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Source/Editor/Undo/UndoActionBase.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+using System;
+using FlaxEditor.SceneGraph;
+using FlaxEngine;
+using Newtonsoft.Json;
+using JsonSerializer = FlaxEngine.Json.JsonSerializer;
+
+namespace FlaxEditor
+{
+    internal class SceneTreeNodeConverter : JsonConverter
+    {
+        /// <inheritdoc />
+        public override void WriteJson(JsonWriter writer, object value, Newtonsoft.Json.JsonSerializer serializer)
+        {
+            Guid id = Guid.Empty;
+            if (value is SceneGraphNode obj)
+                id = obj.ID;
+
+            writer.WriteValue(id.ToString("N"));
+        }
+
+        /// <inheritdoc />
+        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, Newtonsoft.Json.JsonSerializer serializer)
+        {
+            if (reader.TokenType == JsonToken.String)
+            {
+                var id = Guid.Parse((string)reader.Value);
+                return SceneGraphFactory.FindNode(id);
+            }
+
+            return null;
+        }
+
+        /// <inheritdoc />
+        public override bool CanConvert(Type objectType)
+        {
+            return typeof(SceneGraphNode).IsAssignableFrom(objectType);
+        }
+    }
+
+    /// <summary>
+    /// Base class for <see cref="IUndoAction"/> implementations. Stores undo data serialized and preserves references to the game objects.
+    /// </summary>
+    /// <typeparam name="TData">The type of the data. Must have <see cref="SerializableAttribute"/>.</typeparam>
+    /// <seealso cref="FlaxEditor.IUndoAction" />
+    [Serializable]
+    public abstract class UndoActionBase<TData> : IUndoAction where TData : struct
+    {
+        /// <summary>
+        /// The serialized data (Json text).
+        /// </summary>
+        [Serialize]
+        protected string _data;
+
+        /// <summary>
+        /// Gets or sets the serialized undo data.
+        /// </summary>
+        /// <value>
+        /// The data.
+        /// </value>
+        [NoSerialize]
+        public TData Data
+        {
+            get => JsonConvert.DeserializeObject<TData>(_data, JsonSerializer.Settings);
+            protected set => _data = JsonConvert.SerializeObject(value, Formatting.None, JsonSerializer.Settings);
+            /*protected set
+            {
+                _data = JsonConvert.SerializeObject(value, Formatting.Indented, JsonSerializer.Settings);
+                Debug.Info(_data);
+            }*/
+        }
+
+        /// <inheritdoc />
+        public abstract string ActionString { get; }
+
+        /// <inheritdoc />
+        public abstract void Do();
+
+        /// <inheritdoc />
+        public abstract void Undo();
+
+        /// <inheritdoc />
+        public virtual void Dispose()
+        {
+            _data = null;
+        }
+    }
+}