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Source/Editor/Surface/Undo/BoxHandle.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+using System;
+using FlaxEditor.Surface.Elements;
+using FlaxEngine;
+
+namespace FlaxEditor.Surface.Undo
+{
+    /// <summary>
+    /// The helper structure for Surface node box handle.
+    /// </summary>
+    [HideInEditor]
+    public struct BoxHandle
+    {
+        private readonly uint _nodeId;
+        private readonly int _boxId;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="BoxHandle"/> struct.
+        /// </summary>
+        /// <param name="nodeId">The node identifier.</param>
+        /// <param name="boxId">The box identifier.</param>
+        public BoxHandle(uint nodeId, int boxId)
+        {
+            _nodeId = nodeId;
+            _boxId = boxId;
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="BoxHandle"/> struct.
+        /// </summary>
+        /// <param name="box">The box.</param>
+        public BoxHandle(Box box)
+        {
+            _nodeId = box.ParentNode.ID;
+            _boxId = box.ID;
+        }
+
+        /// <summary>
+        /// Gets the box.
+        /// </summary>
+        /// <param name="context">The Surface context.</param>
+        /// <returns>The restored box.</returns>
+        public Box Get(VisjectSurfaceContext context)
+        {
+            var node = context.FindNode(_nodeId);
+            if (node == null)
+                throw new Exception("Missing node.");
+            var box = node.GetBox(_boxId);
+            if (box == null)
+                throw new Exception("Missing box.");
+            return box;
+        }
+    }
+}