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/>.

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.

     * @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

     *

     * @return int|void Conditionally returns the ID of the created or updated record.

     */

    public function restore_instance_data_from_backup(\restore_task $task, array $data) {

        $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']);

                    $d->set('valuetrust', !empty($data['valuetrust']));

                    $d->set('contextid', $data['fieldcontextid']);

                    $d->save();

                }

                return $d->get('id');

            }

        }

    }

}