From c751d131685ee8ea22e64470d2a726cbcf757592 Mon Sep 17 00:00:00 2001
From: Matthias Schmidt <gravatronics@live.com>
Date: Sun, 20 Dec 2020 10:44:51 +0100
Subject: [PATCH] Add `TCssClassFormField`

---
 .../field/TCssClassFormField.class.php        | 93 +++++++++++++++++++
 1 file changed, 93 insertions(+)
 create mode 100644 wcfsetup/install/files/lib/system/form/builder/field/TCssClassFormField.class.php

diff --git a/wcfsetup/install/files/lib/system/form/builder/field/TCssClassFormField.class.php b/wcfsetup/install/files/lib/system/form/builder/field/TCssClassFormField.class.php
new file mode 100644
index 0000000000..69f5c9ce1c
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/form/builder/field/TCssClassFormField.class.php
@@ -0,0 +1,93 @@
+<?php
+namespace wcf\system\form\builder\field;
+use wcf\system\form\builder\TFormNode;
+
+/**
+ * Provides default implementations of `ICssClassFormField` methods.
+ *
+ * @author      Matthias Schmidt
+ * @copyright   2001-2020 WoltLab GmbH
+ * @license     GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @package     WoltLabSuite\Core\System\Form\Builder\Field
+ * @since       5.4
+ */
+trait TCssClassFormField {
+	/**
+	 * CSS classes of this node
+	 * @var string[]
+	 */
+	protected $fieldClasses = [];
+	
+	/**
+	 * Adds the given CSS class to the actual field element and returns this field.
+	 *
+	 * @throws      \InvalidArgumentException       if the given class is invalid
+	 */
+	public function addFieldClass(string $class): self {
+		static::validateClass($class);
+		
+		if (!in_array($class, $this->fieldClasses)) {
+			$this->fieldClasses[] = $class;
+		}
+		
+		return $this;
+	}
+	
+	/**
+	 * Adds the given CSS classes to the actual field element and returns this field.
+	 *
+	 * @throws      \InvalidArgumentException       if any of the given classes is invalid
+	 */
+	public function addFieldClasses(array $classes): self {
+		foreach ($classes as $class) {
+			$this->addFieldClass($class);
+		}
+		
+		return $this;
+	}
+	
+	/**
+	 * Returns all CSS classes of the actual field element.
+	 */
+	public function getFieldClasses(): array {
+		return $this->fieldClasses;
+	}
+	
+	/**
+	 * Returns `true` if a CSS class of the actual field element with the given name exists and returns `false` otherwise.
+	 *
+	 * @throws      \InvalidArgumentException       if the given class is invalid
+	 */
+	public function hasFieldClass(string $class): bool {
+		static::validateClass($class);
+		
+		return array_search($class, $this->fieldClasses) !== false;
+	}
+	
+	/**
+	 * Removes the given CSS class of the actual field element and returns this field.
+	 *
+	 * If the actual field element does not have the given CSS class, this method silently ignores that fact.
+	 *
+	 * @throws      \InvalidArgumentException       if the given class is invalid
+	 */
+	public function removeFieldClass(string $class): self {
+		static::validateClass($class);
+		
+		$index = array_search($class, $this->fieldClasses);
+		if ($index !== false) {
+			unset($this->fieldClasses[$index]);
+		}
+		
+		return $this;
+	}
+	
+	/**
+	 * Checks if the given parameter class is a valid CSS class.
+	 *
+	 * @param       string          $class          checked class
+	 *
+	 * @throws      \InvalidArgumentException       if the given class is invalid
+	 */
+	abstract public static function validateClass($class);
+}
-- 
2.20.1