enrol/cohort/lib.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  * Cohort enrolment plugin.
  19  *
  20  * @package    enrol_cohort
  21  * @copyright  2010 Petr Skoda {@link http://skodak.org}
  22  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24
  25 defined('MOODLE_INTERNAL') || die();
  26
  27 /**
  28  * COHORT_CREATEGROUP constant for automatically creating a group for a cohort.
  29  */
  30 define('COHORT_CREATE_GROUP', -1);
  31
  32 /**
  33  * COHORT_NOGROUP constant for using no group for a cohort.
  34  */
  35 define('COHORT_NOGROUP', 0);
  36
  37
  38 /**
  39  * Cohort enrolment plugin implementation.
  40  * @author Petr Skoda
  41  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  42  */
  43 class enrol_cohort_plugin extends enrol_plugin {
  44
  45     /**
  46      * Is it possible to delete enrol instance via standard UI?
  47      *
  48      * @param stdClass $instance
  49      * @return bool
  50      */
  51     public function can_delete_instance($instance) {
  52         $context = context_course::instance($instance->courseid);
  53         return has_capability('enrol/cohort:config', $context);
  54     }
  55
  56     /**
  57      * Returns localised name of enrol instance.
  58      *
  59      * @param stdClass $instance (null is accepted too)
  60      * @return string
  61      */
  62     public function get_instance_name($instance) {
  63         global $DB;
  64
  65         if (empty($instance)) {
  66             $enrol = $this->get_name();
  67             return get_string('pluginname', 'enrol_'.$enrol);
  68
  69         } else if (empty($instance->name)) {
  70             $enrol = $this->get_name();
  71             $cohort = $DB->get_record('cohort', array('id'=>$instance->customint1));
  72             if (!$cohort) {
  73                 return get_string('pluginname', 'enrol_'.$enrol);
  74             }
  75             $cohortname = format_string($cohort->name, true, array('context'=>context::instance_by_id($cohort->contextid)));
  76             if ($role = $DB->get_record('role', array('id'=>$instance->roleid))) {
  77                 $role = role_get_name($role, context_course::instance($instance->courseid, IGNORE_MISSING), ROLENAME_BOTH);
  78                 return get_string('pluginname', 'enrol_'.$enrol) . ' (' . $cohortname . ' - ' . $role .')';
  79             } else {
  80                 return get_string('pluginname', 'enrol_'.$enrol) . ' (' . $cohortname . ')';
  81             }
  82
  83         } else {
  84             return format_string($instance->name, true, array('context'=>context_course::instance($instance->courseid)));
  85         }
  86     }
  87
  88     /**
  89      * Given a courseid this function returns true if the user is able to enrol or configure cohorts.
  90      * AND there are cohorts that the user can view.
  91      *
  92      * @param int $courseid
  93      * @return bool
  94      */
  95     public function can_add_instance($courseid) {
  96         global $CFG;
  97         require_once($CFG->dirroot . '/cohort/lib.php');
  98         $coursecontext = context_course::instance($courseid);
  99         if (!has_capability('moodle/course:enrolconfig', $coursecontext) or !has_capability('enrol/cohort:config', $coursecontext)) {
 100             return false;
 101         }
 102         return cohort_get_available_cohorts($coursecontext, 0, 0, 1) ? true : false;
 103     }
 104
 105     /**
 106      * Add new instance of enrol plugin.
 107      * @param object $course
 108      * @param array $fields instance fields
 109      * @return int id of new instance, null if can not be created
 110      */
 111     public function add_instance($course, array $fields = null) {
 112         global $CFG;
 113
 114         // Allows multiple cohorts to be set on creation.
 115         if (!empty($fields['customint1'])) {
 116             $fields2 = $fields;
 117             if (!is_array($fields['customint1'])) {
 118                 $fields['customint1'] = array($fields['customint1']);
 119             }
 120             foreach ($fields['customint1'] as $cid) {
 121                 $fields2['customint1'] = $cid;
 122                 if (!empty($fields['customint2']) && $fields['customint2'] == COHORT_CREATE_GROUP) {
 123                     // Create a new group for the cohort if requested.
 124                     $context = context_course::instance($course->id);
 125                     require_capability('moodle/course:managegroups', $context);
 126                     $groupid = enrol_cohort_create_new_group($course->id, $cid);
 127                     $fields2['customint2'] = $groupid;
 128                 }
 129                 $result = parent::add_instance($course, $fields2);
 130             }
 131         } else {
 132             $result = parent::add_instance($course, $fields);
 133         }
 134         require_once("$CFG->dirroot/enrol/cohort/locallib.php");
 135         $trace = new null_progress_trace();
 136         enrol_cohort_sync($trace, $course->id);
 137         $trace->finished();
 138         return $result;
 139     }
 140
 141     /**
 142      * Update instance of enrol plugin.
 143      * @param stdClass $instance
 144      * @param stdClass $data modified instance fields
 145      * @return boolean
 146      */
 147     public function update_instance($instance, $data) {
 148         global $CFG;
 149
 150         // NOTE: no cohort changes here!!!
 151         $context = context_course::instance($instance->courseid);
 152         if ($data->roleid != $instance->roleid) {
 153             // The sync script can only add roles, for perf reasons it does not modify them.
 154             $params = array(
 155                 'contextid' => $context->id,
 156                 'roleid' => $instance->roleid,
 157                 'component' => 'enrol_cohort',
 158                 'itemid' => $instance->id
 159             );
 160             role_unassign_all($params);
 161         }
 162         // Create a new group for the cohort if requested.
 163         if ($data->customint2 == COHORT_CREATE_GROUP) {
 164             require_capability('moodle/course:managegroups', $context);
 165             $groupid = enrol_cohort_create_new_group($instance->courseid, $data->customint1);
 166             $data->customint2 = $groupid;
 167         }
 168
 169         $result = parent::update_instance($instance, $data);
 170
 171         require_once("$CFG->dirroot/enrol/cohort/locallib.php");
 172         $trace = new null_progress_trace();
 173         enrol_cohort_sync($trace, $instance->courseid);
 174         $trace->finished();
 175
 176         return $result;
 177     }
 178
 179     /**
 180      * Called after updating/inserting course.
 181      *
 182      * @param bool $inserted true if course just inserted
 183      * @param stdClass $course
 184      * @param stdClass $data form data
 185      * @return void
 186      */
 187     public function course_updated($inserted, $course, $data) {
 188         // It turns out there is no need for cohorts to deal with this hook, see MDL-34870.
 189     }
 190
 191     /**
 192      * Update instance status
 193      *
 194      * @param stdClass $instance
 195      * @param int $newstatus ENROL_INSTANCE_ENABLED, ENROL_INSTANCE_DISABLED
 196      * @return void
 197      */
 198     public function update_status($instance, $newstatus) {
 199         global $CFG;
 200
 201         parent::update_status($instance, $newstatus);
 202
 203         require_once("$CFG->dirroot/enrol/cohort/locallib.php");
 204         $trace = new null_progress_trace();
 205         enrol_cohort_sync($trace, $instance->courseid);
 206         $trace->finished();
 207     }
 208
 209     /**
 210      * Does this plugin allow manual unenrolment of a specific user?
 211      * Yes, but only if user suspended...
 212      *
 213      * @param stdClass $instance course enrol instance
 214      * @param stdClass $ue record from user_enrolments table
 215      *
 216      * @return bool - true means user with 'enrol/xxx:unenrol' may unenrol this user, false means nobody may touch this user enrolment
 217      */
 218     public function allow_unenrol_user(stdClass $instance, stdClass $ue) {
 219         if ($ue->status == ENROL_USER_SUSPENDED) {
 220             return true;
 221         }
 222
 223         return false;
 224     }
 225
 226     /**
 227      * Restore instance and map settings.
 228      *
 229      * @param restore_enrolments_structure_step $step
 230      * @param stdClass $data
 231      * @param stdClass $course
 232      * @param int $oldid
 233      */
 234     public function restore_instance(restore_enrolments_structure_step $step, stdClass $data, $course, $oldid) {
 235         global $DB, $CFG;
 236
 237         if (!$step->get_task()->is_samesite()) {
 238             // No cohort restore from other sites.
 239             $step->set_mapping('enrol', $oldid, 0);
 240             return;
 241         }
 242
 243         if (!empty($data->customint2)) {
 244             $data->customint2 = $step->get_mappingid('group', $data->customint2);
 245         }
 246
 247         if ($data->roleid and $DB->record_exists('cohort', array('id'=>$data->customint1))) {
 248             $instance = $DB->get_record('enrol', array('roleid'=>$data->roleid, 'customint1'=>$data->customint1, 'courseid'=>$course->id, 'enrol'=>$this->get_name()));
 249             if ($instance) {
 250                 $instanceid = $instance->id;
 251             } else {
 252                 $instanceid = $this->add_instance($course, (array)$data);
 253             }
 254             $step->set_mapping('enrol', $oldid, $instanceid);
 255
 256             require_once("$CFG->dirroot/enrol/cohort/locallib.php");
 257             $trace = new null_progress_trace();
 258             enrol_cohort_sync($trace, $course->id);
 259             $trace->finished();
 260
 261         } else if ($this->get_config('unenrolaction') == ENROL_EXT_REMOVED_SUSPENDNOROLES) {
 262             $data->customint1 = 0;
 263             $instance = $DB->get_record('enrol', array('roleid'=>$data->roleid, 'customint1'=>$data->customint1, 'courseid'=>$course->id, 'enrol'=>$this->get_name()));
 264
 265             if ($instance) {
 266                 $instanceid = $instance->id;
 267             } else {
 268                 $data->status = ENROL_INSTANCE_DISABLED;
 269                 $instanceid = $this->add_instance($course, (array)$data);
 270             }
 271             $step->set_mapping('enrol', $oldid, $instanceid);
 272
 273             require_once("$CFG->dirroot/enrol/cohort/locallib.php");
 274             $trace = new null_progress_trace();
 275             enrol_cohort_sync($trace, $course->id);
 276             $trace->finished();
 277
 278         } else {
 279             $step->set_mapping('enrol', $oldid, 0);
 280         }
 281     }
 282
 283     /**
 284      * Restore user enrolment.
 285      *
 286      * @param restore_enrolments_structure_step $step
 287      * @param stdClass $data
 288      * @param stdClass $instance
 289      * @param int $oldinstancestatus
 290      * @param int $userid
 291      */
 292     public function restore_user_enrolment(restore_enrolments_structure_step $step, $data, $instance, $userid, $oldinstancestatus) {
 293         global $DB;
 294
 295         if ($this->get_config('unenrolaction') != ENROL_EXT_REMOVED_SUSPENDNOROLES) {
 296             // Enrolments were already synchronised in restore_instance(), we do not want any suspended leftovers.
 297             return;
 298         }
 299
 300         // ENROL_EXT_REMOVED_SUSPENDNOROLES means all previous enrolments are restored
 301         // but without roles and suspended.
 302
 303         if (!$DB->record_exists('user_enrolments', array('enrolid'=>$instance->id, 'userid'=>$userid))) {
 304             $this->enrol_user($instance, $userid, null, $data->timestart, $data->timeend, ENROL_USER_SUSPENDED);
 305         }
 306     }
 307
 308     /**
 309      * Restore user group membership.
 310      * @param stdClass $instance
 311      * @param int $groupid
 312      * @param int $userid
 313      */
 314     public function restore_group_member($instance, $groupid, $userid) {
 315         // Nothing to do here, the group members are added in $this->restore_group_restored()
 316         return;
 317     }
 318
 319     /**
 320      * Is it possible to hide/show enrol instance via standard UI?
 321      *
 322      * @param stdClass $instance
 323      * @return bool
 324      */
 325     public function can_hide_show_instance($instance) {
 326         $context = context_course::instance($instance->courseid);
 327         return has_capability('enrol/cohort:config', $context);
 328     }
 329
 330     /**
 331      * Return an array of valid options for the status.
 332      *
 333      * @return array
 334      */
 335     protected function get_status_options() {
 336         $options = array(ENROL_INSTANCE_ENABLED  => get_string('yes'),
 337                          ENROL_INSTANCE_DISABLED => get_string('no'));
 338         return $options;
 339     }
 340
 341     /**
 342      * Return an array of valid options for the cohorts.
 343      *
 344      * @param stdClass $instance
 345      * @param context $context
 346      * @return array
 347      */
 348     protected function get_cohort_options($instance, $context) {
 349         global $DB, $CFG;
 350
 351         require_once($CFG->dirroot . '/cohort/lib.php');
 352
 353         $cohorts = array();
 354
 355         if ($instance->id) {
 356             if ($cohort = $DB->get_record('cohort', array('id' => $instance->customint1))) {
 357                 $name = format_string($cohort->name, true, array('context' => context::instance_by_id($cohort->contextid)));
 358                 $cohorts = array($instance->customint1 => $name);
 359             } else {
 360                 $cohorts = array($instance->customint1 => get_string('error'));
 361             }
 362         } else {
 363             $cohorts = array('' => get_string('choosedots'));
 364             $allcohorts = cohort_get_available_cohorts($context, 0, 0, 0);
 365             foreach ($allcohorts as $c) {
 366                 $cohorts[$c->id] = format_string($c->name);
 367             }
 368         }
 369         return $cohorts;
 370     }
 371
 372     /**
 373      * Return an array of valid options for the roles.
 374      *
 375      * @param stdClass $instance
 376      * @param context $coursecontext
 377      * @return array
 378      */
 379     protected function get_role_options($instance, $coursecontext) {
 380         global $DB;
 381
 382         $roles = get_assignable_roles($coursecontext, ROLENAME_BOTH);
 383         $roles[0] = get_string('none');
 384         $roles = array_reverse($roles, true); // Descending default sortorder.
 385
 386         // If the instance is already configured, but the configured role is no longer assignable in the course then add it back.
 387         if ($instance->id and !isset($roles[$instance->roleid])) {
 388             if ($role = $DB->get_record('role', array('id' => $instance->roleid))) {
 389                 $roles[$instance->roleid] = role_get_name($role, $coursecontext, ROLENAME_BOTH);
 390             } else {
 391                 $roles[$instance->roleid] = get_string('error');
 392             }
 393         }
 394
 395         return $roles;
 396     }
 397
 398     /**
 399      * Return an array of valid options for the groups.
 400      *
 401      * @param context $coursecontext
 402      * @return array
 403      */
 404     protected function get_group_options($coursecontext) {
 405         $groups = array(0 => get_string('none'));
 406         if (has_capability('moodle/course:managegroups', $coursecontext)) {
 407             $groups[COHORT_CREATE_GROUP] = get_string('creategroup', 'enrol_cohort');
 408         }
 409
 410         foreach (groups_get_all_groups($coursecontext->instanceid) as $group) {
 411             $groups[$group->id] = format_string($group->name, true, array('context' => $coursecontext));
 412         }
 413
 414         return $groups;
 415     }
 416
 417     /**
 418      * We are a good plugin and don't invent our own UI/validation code path.
 419      *
 420      * @return boolean
 421      */
 422     public function use_standard_editing_ui() {
 423         return true;
 424     }
 425
 426     /**
 427      * Add elements to the edit instance form.
 428      *
 429      * @param stdClass $instance
 430      * @param MoodleQuickForm $mform
 431      * @param context $coursecontext
 432      * @return bool
 433      */
 434     public function edit_instance_form($instance, MoodleQuickForm $mform, $coursecontext) {
 435
 436         $options = $this->get_status_options();
 437         $mform->addElement('select', 'status', get_string('status', 'enrol_cohort'), $options);
 438
 439         $options = ['contextid' => $coursecontext->id, 'multiple' => true];
 440         $mform->addElement('cohort', 'customint1', get_string('cohort', 'cohort'), $options);
 441
 442         if ($instance->id) {
 443             $mform->setConstant('customint1', $instance->customint1);
 444             $mform->hardFreeze('customint1', $instance->customint1);
 445         } else {
 446             $mform->addRule('customint1', get_string('required'), 'required', null, 'client');
 447         }
 448
 449         $roles = $this->get_role_options($instance, $coursecontext);
 450         $mform->addElement('select', 'roleid', get_string('assignrole', 'enrol_cohort'), $roles);
 451         $mform->setDefault('roleid', $this->get_config('roleid'));
 452         $groups = $this->get_group_options($coursecontext);
 453         $mform->addElement('select', 'customint2', get_string('addgroup', 'enrol_cohort'), $groups);
 454     }
 455
 456     /**
 457      * Perform custom validation of the data used to edit the instance.
 458      *
 459      * @param array $data array of ("fieldname" => value) of submitted data
 460      * @param array $files array of uploaded files "element_name" => tmp_file_path
 461      * @param object $instance The instance loaded from the DB
 462      * @param context $context The context of the instance we are editing
 463      * @return array of "element_name" => "error_description" if there are errors,
 464      *         or an empty array if everything is OK.
 465      * @return void
 466      */
 467     public function edit_instance_validation($data, $files, $instance, $context) {
 468         global $DB;
 469         $errors = array();
 470         // Allows multiple cohorts to be selected.
 471         list($sql1, $params1) = $DB->get_in_or_equal($data['customint1'], SQL_PARAMS_NAMED);
 472         $params = array(
 473             'roleid' => $data['roleid'],
 474             'courseid' => $data['courseid'],
 475             'id' => $data['id']
 476         );
 477         $params = array_merge($params, $params1);
 478         $sql = "roleid = :roleid AND customint1 $sql1 AND courseid = :courseid AND enrol = 'cohort' AND id <> :id";
 479         if ($DB->record_exists_select('enrol', $sql, $params)) {
 480             $errors['customint1'] = get_string('instanceexists', 'enrol_cohort');
 481         }
 482         $validstatus = array_keys($this->get_status_options());
 483         $validcohorts = array_keys($this->get_cohort_options($instance, $context));
 484         $validroles = array_keys($this->get_role_options($instance, $context));
 485         $validgroups = array_keys($this->get_group_options($context));
 486         $tovalidate = array(
 487             'status' => $validstatus,
 488             'roleid' => $validroles,
 489             'customint2' => $validgroups
 490         );
 491         $typeerrors = $this->validate_param_types($data, $tovalidate);
 492         // When creating a new cohort enrolment, we allow multiple cohorts in just one go.
 493         // When editing an existing enrolment, changing the cohort is no allowed, so cohort is a single value.
 494         if (is_array($data['customint1'])) {
 495             $cohorts = $data['customint1'];
 496         } else {
 497             $cohorts = [$data['customint1']];
 498         }
 499
 500         $errors = array_merge($errors, $typeerrors);
 501         // Check that the cohorts passed are valid.
 502         if (!empty(array_diff($cohorts, $validcohorts))) {
 503             $errors['customint1'] = get_string('invaliddata', 'error');
 504         }
 505         return $errors;
 506     }
 507
 508     /**
 509      * Check if data is valid for a given enrolment plugin
 510      *
 511      * @param array $enrolmentdata enrolment data to validate.
 512      * @param int|null $courseid Course ID.
 513      * @return array Errors
 514      */
 515     public function validate_enrol_plugin_data(array $enrolmentdata, ?int $courseid = null): array {
 516         global $DB;
 517
 518         $errors = [];
 519         if (!enrol_is_enabled('cohort')) {
 520             $errors['plugindisabled'] =
 521                 new lang_string('plugindisabled', 'enrol_cohort');
 522         }
 523
 524         if (isset($enrolmentdata['addtogroup'])) {
 525             $addtogroup = $enrolmentdata['addtogroup'];
 526             if (($addtogroup == - COHORT_CREATE_GROUP) || $addtogroup == COHORT_NOGROUP) {
 527                 if (isset($enrolmentdata['groupname'])) {
 528                     $errors['erroraddtogroupgroupname'] =
 529                         new lang_string('erroraddtogroupgroupname', 'group');
 530                 }
 531             } else {
 532                 $errors['erroraddtogroup'] =
 533                     new lang_string('erroraddtogroup', 'group');
 534             }
 535         }
 536
 537         if ($courseid) {
 538             $enrolmentdata = $this->fill_enrol_custom_fields($enrolmentdata, $courseid);
 539             $error = $this->validate_plugin_data_context($enrolmentdata, $courseid);
 540             if ($error) {
 541                 $errors['contextnotallowed'] = $error;
 542             }
 543
 544             if (isset($enrolmentdata['groupname']) && $enrolmentdata['groupname']) {
 545                 $groupname = $enrolmentdata['groupname'];
 546                 if (!groups_get_group_by_name($courseid, $groupname)) {
 547                     $errors['errorinvalidgroup'] =
 548                         new lang_string('errorinvalidgroup', 'group', $groupname);
 549                 }
 550             }
 551         }
 552
 553         if (!isset($enrolmentdata['cohortidnumber'])) {
 554             $missingmandatoryfields = 'cohortidnumber';
 555         } else {
 556             $cohortidnumber = $enrolmentdata['cohortidnumber'];
 557             // Cohort idnumber is unique.
 558             $cohortid = $DB->get_field('cohort', 'id', ['idnumber' => $cohortidnumber]);
 559
 560             if (!$cohortid) {
 561                 $errors['unknowncohort'] =
 562                     new lang_string('unknowncohort', 'cohort', $cohortidnumber);
 563             }
 564         }
 565
 566         if (!isset($enrolmentdata['role'])) {
 567             // We require role since we need it to identify enrol instance.
 568             if (isset($missingmandatoryfields)) {
 569                 $missingmandatoryfields .= ', role';
 570             } else {
 571                 $missingmandatoryfields = 'role';
 572             }
 573             $errors['missingmandatoryfields'] =
 574                 new lang_string('missingmandatoryfields', 'tool_uploadcourse',
 575                     $missingmandatoryfields);
 576         } else {
 577             $roleid = $DB->get_field('role', 'id', ['shortname' => $enrolmentdata['role']]);
 578             if (!$roleid) {
 579                 $errors['unknownrole'] =
 580                     new lang_string('unknownrole', 'error', s($enrolmentdata['role']));
 581             }
 582         }
 583
 584         return $errors;
 585     }
 586
 587     /**
 588      * Fill custom fields data for a given enrolment plugin.
 589      *
 590      * @param array $enrolmentdata enrolment data.
 591      * @param int $courseid Course ID.
 592      * @return array Updated enrolment data with custom fields info.
 593      */
 594     public function fill_enrol_custom_fields(array $enrolmentdata, int $courseid): array {
 595         global $DB;
 596
 597         if (isset($enrolmentdata['cohortidnumber'])) {
 598             // Cohort idnumber is unique.
 599             $enrolmentdata['customint1'] =
 600                 $DB->get_field('cohort', 'id', ['idnumber' => $enrolmentdata['cohortidnumber']]);
 601         }
 602
 603         if (isset($enrolmentdata['addtogroup'])) {
 604             if ($enrolmentdata['addtogroup'] == COHORT_NOGROUP) {
 605                 $enrolmentdata['customint2'] = COHORT_NOGROUP;
 606             } else if ($enrolmentdata['addtogroup'] == - COHORT_CREATE_GROUP) {
 607                 $enrolmentdata['customint2'] = COHORT_CREATE_GROUP;
 608             }
 609         } else if (isset($enrolmentdata['groupname'])) {
 610             $enrolmentdata['customint2'] = groups_get_group_by_name($courseid, $enrolmentdata['groupname']);
 611         }
 612         return $enrolmentdata;
 613     }
 614
 615     /**
 616      * Check if plugin custom data is allowed in relevant context.
 617      *
 618      * @param array $enrolmentdata enrolment data to validate.
 619      * @param int|null $courseid Course ID.
 620      * @return lang_string|null Error
 621      */
 622     public function validate_plugin_data_context(array $enrolmentdata, ?int $courseid = null): ?lang_string {
 623         $error = null;
 624         if (isset($enrolmentdata['customint1'])) {
 625             $cohortid = $enrolmentdata['customint1'];
 626             $coursecontext = \context_course::instance($courseid);
 627             if (!cohort_get_cohort($cohortid, $coursecontext)) {
 628                 $error = new lang_string('contextcohortnotallowed', 'cohort', $enrolmentdata['cohortidnumber']);
 629             }
 630         }
 631         return $error;
 632     }
 633
 634     /**
 635      * Add new instance of enrol plugin with custom settings,
 636      * called when adding new instance manually or when adding new course.
 637      * Used for example on course upload.
 638      *
 639      * Not all plugins support this.
 640      *
 641      * @param stdClass $course Course object
 642      * @param array|null $fields instance fields
 643      * @return int|null id of new instance or null if not supported
 644      */
 645     public function add_custom_instance(stdClass $course, ?array $fields = null): ?int {
 646         return $this->add_instance($course, $fields);
 647     }
 648
 649
 650     /**
 651      * Check if enrolment plugin is supported in csv course upload.
 652      *
 653      * @return bool
 654      */
 655     public function is_csv_upload_supported(): bool {
 656         return true;
 657     }
 658
 659     /**
 660      * Finds matching instances for a given course.
 661      *
 662      * @param array $enrolmentdata enrolment data.
 663      * @param int $courseid Course ID.
 664      * @return stdClass|null Matching instance
 665      */
 666     public function find_instance(array $enrolmentdata, int $courseid): ?stdClass {
 667         global $DB;
 668         $instances = enrol_get_instances($courseid, false);
 669
 670         $instance = null;
 671         if (isset($enrolmentdata['cohortidnumber']) && isset($enrolmentdata['role'])) {
 672             $cohortid = $DB->get_field('cohort', 'id', ['idnumber' => $enrolmentdata['cohortidnumber']]);
 673             $roleid = $DB->get_field('role', 'id', ['shortname' => $enrolmentdata['role']]);
 674             if ($cohortid && $roleid) {
 675                 foreach ($instances as $i) {
 676                     if ($i->enrol == 'cohort' && $i->customint1 == $cohortid && $i->roleid == $roleid) {
 677                         $instance = $i;
 678                         break;
 679                     }
 680                 }
 681             }
 682         }
 683         return $instance;
 684     }
 685 }
 686
 687 /**
 688  * Prevent removal of enrol roles.
 689  * @param int $itemid
 690  * @param int $groupid
 691  * @param int $userid
 692  * @return bool
 693  */
 694 function enrol_cohort_allow_group_member_remove($itemid, $groupid, $userid) {
 695     return false;
 696 }
 697
 698 /**
 699  * Create a new group with the cohorts name.
 700  *
 701  * @param int $courseid
 702  * @param int $cohortid
 703  * @return int $groupid Group ID for this cohort.
 704  */
 705 function enrol_cohort_create_new_group($courseid, $cohortid) {
 706     global $DB, $CFG;
 707
 708     require_once($CFG->dirroot . '/group/lib.php');
 709
 710     $groupname = $DB->get_field('cohort', 'name', array('id' => $cohortid), MUST_EXIST);
 711     $a = new stdClass();
 712     $a->name = $groupname;
 713     $a->increment = '';
 714     $groupname = trim(get_string('defaultgroupnametext', 'enrol_cohort', $a));
 715     $inc = 1;
 716     // Check to see if the cohort group name already exists. Add an incremented number if it does.
 717     while ($DB->record_exists('groups', array('name' => $groupname, 'courseid' => $courseid))) {
 718         $a->increment = '(' . (++$inc) . ')';
 719         $newshortname = trim(get_string('defaultgroupnametext', 'enrol_cohort', $a));
 720         $groupname = $newshortname;
 721     }
 722     // Create a new group for the cohort.
 723     $groupdata = new stdClass();
 724     $groupdata->courseid = $courseid;
 725     $groupdata->name = $groupname;
 726     $groupid = groups_create_group($groupdata);
 727
 728     return $groupid;
 729 }