refactor: documents interfaces

Signed-off-by: Sebastian Krupinski <krupinski01@gmail.com>

shared/lib/Documents/Collection/CollectionPropertiesBaseAbstract.php

@@ -0,0 +1,42 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: Sebastian Krupinski <krupinski01@gmail.com>
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace KTXF\Documents\Collection;
+
+use KTXF\Resource\Provider\Node\NodePropertiesBaseAbstract;
+
+/**
+ * Abstract Collection Properties Base Class
+ * 
+ * Provides common implementation for collection properties
+ * 
+ * @since 2025.05.01
+ */
+abstract class CollectionPropertiesBaseAbstract extends NodePropertiesBaseAbstract implements CollectionPropertiesBaseInterface {
+
+    public const JSON_TYPE = CollectionPropertiesBaseInterface::JSON_TYPE;
+
+    public function content(): CollectionContent {
+        $content = $this->data[self::PROPERTY_CONTENTS] ?? null;
+        if ($content instanceof CollectionContent) {
+            return $content;
+        }
+
+        if (is_string($content)) {
+            return CollectionContent::tryFrom($content) ?? CollectionContent::File;
+        }
+
+        return CollectionContent::File;
+    }
+
+    public function getLabel(): string {
+        return $this->data[self::PROPERTY_LABEL] ?? '';
+    }
+
+}