MDL-57898 core_customfield: Custom fields API

This commit is part of work on Custom fields API,
to minimize commit history in moodle core the work of a team of developers was split
into several commits with different authors but the authorship of individual
lines of code may be different from the commit author.

customfield/classes/field_config_form.php

@@ -0,0 +1,134 @@
+<?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/>.
+
+/**
+ * Customfield package
+ *
+ * @package   core_customfield
+ * @copyright 2018 David Matamoros <davidmc@moodle.com>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core_customfield;
+
+defined('MOODLE_INTERNAL') || die;
+
+global $CFG;
+require_once($CFG->libdir . '/formslib.php');
+
+/**
+ * Class field_config_form
+ *
+ * @package core_customfield
+ * @copyright 2018 David Matamoros <davidmc@moodle.com>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class field_config_form extends \moodleform {
+
+    /**
+     * Class definition
+     *
+     * @throws \coding_exception
+     */
+    public function definition() {
+        global $PAGE;
+        $mform = $this->_form;
+
+        $field = $this->_customdata['field'];
+        if (!($field && $field instanceof field_controller)) {
+            throw new \coding_exception('Field must be passed in customdata');
+        }
+        $handler = $field->get_handler();
+
+        $mform->addElement('header', '_commonsettings', get_string('commonsettings', 'core_customfield'));
+
+        $mform->addElement('text', 'name', get_string('fieldname', 'core_customfield'), 'size="50"');
+        $mform->addRule('name', null, 'required', null, 'client');
+        $mform->setType('name', PARAM_TEXT);
+
+        // Accepted values for 'shortname' would follow [a-z0-9_] pattern,
+        // but we are accepting any PARAM_TEXT value here,
+        // and checking [a-zA-Z0-9_] pattern in validation() function to throw an error when needed.
+        $mform->addElement('text', 'shortname', get_string('fieldshortname', 'core_customfield'), 'size=20');
+        $mform->addHelpButton('shortname', 'shortname', 'core_customfield');
+        $mform->addRule('shortname', null, 'required', null, 'client');
+        $mform->setType('shortname', PARAM_TEXT);
+
+        $desceditoroptions = $handler->get_description_text_options();
+        $mform->addElement('editor', 'description_editor', get_string('description', 'core_customfield'), null, $desceditoroptions);
+        $mform->addHelpButton('description_editor', 'description', 'core_customfield');
+
+        // If field is required.
+        $mform->addElement('selectyesno', 'configdata[required]', get_string('isfieldrequired', 'core_customfield'));
+        $mform->addHelpButton('configdata[required]', 'isfieldrequired', 'core_customfield');
+        $mform->setType('configdata[required]', PARAM_BOOL);
+
+        // If field data is unique.
+        $mform->addElement('selectyesno', 'configdata[uniquevalues]', get_string('isdataunique', 'core_customfield'));
+        $mform->addHelpButton('configdata[uniquevalues]', 'isdataunique', 'core_customfield');
+        $mform->setType('configdata[uniquevalues]', PARAM_BOOL);
+
+        // Field specific settings from field type.
+        $field->config_form_definition($mform);
+
+        // Handler/component settings.
+        $handler->config_form_definition($mform);
+
+        // We add hidden fields.
+        $mform->addElement('hidden', 'categoryid');
+        $mform->setType('categoryid', PARAM_INT);
+
+        $mform->addElement('hidden', 'type');
+        $mform->setType('type', PARAM_COMPONENT);
+
+        $mform->addElement('hidden', 'id');
+        $mform->setType('id', PARAM_INT);
+
+        $this->add_action_buttons(true);
+    }
+
+    /**
+     * Field data validation
+     *
+     * @param array $data
+     * @param array $files
+     * @return array
+     */
+    public function validation($data, $files = array()) {
+        global $DB;
+
+        $errors = array();
+        /** @var field_controller $field */
+        $field = $this->_customdata['field'];
+        $handler = $field->get_handler();
+
+        // Check the shortname is specified and is unique for this component-area-itemid combination.
+        if (!preg_match('/^[a-z0-9_]+$/', $data['shortname'])) {
+            // Check allowed pattern (numbers, letters and underscore).
+            $errors['shortname'] = get_string('invalidshortnameerror', 'core_customfield');
+        } else if ($DB->record_exists_sql('SELECT 1 FROM {customfield_field} f ' .
+            'JOIN {customfield_category} c ON c.id = f.categoryid ' .
+            'WHERE f.shortname = ? AND f.id <> ? AND c.component = ? AND c.area = ? AND c.itemid = ?',
+            [$data['shortname'], $data['id'],
+                $handler->get_component(), $handler->get_area(), $handler->get_itemid()])) {
+            $errors['shortname'] = get_string('formfieldcheckshortname', 'core_customfield');
+        }
+
+        $errors = array_merge($errors, $field->config_form_validation($data, $files));
+
+        return $errors;
+    }
+}