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/>.

/**

 * Guest access plugin.

 *

 * This plugin does not add any entries into the user_enrolments table,

 * the access control is granted on the fly via the tricks in require_login().

 *

 * @package    enrol_guest

 * @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_guest_plugin

 *

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

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

 */

class enrol_guest_plugin extends enrol_plugin {

    /**

     * Returns optional enrolment information icons.

     *

     * This is used in course list for quick overview of enrolment options.

     *

     * We are not using single instance parameter because sometimes

     * we might want to prevent icon repetition when multiple instances

     * of one type exist. One instance may also produce several icons.

     *

     * @param array $instances all enrol instances of this type in one course

     * @return array of pix_icon

     */

    public function get_info_icons(array $instances) {

        foreach ($instances as $instance) {

            if ($instance->password !== '') {

                return array(new pix_icon('withpassword', get_string('guestaccess_withpassword', 'enrol_guest'), 'enrol_guest'));

            } else {

                return array(new pix_icon('withoutpassword', get_string('guestaccess_withoutpassword', 'enrol_guest'), 'enrol_guest'));

            }

        }

    }

    /**

     * Enrol a user using a given enrolment instance.

     *

     * @param stdClass $instance

     * @param int $userid

     * @param null $roleid

     * @param int $timestart

     * @param int $timeend

     * @param null $status

     * @param null $recovergrades

     */

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

        // no real enrolments here!

        return;

    }

    /**

     * Enrol a user from a given enrolment instance.

     *

     * @param stdClass $instance

     * @param int $userid

     */

    public function unenrol_user(stdClass $instance, $userid) {

        // nothing to do, we never enrol here!

        return;

    }

    /**

     * Attempt to automatically gain temporary guest access to course,

     * calling code has to make sure the plugin and instance are active.

     *

     * @param stdClass $instance course enrol instance

     * @return bool|int false means no guest access, integer means end of cached time

     */

    public function try_guestaccess(stdClass $instance) {

        global $USER, $CFG;

        $allow = false;

        if ($instance->password === '') {

            $allow = true;

        } else if (isset($USER->enrol_guest_passwords[$instance->id])) { // this is a hack, ideally we should not add stuff to $USER...

            if ($USER->enrol_guest_passwords[$instance->id] === $instance->password) {

                $allow = true;

            }

        } else if (WS_SERVER) { // Mobile app mostly.

            $storedpass = get_user_preferences('enrol_guest_ws_password_'. $instance->id);

            // We check first if there is a supplied password.

            if (!is_null($storedpass)) {

                $allow = $storedpass === $instance->password;

                if (!$allow) {

                    // Reset, probably the course password was changed.

                    unset_user_preference('enrol_guest_ws_password_' . $instance->id);

                }

            }

        }

        if ($allow) {

            // Temporarily assign them some guest role for this context

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

            load_temp_course_role($context, $CFG->guestroleid);

            return ENROL_MAX_TIMESTAMP;

        }

        return false;

    }

    /**

     * Returns true if the current user can add a new instance of enrolment plugin in 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/guest:config', $context)) {

            return false;

        }

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

            return false;

        }

        return true;

    }

    /**

     * 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;

        if ($instance->password === '') {

            return null;

        }

        if (isset($USER->enrol['tempguest'][$instance->courseid]) and $USER->enrol['tempguest'][$instance->courseid] > time()) {

            // no need to show the guest access when user can already enter course as guest

            return null;

        }

        require_once("$CFG->dirroot/enrol/guest/locallib.php");

        $form = new enrol_guest_enrol_form(NULL, $instance);

        $instanceid = optional_param('instance', 0, PARAM_INT);

        if ($instance->id == $instanceid) {

            if ($data = $form->get_data()) {

                // add guest role

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

                $USER->enrol_guest_passwords[$instance->id] = $data->guestpassword; // this is a hack, ideally we should not add stuff to $USER...

                if (isset($USER->enrol['tempguest'][$instance->courseid])) {

                    remove_temp_course_roles($context);

                }

                load_temp_course_role($context, $CFG->guestroleid);

                $USER->enrol['tempguest'][$instance->courseid] = ENROL_MAX_TIMESTAMP;

                // go to the originally requested page

                if (!empty($SESSION->wantsurl)) {

                    $destination = $SESSION->wantsurl;

                    unset($SESSION->wantsurl);

                } else {

                    $destination = "$CFG->wwwroot/course/view.php?id=$instance->courseid";

                }

                redirect($destination);

            }

        }

        ob_start();

        $form->display();

        $output = ob_get_clean();

        return $OUTPUT->box($output, 'generalbox');

    }

    /**

     * Called after updating/inserting course.

     *

     * @param bool $inserted true if course just inserted

     * @param object $course

     * @param object $data form data

     * @return void

     */

    public function course_updated($inserted, $course, $data) {

        global $DB;

        if ($inserted) {

            if (isset($data->enrol_guest_status_0)) {

                $fields = array('status'=>$data->enrol_guest_status_0);

                if ($fields['status'] == ENROL_INSTANCE_ENABLED) {

                    $fields['password'] = $data->enrol_guest_password_0;

                } else {

                    if ($this->get_config('requirepassword')) {

                        $fields['password'] = generate_password(20);

                    }

                }

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

            } else {

                if ($this->get_config('defaultenrol')) {

                    $this->add_default_instance($course);

                }

            }

        } else {

            $instances = $DB->get_records('enrol', array('courseid'=>$course->id, 'enrol'=>'guest'));

            foreach ($instances as $instance) {

                $i = $instance->id;

                if (isset($data->{'enrol_guest_status_'.$i})) {

                    $reset = ($instance->status != $data->{'enrol_guest_status_'.$i});

                    $instance->status       = $data->{'enrol_guest_status_'.$i};

                    $instance->timemodified = time();

                    if ($instance->status == ENROL_INSTANCE_ENABLED) {

                        if ($instance->password !== $data->{'enrol_guest_password_'.$i}) {

                            $reset = true;

                        }

                        $instance->password = $data->{'enrol_guest_password_'.$i};

                    }

                    $DB->update_record('enrol', $instance);

                    \core\event\enrol_instance_updated::create_from_record($instance)->trigger();

                    if ($reset) {

                        $context = context_course::instance($course->id);

                        $context->mark_dirty();

                    }

                }

            }

        }

    }

    /**

     * Add new instance of enrol plugin.

     * @param object $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) {

        $fields = (array)$fields;

        if (!isset($fields['password'])) {

            $fields['password'] = '';

        }

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

    }

    /**

     * Add new instance of enrol plugin with default settings.

     * @param object $course

     * @return int id of new instance

     */

    public function add_default_instance($course) {

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

        if ($this->get_config('requirepassword')) {

            $fields['password'] = generate_password(20);

        }

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

    }

    /**

     * 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;

        if (!$DB->record_exists('enrol', array('courseid' => $data->courseid, 'enrol' => $this->get_name()))) {

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

        }

        // No need to set mapping, we do not restore users or roles here.

        $step->set_mapping('enrol', $oldid, 0);

    }

    /**

     * 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/guest: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);

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

            return false;

        }

        // If the instance is currently disabled, before it can be enabled, we must check whether the password meets the

        // password policies.

        if ($instance->status == ENROL_INSTANCE_DISABLED) {

            if ($this->get_config('requirepassword')) {

                if (empty($instance->password)) {

                    return false;

                }

            }

            // Only check the password if it is set.

            if (!empty($instance->password) && $this->get_config('usepasswordpolicy')) {

                if (!check_password_policy($instance->password, $errmsg)) {

                    return false;

                }

            }

        }

        return true;

    }

    /**

     * Get default settings for enrol_guest.

     *

     * @return array

     */

    public function get_instance_defaults() {

        $fields = array();

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

        return $fields;

    }

    /**

     * Return information for enrolment instance containing list of parameters required

     * for enrolment, name of enrolment plugin etc.

     *

     * @param stdClass $instance enrolment instance

     * @return stdClass instance info.

     * @since Moodle 3.1

     */

    public function get_enrol_info(stdClass $instance) {

        $instanceinfo = new stdClass();

        $instanceinfo->id = $instance->id;

        $instanceinfo->courseid = $instance->courseid;

        $instanceinfo->type = $this->get_name();

        $instanceinfo->name = $this->get_instance_name($instance);

        $instanceinfo->status = $instance->status == ENROL_INSTANCE_ENABLED;

        // Specifics enrolment method parameters.

        $instanceinfo->requiredparam = new stdClass();

        $instanceinfo->requiredparam->passwordrequired = !empty($instance->password);

        // If the plugin is enabled, return the URL for obtaining more information.

        if ($instanceinfo->status) {

            $instanceinfo->wsfunction = 'enrol_guest_get_instance_info';

        }

        return $instanceinfo;

    }

    /**

     * 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;

    }

    /**

     * 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) {

        global $CFG;

        $options = $this->get_status_options();

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

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

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

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

        $mform->addElement('passwordunmask', 'password', get_string('password', 'enrol_guest'));

        $mform->addHelpButton('password', 'password', 'enrol_guest');

        // If we have a new instance and the password is required - make sure it is set. For existing

        // instances we do not force the password to be required as it may have been set to empty before

        // the password was required. We check in the validation function whether this check is required

        // for existing instances.

        if (empty($instance->id) && $this->get_config('requirepassword')) {

            $mform->addRule('password', get_string('required'), 'required', null);

        }

    }

    /**

     * 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;

    }

    /**

     * 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();

        $checkpassword = false;

        if ($data['id']) {

            // Check the password if we are enabling the plugin again.

            if (($instance->status == ENROL_INSTANCE_DISABLED) && ($data['status'] == ENROL_INSTANCE_ENABLED)) {

                $checkpassword = true;

            }

            // Check the password if the instance is enabled and the password has changed.

            if (($data['status'] == ENROL_INSTANCE_ENABLED) && ($instance->password !== $data['password'])) {

                $checkpassword = true;

            }

        } else {

            $checkpassword = true;

        }

        if ($checkpassword) {

            $require = $this->get_config('requirepassword');

            $policy  = $this->get_config('usepasswordpolicy');

            if ($require && trim($data['password']) === '') {

                $errors['password'] = get_string('required');

            } else if (!empty($data['password']) && $policy) {

                $errmsg = '';

                if (!check_password_policy($data['password'], $errmsg)) {

                    $errors['password'] = $errmsg;

                }

            }

        }

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

        $tovalidate = array(

            'status' => $validstatus

        );

        $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 == 'guest') {

                // There can be only one guest 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 + ['password' => ''];

    }

    /**

     * Updates enrol plugin instance with provided data.

     * @param int $courseid Course ID.

     * @param array $enrolmentdata enrolment data.

     * @param stdClass $instance Instance to update.

     *

     * @return stdClass updated instance

     */

    public function update_enrol_plugin_data(int $courseid, array $enrolmentdata, stdClass $instance): stdClass {

        if (!empty($enrolmentdata['password'])) {

            $instance->password = $enrolmentdata['password'];

        }

        return parent::update_enrol_plugin_data($courseid, $enrolmentdata, $instance);

    }

    /**

     * Check if data is valid for a given enrolment plugin

     *

     * @param array $enrolmentdata enrolment data to validate.

     * @param int|null $courseid Course ID.

     * @return array Errors

     */

    public function validate_enrol_plugin_data(array $enrolmentdata, ?int $courseid = null): array {

        // If password is omitted or empty in csv it will be generated automatically if it is a required policy.

        $errors = parent::validate_enrol_plugin_data($enrolmentdata, $courseid);

        $policy = $this->get_config('usepasswordpolicy');

        if (!empty($enrolmentdata['password']) && $policy) {

            $errarray = get_password_policy_errors($enrolmentdata['password']);

            foreach ($errarray as $i => $err) {

                $errors['enrol_guest' . $i] = $err;

            }

        }

        return $errors;

    }

}

/**

 * Get icon mapping for font-awesome.

 */

function enrol_guest_get_fontawesome_icon_map() {

    return [

        'enrol_guest:withpassword' => 'fa-key',

        'enrol_guest:withoutpassword' => 'fa-unlock-alt',

    ];

}