moodle/enrol/self/lib.php

<?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/>.

/**
 * Self enrolment plugin.
 *
 * @package    enrol
 * @subpackage self
 * @copyright  2010 Petr Skoda  {@link http://skodak.org}
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

/**
 * Self enrolment plugin implementation.
 * @author Petr Skoda
 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
class enrol_self_plugin extends enrol_plugin {

    /**
     * Returns localised name of enrol instance
     *
     * @param object $instance (null is accepted too)
     * @return string
     */
    public function get_instance_name($instance) {
        global $DB;

        if (empty($instance->name)) {
            if (!empty($instance->roleid) and $role = $DB->get_record('role', array('id'=>$instance->roleid))) {
                $role = ' (' . role_get_name($role, get_context_instance(CONTEXT_COURSE, $instance->courseid)) . ')';
            } else {
                $role = '';
            }
            $enrol = $this->get_name();
            return get_string('pluginname', 'enrol_'.$enrol) . $role;
        } else {
            return format_string($instance->name);
        }
    }

    public function roles_protected() {
        // users may tweak the roles later
        return false;
    }

    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;
    }

    public function show_enrolme_link(stdClass $instance) {
        return ($instance->status == ENROL_INSTANCE_ENABLED);
    }

    /**
     * Sets up navigation entries.
     *
     * @param object $instance
     * @return void
     */
    public function add_course_navigation($instancesnode, stdClass $instance) {
        if ($instance->enrol !== 'self') {
             throw new coding_exception('Invalid enrol instance type!');
        }

        $context = get_context_instance(CONTEXT_COURSE, $instance->courseid);
        if (has_capability('enrol/self:config', $context)) {
            $managelink = new moodle_url('/enrol/self/edit.php', array('courseid'=>$instance->courseid, 'id'=>$instance->id));
            $instancesnode->add($this->get_instance_name($instance), $managelink, navigation_node::TYPE_SETTING);
        }
    }

    /**
     * Returns edit icons for the page with list of instances
     * @param stdClass $instance
     * @return array
     */
    public function get_action_icons(stdClass $instance) {
        global $OUTPUT;

        if ($instance->enrol !== 'self') {
            throw new coding_exception('invalid enrol instance!');
        }
        $context = get_context_instance(CONTEXT_COURSE, $instance->courseid);

        $icons = array();

        if (has_capability('enrol/self:config', $context)) {
            $editlink = new moodle_url("/enrol/self/edit.php", array('courseid'=>$instance->courseid, 'id'=>$instance->id));
            $icons[] = $OUTPUT->action_icon($editlink, new pix_icon('i/edit', get_string('edit'), 'core', array('class'=>'icon')));
        }

        return $icons;
    }

    /**
     * Returns link to page which may be used to add new instance of enrolment plugin in course.
     * @param int $courseid
     * @return moodle_url page url
     */
    public function get_candidate_link($courseid) {
        $context = get_context_instance(CONTEXT_COURSE, $courseid, MUST_EXIST);

        if (!has_capability('moodle/course:enrolconfig', $context) or !has_capability('enrol/manual:config', $context)) {
            return NULL;
        }
        // multiple instances supported - different roles with different password
        return new moodle_url('/enrol/self/edit.php', array('courseid'=>$courseid));
    }

    /**
     * Creates course enrol form, checks if form submitted
     * and enrols user if necessary. It can also redirect.
     *
     * @param stdClass $instance
     * @return string html text, usually a form in a text box
     */
    public function enrol_page_hook(stdClass $instance) {
        global $CFG, $OUTPUT, $SESSION, $USER, $DB;

        if (isguestuser()) {
            // can not enrol guest!!
            return null;
        }
        if ($DB->record_exists('user_enrolments', array('userid'=>$USER->id, 'enrolid'=>$instance->id))) {
            //TODO: maybe we should tell them they are already enrolled, but can not access the course
            return null;
        }

        if ($instance->enrolstartdate != 0 and $instance->enrolstartdate < time) {
            //TODO: inform that we can not enrol yet
            return null;
        }

        if ($instance->enrolenddate != 0 and $instance->enrolenddate > time) {
            //TODO: inform that enrolment is not possible any more
            return null;
        }

        require_once("$CFG->dirroot/enrol/self/locallib.php");
        $form = new enrol_self_enrol_form(NULL, $instance);
        $instanceid = optional_param('instance', 0, PARAM_INT);

        if ($instance->id == $instanceid) {
            if ($data = $form->get_data()) {
                $enrol = enrol_get_plugin('self');
                $timestart = time();
                if ($instance->enrolperiod) {
                    $tineend = $timestart + $instance->enrolperiod;
                } else {
                    $tineend = 0;
                }

                $this->enrol_user($instance, $USER->id, $instance->roleid, $timestart, $tineend);
                add_to_log($instance->courseid, 'course', 'enrol', '../enrol/users.php?id='.$instance->courseid, $instance->courseid); //there should be userid somewhere!
                // send welcome
                if ($this->get_config('sendcoursewelcomemessage')) {
                    $this->email_welcome_message($instance, $USER);
                }
            }
        }

        ob_start();
        $form->display();
        $output = ob_get_clean();

        return $OUTPUT->box($output);
    }

    /**
     * Add new instance of enrol plugin with default settings.
     * @param object $course
     * @return int id of new instance
     */
    public function add_default_instance($course) {
        global $DB;

        $fields = array('customint1'=>$this->get_config('groupkey'), 'enrolperiod'=>$this->get_config('enrolperiod', 0), 'roleid'=>$this->get_config('roleid', 0));

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

        if ($this->get_config('requirepassword')) {
            $fields['password'] = generate_password(20);
        }

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

    /**
     * Send welcome email to specified user
     *
     * @param object $instance
     * @param object $user user record
     * @return void
     */
    protected function email_welcome_message($instance, $user) {
        global $CFG, $DB;

        $course = $DB->get_record('course', array('id'=>$instance->courseid), '*', MUST_EXIST);

        if (!empty($instance->customtext1)) {
            //note: there is no gui for this yet, do we really need it?
            $message = formaat_string($instance->customtext1);
        } else {
            $a = new object();
            $a->coursename = format_string($course->fullname);
            $a->profileurl = "$CFG->wwwroot/user/view.php?id=$user->id&course=$course->id";
            $message = get_string("welcometocoursetext", 'enrol_self', $a);
        }

        $subject = get_string('welcometocourse', 'enrol_self', format_string($course->fullname));

        $context = get_context_instance(CONTEXT_COURSE, $course->id);
        $rusers = null;
        if (!empty($CFG->coursecontact)) {
            $croles = explode(',', $CFG->coursecontact);
            $rusers = get_role_users($croles, $context, true, '', 'r.sortorder ASC, u.lastname ASC');
        }
        if ($rusers) {
            $contact = reset($rusers);
        } else {
            $contact = get_admin();
        }

        email_to_user($user, $contact, $subject, $message);
    }
}