Sindbad~EG File Manager

<?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/>.

/**
 * Amanote configuration form.
 *
 * @package     mod_amanote
 * @copyright   2018 Amaplex Software
 * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

defined('MOODLE_INTERNAL') || die;

require_once($CFG->dirroot.'/course/moodleform_mod.php');
require_once($CFG->dirroot.'/mod/amanote/locallib.php');
require_once($CFG->libdir.'/filelib.php');

/**
 * Amanote settings form.
 *
 * @package     mod_amanote
 * @copyright   2018 Amaplex Software
 * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
class mod_amanote_mod_form extends moodleform_mod {

    /**
     * Defines forms elements.
     */
    public function definition() {
        global $CFG, $DB;
        $mform =& $this->_form;

        $config = get_config('mod_amanote');

        // General section.
        $mform->addElement('header', 'general', get_string('general', 'form'));
        // Resource name.
        $mform->addElement('text', 'name', get_string('name'), array('size' => '48'));
        if (!empty($CFG->formatstringstriptags)) {
            $mform->setType('name', PARAM_TEXT);
        } else {
            $mform->setType('name', PARAM_CLEANHTML);
        }
        $mform->addRule('name', null, 'required', null, 'client');
        $mform->addRule('name', get_string('maximumchars', '', 255), 'maxlength', 255, 'client');

        // Resource description.
        $this->standard_intro_elements();
        $element = $mform->getElement('introeditor');
        $attributes = $element->getAttributes();
        $attributes['rows'] = 5;
        $element->setAttributes($attributes);

        // Resource file manager.
        $filemanageroptions = array();
        $filemanageroptions['accepted_types'] = array(
            'application/pdf',
            'application/vnd.ms-powerpoint',
            'application/vnd.openxmlformats-officedocument.presentationml.presentation'
        );
        $filemanageroptions['maxbytes'] = 0;
        $filemanageroptions['maxfiles'] = 1;
        $filemanageroptions['subdirs'] = 0;
        $mform->addElement('filemanager', 'files', get_string('selectfiles'), null, $filemanageroptions);

        // Appearance section.
        $mform->addElement('header', 'optionssection', get_string('appearance'));

        $mform->addElement('checkbox', 'showsize', get_string('showsize', 'amanote'));
        $mform->setDefault('showsize', $config->showsize);
        $mform->addHelpButton('showsize', 'showsize', 'amanote');
        $mform->addElement('checkbox', 'showdate', get_string('showdate', 'amanote'));
        $mform->setDefault('showdate', $config->showdate);
        $mform->addHelpButton('showdate', 'showdate', 'amanote');

        // Common sections.
        $this->standard_coursemodule_elements();

        // Common buttons.
        $this->add_action_buttons();

        // Add hidden element revision.
        $mform->addElement('hidden', 'revision');
        $mform->setType('revision', PARAM_INT);
        $mform->setDefault('revision', 1);
    }

    /**
     * Form data preprocessor.
     *
     * @param array $defaultvalues passed by reference
     */
    public function data_preprocessing(&$defaultvalues) {
        if ($this->current->instance) {
            $draftitemid = file_get_submitted_draft_itemid('files');
            file_prepare_draft_area($draftitemid, $this->context->id, 'mod_amanote', 'content', 0, array('subdirs' => true));
            $defaultvalues['files'] = $draftitemid;
        }
        if (!empty($defaultvalues['displayoptions'])) {
            $displayoptions = unserialize($defaultvalues['displayoptions']);
            if (isset($displayoptions['printintro'])) {
                $defaultvalues['printintro'] = $displayoptions['printintro'];
            }
            if (!empty($displayoptions['showsize'])) {
                $defaultvalues['showsize'] = $displayoptions['showsize'];
            } else {
                // Must set explicitly to 0 here otherwise it will use system
                // default which may be 1.
                $defaultvalues['showsize'] = 0;
            }
            if (!empty($displayoptions['showdate'])) {
                $defaultvalues['showdate'] = $displayoptions['showdate'];
            } else {
                $defaultvalues['showdate'] = 0;
            }
        }
    }

    /**
     * Validate the data.
     *
     * @param array $data array of ("fieldname"=>value) of submitted data
     * @param array $files array of uploaded files "element_name"=>tmp_file_path
     * @return array of "element_name"=>"error_description" if there are errors,
     *         or an empty array if everything is OK (true allowed for backwards compatibility too).
     */
    public function validation($data, $files) {
        global $USER;

        $errors = parent::validation($data, $files);

        $usercontext = context_user::instance($USER->id);
        $fs = get_file_storage();
        if (!$files = $fs->get_area_files($usercontext->id, 'user', 'draft', $data['files'], 'sortorder, id', false)) {
            $errors['files'] = get_string('required');
            return $errors;
        }

        return $errors;
    }
}