537             $parentid = $oldcat->parent;
 538             $tocontextid = $oldcat->contextid;
 539         }
 540
 541         // Check permissions.
 542         $fromcontext = context::instance_by_id($oldcat->contextid);
 543         require_capability('moodle/question:managecategory', $fromcontext);
 544
 545         // If moving to another context, check permissions some more, and confirm contextid,stamp uniqueness.
 546         $newstamprequired = false;
 547         if ($oldcat->contextid != $tocontextid) {
 548             $tocontext = context::instance_by_id($tocontextid);
 549             require_capability('moodle/question:managecategory', $tocontext);
 550
 551             // Confirm stamp uniqueness in the new context. If the stamp already exists, generate a new one.
 552             if ($DB->record_exists('question_categories', array('contextid' => $tocontextid, 'stamp' => $oldcat->stamp))) {
 553                 $newstamprequired = true;
 554             }
 555         }
 556
 557         if ((string) $idnumber === '') {
 558             $idnumber = null;
 559         } else if (!empty($tocontextid)) {
 560             // While this check already exists in the form validation, this is a backstop preventing unnecessary errors.
 561             if ($DB->record_exists_select('question_categories',
 562                     'idnumber = ? AND contextid = ? AND id <> ?',
 563                     [$idnumber, $tocontextid, $updateid])) {
 564                 $idnumber = null;
 565             }
 566         }
 567
 568         // Update the category record.
 569         $cat = new stdClass();
 570         $cat->id = $updateid;
 571         $cat->name = $newname;
 572         $cat->info = $newinfo;
 573         $cat->infoformat = $newinfoformat;
 574         $cat->parent = $parentid;
 575         $cat->contextid = $tocontextid;
 576         $cat->idnumber = $idnumber;
 577         if ($newstamprequired) {
 578             $cat->stamp = make_unique_id_code();
 579         }
 580         $DB->update_record('question_categories', $cat);
 581
 582         // Log the update of this category.
 583         $event = \core\event\question_category_updated::create_from_question_category_instance($cat);
 584         $event->trigger();
 585
 586         // If the category name has changed, rename any random questions in that category.
 587         if ($oldcat->name != $cat->name) {
 588             $where = "qtype = 'random' AND category = ? AND " . $DB->sql_compare_text('questiontext') . " = ?";
 589
 590             $randomqtype = question_bank::get_qtype('random');
 591             $randomqname = $randomqtype->question_name($cat, false);
 592             $DB->set_field_select('question', 'name', $randomqname, $where, array($cat->id, '0'));
 593
 594             $randomqname = $randomqtype->question_name($cat, true);
 595             $DB->set_field_select('question', 'name', $randomqname, $where, array($cat->id, '1'));
 596         }
 597
 598         if ($oldcat->contextid != $tocontextid) {
 599             // Moving to a new context. Must move files belonging to questions.
 600             question_move_category_to_context($cat->id, $oldcat->contextid, $tocontextid);
 601         }
 602
 603         // Cat param depends on the context id, so update it.
 604         $this->pageurl->param('cat', $updateid . ',' . $tocontextid);
 605         if ($redirect) {
 606             redirect($this->pageurl); // Always redirect after successful action.
 607         }
 608     }
 609 }