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Source/Editor/GUI/Timeline/Undo/EditTimelineAction.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+using System.IO;
+
+namespace FlaxEditor.GUI.Timeline.Undo
+{
+    class EditTimelineAction : IUndoAction
+    {
+        private Timeline _timeline;
+        private byte[] _beforeData;
+        private byte[] _afterData;
+
+        public EditTimelineAction(Timeline timeline, byte[] beforeData, byte[] afterData)
+        {
+            _timeline = timeline;
+            _beforeData = beforeData;
+            _afterData = afterData;
+        }
+
+        public static byte[] CaptureData(Timeline timeline)
+        {
+            using (var memory = new MemoryStream(512))
+            using (var stream = new BinaryWriter(memory))
+            {
+                stream.Write(timeline.DurationFrames);
+                return memory.ToArray();
+            }
+        }
+
+        private void Set(byte[] data)
+        {
+            using (var memory = new MemoryStream(data))
+            using (var stream = new BinaryReader(memory))
+            {
+                _timeline.DurationFrames = stream.ReadInt32();
+            }
+            _timeline.ArrangeTracks();
+            _timeline.MarkAsEdited();
+        }
+
+        public string ActionString => "Edit timeline";
+
+        public void Do()
+        {
+            Set(_afterData);
+        }
+
+        public void Undo()
+        {
+            Set(_beforeData);
+        }
+
+        public void Dispose()
+        {
+            _timeline = null;
+            _beforeData = null;
+            _afterData = null;
+        }
+    }
+}