Proyectos de Subversion Moodle

<?php

// This file is part of Moodle - http://moodle.org/

//

// Moodle is free software: you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

//

// Moodle is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU General Public License for more details.

//

// You should have received a copy of the GNU General Public License

// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**

 * Manual enrolment plugin main library file.

 *

 * @package    enrol_manual

 * @copyright  2010 Petr Skoda {@link http://skodak.org}

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

defined('MOODLE_INTERNAL') || die();

class enrol_manual_plugin extends enrol_plugin {

    protected $lasternoller = null;

    protected $lasternollerinstanceid = 0;

    public function roles_protected() {

        // Users may tweak the roles later.

        return false;

    }

    public function allow_enrol(stdClass $instance) {

        // Users with enrol cap may unenrol other users manually manually.

        return true;

    }

    public function allow_unenrol(stdClass $instance) {

        // Users with unenrol cap may unenrol other users manually manually.

        return true;

    }

    public function allow_manage(stdClass $instance) {

        // Users with manage cap may tweak period and status.

        return true;

    }

    /**

     * Returns link to manual enrol UI if exists.

     * Does the access control tests automatically.

     *

     * @param stdClass $instance

     * @return moodle_url

     */

    public function get_manual_enrol_link($instance) {

        $name = $this->get_name();

        if ($instance->enrol !== $name) {

            throw new coding_exception('invalid enrol instance!');

        }

        if (!enrol_is_enabled($name)) {

            return NULL;

        }

        $context = context_course::instance($instance->courseid, MUST_EXIST);

        if (!has_capability('enrol/manual:enrol', $context)) {

            // Note: manage capability not used here because it is used for editing

            // of existing enrolments which is not possible here.

            return NULL;

        }

        return new moodle_url('/enrol/manual/manage.php', array('enrolid'=>$instance->id, 'id'=>$instance->courseid));

    }

    /**

     * Return true if we can add a new instance to this course.

     *

     * @param int $courseid

     * @return boolean

     */

    public function can_add_instance($courseid) {

        global $DB;

        $context = context_course::instance($courseid, MUST_EXIST);

        if (!has_capability('moodle/course:enrolconfig', $context) or !has_capability('enrol/manual:config', $context)) {

            return false;

        }

        if ($DB->record_exists('enrol', array('courseid'=>$courseid, 'enrol'=>'manual'))) {

            // Multiple instances not supported.

            return false;

        }

        return true;

    }

    /**

     * Returns edit icons for the page with list of instances.

     * @param stdClass $instance

     * @return array

     */

    public function get_action_icons(stdClass $instance) {

        global $OUTPUT;

        $context = context_course::instance($instance->courseid);

        $icons = array();

        if (has_capability('enrol/manual:enrol', $context) or has_capability('enrol/manual:unenrol', $context)) {

            $managelink = new moodle_url("/enrol/manual/manage.php", array('enrolid'=>$instance->id));

            $icons[] = $OUTPUT->action_icon($managelink, new pix_icon('t/enrolusers', get_string('enrolusers', 'enrol_manual'), 'core', array('class'=>'iconsmall')));

        }

        if (has_any_capability(['enrol/manual:config', 'moodle/course:editcoursewelcomemessage'], $context)) {

            $linkparams = [

                'courseid' => $instance->courseid,

                'id' => $instance->id,

                'type' => $instance->enrol,

            ];

            $editlink = new moodle_url('/enrol/editinstance.php', $linkparams);

            $icon = new pix_icon('t/edit', get_string('edit'), 'core', ['class' => 'iconsmall']);

            $icons[] = $OUTPUT->action_icon($editlink, $icon);

        }

        return $icons;

    }

    /**

     * Add new instance of enrol plugin with default settings.

     * @param stdClass $course

     * @return int id of new instance, null if can not be created

     */

    public function add_default_instance($course) {

        $expirynotify = $this->get_config('expirynotify', 0);

        $fields = array(

            'status'          => $this->get_config('status'),

            'roleid'          => $this->get_config('roleid', 0),

            'enrolperiod'     => $this->get_config('enrolperiod', 0),

            'expirynotify'    => $expirynotify,

            'notifyall'       => $expirynotify == 2 ? 1 : 0,

            'expirythreshold' => $this->get_config('expirythreshold', 86400),

            'customint1' => $this->get_config('sendcoursewelcomemessage'),

        );

        return $this->add_instance($course, $fields);

    }

    /**

     * Add new instance of enrol plugin.

     * @param stdClass $course

     * @param array instance fields

     * @return int id of new instance, null if can not be created

     */

    public function add_instance($course, ?array $fields = NULL) {

        global $DB;

        if ($DB->record_exists('enrol', array('courseid'=>$course->id, 'enrol'=>'manual'))) {

            // only one instance allowed, sorry

            return NULL;

        }

        return parent::add_instance($course, $fields);

    }

    /**

     * Update instance of enrol plugin.

     * @param stdClass $instance

     * @param stdClass $data modified instance fields

     * @return boolean

     */

    public function update_instance($instance, $data) {

        global $DB;

        // Delete all other instances, leaving only one.

        if ($instances = $DB->get_records('enrol', array('courseid' => $instance->courseid, 'enrol' => 'manual'), 'id ASC')) {

            foreach ($instances as $anotherinstance) {

                if ($anotherinstance->id != $instance->id) {

                    $this->delete_instance($anotherinstance);

                }

            }

        }

        // This method is used when configuring the enrolment method, and when only updating the welcome message.

        // The 'expirynotify' property won't be set when updating the welcome message.

        if (isset($data->expirynotify)) {

            $data->notifyall = $data->expirynotify == 2 ? 1 : 0;

        }

        return parent::update_instance($instance, $data);

    }

    /**

     * Returns a button to manually enrol users through the manual enrolment plugin.

     *

     * By default the first manual enrolment plugin instance available in the course is used.

     * If no manual enrolment instances exist within the course then false is returned.

     *

     * This function also adds a quickenrolment JS ui to the page so that users can be enrolled

     * via AJAX.

     *

     * @param course_enrolment_manager $manager

     * @return enrol_user_button

     */

    public function get_manual_enrol_button(course_enrolment_manager $manager) {

        global $CFG, $PAGE;

        require_once($CFG->dirroot.'/cohort/lib.php');

        static $called = false;

        $instance = null;

        foreach ($manager->get_enrolment_instances() as $tempinstance) {

            if ($tempinstance->enrol == 'manual') {

                if ($instance === null) {

                    $instance = $tempinstance;

                }

            }

        }

        if (empty($instance)) {

            return false;

        }

        $link = $this->get_manual_enrol_link($instance);

        if (!$link) {

            return false;

        }

        $button = new enrol_user_button($link, get_string('enrolusers', 'enrol_manual'), 'get');

        $button->class .= ' enrol_manual_plugin';

        $button->type = single_button::BUTTON_PRIMARY;

        $context = context_course::instance($instance->courseid);

        $arguments = array('contextid' => $context->id);

        if (!$called) {

            $called = true;

            // Calling the following more than once will cause unexpected results.

            $PAGE->requires->js_call_amd('enrol_manual/quickenrolment', 'init', array($arguments));

        }

        return $button;

    }

    /**

     * Sync all meta course links.

     *

     * @param progress_trace $trace

     * @param int $courseid one course, empty mean all

     * @return int 0 means ok, 1 means error, 2 means plugin disabled

     */

    public function sync(progress_trace $trace, $courseid = null) {

        global $DB;

        if (!enrol_is_enabled('manual')) {

            $trace->finished();

            return 2;

        }

        // Unfortunately this may take a long time, execution can be interrupted safely here.

        core_php_time_limit::raise();

        raise_memory_limit(MEMORY_HUGE);

        $trace->output('Verifying manual enrolment expiration...');

        $params = array('now'=>time(), 'useractive'=>ENROL_USER_ACTIVE, 'courselevel'=>CONTEXT_COURSE);

        $coursesql = "";

        if ($courseid) {

            $coursesql = "AND e.courseid = :courseid";

            $params['courseid'] = $courseid;

        }

        // Deal with expired accounts.

        $action = $this->get_config('expiredaction', ENROL_EXT_REMOVED_KEEP);

        if ($action == ENROL_EXT_REMOVED_UNENROL) {

            $instances = array();

            $sql = "SELECT ue.*, e.courseid, c.id AS contextid

                      FROM {user_enrolments} ue

                      JOIN {enrol} e ON (e.id = ue.enrolid AND e.enrol = 'manual')

                      JOIN {context} c ON (c.instanceid = e.courseid AND c.contextlevel = :courselevel)

                     WHERE ue.timeend > 0 AND ue.timeend < :now

                           $coursesql";

            $rs = $DB->get_recordset_sql($sql, $params);

            foreach ($rs as $ue) {

                if (empty($instances[$ue->enrolid])) {

                    $instances[$ue->enrolid] = $DB->get_record('enrol', array('id'=>$ue->enrolid));

                }

                $instance = $instances[$ue->enrolid];

                // Always remove all manually assigned roles here, this may break enrol_self roles but we do not want hardcoded hacks here.

                role_unassign_all(array('userid'=>$ue->userid, 'contextid'=>$ue->contextid, 'component'=>'', 'itemid'=>0), true);

                $this->unenrol_user($instance, $ue->userid);

                $trace->output("unenrolling expired user $ue->userid from course $instance->courseid", 1);

            }

            $rs->close();

            unset($instances);

        } else if ($action == ENROL_EXT_REMOVED_SUSPENDNOROLES or $action == ENROL_EXT_REMOVED_SUSPEND) {

            $instances = array();

            $sql = "SELECT ue.*, e.courseid, c.id AS contextid

                      FROM {user_enrolments} ue

                      JOIN {enrol} e ON (e.id = ue.enrolid AND e.enrol = 'manual')

                      JOIN {context} c ON (c.instanceid = e.courseid AND c.contextlevel = :courselevel)

                     WHERE ue.timeend > 0 AND ue.timeend < :now

                           AND ue.status = :useractive

                           $coursesql";

            $rs = $DB->get_recordset_sql($sql, $params);

            foreach ($rs as $ue) {

                if (empty($instances[$ue->enrolid])) {

                    $instances[$ue->enrolid] = $DB->get_record('enrol', array('id'=>$ue->enrolid));

                }

                $instance = $instances[$ue->enrolid];

                if ($action == ENROL_EXT_REMOVED_SUSPENDNOROLES) {

                    // Remove all manually assigned roles here, this may break enrol_self roles but we do not want hardcoded hacks here.

                    role_unassign_all(array('userid'=>$ue->userid, 'contextid'=>$ue->contextid, 'component'=>'', 'itemid'=>0), true);

                    $this->update_user_enrol($instance, $ue->userid, ENROL_USER_SUSPENDED);

                    $trace->output("suspending expired user $ue->userid in course $instance->courseid, roles unassigned", 1);

                } else {

                    $this->update_user_enrol($instance, $ue->userid, ENROL_USER_SUSPENDED);

                    $trace->output("suspending expired user $ue->userid in course $instance->courseid, roles kept", 1);

                }

            }

            $rs->close();

            unset($instances);

        } else {

            // ENROL_EXT_REMOVED_KEEP means no changes.

        }

        $trace->output('...manual enrolment updates finished.');

        $trace->finished();

        return 0;

    }

    /**

     * Returns the user who is responsible for manual enrolments in given instance.

     *

     * Usually it is the first editing teacher - the person with "highest authority"

     * as defined by sort_by_roleassignment_authority() having 'enrol/manual:manage'

     * capability.

     *

     * @param int $instanceid enrolment instance id

     * @return stdClass user record

     */

    protected function get_enroller($instanceid) {

        global $DB;

        if ($this->lasternollerinstanceid == $instanceid and $this->lasternoller) {

            return $this->lasternoller;

        }

        $instance = $DB->get_record('enrol', array('id'=>$instanceid, 'enrol'=>$this->get_name()), '*', MUST_EXIST);

        $context = context_course::instance($instance->courseid);

        if ($users = get_enrolled_users($context, 'enrol/manual:manage')) {

            $users = sort_by_roleassignment_authority($users, $context);

            $this->lasternoller = reset($users);

            unset($users);

        } else {

            $this->lasternoller = parent::get_enroller($instanceid);

        }

        $this->lasternollerinstanceid = $instanceid;

        return $this->lasternoller;

    }

    /**

     * The manual plugin has several bulk operations that can be performed.

     * @param course_enrolment_manager $manager

     * @return array

     */

    public function get_bulk_operations(course_enrolment_manager $manager) {

        global $CFG;

        require_once($CFG->dirroot.'/enrol/manual/locallib.php');

        $context = $manager->get_context();

        $bulkoperations = array();

        if (has_capability("enrol/manual:manage", $context)) {

            $bulkoperations['editselectedusers'] = new enrol_manual_editselectedusers_operation($manager, $this);

        }

        if (has_capability("enrol/manual:unenrol", $context)) {

            $bulkoperations['deleteselectedusers'] = new enrol_manual_deleteselectedusers_operation($manager, $this);

        }

        return $bulkoperations;

    }

    /**

     * Restore instance and map settings.

     *

     * @param restore_enrolments_structure_step $step

     * @param stdClass $data

     * @param stdClass $course

     * @param int $oldid

     */

    public function restore_instance(restore_enrolments_structure_step $step, stdClass $data, $course, $oldid) {

        global $DB;

        // There is only I manual enrol instance allowed per course.

        if ($instances = $DB->get_records('enrol', array('courseid'=>$data->courseid, 'enrol'=>'manual'), 'id')) {

            $instance = reset($instances);

            $instanceid = $instance->id;

        } else {

            $instanceid = $this->add_instance($course, (array)$data);

        }

        $step->set_mapping('enrol', $oldid, $instanceid);

    }

    /**

     * Restore user enrolment.

     *

     * @param restore_enrolments_structure_step $step

     * @param stdClass $data

     * @param stdClass $instance

     * @param int $oldinstancestatus

     * @param int $userid

     */

    public function restore_user_enrolment(restore_enrolments_structure_step $step, $data, $instance, $userid, $oldinstancestatus) {

        global $DB;

        // Note: this is a bit tricky because other types may be converted to manual enrolments,

        //       and manual is restricted to one enrolment per user.

        $ue = $DB->get_record('user_enrolments', array('enrolid'=>$instance->id, 'userid'=>$userid));

        $enrol = false;

        if ($ue and $ue->status == ENROL_USER_ACTIVE) {

            // We do not want to restrict current active enrolments, let's kind of merge the times only.

            // This prevents some teacher lockouts too.

            if ($data->status == ENROL_USER_ACTIVE) {

                if ($data->timestart > $ue->timestart) {

                    $data->timestart = $ue->timestart;

                    $enrol = true;

                }

                if ($data->timeend == 0) {

                    if ($ue->timeend != 0) {

                        $enrol = true;

                    }

                } else if ($ue->timeend == 0) {

                    $data->timeend = 0;

                } else if ($data->timeend < $ue->timeend) {

                    $data->timeend = $ue->timeend;

                    $enrol = true;

                }

            }

        } else {

            if ($instance->status == ENROL_INSTANCE_ENABLED and $oldinstancestatus != ENROL_INSTANCE_ENABLED) {

                // Make sure that user enrolments are not activated accidentally,

                // we do it only here because it is not expected that enrolments are migrated to other plugins.

                $data->status = ENROL_USER_SUSPENDED;

            }

            $enrol = true;

        }

        if ($enrol) {

            $this->enrol_user($instance, $userid, null, $data->timestart, $data->timeend, $data->status);

        }

    }

    /**

     * Restore role assignment.

     *

     * @param stdClass $instance

     * @param int $roleid

     * @param int $userid

     * @param int $contextid

     */

    public function restore_role_assignment($instance, $roleid, $userid, $contextid) {

        // This is necessary only because we may migrate other types to this instance,

        // we do not use component in manual or self enrol.

        role_assign($roleid, $userid, $contextid, '', 0);

    }

    /**

     * Restore user group membership.

     * @param stdClass $instance

     * @param int $groupid

     * @param int $userid

     */

    public function restore_group_member($instance, $groupid, $userid) {

        global $CFG;

        require_once("$CFG->dirroot/group/lib.php");

        // This might be called when forcing restore as manual enrolments.

        groups_add_member($groupid, $userid);

    }

    /**

     * Is it possible to delete enrol instance via standard UI?

     *

     * @param object $instance

     * @return bool

     */

    public function can_delete_instance($instance) {

        $context = context_course::instance($instance->courseid);

        return has_capability('enrol/manual:config', $context);

    }

    /**

     * Is it possible to hide/show enrol instance via standard UI?

     *

     * @param stdClass $instance

     * @return bool

     */

    public function can_hide_show_instance($instance) {

        $context = context_course::instance($instance->courseid);

        return has_capability('enrol/manual:config', $context);

    }

    /**

     * Enrol all not enrolled cohort members into course via enrol instance.

     *

     * @param stdClass $instance

     * @param int $cohortid

     * @param int $roleid optional role id

     * @param int $timestart 0 means unknown

     * @param int $timeend 0 means forever

     * @param int $status default to ENROL_USER_ACTIVE for new enrolments, no change by default in updates

     * @param bool $recovergrades restore grade history

     * @return int The number of enrolled cohort users

     */

    public function enrol_cohort(stdClass $instance, $cohortid, $roleid = null, $timestart = 0, $timeend = 0, $status = null, $recovergrades = null) {

        global $DB;

        $context = context_course::instance($instance->courseid);

        list($esql, $params) = get_enrolled_sql($context);

        $sql = "SELECT cm.userid FROM {cohort_members} cm LEFT JOIN ($esql) u ON u.id = cm.userid ".

            "WHERE cm.cohortid = :cohortid AND u.id IS NULL";

        $params['cohortid'] = $cohortid;

        $members = $DB->get_fieldset_sql($sql, $params);

        foreach ($members as $userid) {

            $this->enrol_user($instance, $userid, $roleid, $timestart, $timeend, $status, $recovergrades);

        }

        return count($members);

    }

    /**

     * We are a good plugin and don't invent our own UI/validation code path.

     *

     * @return boolean

     */

    public function use_standard_editing_ui() {

        return true;

    }

    /**

     * Return an array of valid options for the status.

     *

     * @return array

     */

    protected function get_status_options() {

        $options = array(ENROL_INSTANCE_ENABLED  => get_string('yes'),

                         ENROL_INSTANCE_DISABLED => get_string('no'));

        return $options;

    }

    /**

     * Return an array of valid options for the roleid.

     *

     * @param stdClass $instance

     * @param context $context

     * @return array

     */

    protected function get_roleid_options($instance, $context) {

        if ($instance->id) {

            $roles = get_default_enrol_roles($context, $instance->roleid);

        } else {

            $roles = get_default_enrol_roles($context, $this->get_config('roleid'));

        }

        return $roles;

    }

    /**

     * Return an array of valid options for the expirynotify.

     *

     * @return array

     */

    protected function get_expirynotify_options() {

        $options = array(

            1 => get_string('expirynotifyenroller', 'core_enrol'),

            2 => get_string('expirynotifyall', 'core_enrol')

        );

        return $options;

    }

    /**

     * Add elements to the edit instance form.

     *

     * @param stdClass $instance

     * @param MoodleQuickForm $mform

     * @param context $context

     * @return bool

     */

    public function edit_instance_form($instance, MoodleQuickForm $mform, $context) {

        // Main fields.

        if (has_capability('enrol/manual:config', $context)) {

            $options = $this->get_status_options();

            $mform->addElement('select', 'status', get_string('status', 'enrol_manual'), $options);

            $mform->addHelpButton('status', 'status', 'enrol_manual');

            $mform->setDefault('status', $this->get_config('status'));

            $roles = $this->get_roleid_options($instance, $context);

            $mform->addElement('select', 'roleid', get_string('defaultrole', 'role'), $roles);

            $mform->setDefault('roleid', $this->get_config('roleid'));

            $options = ['optional' => true, 'defaultunit' => 86400];

            $mform->addElement('duration', 'enrolperiod', get_string('defaultperiod', 'enrol_manual'), $options);

            $mform->setDefault('enrolperiod', $this->get_config('enrolperiod'));

            $mform->addHelpButton('enrolperiod', 'defaultperiod', 'enrol_manual');

            $options = $this->get_expirynotify_options();

            $mform->addElement('select', 'expirynotify', get_string('expirynotify', 'core_enrol'), $options);

            $mform->addHelpButton('expirynotify', 'expirynotify', 'core_enrol');

            $options = ['optional' => false, 'defaultunit' => 86400];

            $mform->addElement('duration', 'expirythreshold', get_string('expirythreshold', 'core_enrol'), $options);

            $mform->addHelpButton('expirythreshold', 'expirythreshold', 'core_enrol');

            $mform->disabledIf('expirythreshold', 'expirynotify', 'eq', 0);

        }

        // Course welcome message.

        if (has_any_capability(['enrol/manual:config', 'moodle/course:editcoursewelcomemessage'], $context)) {

            $mform->addElement(

                'select',

                'customint1',

                get_string(

                    identifier: 'sendcoursewelcomemessage',

                    component: 'core_enrol',

                ),

                enrol_send_welcome_email_options(),

            );

            $mform->addHelpButton(

                elementname: 'customint1',

                identifier: 'sendcoursewelcomemessage',

                component: 'core_enrol',

            );

            $options = [

                'cols' => '60',

                'rows' => '8',

            ];

            $mform->addElement(

                'textarea',

                'customtext1',

                get_string(

                    identifier: 'customwelcomemessage',

                    component: 'core_enrol',

                ),

                $options,

            );

            $mform->setDefault('customtext1', get_string('customwelcomemessageplaceholder', 'core_enrol'));

            $mform->hideIf(

                elementname: 'customtext1',

                dependenton: 'customint1',

                condition: 'eq',

                value: ENROL_DO_NOT_SEND_EMAIL,

            );

            // Static form elements cannot be hidden by hideIf() so we need to add a dummy group.

            // See: https://tracker.moodle.org/browse/MDL-66251.

            $group[] = $mform->createElement(

                'static',

                'customwelcomemessage_extra_help',

                null,

                get_string(

                    identifier: 'customwelcomemessage_help',

                    component: 'core_enrol',

                ),

            );

            $mform->addGroup($group, 'group_customwelcomemessage_extra_help', '', ' ', false);

            $mform->hideIf(

                elementname: 'group_customwelcomemessage_extra_help',

                dependenton: 'customint1',

                condition: 'eq',

                value: ENROL_DO_NOT_SEND_EMAIL,

            );

        }

        // Enrolment changes warning.

        if (has_capability('enrol/manual:config', $context) && enrol_accessing_via_instance($instance)) {

            $warntext = get_string('instanceeditselfwarningtext', 'core_enrol');

            $mform->addElement('static', 'selfwarn', get_string('instanceeditselfwarning', 'core_enrol'), $warntext);

        }

    }

    /**

     * Perform custom validation of the data used to edit the instance.

     *

     * @param array $data array of ("fieldname"=>value) of submitted data

     * @param array $files array of uploaded files "element_name"=>tmp_file_path

     * @param object $instance The instance loaded from the DB

     * @param context $context The context of the instance we are editing

     * @return array of "element_name"=>"error_description" if there are errors,

     *         or an empty array if everything is OK.

     * @return void

     */

    public function edit_instance_validation($data, $files, $instance, $context) {

        $errors = array();

        // This method is used when configuring the enrolment method, and when only updating the welcome message.

        // The 'expirynotify' key won't be set when updating the welcome message.

        if (isset($data['expirynotify']) && $data['expirynotify'] > 0 && $data['expirythreshold'] < DAYSECS) {

            $errors['expirythreshold'] = get_string('errorthresholdlow', 'core_enrol');

        }

        $validstatus = array_keys($this->get_status_options());

        $validroles = array_keys($this->get_roleid_options($instance, $context));

        $validexpirynotify = array_keys($this->get_expirynotify_options());

        $tovalidate = array(

            'status' => $validstatus,

            'roleid' => $validroles,

            'enrolperiod' => PARAM_INT,

            'expirynotify' => $validexpirynotify,

            'expirythreshold' => PARAM_INT

        );

        $typeerrors = $this->validate_param_types($data, $tovalidate);

        $errors = array_merge($errors, $typeerrors);

        return $errors;

    }

    /**

     * Check if enrolment plugin is supported in csv course upload.

     *

     * @return bool

     */

    public function is_csv_upload_supported(): bool {

        return true;

    }

    /**

     * Finds matching instances for a given course.

     *

     * @param array $enrolmentdata enrolment data.

     * @param int $courseid Course ID.

     * @return stdClass|null Matching instance

     */

    public function find_instance(array $enrolmentdata, int $courseid): ?stdClass {

        $instances = enrol_get_instances($courseid, false);

        $instance = null;

        foreach ($instances as $i) {

            if ($i->enrol == 'manual') {

                // There can be only one manual enrol instance so find first available.

                $instance = $i;

                break;

            }

        }

        return $instance;

    }

    /**

     * Fill custom fields data for a given enrolment plugin.

     *

     * @param array $enrolmentdata enrolment data.

     * @param int $courseid Course ID.

     * @return array Updated enrolment data with custom fields info.

     */

    public function fill_enrol_custom_fields(array $enrolmentdata, int $courseid): array {

        return $enrolmentdata + [

            'expirynotify' => 0,

            'expirythreshold' => 0,

        ];

    }

    /**

     * Returns defaults for new instances.

     *

     * @return array

     */

    public function get_instance_defaults(): array {

        $fields['customint1'] = $this->get_config('sendcoursewelcomemessage');

        return $fields;

    }

}

/**

 * Serve the manual enrol users form as a fragment.

 *

 * @param array $args List of named arguments for the fragment loader.

 * @return string

 */

function enrol_manual_output_fragment_enrol_users_form($args) {

    $args = (object) $args;

    $context = $args->context;

    $o = '';

    require_capability('enrol/manual:enrol', $context);

    $mform = new enrol_manual_enrol_users_form(null, $args);

    ob_start();

    $mform->display();

    $o .= ob_get_contents();

    ob_end_clean();

    return $o;

}