group/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 /**
  19  * Extra library for groups and groupings.
  20  *
  21  * @copyright 2006 The Open University, J.White AT open.ac.uk, Petr Skoda (skodak)
  22  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  * @package   core_group
  24  */
  25
  26 /*
  27  * INTERNAL FUNCTIONS - to be used by moodle core only
  28  * require_once $CFG->dirroot.'/group/lib.php' must be used
  29  */
  30
  31 /**
  32  * Adds a specified user to a group
  33  *
  34  * @param mixed $grouporid  The group id or group object
  35  * @param mixed $userorid   The user id or user object
  36  * @param string $component Optional component name e.g. 'enrol_imsenterprise'
  37  * @param int $itemid Optional itemid associated with component
  38  * @return bool True if user added successfully or the user is already a
  39  * member of the group, false otherwise.
  40  */
  41 function groups_add_member($grouporid, $userorid, $component=null, $itemid=0) {
  42     global $DB;
  43
  44     if (is_object($userorid)) {
  45         $userid = $userorid->id;
  46         $user   = $userorid;
  47         if (!isset($user->deleted)) {
  48             $user = $DB->get_record('user', array('id'=>$userid), '*', MUST_EXIST);
  49         }
  50     } else {
  51         $userid = $userorid;
  52         $user = $DB->get_record('user', array('id'=>$userid), '*', MUST_EXIST);
  53     }
  54
  55     if ($user->deleted) {
  56         return false;
  57     }
  58
  59     if (is_object($grouporid)) {
  60         $groupid = $grouporid->id;
  61         $group   = $grouporid;
  62     } else {
  63         $groupid = $grouporid;
  64         $group = $DB->get_record('groups', array('id'=>$groupid), '*', MUST_EXIST);
  65     }
  66
  67     // Check if the user a participant of the group course.
  68     $context = context_course::instance($group->courseid);
  69     if (!is_enrolled($context, $userid)) {
  70         return false;
  71     }
  72
  73     if (groups_is_member($groupid, $userid)) {
  74         return true;
  75     }
  76
  77     $member = new stdClass();
  78     $member->groupid   = $groupid;
  79     $member->userid    = $userid;
  80     $member->timeadded = time();
  81     $member->component = '';
  82     $member->itemid = 0;
  83
  84     // Check the component exists if specified
  85     if (!empty($component)) {
  86         $dir = core_component::get_component_directory($component);
  87         if ($dir && is_dir($dir)) {
  88             // Component exists and can be used
  89             $member->component = $component;
  90             $member->itemid = $itemid;
  91         } else {
  92             throw new coding_exception('Invalid call to groups_add_member(). An invalid component was specified');
  93         }
  94     }
  95
  96     if ($itemid !== 0 && empty($member->component)) {
  97         // An itemid can only be specified if a valid component was found
  98         throw new coding_exception('Invalid call to groups_add_member(). A component must be specified if an itemid is given');
  99     }
 100
 101     $DB->insert_record('groups_members', $member);
 102
 103     // Update group info, and group object.
 104     $DB->set_field('groups', 'timemodified', $member->timeadded, array('id'=>$groupid));
 105     $group->timemodified = $member->timeadded;
 106
 107     // Trigger group event.
 108     $params = array(
 109         'context' => $context,
 110         'objectid' => $groupid,
 111         'relateduserid' => $userid,
 112         'other' => array(
 113             'component' => $member->component,
 114             'itemid' => $member->itemid
 115         )
 116     );
 117     $event = \core\event\group_member_added::create($params);
 118     $event->add_record_snapshot('groups', $group);
 119     $event->trigger();
 120
 121     return true;
 122 }
 123
 124 /**
 125  * Checks whether the current user is permitted (using the normal UI) to
 126  * remove a specific group member, assuming that they have access to remove
 127  * group members in general.
 128  *
 129  * For automatically-created group member entries, this checks with the
 130  * relevant plugin to see whether it is permitted. The default, if the plugin
 131  * doesn't provide a function, is true.
 132  *
 133  * For other entries (and any which have already been deleted/don't exist) it
 134  * just returns true.
 135  *
 136  * @param mixed $grouporid The group id or group object
 137  * @param mixed $userorid The user id or user object
 138  * @return bool True if permitted, false otherwise
 139  */
 140 function groups_remove_member_allowed($grouporid, $userorid) {
 141     global $DB;
 142
 143     if (is_object($userorid)) {
 144         $userid = $userorid->id;
 145     } else {
 146         $userid = $userorid;
 147     }
 148     if (is_object($grouporid)) {
 149         $groupid = $grouporid->id;
 150     } else {
 151         $groupid = $grouporid;
 152     }
 153
 154     // Get entry
 155     if (!($entry = $DB->get_record('groups_members',
 156             array('groupid' => $groupid, 'userid' => $userid), '*', IGNORE_MISSING))) {
 157         // If the entry does not exist, they are allowed to remove it (this
 158         // is consistent with groups_remove_member below).
 159         return true;
 160     }
 161
 162     // If the entry does not have a component value, they can remove it
 163     if (empty($entry->component)) {
 164         return true;
 165     }
 166
 167     // It has a component value, so we need to call a plugin function (if it
 168     // exists); the default is to allow removal
 169     return component_callback($entry->component, 'allow_group_member_remove',
 170             array($entry->itemid, $entry->groupid, $entry->userid), true);
 171 }
 172
 173 /**
 174  * Deletes the link between the specified user and group.
 175  *
 176  * @param mixed $grouporid  The group id or group object
 177  * @param mixed $userorid   The user id or user object
 178  * @return bool True if deletion was successful, false otherwise
 179  */
 180 function groups_remove_member($grouporid, $userorid) {
 181     global $DB;
 182
 183     if (is_object($userorid)) {
 184         $userid = $userorid->id;
 185     } else {
 186         $userid = $userorid;
 187     }
 188
 189     if (is_object($grouporid)) {
 190         $groupid = $grouporid->id;
 191         $group   = $grouporid;
 192     } else {
 193         $groupid = $grouporid;
 194         $group = $DB->get_record('groups', array('id'=>$groupid), '*', MUST_EXIST);
 195     }
 196
 197     if (!groups_is_member($groupid, $userid)) {
 198         return true;
 199     }
 200
 201     $DB->delete_records('groups_members', array('groupid'=>$groupid, 'userid'=>$userid));
 202
 203     // Update group info.
 204     $time = time();
 205     $DB->set_field('groups', 'timemodified', $time, array('id' => $groupid));
 206     $group->timemodified = $time;
 207
 208     // Trigger group event.
 209     $params = array(
 210         'context' => context_course::instance($group->courseid),
 211         'objectid' => $groupid,
 212         'relateduserid' => $userid
 213     );
 214     $event = \core\event\group_member_removed::create($params);
 215     $event->add_record_snapshot('groups', $group);
 216     $event->trigger();
 217
 218     return true;
 219 }
 220
 221 /**
 222  * Add a new group
 223  *
 224  * @param stdClass $data group properties
 225  * @param stdClass $editform
 226  * @param array $editoroptions
 227  * @return id of group or false if error
 228  */
 229 function groups_create_group($data, $editform = false, $editoroptions = false) {
 230     global $CFG, $DB;
 231
 232     //check that courseid exists
 233     $course = $DB->get_record('course', array('id' => $data->courseid), '*', MUST_EXIST);
 234     $context = context_course::instance($course->id);
 235
 236     $data->timecreated  = time();
 237     $data->timemodified = $data->timecreated;
 238     $data->name         = trim($data->name);
 239     if (isset($data->idnumber)) {
 240         $data->idnumber = trim($data->idnumber);
 241         if (groups_get_group_by_idnumber($course->id, $data->idnumber)) {
 242             throw new moodle_exception('idnumbertaken');
 243         }
 244     }
 245
 246     if ($editform and $editoroptions) {
 247         $data->description = $data->description_editor['text'];
 248         $data->descriptionformat = $data->description_editor['format'];
 249     }
 250
 251     $data->id = $DB->insert_record('groups', $data);
 252
 253     if ($editform and $editoroptions) {
 254         // Update description from editor with fixed files
 255         $data = file_postupdate_standard_editor($data, 'description', $editoroptions, $context, 'group', 'description', $data->id);
 256         $upd = new stdClass();
 257         $upd->id                = $data->id;
 258         $upd->description       = $data->description;
 259         $upd->descriptionformat = $data->descriptionformat;
 260         $DB->update_record('groups', $upd);
 261     }
 262
 263     $group = $DB->get_record('groups', array('id'=>$data->id));
 264
 265     if ($editform) {
 266         groups_update_group_icon($group, $data, $editform);
 267     }
 268
 269     // Invalidate the grouping cache for the course
 270     cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($course->id));
 271
 272     // Trigger group event.
 273     $params = array(
 274         'context' => $context,
 275         'objectid' => $group->id
 276     );
 277     $event = \core\event\group_created::create($params);
 278     $event->add_record_snapshot('groups', $group);
 279     $event->trigger();
 280
 281     return $group->id;
 282 }
 283
 284 /**
 285  * Add a new grouping
 286  *
 287  * @param stdClass $data grouping properties
 288  * @param array $editoroptions
 289  * @return id of grouping or false if error
 290  */
 291 function groups_create_grouping($data, $editoroptions=null) {
 292     global $DB;
 293
 294     $data->timecreated  = time();
 295     $data->timemodified = $data->timecreated;
 296     $data->name         = trim($data->name);
 297     if (isset($data->idnumber)) {
 298         $data->idnumber = trim($data->idnumber);
 299         if (groups_get_grouping_by_idnumber($data->courseid, $data->idnumber)) {
 300             throw new moodle_exception('idnumbertaken');
 301         }
 302     }
 303
 304     if ($editoroptions !== null) {
 305         $data->description = $data->description_editor['text'];
 306         $data->descriptionformat = $data->description_editor['format'];
 307     }
 308
 309     $id = $DB->insert_record('groupings', $data);
 310     $data->id = $id;
 311
 312     if ($editoroptions !== null) {
 313         $description = new stdClass;
 314         $description->id = $data->id;
 315         $description->description_editor = $data->description_editor;
 316         $description = file_postupdate_standard_editor($description, 'description', $editoroptions, $editoroptions['context'], 'grouping', 'description', $description->id);
 317         $DB->update_record('groupings', $description);
 318     }
 319
 320     // Invalidate the grouping cache for the course
 321     cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($data->courseid));
 322
 323     // Trigger group event.
 324     $params = array(
 325         'context' => context_course::instance($data->courseid),
 326         'objectid' => $id
 327     );
 328     $event = \core\event\grouping_created::create($params);
 329     $event->set_legacy_eventdata($data);
 330     $event->trigger();
 331
 332     return $id;
 333 }
 334
 335 /**
 336  * Update the group icon from form data
 337  *
 338  * @param stdClass $group group information
 339  * @param stdClass $data
 340  * @param stdClass $editform
 341  */
 342 function groups_update_group_icon($group, $data, $editform) {
 343     global $CFG, $DB;
 344     require_once("$CFG->libdir/gdlib.php");
 345
 346     $fs = get_file_storage();
 347     $context = context_course::instance($group->courseid, MUST_EXIST);
 348
 349     //TODO: it would make sense to allow picture deleting too (skodak)
 350     if ($iconfile = $editform->save_temp_file('imagefile')) {
 351         if (process_new_icon($context, 'group', 'icon', $group->id, $iconfile)) {
 352             $DB->set_field('groups', 'picture', 1, array('id'=>$group->id));
 353             $group->picture = 1;
 354         } else {
 355             $fs->delete_area_files($context->id, 'group', 'icon', $group->id);
 356             $DB->set_field('groups', 'picture', 0, array('id'=>$group->id));
 357             $group->picture = 0;
 358         }
 359         @unlink($iconfile);
 360         // Invalidate the group data as we've updated the group record.
 361         cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($group->courseid));
 362     }
 363 }
 364
 365 /**
 366  * Update group
 367  *
 368  * @param stdClass $data group properties (with magic quotes)
 369  * @param stdClass $editform
 370  * @param array $editoroptions
 371  * @return bool true or exception
 372  */
 373 function groups_update_group($data, $editform = false, $editoroptions = false) {
 374     global $CFG, $DB;
 375
 376     $context = context_course::instance($data->courseid);
 377
 378     $data->timemodified = time();
 379     $data->name         = trim($data->name);
 380     if (isset($data->idnumber)) {
 381         $data->idnumber = trim($data->idnumber);
 382         if (($existing = groups_get_group_by_idnumber($data->courseid, $data->idnumber)) && $existing->id != $data->id) {
 383             throw new moodle_exception('idnumbertaken');
 384         }
 385     }
 386
 387     if ($editform and $editoroptions) {
 388         $data = file_postupdate_standard_editor($data, 'description', $editoroptions, $context, 'group', 'description', $data->id);
 389     }
 390
 391     $DB->update_record('groups', $data);
 392
 393     // Invalidate the group data.
 394     cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($data->courseid));
 395
 396     $group = $DB->get_record('groups', array('id'=>$data->id));
 397
 398     if ($editform) {
 399         groups_update_group_icon($group, $data, $editform);
 400     }
 401
 402     // Trigger group event.
 403     $params = array(
 404         'context' => $context,
 405         'objectid' => $group->id
 406     );
 407     $event = \core\event\group_updated::create($params);
 408     $event->add_record_snapshot('groups', $group);
 409     $event->trigger();
 410
 411     return true;
 412 }
 413
 414 /**
 415  * Update grouping
 416  *
 417  * @param stdClass $data grouping properties (with magic quotes)
 418  * @param array $editoroptions
 419  * @return bool true or exception
 420  */
 421 function groups_update_grouping($data, $editoroptions=null) {
 422     global $DB;
 423     $data->timemodified = time();
 424     $data->name         = trim($data->name);
 425     if (isset($data->idnumber)) {
 426         $data->idnumber = trim($data->idnumber);
 427         if (($existing = groups_get_grouping_by_idnumber($data->courseid, $data->idnumber)) && $existing->id != $data->id) {
 428             throw new moodle_exception('idnumbertaken');
 429         }
 430     }
 431     if ($editoroptions !== null) {
 432         $data = file_postupdate_standard_editor($data, 'description', $editoroptions, $editoroptions['context'], 'grouping', 'description', $data->id);
 433     }
 434     $DB->update_record('groupings', $data);
 435
 436     // Invalidate the group data.
 437     cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($data->courseid));
 438
 439     // Trigger group event.
 440     $params = array(
 441         'context' => context_course::instance($data->courseid),
 442         'objectid' => $data->id
 443     );
 444     $event = \core\event\grouping_updated::create($params);
 445     $event->set_legacy_eventdata($data);
 446     $event->trigger();
 447
 448     return true;
 449 }
 450
 451 /**
 452  * Delete a group best effort, first removing members and links with courses and groupings.
 453  * Removes group avatar too.
 454  *
 455  * @param mixed $grouporid The id of group to delete or full group object
 456  * @return bool True if deletion was successful, false otherwise
 457  */
 458 function groups_delete_group($grouporid) {
 459     global $CFG, $DB;
 460     require_once("$CFG->libdir/gdlib.php");
 461
 462     if (is_object($grouporid)) {
 463         $groupid = $grouporid->id;
 464         $group   = $grouporid;
 465     } else {
 466         $groupid = $grouporid;
 467         if (!$group = $DB->get_record('groups', array('id'=>$groupid))) {
 468             //silently ignore attempts to delete missing already deleted groups ;-)
 469             return true;
 470         }
 471     }
 472
 473     // delete group calendar events
 474     $DB->delete_records('event', array('groupid'=>$groupid));
 475     //first delete usage in groupings_groups
 476     $DB->delete_records('groupings_groups', array('groupid'=>$groupid));
 477     //delete members
 478     $DB->delete_records('groups_members', array('groupid'=>$groupid));
 479     //group itself last
 480     $DB->delete_records('groups', array('id'=>$groupid));
 481
 482     // Delete all files associated with this group
 483     $context = context_course::instance($group->courseid);
 484     $fs = get_file_storage();
 485     $fs->delete_area_files($context->id, 'group', 'description', $groupid);
 486     $fs->delete_area_files($context->id, 'group', 'icon', $groupid);
 487
 488     // Invalidate the grouping cache for the course
 489     cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($group->courseid));
 490
 491     // Trigger group event.
 492     $params = array(
 493         'context' => $context,
 494         'objectid' => $groupid
 495     );
 496     $event = \core\event\group_deleted::create($params);
 497     $event->add_record_snapshot('groups', $group);
 498     $event->trigger();
 499
 500     return true;
 501 }
 502
 503 /**
 504  * Delete grouping
 505  *
 506  * @param int $groupingorid
 507  * @return bool success
 508  */
 509 function groups_delete_grouping($groupingorid) {
 510     global $DB;
 511
 512     if (is_object($groupingorid)) {
 513         $groupingid = $groupingorid->id;
 514         $grouping   = $groupingorid;
 515     } else {
 516         $groupingid = $groupingorid;
 517         if (!$grouping = $DB->get_record('groupings', array('id'=>$groupingorid))) {
 518             //silently ignore attempts to delete missing already deleted groupings ;-)
 519             return true;
 520         }
 521     }
 522
 523     //first delete usage in groupings_groups
 524     $DB->delete_records('groupings_groups', array('groupingid'=>$groupingid));
 525     // remove the default groupingid from course
 526     $DB->set_field('course', 'defaultgroupingid', 0, array('defaultgroupingid'=>$groupingid));
 527     // remove the groupingid from all course modules
 528     $DB->set_field('course_modules', 'groupingid', 0, array('groupingid'=>$groupingid));
 529     //group itself last
 530     $DB->delete_records('groupings', array('id'=>$groupingid));
 531
 532     $context = context_course::instance($grouping->courseid);
 533     $fs = get_file_storage();
 534     $files = $fs->get_area_files($context->id, 'grouping', 'description', $groupingid);
 535     foreach ($files as $file) {
 536         $file->delete();
 537     }
 538
 539     // Invalidate the grouping cache for the course
 540     cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($grouping->courseid));
 541
 542     // Trigger group event.
 543     $params = array(
 544         'context' => $context,
 545         'objectid' => $groupingid
 546     );
 547     $event = \core\event\grouping_deleted::create($params);
 548     $event->add_record_snapshot('groupings', $grouping);
 549     $event->trigger();
 550
 551     return true;
 552 }
 553
 554 /**
 555  * Remove all users (or one user) from all groups in course
 556  *
 557  * @param int $courseid
 558  * @param int $userid 0 means all users
 559  * @param bool $showfeedback
 560  * @return bool success
 561  */
 562 function groups_delete_group_members($courseid, $userid=0, $showfeedback=false) {
 563     global $DB, $OUTPUT;
 564
 565     if (is_bool($userid)) {
 566         debugging('Incorrect userid function parameter');
 567         return false;
 568     }
 569
 570     // Select * so that the function groups_remove_member() gets the whole record.
 571     $groups = $DB->get_recordset('groups', array('courseid' => $courseid));
 572     foreach ($groups as $group) {
 573         if ($userid) {
 574             $userids = array($userid);
 575         } else {
 576             $userids = $DB->get_fieldset_select('groups_members', 'userid', 'groupid = :groupid', array('groupid' => $group->id));
 577         }
 578
 579         foreach ($userids as $id) {
 580             groups_remove_member($group, $id);
 581         }
 582     }
 583
 584     // TODO MDL-41312 Remove events_trigger_legacy('groups_members_removed').
 585     // This event is kept here for backwards compatibility, because it cannot be
 586     // translated to a new event as it is wrong.
 587     $eventdata = new stdClass();
 588     $eventdata->courseid = $courseid;
 589     $eventdata->userid   = $userid;
 590     events_trigger_legacy('groups_members_removed', $eventdata);
 591
 592     if ($showfeedback) {
 593         echo $OUTPUT->notification(get_string('deleted').' - '.get_string('groupmembers', 'group'), 'notifysuccess');
 594     }
 595
 596     return true;
 597 }
 598
 599 /**
 600  * Remove all groups from all groupings in course
 601  *
 602  * @param int $courseid
 603  * @param bool $showfeedback
 604  * @return bool success
 605  */
 606 function groups_delete_groupings_groups($courseid, $showfeedback=false) {
 607     global $DB, $OUTPUT;
 608
 609     $groupssql = "SELECT id FROM {groups} g WHERE g.courseid = ?";
 610     $results = $DB->get_recordset_select('groupings_groups', "groupid IN ($groupssql)",
 611         array($courseid), '', 'groupid, groupingid');
 612
 613     foreach ($results as $result) {
 614         groups_unassign_grouping($result->groupingid, $result->groupid, false);
 615     }
 616
 617     // Invalidate the grouping cache for the course
 618     cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($courseid));
 619
 620     // TODO MDL-41312 Remove events_trigger_legacy('groups_groupings_groups_removed').
 621     // This event is kept here for backwards compatibility, because it cannot be
 622     // translated to a new event as it is wrong.
 623     events_trigger_legacy('groups_groupings_groups_removed', $courseid);
 624
 625     // no need to show any feedback here - we delete usually first groupings and then groups
 626
 627     return true;
 628 }
 629
 630 /**
 631  * Delete all groups from course
 632  *
 633  * @param int $courseid
 634  * @param bool $showfeedback
 635  * @return bool success
 636  */
 637 function groups_delete_groups($courseid, $showfeedback=false) {
 638     global $CFG, $DB, $OUTPUT;
 639
 640     $groups = $DB->get_recordset('groups', array('courseid' => $courseid));
 641     foreach ($groups as $group) {
 642         groups_delete_group($group);
 643     }
 644
 645     // Invalidate the grouping cache for the course
 646     cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($courseid));
 647
 648     // TODO MDL-41312 Remove events_trigger_legacy('groups_groups_deleted').
 649     // This event is kept here for backwards compatibility, because it cannot be
 650     // translated to a new event as it is wrong.
 651     events_trigger_legacy('groups_groups_deleted', $courseid);
 652
 653     if ($showfeedback) {
 654         echo $OUTPUT->notification(get_string('deleted').' - '.get_string('groups', 'group'), 'notifysuccess');
 655     }
 656
 657     return true;
 658 }
 659
 660 /**
 661  * Delete all groupings from course
 662  *
 663  * @param int $courseid
 664  * @param bool $showfeedback
 665  * @return bool success
 666  */
 667 function groups_delete_groupings($courseid, $showfeedback=false) {
 668     global $DB, $OUTPUT;
 669
 670     $groupings = $DB->get_recordset_select('groupings', 'courseid = ?', array($courseid));
 671     foreach ($groupings as $grouping) {
 672         groups_delete_grouping($grouping);
 673     }
 674
 675     // Invalidate the grouping cache for the course.
 676     cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($courseid));
 677
 678     // TODO MDL-41312 Remove events_trigger_legacy('groups_groupings_deleted').
 679     // This event is kept here for backwards compatibility, because it cannot be
 680     // translated to a new event as it is wrong.
 681     events_trigger_legacy('groups_groupings_deleted', $courseid);
 682
 683     if ($showfeedback) {
 684         echo $OUTPUT->notification(get_string('deleted').' - '.get_string('groupings', 'group'), 'notifysuccess');
 685     }
 686
 687     return true;
 688 }
 689
 690 /* =================================== */
 691 /* various functions used by groups UI */
 692 /* =================================== */
 693
 694 /**
 695  * Obtains a list of the possible roles that group members might come from,
 696  * on a course. Generally this includes only profile roles.
 697  *
 698  * @param context $context Context of course
 699  * @return Array of role ID integers, or false if error/none.
 700  */
 701 function groups_get_possible_roles($context) {
 702     $roles = get_profile_roles($context);
 703     return array_keys($roles);
 704 }
 705
 706
 707 /**
 708  * Gets potential group members for grouping
 709  *
 710  * @param int $courseid The id of the course
 711  * @param int $roleid The role to select users from
 712  * @param int $cohortid restrict to cohort id
 713  * @param string $orderby The column to sort users by
 714  * @return array An array of the users
 715  */
 716 function groups_get_potential_members($courseid, $roleid = null, $cohortid = null, $orderby = 'lastname ASC, firstname ASC') {
 717     global $DB;
 718
 719     $context = context_course::instance($courseid);
 720
 721     list($esql, $params) = get_enrolled_sql($context);
 722
 723     if ($roleid) {
 724         // We are looking for all users with this role assigned in this context or higher.
 725         list($relatedctxsql, $relatedctxparams) = $DB->get_in_or_equal($context->get_parent_context_ids(true), SQL_PARAMS_NAMED, 'relatedctx');
 726
 727         $params = array_merge($params, $relatedctxparams, array('roleid' => $roleid));
 728         $where = "WHERE u.id IN (SELECT userid
 729                                    FROM {role_assignments}
 730                                   WHERE roleid = :roleid AND contextid $relatedctxsql)";
 731     } else {
 732         $where = "";
 733     }
 734
 735     if ($cohortid) {
 736         $cohortjoin = "JOIN {cohort_members} cm ON (cm.userid = u.id AND cm.cohortid = :cohortid)";
 737         $params['cohortid'] = $cohortid;
 738     } else {
 739         $cohortjoin = "";
 740     }
 741
 742     $allusernamefields = get_all_user_name_fields(true, 'u');
 743     $sql = "SELECT u.id, u.username, $allusernamefields, u.idnumber
 744               FROM {user} u
 745               JOIN ($esql) e ON e.id = u.id
 746        $cohortjoin
 747             $where
 748           ORDER BY $orderby";
 749
 750     return $DB->get_records_sql($sql, $params);
 751
 752 }
 753
 754 /**
 755  * Parse a group name for characters to replace
 756  *
 757  * @param string $format The format a group name will follow
 758  * @param int $groupnumber The number of the group to be used in the parsed format string
 759  * @return string the parsed format string
 760  */
 761 function groups_parse_name($format, $groupnumber) {
 762     if (strstr($format, '@') !== false) { // Convert $groupnumber to a character series
 763         $letter = 'A';
 764         for($i=0; $i<$groupnumber; $i++) {
 765             $letter++;
 766         }
 767         $str = str_replace('@', $letter, $format);
 768     } else {
 769         $str = str_replace('#', $groupnumber+1, $format);
 770     }
 771     return($str);
 772 }
 773
 774 /**
 775  * Assigns group into grouping
 776  *
 777  * @param int groupingid
 778  * @param int groupid
 779  * @param int $timeadded  The time the group was added to the grouping.
 780  * @param bool $invalidatecache If set to true the course group cache will be invalidated as well.
 781  * @return bool true or exception
 782  */
 783 function groups_assign_grouping($groupingid, $groupid, $timeadded = null, $invalidatecache = true) {
 784     global $DB;
 785
 786     if ($DB->record_exists('groupings_groups', array('groupingid'=>$groupingid, 'groupid'=>$groupid))) {
 787         return true;
 788     }
 789     $assign = new stdClass();
 790     $assign->groupingid = $groupingid;
 791     $assign->groupid    = $groupid;
 792     if ($timeadded != null) {
 793         $assign->timeadded = (integer)$timeadded;
 794     } else {
 795         $assign->timeadded = time();
 796     }
 797     $DB->insert_record('groupings_groups', $assign);
 798
 799     if ($invalidatecache) {
 800         // Invalidate the grouping cache for the course
 801         $courseid = $DB->get_field('groupings', 'courseid', array('id' => $groupingid));
 802         cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($courseid));
 803     }
 804
 805     return true;
 806 }
 807
 808 /**
 809  * Unassigns group from grouping
 810  *
 811  * @param int groupingid
 812  * @param int groupid
 813  * @param bool $invalidatecache If set to true the course group cache will be invalidated as well.
 814  * @return bool success
 815  */
 816 function groups_unassign_grouping($groupingid, $groupid, $invalidatecache = true) {
 817     global $DB;
 818     $DB->delete_records('groupings_groups', array('groupingid'=>$groupingid, 'groupid'=>$groupid));
 819
 820     if ($invalidatecache) {
 821         // Invalidate the grouping cache for the course
 822         $courseid = $DB->get_field('groupings', 'courseid', array('id' => $groupingid));
 823         cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($courseid));
 824     }
 825
 826     return true;
 827 }
 828
 829 /**
 830  * Lists users in a group based on their role on the course.
 831  * Returns false if there's an error or there are no users in the group.
 832  * Otherwise returns an array of role ID => role data, where role data includes:
 833  * (role) $id, $shortname, $name
 834  * $users: array of objects for each user which include the specified fields
 835  * Users who do not have a role are stored in the returned array with key '-'
 836  * and pseudo-role details (including a name, 'No role'). Users with multiple
 837  * roles, same deal with key '*' and name 'Multiple roles'. You can find out
 838  * which roles each has by looking in the $roles array of the user object.
 839  *
 840  * @param int $groupid
 841  * @param int $courseid Course ID (should match the group's course)
 842  * @param string $fields List of fields from user table prefixed with u, default 'u.*'
 843  * @param string $sort SQL ORDER BY clause, default (when null passed) is what comes from users_order_by_sql.
 844  * @param string $extrawheretest extra SQL conditions ANDed with the existing where clause.
 845  * @param array $whereorsortparams any parameters required by $extrawheretest (named parameters).
 846  * @return array Complex array as described above
 847  */
 848 function groups_get_members_by_role($groupid, $courseid, $fields='u.*',
 849         $sort=null, $extrawheretest='', $whereorsortparams=array()) {
 850     global $DB;
 851
 852     // Retrieve information about all users and their roles on the course or
 853     // parent ('related') contexts
 854     $context = context_course::instance($courseid);
 855
 856     // We are looking for all users with this role assigned in this context or higher.
 857     list($relatedctxsql, $relatedctxparams) = $DB->get_in_or_equal($context->get_parent_context_ids(true), SQL_PARAMS_NAMED, 'relatedctx');
 858
 859     if ($extrawheretest) {
 860         $extrawheretest = ' AND ' . $extrawheretest;
 861     }
 862
 863     if (is_null($sort)) {
 864         list($sort, $sortparams) = users_order_by_sql('u');
 865         $whereorsortparams = array_merge($whereorsortparams, $sortparams);
 866     }
 867
 868     $sql = "SELECT r.id AS roleid, u.id AS userid, $fields
 869               FROM {groups_members} gm
 870               JOIN {user} u ON u.id = gm.userid
 871          LEFT JOIN {role_assignments} ra ON (ra.userid = u.id AND ra.contextid $relatedctxsql)
 872          LEFT JOIN {role} r ON r.id = ra.roleid
 873              WHERE gm.groupid=:mgroupid
 874                    ".$extrawheretest."
 875           ORDER BY r.sortorder, $sort";
 876     $whereorsortparams = array_merge($whereorsortparams, $relatedctxparams, array('mgroupid' => $groupid));
 877     $rs = $DB->get_recordset_sql($sql, $whereorsortparams);
 878
 879     return groups_calculate_role_people($rs, $context);
 880 }
 881
 882 /**
 883  * Internal function used by groups_get_members_by_role to handle the
 884  * results of a database query that includes a list of users and possible
 885  * roles on a course.
 886  *
 887  * @param moodle_recordset $rs The record set (may be false)
 888  * @param int $context ID of course context
 889  * @return array As described in groups_get_members_by_role
 890  */
 891 function groups_calculate_role_people($rs, $context) {
 892     global $CFG, $DB;
 893
 894     if (!$rs) {
 895         return array();
 896     }
 897
 898     $allroles = role_fix_names(get_all_roles($context), $context);
 899
 900     // Array of all involved roles
 901     $roles = array();
 902     // Array of all retrieved users
 903     $users = array();
 904     // Fill arrays
 905     foreach ($rs as $rec) {
 906         // Create information about user if this is a new one
 907         if (!array_key_exists($rec->userid, $users)) {
 908             // User data includes all the optional fields, but not any of the
 909             // stuff we added to get the role details
 910             $userdata = clone($rec);
 911             unset($userdata->roleid);
 912             unset($userdata->roleshortname);
 913             unset($userdata->rolename);
 914             unset($userdata->userid);
 915             $userdata->id = $rec->userid;
 916
 917             // Make an array to hold the list of roles for this user
 918             $userdata->roles = array();
 919             $users[$rec->userid] = $userdata;
 920         }
 921         // If user has a role...
 922         if (!is_null($rec->roleid)) {
 923             // Create information about role if this is a new one
 924             if (!array_key_exists($rec->roleid, $roles)) {
 925                 $role = $allroles[$rec->roleid];
 926                 $roledata = new stdClass();
 927                 $roledata->id        = $role->id;
 928                 $roledata->shortname = $role->shortname;
 929                 $roledata->name      = $role->localname;
 930                 $roledata->users = array();
 931                 $roles[$roledata->id] = $roledata;
 932             }
 933             // Record that user has role
 934             $users[$rec->userid]->roles[$rec->roleid] = $roles[$rec->roleid];
 935         }
 936     }
 937     $rs->close();
 938
 939     // Return false if there weren't any users
 940     if (count($users) == 0) {
 941         return false;
 942     }
 943
 944     // Add pseudo-role for multiple roles
 945     $roledata = new stdClass();
 946     $roledata->name = get_string('multipleroles','role');
 947     $roledata->users = array();
 948     $roles['*'] = $roledata;
 949
 950     $roledata = new stdClass();
 951     $roledata->name = get_string('noroles','role');
 952     $roledata->users = array();
 953     $roles[0] = $roledata;
 954
 955     // Now we rearrange the data to store users by role
 956     foreach ($users as $userid=>$userdata) {
 957         $rolecount = count($userdata->roles);
 958         if ($rolecount == 0) {
 959             // does not have any roles
 960             $roleid = 0;
 961         } else if($rolecount > 1) {
 962             $roleid = '*';
 963         } else {
 964             $userrole = reset($userdata->roles);
 965             $roleid = $userrole->id;
 966         }
 967         $roles[$roleid]->users[$userid] = $userdata;
 968     }
 969
 970     // Delete roles not used
 971     foreach ($roles as $key=>$roledata) {
 972         if (count($roledata->users)===0) {
 973             unset($roles[$key]);
 974         }
 975     }
 976
 977     // Return list of roles containing their users
 978     return $roles;
 979 }