add dark mode base configuration

Application/Core/TinyMCE/Configuration.php

@@ -45,6 +45,7 @@ use O3\TinyMCE\Application\Core\TinyMCE\Options\QuickbarsInsertToolbar;
 use O3\TinyMCE\Application\Core\TinyMCE\Options\RelativeUrls;
 use O3\TinyMCE\Application\Core\TinyMCE\Options\Selector;
 use O3\TinyMCE\Application\Core\TinyMCE\Options\Setup;
+use O3\TinyMCE\Application\Core\TinyMCE\Options\Skin;
 use O3\TinyMCE\Application\Core\TinyMCE\Options\Toolbar;
 use O3\TinyMCE\Application\Core\TinyMCE\Options\ToolbarMode;
 use O3\TinyMCE\Application\Core\TinyMCE\Options\ToolbarSticky;
@@ -106,6 +107,7 @@ class Configuration
 
     protected function addGuiOptions(): void
     {
+        $this->addOption(oxNew(Skin::class, $this->loader));
         $this->addOption(oxNew(Promotion::class, $this->loader));
         $this->addOption(oxNew(ContextMenu::class, $this->loader));
         $this->addOption(oxNew(MinHeight::class, $this->loader));

Application/Core/TinyMCE/Options/ContentCss.php

@@ -32,9 +32,18 @@ class ContentCss extends AbstractOption
 
     protected Loader $loader;
 
+    protected bool $darkMode = false;
+
     public function get(): string
     {
-        return '/out/'.strtolower(Registry::getConfig()->getConfigParam('sTheme')).'/src/css/styles.min.css';
+        return implode(
+            ',',
+            [
+                $this->darkMode ?
+                    'dark' :
+                    '/out/'.strtolower(Registry::getConfig()->getConfigParam('sTheme')).'/src/css/styles.min.css'
+            ]
+        );
     }
 
     public function mustQuote(): bool

Application/Core/TinyMCE/Options/Skin.php

@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * This file is part of O3-Shop TinyMCE editor module.
+ *
+ * This program 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, version 3.
+ *
+ * This program 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 O3-Shop.  If not, see <http://www.gnu.org/licenses/>
+ *
+ * @copyright  Copyright (c) 2022 Marat Bedoev, bestlife AG
+ * @copyright  Copyright (c) 2023 O3-Shop (https://www.o3-shop.com)
+ * @license    https://www.gnu.org/licenses/gpl-3.0  GNU General Public License 3 (GPLv3)
+ */
+
+declare(strict_types=1);
+
+namespace O3\TinyMCE\Application\Core\TinyMCE\Options;
+
+use O3\TinyMCE\Application\Core\TinyMCE\Loader;
+use OxidEsales\Eshop\Core\Registry;
+use OxidEsales\Eshop\Core\UtilsServer;
+
+class Skin extends AbstractOption
+{
+    protected string $key = 'skin';
+
+    protected Loader $loader;
+
+    protected bool $darkMode = false;
+
+    public function get(): string
+    {
+        return $this->darkMode ? 'oxide-dark' : 'oxide';
+    }
+
+    public function mustQuote(): bool
+    {
+        return true;
+    }
+}