From bd2fa2bef54571c593122a4cbf6713f37cc68e12 Mon Sep 17 00:00:00 2001
From: sbosse <sbosse@uni-bremen.de>
Date: Mon, 21 Jul 2025 23:40:04 +0200
Subject: [PATCH] Mon 21 Jul 22:43:21 CEST 2025

---
 .../mxgraph/src/js/io/mxGenericChangeCodec.js | 64 +++++++++++++++++++
 1 file changed, 64 insertions(+)
 create mode 100644 js/ui/mxgraph/src/js/io/mxGenericChangeCodec.js

diff --git a/js/ui/mxgraph/src/js/io/mxGenericChangeCodec.js b/js/ui/mxgraph/src/js/io/mxGenericChangeCodec.js
new file mode 100644
index 0000000..8ecc82a
--- /dev/null
+++ b/js/ui/mxgraph/src/js/io/mxGenericChangeCodec.js
@@ -0,0 +1,64 @@
+/**
+ * Copyright (c) 2006-2015, JGraph Ltd
+ * Copyright (c) 2006-2015, Gaudenz Alder
+ */
+/**
+ * Class: mxGenericChangeCodec
+ *
+ * Codec for <mxValueChange>s, <mxStyleChange>s, <mxGeometryChange>s,
+ * <mxCollapseChange>s and <mxVisibleChange>s. This class is created
+ * and registered dynamically at load time and used implicitely
+ * via <mxCodec> and the <mxCodecRegistry>.
+ *
+ * Transient Fields:
+ *
+ * - model
+ * - previous
+ *
+ * Reference Fields:
+ *
+ * - cell
+ * 
+ * Constructor: mxGenericChangeCodec
+ *
+ * Factory function that creates a <mxObjectCodec> for
+ * the specified change and fieldname.
+ *
+ * Parameters:
+ *
+ * obj - An instance of the change object.
+ * variable - The fieldname for the change data.
+ */
+var mxGenericChangeCodec = function(obj, variable)
+{
+	var codec = new mxObjectCodec(obj,  ['model', 'previous'], ['cell']);
+
+	/**
+	 * Function: afterDecode
+	 *
+	 * Restores the state by assigning the previous value.
+	 */
+	codec.afterDecode = function(dec, node, obj)
+	{
+		// Allows forward references in sessions. This is a workaround
+		// for the sequence of edits in mxGraph.moveCells and cellsAdded.
+		if (mxUtils.isNode(obj.cell))
+		{
+			obj.cell = dec.decodeCell(obj.cell, false);
+		}
+
+		obj.previous = obj[variable];
+
+		return obj;
+	};
+	
+	return codec;
+};
+
+// Registers the codecs
+mxCodecRegistry.register(mxGenericChangeCodec(new mxValueChange(), 'value'));
+mxCodecRegistry.register(mxGenericChangeCodec(new mxStyleChange(), 'style'));
+mxCodecRegistry.register(mxGenericChangeCodec(new mxGeometryChange(), 'geometry'));
+mxCodecRegistry.register(mxGenericChangeCodec(new mxCollapseChange(), 'collapsed'));
+mxCodecRegistry.register(mxGenericChangeCodec(new mxVisibleChange(), 'visible'));
+mxCodecRegistry.register(mxGenericChangeCodec(new mxCellAttributeChange(), 'value'));