From cc8fe8c269a7f8441375432b996792072fe3a9e7 Mon Sep 17 00:00:00 2001
From: sbosse <sbosse@uni-bremen.de>
Date: Mon, 21 Jul 2025 23:39:54 +0200
Subject: [PATCH] Mon 21 Jul 22:43:21 CEST 2025

---
 js/ui/mxgraph/src/js/io/mxRootChangeCodec.js | 83 ++++++++++++++++++++
 1 file changed, 83 insertions(+)
 create mode 100644 js/ui/mxgraph/src/js/io/mxRootChangeCodec.js

diff --git a/js/ui/mxgraph/src/js/io/mxRootChangeCodec.js b/js/ui/mxgraph/src/js/io/mxRootChangeCodec.js
new file mode 100644
index 0000000..bf8c47d
--- /dev/null
+++ b/js/ui/mxgraph/src/js/io/mxRootChangeCodec.js
@@ -0,0 +1,83 @@
+/**
+ * Copyright (c) 2006-2015, JGraph Ltd
+ * Copyright (c) 2006-2015, Gaudenz Alder
+ */
+mxCodecRegistry.register(function()
+{
+	/**
+	 * Class: mxRootChangeCodec
+	 *
+	 * Codec for <mxRootChange>s. This class is created and registered
+	 * dynamically at load time and used implicitely via <mxCodec> and
+	 * the <mxCodecRegistry>.
+	 *
+	 * Transient Fields:
+	 *
+	 * - model
+	 * - previous
+	 * - root
+	 */
+	var codec = new mxObjectCodec(new mxRootChange(),
+		['model', 'previous', 'root']);
+
+	/**
+	 * Function: onEncode
+	 *
+	 * Encodes the child recursively.
+	 */
+	codec.afterEncode = function(enc, obj, node)
+	{
+		enc.encodeCell(obj.root, node);
+		
+		return node;
+	};
+
+	/**
+	 * Function: beforeDecode
+	 *
+	 * Decodes the optional children as cells
+	 * using the respective decoder.
+	 */
+	codec.beforeDecode = function(dec, node, obj)
+	{
+		if (node.firstChild != null &&
+			node.firstChild.nodeType == mxConstants.NODETYPE_ELEMENT)
+		{
+			// Makes sure the original node isn't modified
+			node = node.cloneNode(true);
+			
+			var tmp = node.firstChild;
+			obj.root = dec.decodeCell(tmp, false);
+
+			var tmp2 = tmp.nextSibling;
+			tmp.parentNode.removeChild(tmp);
+			tmp = tmp2;
+		
+			while (tmp != null)
+			{
+				tmp2 = tmp.nextSibling;
+				dec.decodeCell(tmp);
+				tmp.parentNode.removeChild(tmp);
+				tmp = tmp2;
+			}
+		}
+		
+		return node;
+	};
+	
+	/**
+	 * Function: afterDecode
+	 *
+	 * Restores the state by assigning the previous value.
+	 */
+	codec.afterDecode = function(dec, node, obj)
+	{
+		obj.previous = obj.root;
+		
+		return obj;
+	};
+
+	// Returns the codec into the registry
+	return codec;
+
+}());