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See Release Notes

  • Bug fixes for general core bugs in 4.2.x will end 22 April 2024 (12 months).
  • Bug fixes for security issues in 4.2.x will end 7 October 2024 (18 months).
  • PHP version: minimum PHP 8.0.0 Note: minimum PHP version has increased since Moodle 4.1. PHP 8.1.x is supported too.
<?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/>.

namespace qbank_customfields\customfield;

use core_customfield\api;
use core_customfield\field_controller;
use core_customfield\output\field_data;

/**
 * Question handler for custom fields.
 *
 * @package     qbank_customfields
 * @copyright   2021 Catalyst IT Australia Pty Ltd
 * @author      Matt Porritt <mattp@catalyst-au.net>
 * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
class question_handler extends \core_customfield\handler {

    /**
     * @var question_handler
     */
    static protected $singleton;

    /**
     * @var \context
     */
    protected $parentcontext;

    /** @var int Field is displayed in the question display and question preview, visible to everybody */
    const VISIBLETOALL = 2;
    /** @var int Field is displayed in the question display and question preview but only for "teachers" */
    const VISIBLETOTEACHERS = 1;
    /** @var int Field is not displayed in the question display and question preview */
    const NOTVISIBLE = 0;

    /**
     * Creates the custom field handler and returns a singleton.
     * Itemid is always zero as the custom fields are the same
     * for every question across the system.
     *
     * @param int $itemid Always zero.
     * @return \qbank_customfields\customfield\question_handler
     */
    public static function create(int $itemid = 0) : \core_customfield\handler {
        if (static::$singleton === null) {
            self::$singleton = new static(0);
        }
        return self::$singleton;
    }

    /**
     * Run reset code after unit tests to reset the singleton usage.
     */
    public static function reset_caches(): void {
        if (!PHPUNIT_TEST) {
            throw new \coding_exception('This feature is only intended for use in unit tests');
        }

        static::$singleton = null;
    }

    /**
     * The current user can configure custom fields on this component.
     *
     * @return bool true if the current can configure custom fields, false otherwise
     */
    public function can_configure() : bool {
        return has_capability('qbank/customfields:configurecustomfields', $this->get_configuration_context());
    }

    /**
     * The current user can edit custom fields for the given question.
     *
     * @param field_controller $field
     * @param int $instanceid id of the question to test edit permission
     * @return bool true if the current can edit custom fields, false otherwise
     */
    public function can_edit(field_controller $field, int $instanceid = 0) : bool {
        if ($instanceid) {
            $context = $this->get_instance_context($instanceid);
        } else {
            $context = $this->get_parent_context();
        }

        return (!$field->get_configdata_property('locked') ||
                has_capability('qbank/customfields:changelockedcustomfields', $context));
    }

    /**
     * The current user can view custom fields for the given question.
     *
     * @param field_controller $field
     * @param int $instanceid id of the question to test edit permission
     * @return bool true if the current can edit custom fields, false otherwise
     */
    public function can_view(field_controller $field, int $instanceid) : bool {
        $visibility = $field->get_configdata_property('visibility');
        if ($visibility == self::NOTVISIBLE) {
            return false;
        } else if ($visibility == self::VISIBLETOTEACHERS) {
            return has_capability('qbank/customfields:viewhiddencustomfields', $this->get_instance_context($instanceid));
        } else {
            return true;
        }
    }

    /**
     * Determine if the current user can view custom field in their given context.
     * This determines if the user can see the field at all not just the field for
     * a particular instance.
     * Used primarily in showing or not the field in the question bank table.
     *
     * @param field_controller $field The field trying to be viewed.
< * @param context $context The context the field is being displayed in.
> * @param \context $context The context the field is being displayed in.
* @return bool true if the current can edit custom fields, false otherwise. */ public function can_view_type(field_controller $field, \context $context) : bool { $visibility = $field->get_configdata_property('visibility'); if ($visibility == self::NOTVISIBLE) { return false; } else if ($visibility == self::VISIBLETOTEACHERS) { return has_capability('qbank/customfields:viewhiddencustomfields', $context); } else { return true; } } /** * Sets parent context for the question. * * This may be needed when question is being created, there is no question context but we need to check capabilities * * @param \context $context */ public function set_parent_context(\context $context): void { $this->parentcontext = $context; } /** * Returns the parent context for the question. * * @return \context */ protected function get_parent_context() : \context { if ($this->parentcontext) { return $this->parentcontext; } else { return \context_system::instance(); } } /** * Context that should be used for new categories created by this handler. * * @return \context the context for configuration */ public function get_configuration_context() : \context { return \context_system::instance(); } /** * URL for configuration page for the fields for the question custom fields. * * @return \moodle_url The URL to configure custom fields for this component */ public function get_configuration_url() : \moodle_url { return new \moodle_url('/question/customfield.php'); } /** * Returns the context for the data associated with the given instanceid. * * @param int $instanceid id of the record to get the context for * @return \context the context for the given record * @throws \coding_exception */ public function get_instance_context(int $instanceid = 0) : \context { if ($instanceid > 0) { $questiondata = \question_bank::load_question_data($instanceid); $contextid = $questiondata->contextid; $context = \context::instance_by_id($contextid); return $context; } else { throw new \coding_exception('Instance id must be provided.'); } } /** * Given a field and instance id get all the filed data. * * @param field_controller $field The field to get the data for. * @param int $instanceid The instance id to get the data for. * @return \core_customfield\data_controller The fetched data. */ public function get_field_data(\core_customfield\field_controller $field, int $instanceid): \core_customfield\data_controller { $fields = [$field->get('id') => $field]; $fieldsdata = api::get_instance_fields_data($fields, $instanceid); return $fieldsdata[$field->get('id')]; } /** * For a given instance id (question id) get the categories and the * fields with any data. Return an array of categories containing an * array of field names and values that is ready to be passed to a renderer. * * @param int $instanceid The instance id to get the data for. * @return array $cfdata The fetched data */ public function get_categories_fields_data(int $instanceid): array { // Prepare custom fields data. $instancedata = $this->get_instance_data($instanceid); $cfdata = []; foreach ($instancedata as $instance) { $field = $instance->get_field(); if ($this->can_view($field, $instanceid)) { $category = $instance->get_field()->get_category()->get('name'); $fieldname = $field->get_formatted_name(); $fieldvalue = $this->get_field_data($field, $instanceid)->export_value(); $cfdata[$category][] = ['name' => $fieldname, 'value' => $fieldvalue]; } } return $cfdata; } /** * Get the custom data for the given field * and render HTML ready for display in question table. * * @param object $fielddata The field data used for display. * @return string The HTML to display in the table column. */ public function display_custom_field_table(object $fielddata) : string { global $PAGE; $output = $PAGE->get_renderer('qbank_customfields'); $outputdata = new field_data($fielddata); return $output->render_for_table($outputdata); } /** * Render the custom field category and filed data as HTML ready for display. * * @param array $catfielddata Array of categories and field names and values. * @return string The HTML to display. */ public function display_custom_categories_fields(array $catfielddata) : string { global $PAGE; $output = $PAGE->get_renderer('qbank_customfields'); return $output->render_for_preview($catfielddata); } /** * Add custom controls to the field configuration form that will be saved. * * @param \MoodleQuickForm $mform The form to add the custom fields to. */ public function config_form_definition(\MoodleQuickForm $mform): void { $mform->addElement('header', 'question_handler_header', get_string('customfieldsettings', 'qbank_customfields')); $mform->setExpanded('question_handler_header', true); // If field is locked. $mform->addElement('selectyesno', 'configdata[locked]', get_string('customfield_islocked', 'qbank_customfields')); $mform->addHelpButton('configdata[locked]', 'customfield_islocked', 'qbank_customfields'); // Field data visibility. $visibilityoptions = [ self::VISIBLETOALL => get_string('customfield_visibletoall', 'qbank_customfields'), self::VISIBLETOTEACHERS => get_string('customfield_visibletoteachers', 'qbank_customfields'), self::NOTVISIBLE => get_string('customfield_notvisible', 'qbank_customfields') ]; $mform->addElement('select', 'configdata[visibility]', get_string('customfield_visibility', 'qbank_customfields'), $visibilityoptions); $mform->addHelpButton( 'configdata[visibility]', 'customfield_visibility', 'qbank_customfields'); } /** * Creates or updates the question custom field data when restoring from a backup. * * @param \restore_task $task * @param array $data */ public function restore_instance_data_from_backup(\restore_task $task, array $data): void { $editablefields = $this->get_editable_fields($data['newquestion']); $records = api::get_instance_fields_data($editablefields, $data['newquestion']); $target = $task->get_target(); $override = ($target != \backup::TARGET_CURRENT_ADDING && $target != \backup::TARGET_EXISTING_ADDING); foreach ($records as $d) { $field = $d->get_field(); if ($field->get('shortname') === $data['shortname'] && $field->get('type') === $data['type']) { if (!$d->get('id') || $override) { $d->set($d->datafield(), $data['value']); $d->set('value', $data['value']); $d->set('valueformat', $data['valueformat']); $d->set('contextid', $data['fieldcontextid']); $d->save(); } return; } } } }