enrol/locallib.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle is free software: you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation, either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 /**
  19  * This file contains the course_enrolment_manager class which is used to interface
  20  * with the functions that exist in enrollib.php in relation to a single course.
  21  *
  22  * @package    core
  23  * @subpackage enrol
  24  * @copyright  2010 Sam Hemelryk
  25  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  26  */
  27
  28 defined('MOODLE_INTERNAL') || die();
  29
  30 /**
  31  * This class provides a targeted tied together means of interfacing the enrolment
  32  * tasks together with a course.
  33  *
  34  * It is provided as a convenience more than anything else.
  35  *
  36  * @copyright 2010 Sam Hemelryk
  37  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  38  */
  39 class course_enrolment_manager {
  40
  41     /**
  42      * The course context
  43      * @var stdClass
  44      */
  45     protected $context;
  46     /**
  47      * The course we are managing enrolments for
  48      * @var stdClass
  49      */
  50     protected $course = null;
  51     /**
  52      * Limits the focus of the manager to one enrolment plugin instance
  53      * @var string
  54      */
  55     protected $instancefilter = null;
  56     /**
  57      * Limits the focus of the manager to users with specified role
  58      * @var int
  59      */
  60     protected $rolefilter = 0;
  61     /**
  62      * Limits the focus of the manager to users who match search string
  63      * @var string
  64      */
  65     protected $searchfilter = '';
  66
  67     /**
  68      * The total number of users enrolled in the course
  69      * Populated by course_enrolment_manager::get_total_users
  70      * @var int
  71      */
  72     protected $totalusers = null;
  73     /**
  74      * An array of users currently enrolled in the course
  75      * Populated by course_enrolment_manager::get_users
  76      * @var array
  77      */
  78     protected $users = array();
  79
  80     /**
  81      * An array of users who have roles within this course but who have not
  82      * been enrolled in the course
  83      * @var array
  84      */
  85     protected $otherusers = array();
  86
  87     /**
  88      * The total number of users who hold a role within the course but who
  89      * arn't enrolled.
  90      * @var int
  91      */
  92     protected $totalotherusers = null;
  93
  94     /**
  95      * The current moodle_page object
  96      * @var moodle_page
  97      */
  98     protected $moodlepage = null;
  99
 100     /**#@+
 101      * These variables are used to cache the information this class uses
 102      * please never use these directly instead use their get_ counterparts.
 103      * @access private
 104      * @var array
 105      */
 106     private $_instancessql = null;
 107     private $_instances = null;
 108     private $_inames = null;
 109     private $_plugins = null;
 110     private $_allplugins = null;
 111     private $_roles = null;
 112     private $_assignableroles = null;
 113     private $_assignablerolesothers = null;
 114     private $_groups = null;
 115     /**#@-*/
 116
 117     /**
 118      * Constructs the course enrolment manager
 119      *
 120      * @param moodle_page $moodlepage
 121      * @param stdClass $course
 122      * @param string $instancefilter
 123      * @param int $rolefilter If non-zero, filters to users with specified role
 124      * @param string $searchfilter If non-blank, filters to users with search text
 125      */
 126     public function __construct(moodle_page $moodlepage, $course, $instancefilter = null,
 127             $rolefilter = 0, $searchfilter = '') {
 128         $this->moodlepage = $moodlepage;
 129         $this->context = context_course::instance($course->id);
 130         $this->course = $course;
 131         $this->instancefilter = $instancefilter;
 132         $this->rolefilter = $rolefilter;
 133         $this->searchfilter = $searchfilter;
 134     }
 135
 136     /**
 137      * Returns the current moodle page
 138      * @return moodle_page
 139      */
 140     public function get_moodlepage() {
 141         return $this->moodlepage;
 142     }
 143
 144     /**
 145      * Returns the total number of enrolled users in the course.
 146      *
 147      * If a filter was specificed this will be the total number of users enrolled
 148      * in this course by means of that instance.
 149      *
 150      * @global moodle_database $DB
 151      * @return int
 152      */
 153     public function get_total_users() {
 154         global $DB;
 155         if ($this->totalusers === null) {
 156             list($instancessql, $params, $filter) = $this->get_instance_sql();
 157             list($filtersql, $moreparams) = $this->get_filter_sql();
 158             $params += $moreparams;
 159             $sqltotal = "SELECT COUNT(DISTINCT u.id)
 160                            FROM {user} u
 161                            JOIN {user_enrolments} ue ON (ue.userid = u.id  AND ue.enrolid $instancessql)
 162                            JOIN {enrol} e ON (e.id = ue.enrolid)
 163                           WHERE $filtersql";
 164             $this->totalusers = (int)$DB->count_records_sql($sqltotal, $params);
 165         }
 166         return $this->totalusers;
 167     }
 168
 169     /**
 170      * Returns the total number of enrolled users in the course.
 171      *
 172      * If a filter was specificed this will be the total number of users enrolled
 173      * in this course by means of that instance.
 174      *
 175      * @global moodle_database $DB
 176      * @return int
 177      */
 178     public function get_total_other_users() {
 179         global $DB;
 180         if ($this->totalotherusers === null) {
 181             list($ctxcondition, $params) = $DB->get_in_or_equal(get_parent_contexts($this->context, true), SQL_PARAMS_NAMED, 'ctx');
 182             $params['courseid'] = $this->course->id;
 183             $sql = "SELECT COUNT(DISTINCT u.id)
 184                       FROM {role_assignments} ra
 185                       JOIN {user} u ON u.id = ra.userid
 186                       JOIN {context} ctx ON ra.contextid = ctx.id
 187                  LEFT JOIN (
 188                            SELECT ue.id, ue.userid
 189                              FROM {user_enrolments} ue
 190                         LEFT JOIN {enrol} e ON e.id=ue.enrolid
 191                             WHERE e.courseid = :courseid
 192                          ) ue ON ue.userid=u.id
 193                      WHERE ctx.id $ctxcondition AND
 194                            ue.id IS NULL";
 195             $this->totalotherusers = (int)$DB->count_records_sql($sql, $params);
 196         }
 197         return $this->totalotherusers;
 198     }
 199
 200     /**
 201      * Gets all of the users enrolled in this course.
 202      *
 203      * If a filter was specified this will be the users who were enrolled
 204      * in this course by means of that instance. If role or search filters were
 205      * specified then these will also be applied.
 206      *
 207      * @global moodle_database $DB
 208      * @param string $sort
 209      * @param string $direction ASC or DESC
 210      * @param int $page First page should be 0
 211      * @param int $perpage Defaults to 25
 212      * @return array
 213      */
 214     public function get_users($sort, $direction='ASC', $page=0, $perpage=25) {
 215         global $DB;
 216         if ($direction !== 'ASC') {
 217             $direction = 'DESC';
 218         }
 219         $key = md5("$sort-$direction-$page-$perpage");
 220         if (!array_key_exists($key, $this->users)) {
 221             list($instancessql, $params, $filter) = $this->get_instance_sql();
 222             list($filtersql, $moreparams) = $this->get_filter_sql();
 223             $params += $moreparams;
 224             $extrafields = get_extra_user_fields($this->get_context());
 225             $extrafields[] = 'lastaccess';
 226             $ufields = user_picture::fields('u', $extrafields);
 227             $sql = "SELECT DISTINCT $ufields, ul.timeaccess AS lastseen
 228                       FROM {user} u
 229                       JOIN {user_enrolments} ue ON (ue.userid = u.id  AND ue.enrolid $instancessql)
 230                       JOIN {enrol} e ON (e.id = ue.enrolid)
 231                  LEFT JOIN {user_lastaccess} ul ON (ul.courseid = e.courseid AND ul.userid = u.id)
 232                      WHERE $filtersql";
 233             if ($sort === 'firstname') {
 234                 $sql .= " ORDER BY u.firstname $direction, u.lastname $direction";
 235             } else if ($sort === 'lastname') {
 236                 $sql .= " ORDER BY u.lastname $direction, u.firstname $direction";
 237             } else if ($sort === 'email') {
 238                 $sql .= " ORDER BY u.email $direction, u.lastname $direction, u.firstname $direction";
 239             } else if ($sort === 'lastseen') {
 240                 $sql .= " ORDER BY ul.timeaccess $direction, u.lastname $direction, u.firstname $direction";
 241             }
 242             $this->users[$key] = $DB->get_records_sql($sql, $params, $page*$perpage, $perpage);
 243         }
 244         return $this->users[$key];
 245     }
 246
 247     /**
 248      * Obtains WHERE clause to filter results by defined search and role filter
 249      * (instance filter is handled separately in JOIN clause, see
 250      * get_instance_sql).
 251      *
 252      * @return array Two-element array with SQL and params for WHERE clause
 253      */
 254     protected function get_filter_sql() {
 255         global $DB;
 256
 257         // Search condition.
 258         $extrafields = get_extra_user_fields($this->get_context());
 259         list($sql, $params) = users_search_sql($this->searchfilter, 'u', true, $extrafields);
 260
 261         // Role condition.
 262         if ($this->rolefilter) {
 263             // Get context SQL.
 264             $contextids = $this->context->get_parent_context_ids();
 265             $contextids[] = $this->context->id;
 266             list($contextsql, $contextparams) = $DB->get_in_or_equal($contextids, SQL_PARAMS_NAMED);
 267             $params += $contextparams;
 268
 269             // Role check condition.
 270             $sql .= " AND (SELECT COUNT(1) FROM {role_assignments} ra WHERE ra.userid = u.id " .
 271                     "AND ra.roleid = :roleid AND ra.contextid $contextsql) > 0";
 272             $params['roleid'] = $this->rolefilter;
 273         }
 274
 275         return array($sql, $params);
 276     }
 277
 278     /**
 279      * Gets and array of other users.
 280      *
 281      * Other users are users who have been assigned roles or inherited roles
 282      * within this course but who have not been enrolled in the course
 283      *
 284      * @global moodle_database $DB
 285      * @param string $sort
 286      * @param string $direction
 287      * @param int $page
 288      * @param int $perpage
 289      * @return array
 290      */
 291     public function get_other_users($sort, $direction='ASC', $page=0, $perpage=25) {
 292         global $DB;
 293         if ($direction !== 'ASC') {
 294             $direction = 'DESC';
 295         }
 296         $key = md5("$sort-$direction-$page-$perpage");
 297         if (!array_key_exists($key, $this->otherusers)) {
 298             list($ctxcondition, $params) = $DB->get_in_or_equal(get_parent_contexts($this->context, true), SQL_PARAMS_NAMED, 'ctx');
 299             $params['courseid'] = $this->course->id;
 300             $params['cid'] = $this->course->id;
 301             $sql = "SELECT ra.id as raid, ra.contextid, ra.component, ctx.contextlevel, ra.roleid, u.*, ue.lastseen
 302                     FROM {role_assignments} ra
 303                     JOIN {user} u ON u.id = ra.userid
 304                     JOIN {context} ctx ON ra.contextid = ctx.id
 305                LEFT JOIN (
 306                        SELECT ue.id, ue.userid, ul.timeaccess AS lastseen
 307                          FROM {user_enrolments} ue
 308                     LEFT JOIN {enrol} e ON e.id=ue.enrolid
 309                     LEFT JOIN {user_lastaccess} ul ON (ul.courseid = e.courseid AND ul.userid = ue.userid)
 310                         WHERE e.courseid = :courseid
 311                        ) ue ON ue.userid=u.id
 312                    WHERE ctx.id $ctxcondition AND
 313                          ue.id IS NULL
 314                 ORDER BY u.$sort $direction, ctx.depth DESC";
 315             $this->otherusers[$key] = $DB->get_records_sql($sql, $params, $page*$perpage, $perpage);
 316         }
 317         return $this->otherusers[$key];
 318     }
 319
 320     /**
 321      * Helper method used by {@link get_potential_users()} and {@link search_other_users()}.
 322      *
 323      * @param string $search the search term, if any.
 324      * @param bool $searchanywhere Can the search term be anywhere, or must it be at the start.
 325      * @return array with three elements:
 326      *     string list of fields to SELECT,
 327      *     string contents of SQL WHERE clause,
 328      *     array query params. Note that the SQL snippets use named parameters.
 329      */
 330     protected function get_basic_search_conditions($search, $searchanywhere) {
 331         global $DB, $CFG;
 332
 333         // Add some additional sensible conditions
 334         $tests = array("u.id <> :guestid", 'u.deleted = 0', 'u.confirmed = 1');
 335         $params = array('guestid' => $CFG->siteguest);
 336         if (!empty($search)) {
 337             $conditions = get_extra_user_fields($this->get_context());
 338             $conditions[] = 'u.firstname';
 339             $conditions[] = 'u.lastname';
 340             $conditions[] = $DB->sql_fullname('u.firstname', 'u.lastname');
 341             if ($searchanywhere) {
 342                 $searchparam = '%' . $search . '%';
 343             } else {
 344                 $searchparam = $search . '%';
 345             }
 346             $i = 0;
 347             foreach ($conditions as $key => $condition) {
 348                 $conditions[$key] = $DB->sql_like($condition, ":con{$i}00", false);
 349                 $params["con{$i}00"] = $searchparam;
 350                 $i++;
 351             }
 352             $tests[] = '(' . implode(' OR ', $conditions) . ')';
 353         }
 354         $wherecondition = implode(' AND ', $tests);
 355
 356         $extrafields = get_extra_user_fields($this->get_context(), array('username', 'lastaccess'));
 357         $extrafields[] = 'username';
 358         $extrafields[] = 'lastaccess';
 359         $ufields = user_picture::fields('u', $extrafields);
 360
 361         return array($ufields, $params, $wherecondition);
 362     }
 363
 364     /**
 365      * Helper method used by {@link get_potential_users()} and {@link search_other_users()}.
 366      *
 367      * @param string $search the search string, if any.
 368      * @param string $fields the first bit of the SQL when returning some users.
 369      * @param string $countfields fhe first bit of the SQL when counting the users.
 370      * @param string $sql the bulk of the SQL statement.
 371      * @param array $params query parameters.
 372      * @param int $page which page number of the results to show.
 373      * @param int $perpage number of users per page.
 374      * @param int $addedenrollment number of users added to enrollment.
 375      * @return array with two elememts:
 376      *      int total number of users matching the search.
 377      *      array of user objects returned by the query.
 378      */
 379     protected function execute_search_queries($search, $fields, $countfields, $sql, array $params, $page, $perpage, $addedenrollment=0) {
 380         global $DB, $CFG;
 381
 382         list($sort, $sortparams) = users_order_by_sql('u', $search, $this->get_context());
 383         $order = ' ORDER BY ' . $sort;
 384
 385         $totalusers = $DB->count_records_sql($countfields . $sql, $params);
 386         $availableusers = $DB->get_records_sql($fields . $sql . $order,
 387                 array_merge($params, $sortparams), ($page*$perpage) - $addedenrollment, $perpage);
 388
 389         return array('totalusers' => $totalusers, 'users' => $availableusers);
 390     }
 391
 392     /**
 393      * Gets an array of the users that can be enrolled in this course.
 394      *
 395      * @global moodle_database $DB
 396      * @param int $enrolid
 397      * @param string $search
 398      * @param bool $searchanywhere
 399      * @param int $page Defaults to 0
 400      * @param int $perpage Defaults to 25
 401      * @param int $addedenrollment Defaults to 0
 402      * @return array Array(totalusers => int, users => array)
 403      */
 404     public function get_potential_users($enrolid, $search='', $searchanywhere=false, $page=0, $perpage=25, $addedenrollment=0) {
 405         global $DB;
 406
 407         list($ufields, $params, $wherecondition) = $this->get_basic_search_conditions($search, $searchanywhere);
 408
 409         $fields      = 'SELECT '.$ufields;
 410         $countfields = 'SELECT COUNT(1)';
 411         $sql = " FROM {user} u
 412             LEFT JOIN {user_enrolments} ue ON (ue.userid = u.id AND ue.enrolid = :enrolid)
 413                 WHERE $wherecondition
 414                       AND ue.id IS NULL";
 415         $params['enrolid'] = $enrolid;
 416
 417         return $this->execute_search_queries($search, $fields, $countfields, $sql, $params, $page, $perpage, $addedenrollment);
 418     }
 419
 420     /**
 421      * Searches other users and returns paginated results
 422      *
 423      * @global moodle_database $DB
 424      * @param string $search
 425      * @param bool $searchanywhere
 426      * @param int $page Starting at 0
 427      * @param int $perpage
 428      * @return array
 429      */
 430     public function search_other_users($search='', $searchanywhere=false, $page=0, $perpage=25) {
 431         global $DB, $CFG;
 432
 433         list($ufields, $params, $wherecondition) = $this->get_basic_search_conditions($search, $searchanywhere);
 434
 435         $fields      = 'SELECT ' . $ufields;
 436         $countfields = 'SELECT COUNT(u.id)';
 437         $sql   = " FROM {user} u
 438               LEFT JOIN {role_assignments} ra ON (ra.userid = u.id AND ra.contextid = :contextid)
 439                   WHERE $wherecondition
 440                     AND ra.id IS NULL";
 441         $params['contextid'] = $this->context->id;
 442
 443         return $this->execute_search_queries($search, $fields, $countfields, $sql, $params, $page, $perpage);
 444     }
 445
 446     /**
 447      * Gets an array containing some SQL to user for when selecting, params for
 448      * that SQL, and the filter that was used in constructing the sql.
 449      *
 450      * @global moodle_database $DB
 451      * @return string
 452      */
 453     protected function get_instance_sql() {
 454         global $DB;
 455         if ($this->_instancessql === null) {
 456             $instances = $this->get_enrolment_instances();
 457             $filter = $this->get_enrolment_filter();
 458             if ($filter && array_key_exists($filter, $instances)) {
 459                 $sql = " = :ifilter";
 460                 $params = array('ifilter'=>$filter);
 461             } else {
 462                 $filter = 0;
 463                 if ($instances) {
 464                     list($sql, $params) = $DB->get_in_or_equal(array_keys($this->get_enrolment_instances()), SQL_PARAMS_NAMED);
 465                 } else {
 466                     // no enabled instances, oops, we should probably say something
 467                     $sql = "= :never";
 468                     $params = array('never'=>-1);
 469                 }
 470             }
 471             $this->instancefilter = $filter;
 472             $this->_instancessql = array($sql, $params, $filter);
 473         }
 474         return $this->_instancessql;
 475     }
 476
 477     /**
 478      * Returns all of the enrolment instances for this course.
 479      *
 480      * NOTE: since 2.4 it includes instances of disabled plugins too.
 481      *
 482      * @return array
 483      */
 484     public function get_enrolment_instances() {
 485         if ($this->_instances === null) {
 486             $this->_instances = enrol_get_instances($this->course->id, false);
 487         }
 488         return $this->_instances;
 489     }
 490
 491     /**
 492      * Returns the names for all of the enrolment instances for this course.
 493      *
 494      * NOTE: since 2.4 it includes instances of disabled plugins too.
 495      *
 496      * @return array
 497      */
 498     public function get_enrolment_instance_names() {
 499         if ($this->_inames === null) {
 500             $instances = $this->get_enrolment_instances();
 501             $plugins = $this->get_enrolment_plugins(false);
 502             foreach ($instances as $key=>$instance) {
 503                 if (!isset($plugins[$instance->enrol])) {
 504                     // weird, some broken stuff in plugin
 505                     unset($instances[$key]);
 506                     continue;
 507                 }
 508                 $this->_inames[$key] = $plugins[$instance->enrol]->get_instance_name($instance);
 509             }
 510         }
 511         return $this->_inames;
 512     }
 513
 514     /**
 515      * Gets all of the enrolment plugins that are active for this course.
 516      *
 517      * @param bool $onlyenabled return only enabled enrol plugins
 518      * @return array
 519      */
 520     public function get_enrolment_plugins($onlyenabled = true) {
 521         if ($this->_plugins === null) {
 522             $this->_plugins = enrol_get_plugins(true);
 523         }
 524
 525         if ($onlyenabled) {
 526             return $this->_plugins;
 527         }
 528
 529         if ($this->_allplugins === null) {
 530             // Make sure we have the same objects in _allplugins and _plugins.
 531             $this->_allplugins = $this->_plugins;
 532             foreach (enrol_get_plugins(false) as $name=>$plugin) {
 533                 if (!isset($this->_allplugins[$name])) {
 534                     $this->_allplugins[$name] = $plugin;
 535                 }
 536             }
 537         }
 538
 539         return $this->_allplugins;
 540     }
 541
 542     /**
 543      * Gets all of the roles this course can contain.
 544      *
 545      * @return array
 546      */
 547     public function get_all_roles() {
 548         if ($this->_roles === null) {
 549             $this->_roles = role_fix_names(get_all_roles($this->context), $this->context);
 550         }
 551         return $this->_roles;
 552     }
 553
 554     /**
 555      * Gets all of the assignable roles for this course.
 556      *
 557      * @return array
 558      */
 559     public function get_assignable_roles($otherusers = false) {
 560         if ($this->_assignableroles === null) {
 561             $this->_assignableroles = get_assignable_roles($this->context, ROLENAME_ALIAS, false); // verifies unassign access control too
 562         }
 563
 564         if ($otherusers) {
 565             if (!is_array($this->_assignablerolesothers)) {
 566                 $this->_assignablerolesothers = array();
 567                 list($courseviewroles, $ignored) = get_roles_with_cap_in_context($this->context, 'moodle/course:view');
 568                 foreach ($this->_assignableroles as $roleid=>$role) {
 569                     if (isset($courseviewroles[$roleid])) {
 570                         $this->_assignablerolesothers[$roleid] = $role;
 571                     }
 572                 }
 573             }
 574             return $this->_assignablerolesothers;
 575         } else {
 576             return $this->_assignableroles;
 577         }
 578     }
 579
 580     /**
 581      * Gets all of the groups for this course.
 582      *
 583      * @return array
 584      */
 585     public function get_all_groups() {
 586         if ($this->_groups === null) {
 587             $this->_groups = groups_get_all_groups($this->course->id);
 588             foreach ($this->_groups as $gid=>$group) {
 589                 $this->_groups[$gid]->name = format_string($group->name);
 590             }
 591         }
 592         return $this->_groups;
 593     }
 594
 595     /**
 596      * Unenrols a user from the course given the users ue entry
 597      *
 598      * @global moodle_database $DB
 599      * @param stdClass $ue
 600      * @return bool
 601      */
 602     public function unenrol_user($ue) {
 603         global $DB;
 604         list ($instance, $plugin) = $this->get_user_enrolment_components($ue);
 605         if ($instance && $plugin && $plugin->allow_unenrol_user($instance, $ue) && has_capability("enrol/$instance->enrol:unenrol", $this->context)) {
 606             $plugin->unenrol_user($instance, $ue->userid);
 607             return true;
 608         }
 609         return false;
 610     }
 611
 612     /**
 613      * Given a user enrolment record this method returns the plugin and enrolment
 614      * instance that relate to it.
 615      *
 616      * @param stdClass|int $userenrolment
 617      * @return array array($instance, $plugin)
 618      */
 619     public function get_user_enrolment_components($userenrolment) {
 620         global $DB;
 621         if (is_numeric($userenrolment)) {
 622             $userenrolment = $DB->get_record('user_enrolments', array('id'=>(int)$userenrolment));
 623         }
 624         $instances = $this->get_enrolment_instances();
 625         $plugins = $this->get_enrolment_plugins(false);
 626         if (!$userenrolment || !isset($instances[$userenrolment->enrolid])) {
 627             return array(false, false);
 628         }
 629         $instance = $instances[$userenrolment->enrolid];
 630         $plugin = $plugins[$instance->enrol];
 631         return array($instance, $plugin);
 632     }
 633
 634     /**
 635      * Removes an assigned role from a user.
 636      *
 637      * @global moodle_database $DB
 638      * @param int $userid
 639      * @param int $roleid
 640      * @return bool
 641      */
 642     public function unassign_role_from_user($userid, $roleid) {
 643         global $DB;
 644         // Admins may unassign any role, others only those they could assign.
 645         if (!is_siteadmin() and !array_key_exists($roleid, $this->get_assignable_roles())) {
 646             if (defined('AJAX_SCRIPT')) {
 647                 throw new moodle_exception('invalidrole');
 648             }
 649             return false;
 650         }
 651         $user = $DB->get_record('user', array('id'=>$userid), '*', MUST_EXIST);
 652         $ras = $DB->get_records('role_assignments', array('contextid'=>$this->context->id, 'userid'=>$user->id, 'roleid'=>$roleid));
 653         foreach ($ras as $ra) {
 654             if ($ra->component) {
 655                 if (strpos($ra->component, 'enrol_') !== 0) {
 656                     continue;
 657                 }
 658                 if (!$plugin = enrol_get_plugin(substr($ra->component, 6))) {
 659                     continue;
 660                 }
 661                 if ($plugin->roles_protected()) {
 662                     continue;
 663                 }
 664             }
 665             role_unassign($ra->roleid, $ra->userid, $ra->contextid, $ra->component, $ra->itemid);
 666         }
 667         return true;
 668     }
 669
 670     /**
 671      * Assigns a role to a user.
 672      *
 673      * @param int $roleid
 674      * @param int $userid
 675      * @return int|false
 676      */
 677     public function assign_role_to_user($roleid, $userid) {
 678         require_capability('moodle/role:assign', $this->context);
 679         if (!array_key_exists($roleid, $this->get_assignable_roles())) {
 680             if (defined('AJAX_SCRIPT')) {
 681                 throw new moodle_exception('invalidrole');
 682             }
 683             return false;
 684         }
 685         return role_assign($roleid, $userid, $this->context->id, '', NULL);
 686     }
 687
 688     /**
 689      * Adds a user to a group
 690      *
 691      * @param stdClass $user
 692      * @param int $groupid
 693      * @return bool
 694      */
 695     public function add_user_to_group($user, $groupid) {
 696         require_capability('moodle/course:managegroups', $this->context);
 697         $group = $this->get_group($groupid);
 698         if (!$group) {
 699             return false;
 700         }
 701         return groups_add_member($group->id, $user->id);
 702     }
 703
 704     /**
 705      * Removes a user from a group
 706      *
 707      * @global moodle_database $DB
 708      * @param StdClass $user
 709      * @param int $groupid
 710      * @return bool
 711      */
 712     public function remove_user_from_group($user, $groupid) {
 713         global $DB;
 714         require_capability('moodle/course:managegroups', $this->context);
 715         $group = $this->get_group($groupid);
 716         if (!groups_remove_member_allowed($group, $user)) {
 717             return false;
 718         }
 719         if (!$group) {
 720             return false;
 721         }
 722         return groups_remove_member($group, $user);
 723     }
 724
 725     /**
 726      * Gets the requested group
 727      *
 728      * @param int $groupid
 729      * @return stdClass|int
 730      */
 731     public function get_group($groupid) {
 732         $groups = $this->get_all_groups();
 733         if (!array_key_exists($groupid, $groups)) {
 734             return false;
 735         }
 736         return $groups[$groupid];
 737     }
 738
 739     /**
 740      * Edits an enrolment
 741      *
 742      * @param stdClass $userenrolment
 743      * @param stdClass $data
 744      * @return bool
 745      */
 746     public function edit_enrolment($userenrolment, $data) {
 747         //Only allow editing if the user has the appropriate capability
 748         //Already checked in /enrol/users.php but checking again in case this function is called from elsewhere
 749         list($instance, $plugin) = $this->get_user_enrolment_components($userenrolment);
 750         if ($instance && $plugin && $plugin->allow_manage($instance) && has_capability("enrol/$instance->enrol:manage", $this->context)) {
 751             if (!isset($data->status)) {
 752                 $data->status = $userenrolment->status;
 753             }
 754             $plugin->update_user_enrol($instance, $userenrolment->userid, $data->status, $data->timestart, $data->timeend);
 755             return true;
 756         }
 757         return false;
 758     }
 759
 760     /**
 761      * Returns the current enrolment filter that is being applied by this class
 762      * @return string
 763      */
 764     public function get_enrolment_filter() {
 765         return $this->instancefilter;
 766     }
 767
 768     /**
 769      * Gets the roles assigned to this user that are applicable for this course.
 770      *
 771      * @param int $userid
 772      * @return array
 773      */
 774     public function get_user_roles($userid) {
 775         $roles = array();
 776         $ras = get_user_roles($this->context, $userid, true, 'c.contextlevel DESC, r.sortorder ASC');
 777         $plugins = $this->get_enrolment_plugins(false);
 778         foreach ($ras as $ra) {
 779             if ($ra->contextid != $this->context->id) {
 780                 if (!array_key_exists($ra->roleid, $roles)) {
 781                     $roles[$ra->roleid] = null;
 782                 }
 783                 // higher ras, course always takes precedence
 784                 continue;
 785             }
 786             if (array_key_exists($ra->roleid, $roles) && $roles[$ra->roleid] === false) {
 787                 continue;
 788             }
 789             $changeable = true;
 790             if ($ra->component) {
 791                 $changeable = false;
 792                 if (strpos($ra->component, 'enrol_') === 0) {
 793                     $plugin = substr($ra->component, 6);
 794                     if (isset($plugins[$plugin])) {
 795                         $changeable = !$plugins[$plugin]->roles_protected();
 796                     }
 797                 }
 798             }
 799
 800             $roles[$ra->roleid] = $changeable;
 801         }
 802         return $roles;
 803     }
 804
 805     /**
 806      * Gets the enrolments this user has in the course - including all suspended plugins and instances.
 807      *
 808      * @global moodle_database $DB
 809      * @param int $userid
 810      * @return array
 811      */
 812     public function get_user_enrolments($userid) {
 813         global $DB;
 814         list($instancessql, $params, $filter) = $this->get_instance_sql();
 815         $params['userid'] = $userid;
 816         $userenrolments = $DB->get_records_select('user_enrolments', "enrolid $instancessql AND userid = :userid", $params);
 817         $instances = $this->get_enrolment_instances();
 818         $plugins = $this->get_enrolment_plugins(false);
 819         $inames = $this->get_enrolment_instance_names();
 820         foreach ($userenrolments as &$ue) {
 821             $ue->enrolmentinstance     = $instances[$ue->enrolid];
 822             $ue->enrolmentplugin       = $plugins[$ue->enrolmentinstance->enrol];
 823             $ue->enrolmentinstancename = $inames[$ue->enrolmentinstance->id];
 824         }
 825         return $userenrolments;
 826     }
 827
 828     /**
 829      * Gets the groups this user belongs to
 830      *
 831      * @param int $userid
 832      * @return array
 833      */
 834     public function get_user_groups($userid) {
 835         return groups_get_all_groups($this->course->id, $userid, 0, 'g.id');
 836     }
 837
 838     /**
 839      * Retursn an array of params that would go into the URL to return to this
 840      * exact page.
 841      *
 842      * @return array
 843      */
 844     public function get_url_params() {
 845         $args = array(
 846             'id' => $this->course->id
 847         );
 848         if (!empty($this->instancefilter)) {
 849             $args['ifilter'] = $this->instancefilter;
 850         }
 851         if (!empty($this->rolefilter)) {
 852             $args['role'] = $this->rolefilter;
 853         }
 854         if ($this->searchfilter !== '') {
 855             $args['search'] = $this->searchfilter;
 856         }
 857         return $args;
 858     }
 859
 860     /**
 861      * Returns the course this object is managing enrolments for
 862      *
 863      * @return stdClass
 864      */
 865     public function get_course() {
 866         return $this->course;
 867     }
 868
 869     /**
 870      * Returns the course context
 871      *
 872      * @return stdClass
 873      */
 874     public function get_context() {
 875         return $this->context;
 876     }
 877
 878     /**
 879      * Gets an array of other users in this course ready for display.
 880      *
 881      * Other users are users who have been assigned or inherited roles within this
 882      * course but have not been enrolled.
 883      *
 884      * @param core_enrol_renderer $renderer
 885      * @param moodle_url $pageurl
 886      * @param string $sort
 887      * @param string $direction ASC | DESC
 888      * @param int $page Starting from 0
 889      * @param int $perpage
 890      * @return array
 891      */
 892     public function get_other_users_for_display(core_enrol_renderer $renderer, moodle_url $pageurl, $sort, $direction, $page, $perpage) {
 893
 894         $userroles = $this->get_other_users($sort, $direction, $page, $perpage);
 895         $roles = $this->get_all_roles();
 896         $plugins = $this->get_enrolment_plugins(false);
 897
 898         $context    = $this->get_context();
 899         $now = time();
 900         $extrafields = get_extra_user_fields($context);
 901
 902         $users = array();
 903         foreach ($userroles as $userrole) {
 904             $contextid = $userrole->contextid;
 905             unset($userrole->contextid); // This would collide with user avatar.
 906             if (!array_key_exists($userrole->id, $users)) {
 907                 $users[$userrole->id] = $this->prepare_user_for_display($userrole, $extrafields, $now);
 908             }
 909             $a = new stdClass;
 910             $a->role = $roles[$userrole->roleid]->localname;
 911             if ($contextid == $this->context->id) {
 912                 $changeable = true;
 913                 if ($userrole->component) {
 914                     $changeable = false;
 915                     if (strpos($userrole->component, 'enrol_') === 0) {
 916                         $plugin = substr($userrole->component, 6);
 917                         if (isset($plugins[$plugin])) {
 918                             $changeable = !$plugin[$plugin]->roles_protected();
 919                         }
 920                     }
 921                 }
 922                 $roletext = get_string('rolefromthiscourse', 'enrol', $a);
 923             } else {
 924                 $changeable = false;
 925                 switch ($userrole->contextlevel) {
 926                     case CONTEXT_COURSE :
 927                         // Meta course
 928                         $roletext = get_string('rolefrommetacourse', 'enrol', $a);
 929                         break;
 930                     case CONTEXT_COURSECAT :
 931                         $roletext = get_string('rolefromcategory', 'enrol', $a);
 932                         break;
 933                     case CONTEXT_SYSTEM:
 934                     default:
 935                         $roletext = get_string('rolefromsystem', 'enrol', $a);
 936                         break;
 937                 }
 938             }
 939             if (!isset($users[$userrole->id]['roles'])) {
 940                 $users[$userrole->id]['roles'] = array();
 941             }
 942             $users[$userrole->id]['roles'][$userrole->roleid] = array(
 943                 'text' => $roletext,
 944                 'unchangeable' => !$changeable
 945             );
 946         }
 947         return $users;
 948     }
 949
 950     /**
 951      * Gets an array of users for display, this includes minimal user information
 952      * as well as minimal information on the users roles, groups, and enrolments.
 953      *
 954      * @param core_enrol_renderer $renderer
 955      * @param moodle_url $pageurl
 956      * @param int $sort
 957      * @param string $direction ASC or DESC
 958      * @param int $page
 959      * @param int $perpage
 960      * @return array
 961      */
 962     public function get_users_for_display(course_enrolment_manager $manager, $sort, $direction, $page, $perpage) {
 963         $pageurl = $manager->get_moodlepage()->url;
 964         $users = $this->get_users($sort, $direction, $page, $perpage);
 965
 966         $now = time();
 967         $straddgroup = get_string('addgroup', 'group');
 968         $strunenrol = get_string('unenrol', 'enrol');
 969         $stredit = get_string('edit');
 970
 971         $allroles   = $this->get_all_roles();
 972         $assignable = $this->get_assignable_roles();
 973         $allgroups  = $this->get_all_groups();
 974         $context    = $this->get_context();
 975         $canmanagegroups = has_capability('moodle/course:managegroups', $context);
 976
 977         $url = new moodle_url($pageurl, $this->get_url_params());
 978         $extrafields = get_extra_user_fields($context);
 979
 980         $enabledplugins = $this->get_enrolment_plugins(true);
 981
 982         $userdetails = array();
 983         foreach ($users as $user) {
 984             $details = $this->prepare_user_for_display($user, $extrafields, $now);
 985
 986             // Roles
 987             $details['roles'] = array();
 988             foreach ($this->get_user_roles($user->id) as $rid=>$rassignable) {
 989                 $unchangeable = !$rassignable;
 990                 if (!is_siteadmin() and !isset($assignable[$rid])) {
 991                     $unchangeable = true;
 992                 }
 993                 $details['roles'][$rid] = array('text'=>$allroles[$rid]->localname, 'unchangeable'=>$unchangeable);
 994             }
 995
 996             // Users
 997             $usergroups = $this->get_user_groups($user->id);
 998             $details['groups'] = array();
 999             foreach($usergroups as $gid=>$unused) {
1000                 $details['groups'][$gid] = $allgroups[$gid]->name;
1001             }
1002
1003             // Enrolments
1004             $details['enrolments'] = array();
1005             foreach ($this->get_user_enrolments($user->id) as $ue) {
1006                 if (!isset($enabledplugins[$ue->enrolmentinstance->enrol])) {
1007                     $details['enrolments'][$ue->id] = array(
1008                         'text' => $ue->enrolmentinstancename,
1009                         'period' => null,
1010                         'dimmed' =>  true,
1011                         'actions' => array()
1012                     );
1013                     continue;
1014                 } else if ($ue->timestart and $ue->timeend) {
1015                     $period = get_string('periodstartend', 'enrol', array('start'=>userdate($ue->timestart), 'end'=>userdate($ue->timeend)));
1016                     $periodoutside = ($ue->timestart && $ue->timeend && $now < $ue->timestart && $now > $ue->timeend);
1017                 } else if ($ue->timestart) {
1018                     $period = get_string('periodstart', 'enrol', userdate($ue->timestart));
1019                     $periodoutside = ($ue->timestart && $now < $ue->timestart);
1020                 } else if ($ue->timeend) {
1021                     $period = get_string('periodend', 'enrol', userdate($ue->timeend));
1022                     $periodoutside = ($ue->timeend && $now > $ue->timeend);
1023                 } else {
1024                     // If there is no start or end show when user was enrolled.
1025                     $period = get_string('periodnone', 'enrol', userdate($ue->timecreated));
1026                     $periodoutside = false;
1027                 }
1028                 $details['enrolments'][$ue->id] = array(
1029                     'text' => $ue->enrolmentinstancename,
1030                     'period' => $period,
1031                     'dimmed' =>  ($periodoutside or $ue->status != ENROL_USER_ACTIVE or $ue->enrolmentinstance->status != ENROL_INSTANCE_ENABLED),
1032                     'actions' => $ue->enrolmentplugin->get_user_enrolment_actions($manager, $ue)
1033                 );
1034             }
1035             $userdetails[$user->id] = $details;
1036         }
1037         return $userdetails;
1038     }
1039
1040     /**
1041      * Prepare a user record for display
1042      *
1043      * This function is called by both {@link get_users_for_display} and {@link get_other_users_for_display} to correctly
1044      * prepare user fields for display
1045      *
1046      * Please note that this function does not check capability for moodle/coures:viewhiddenuserfields
1047      *
1048      * @param object $user The user record
1049      * @param array $extrafields The list of fields as returned from get_extra_user_fields used to determine which
1050      * additional fields may be displayed
1051      * @param int $now The time used for lastaccess calculation
1052      * @return array The fields to be displayed including userid, courseid, picture, firstname, lastseen and any
1053      * additional fields from $extrafields
1054      */
1055     private function prepare_user_for_display($user, $extrafields, $now) {
1056         $details = array(
1057             'userid'    => $user->id,
1058             'courseid'  => $this->get_course()->id,
1059             'picture'   => new user_picture($user),
1060             'firstname' => fullname($user, has_capability('moodle/site:viewfullnames', $this->get_context())),
1061             'lastseen'  => get_string('never'),
1062         );
1063         foreach ($extrafields as $field) {
1064             $details[$field] = $user->{$field};
1065         }
1066
1067         if ($user->lastaccess) {
1068             $details['lastseen'] = format_time($now - $user->lastaccess);
1069         }
1070         return $details;
1071     }
1072
1073     public function get_manual_enrol_buttons() {
1074         $plugins = $this->get_enrolment_plugins(true); // Skip disabled plugins.
1075         $buttons = array();
1076         foreach ($plugins as $plugin) {
1077             $newbutton = $plugin->get_manual_enrol_button($this);
1078             if (is_array($newbutton)) {
1079                 $buttons += $newbutton;
1080             } else if ($newbutton instanceof enrol_user_button) {
1081                 $buttons[] = $newbutton;
1082             }
1083         }
1084         return $buttons;
1085     }
1086
1087     public function has_instance($enrolpluginname) {
1088         // Make sure manual enrolments instance exists
1089         foreach ($this->get_enrolment_instances() as $instance) {
1090             if ($instance->enrol == $enrolpluginname) {
1091                 return true;
1092             }
1093         }
1094         return false;
1095     }
1096
1097     /**
1098      * Returns the enrolment plugin that the course manager was being filtered to.
1099      *
1100      * If no filter was being applied then this function returns false.
1101      *
1102      * @return enrol_plugin
1103      */
1104     public function get_filtered_enrolment_plugin() {
1105         $instances = $this->get_enrolment_instances();
1106         $plugins = $this->get_enrolment_plugins(false);
1107
1108         if (empty($this->instancefilter) || !array_key_exists($this->instancefilter, $instances)) {
1109             return false;
1110         }
1111
1112         $instance = $instances[$this->instancefilter];
1113         return $plugins[$instance->enrol];
1114     }
1115
1116     /**
1117      * Returns and array of users + enrolment details.
1118      *
1119      * Given an array of user id's this function returns and array of user enrolments for those users
1120      * as well as enough user information to display the users name and picture for each enrolment.
1121      *
1122      * @global moodle_database $DB
1123      * @param array $userids
1124      * @return array
1125      */
1126     public function get_users_enrolments(array $userids) {
1127         global $DB;
1128
1129         $instances = $this->get_enrolment_instances();
1130         $plugins = $this->get_enrolment_plugins(false);
1131
1132         if  (!empty($this->instancefilter)) {
1133             $instancesql = ' = :instanceid';
1134             $instanceparams = array('instanceid' => $this->instancefilter);
1135         } else {
1136             list($instancesql, $instanceparams) = $DB->get_in_or_equal(array_keys($instances), SQL_PARAMS_NAMED, 'instanceid0000');
1137         }
1138
1139         $userfields = user_picture::fields('u');
1140         list($idsql, $idparams) = $DB->get_in_or_equal($userids, SQL_PARAMS_NAMED, 'userid0000');
1141
1142         list($sort, $sortparams) = users_order_by_sql('u');
1143
1144         $sql = "SELECT ue.id AS ueid, ue.status, ue.enrolid, ue.userid, ue.timestart, ue.timeend, ue.modifierid, ue.timecreated, ue.timemodified, $userfields
1145                   FROM {user_enrolments} ue
1146              LEFT JOIN {user} u ON u.id = ue.userid
1147                  WHERE ue.enrolid $instancesql AND
1148                        u.id $idsql
1149               ORDER BY $sort";
1150
1151         $rs = $DB->get_recordset_sql($sql, $idparams + $instanceparams + $sortparams);
1152         $users = array();
1153         foreach ($rs as $ue) {
1154             $user = user_picture::unalias($ue);
1155             $ue->id = $ue->ueid;
1156             unset($ue->ueid);
1157             if (!array_key_exists($user->id, $users)) {
1158                 $user->enrolments = array();
1159                 $users[$user->id] = $user;
1160             }
1161             $ue->enrolmentinstance = $instances[$ue->enrolid];
1162             $ue->enrolmentplugin = $plugins[$ue->enrolmentinstance->enrol];
1163             $users[$user->id]->enrolments[$ue->id] = $ue;
1164         }
1165         $rs->close();
1166         return $users;
1167     }
1168 }
1169
1170 /**
1171  * A button that is used to enrol users in a course
1172  *
1173  * @copyright 2010 Sam Hemelryk
1174  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
1175  */
1176 class enrol_user_button extends single_button {
1177
1178     /**
1179      * An array containing JS YUI modules required by this button
1180      * @var array
1181      */
1182     protected $jsyuimodules = array();
1183
1184     /**
1185      * An array containing JS initialisation calls required by this button
1186      * @var array
1187      */
1188     protected $jsinitcalls = array();
1189
1190     /**
1191      * An array strings required by JS for this button
1192      * @var array
1193      */
1194     protected $jsstrings = array();
1195
1196     /**
1197      * Initialises the new enrol_user_button
1198      *
1199      * @staticvar int $count The number of enrol user buttons already created
1200      * @param moodle_url $url
1201      * @param string $label The text to display in the button
1202      * @param string $method Either post or get
1203      */
1204     public function __construct(moodle_url $url, $label, $method = 'post') {
1205         static $count = 0;
1206         $count ++;
1207         parent::__construct($url, $label, $method);
1208         $this->class = 'singlebutton enrolusersbutton';
1209         $this->formid = 'enrolusersbutton-'.$count;
1210     }
1211
1212     /**
1213      * Adds a YUI module call that will be added to the page when the button is used.
1214      *
1215      * @param string|array $modules One or more modules to require
1216      * @param string $function The JS function to call
1217      * @param array $arguments An array of arguments to pass to the function
1218      * @param string $galleryversion The YUI gallery version of any modules required
1219      * @param bool $ondomready If true the call is postponed until the DOM is finished loading
1220      */
1221     public function require_yui_module($modules, $function, array $arguments = null, $galleryversion = '2010.04.08-12-35', $ondomready = false) {
1222         $js = new stdClass;
1223         $js->modules = (array)$modules;
1224         $js->function = $function;
1225         $js->arguments = $arguments;
1226         $js->galleryversion = $galleryversion;
1227         $js->ondomready = $ondomready;
1228         $this->jsyuimodules[] = $js;
1229     }
1230
1231     /**
1232      * Adds a JS initialisation call to the page when the button is used.
1233      *
1234      * @param string $function The function to call
1235      * @param array $extraarguments An array of arguments to pass to the function
1236      * @param bool $ondomready If true the call is postponed until the DOM is finished loading
1237      * @param array $module A module definition
1238      */
1239     public function require_js_init_call($function, array $extraarguments = null, $ondomready = false, array $module = null) {
1240         $js = new stdClass;
1241         $js->function = $function;
1242         $js->extraarguments = $extraarguments;
1243         $js->ondomready = $ondomready;
1244         $js->module = $module;
1245         $this->jsinitcalls[] = $js;
1246     }
1247
1248     /**
1249      * Requires strings for JS that will be loaded when the button is used.
1250      *
1251      * @param type $identifiers
1252      * @param string $component
1253      * @param mixed $a
1254      */
1255     public function strings_for_js($identifiers, $component = 'moodle', $a = null) {
1256         $string = new stdClass;
1257         $string->identifiers = (array)$identifiers;
1258         $string->component = $component;
1259         $string->a = $a;
1260         $this->jsstrings[] = $string;
1261     }
1262
1263     /**
1264      * Initialises the JS that is required by this button
1265      *
1266      * @param moodle_page $page
1267      */
1268     public function initialise_js(moodle_page $page) {
1269         foreach ($this->jsyuimodules as $js) {
1270             $page->requires->yui_module($js->modules, $js->function, $js->arguments, $js->galleryversion, $js->ondomready);
1271         }
1272         foreach ($this->jsinitcalls as $js) {
1273             $page->requires->js_init_call($js->function, $js->extraarguments, $js->ondomready, $js->module);
1274         }
1275         foreach ($this->jsstrings as $string) {
1276             $page->requires->strings_for_js($string->identifiers, $string->component, $string->a);
1277         }
1278     }
1279 }
1280
1281 /**
1282  * User enrolment action
1283  *
1284  * This class is used to manage a renderable ue action such as editing an user enrolment or deleting
1285  * a user enrolment.
1286  *
1287  * @copyright  2011 Sam Hemelryk
1288  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
1289  */
1290 class user_enrolment_action implements renderable {
1291
1292     /**
1293      * The icon to display for the action
1294      * @var pix_icon
1295      */
1296     protected $icon;
1297
1298     /**
1299      * The title for the action
1300      * @var string
1301      */
1302     protected $title;
1303
1304     /**
1305      * The URL to the action
1306      * @var moodle_url
1307      */
1308     protected $url;
1309
1310     /**
1311      * An array of HTML attributes
1312      * @var array
1313      */
1314     protected $attributes = array();
1315
1316     /**
1317      * Constructor
1318      * @param pix_icon $icon
1319      * @param string $title
1320      * @param moodle_url $url
1321      * @param array $attributes
1322      */
1323     public function __construct(pix_icon $icon, $title, $url, array $attributes = null) {
1324         $this->icon = $icon;
1325         $this->title = $title;
1326         $this->url = new moodle_url($url);
1327         if (!empty($attributes)) {
1328             $this->attributes = $attributes;
1329         }
1330         $this->attributes['title'] = $title;
1331     }
1332
1333     /**
1334      * Returns the icon for this action
1335      * @return pix_icon
1336      */
1337     public function get_icon() {
1338         return $this->icon;
1339     }
1340
1341     /**
1342      * Returns the title for this action
1343      * @return string
1344      */
1345     public function get_title() {
1346         return $this->title;
1347     }
1348
1349     /**
1350      * Returns the URL for this action
1351      * @return moodle_url
1352      */
1353     public function get_url() {
1354         return $this->url;
1355     }
1356
1357     /**
1358      * Returns the attributes to use for this action
1359      * @return array
1360      */
1361     public function get_attributes() {
1362         return $this->attributes;
1363     }
1364 }
1365
1366 class enrol_ajax_exception extends moodle_exception {
1367     /**
1368      * Constructor
1369      * @param string $errorcode The name of the string from error.php to print
1370      * @param string $module name of module
1371      * @param string $link The url where the user will be prompted to continue. If no url is provided the user will be directed to the site index page.
1372      * @param object $a Extra words and phrases that might be required in the error string
1373      * @param string $debuginfo optional debugging information
1374      */
1375     public function __construct($errorcode, $link = '', $a = NULL, $debuginfo = null) {
1376         parent::__construct($errorcode, 'enrol', $link, $a, $debuginfo);
1377     }
1378 }
1379
1380 /**
1381  * This class is used to manage a bulk operations for enrolment plugins.
1382  *
1383  * @copyright 2011 Sam Hemelryk
1384  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
1385  */
1386 abstract class enrol_bulk_enrolment_operation {
1387
1388     /**
1389      * The course enrolment manager
1390      * @var course_enrolment_manager
1391      */
1392     protected $manager;
1393
1394     /**
1395      * The enrolment plugin to which this operation belongs
1396      * @var enrol_plugin
1397      */
1398     protected $plugin;
1399
1400     /**
1401      * Contructor
1402      * @param course_enrolment_manager $manager
1403      * @param stdClass $plugin
1404      */
1405     public function __construct(course_enrolment_manager $manager, enrol_plugin $plugin = null) {
1406         $this->manager = $manager;
1407         $this->plugin = $plugin;
1408     }
1409
1410     /**
1411      * Returns a moodleform used for this operation, or false if no form is required and the action
1412      * should be immediatly processed.
1413      *
1414      * @param moodle_url|string $defaultaction
1415      * @param mixed $defaultcustomdata
1416      * @return enrol_bulk_enrolment_change_form|moodleform|false
1417      */
1418     public function get_form($defaultaction = null, $defaultcustomdata = null) {
1419         return false;
1420     }
1421
1422     /**
1423      * Returns the title to use for this bulk operation
1424      *
1425      * @return string
1426      */
1427     abstract public function get_title();
1428
1429     /**
1430      * Returns the identifier for this bulk operation.
1431      * This should be the same identifier used by the plugins function when returning
1432      * all of its bulk operations.
1433      *
1434      * @return string
1435      */
1436     abstract public function get_identifier();
1437
1438     /**
1439      * Processes the bulk operation on the given users
1440      *
1441      * @param course_enrolment_manager $manager
1442      * @param array $users
1443      * @param stdClass $properties
1444      */
1445     abstract public function process(course_enrolment_manager $manager, array $users, stdClass $properties);
1446 }