Added more patch classes: replace and insert as sibling

UIExtenderLib/Prefab/Patches.cs

@@ -9,11 +9,17 @@ public interface IPrefabPatch
     {
     }
 
+    /**
+     * Custom patch on either whole XmlDocument (if T is XmlDocument) or Xpath specified node (if XmlNode is the generic argument)
+     */
     public abstract class CustomPatch<T> : IPrefabPatch where T: XmlNode
     {
         public abstract void Apply(T document);
     }
 
+    /**
+     * Base class for insert patches
+     */
     public abstract class InsertPatch : IPrefabPatch
     {
         public static int PositionFirst = 0;
@@ -22,8 +28,35 @@ public abstract class InsertPatch : IPrefabPatch
         public abstract int Position { get; }
     }
 
+    /**
+     * Patch that inserts prefab extension (specified by `Name`) as a child in XPath specified node, at specific position (`Position` property)
+     */
     public abstract class PrefabExtensionInsertPatch: InsertPatch
     {
         public abstract string Name { get; }
     }
+
+    /**
+     * Patch that replaces node specified by XPath with node from prefab extension
+     */
+    public abstract class PrefabExtensionReplacePatch : IPrefabPatch
+    {
+        public abstract string Name { get; }
+    }
+
+    /**
+     * Patch that inserts prefab extension as a sibling to node specified by Xpath.
+     * Order is controlled by `Type` property.
+     */
+    public abstract class PrefabExtensionInsertAsSiblingPatch
+    {
+        public enum InsertType
+        {
+            Prepend,
+            Append,
+        }
+
+        public virtual InsertType Type => InsertType.Append;
+        public abstract string Name { get; }
+    }
 }

UIExtenderLibModule/Prefab/PrefabComponent.cs

@@ -27,7 +27,7 @@ internal class PrefabComponent
         internal void RegisterPatch(string movie, Action<XmlDocument> patcher)
         {
             Debug.Assert(movie != null && !movie.IsEmpty(), $"Invalid movie name: {movie}!");
-            
+
             _moviePatches.Get(movie, () => new List<Action<XmlDocument>>()).Add(patcher);
         }
 
@@ -50,36 +50,61 @@ internal void RegisterPatch(string movie, string xpath, Action<XmlNode> patcher)
         }
 
         /**
-         * Register Gauntlet movie XML insert patch.
+         * Register XML insert patch
          */
         internal void RegisterPatch(string movie, string xpath, PrefabExtensionInsertPatch patch)
         {
             Debug.Assert(_prefabExtensionPaths.ContainsKey(patch.Name), $"Prefab extension with name {patch.Name} does not exist!");
 
             RegisterPatch(movie, xpath, (node) =>
             {
-                var path = _prefabExtensionPaths[patch.Name];
-                var doc = new XmlDocument();
-
-                using (var reader = XmlReader.Create(path, new XmlReaderSettings
-                {
-                    IgnoreComments = true,
-                    IgnoreWhitespace = true,
-                }))
-                {
-                    doc.Load(reader);
-                }
-
-                Debug.Assert(doc.HasChildNodes, $"Failed to parse extension ({patch.Name}) XML!");
-                var newNode = node.OwnerDocument.ImportNode(doc.DocumentElement, true);
+                var extensionNode = LoadPrefabExtension(patch.Name);
+                var importedExtensionNode = node.OwnerDocument.ImportNode(extensionNode, true);
                 var position = Math.Min(patch.Position, node.ChildNodes.Count - 1);
                 position = Math.Max(position, 0);
                 Debug.Assert(position >= 0 && position < node.ChildNodes.Count, $"Invalid position ({position}) for insert (patching in {patch.Name})");
 
-                node.InsertAfter(newNode, node.ChildNodes[position]);
+                node.InsertAfter(importedExtensionNode, node.ChildNodes[position]);
+            });
+        }
+
+        /**
+         * Register XML replace patch
+         */
+        internal void RegisterPatch(string movie, string xpath, PrefabExtensionReplacePatch patch)
+        {
+            RegisterPatch(movie, xpath, (node) =>
+            {
+                var extensionNode = LoadPrefabExtension(patch.Name);
+                var importedExtensionNode = node.OwnerDocument.ImportNode(extensionNode, true);
+
+                node.ParentNode.ReplaceChild(importedExtensionNode, node);
             });
         }
 
+        /**
+         * Register XML sibling insert patch
+         */
+        internal void RegisterPatch(string movie, string xpath, PrefabExtensionInsertAsSiblingPatch patch)
+        {
+            RegisterPatch(movie, xpath, (node) =>
+            {
+                var extensionNode = LoadPrefabExtension(patch.Name);
+                var importedExtensionNode = node.OwnerDocument.ImportNode(extensionNode, true);
+
+                switch (patch.Type)
+                {
+                    case PrefabExtensionInsertAsSiblingPatch.InsertType.Append:
+                        node.ParentNode.InsertAfter(importedExtensionNode, node);
+                        break;
+
+                    case PrefabExtensionInsertAsSiblingPatch.InsertType.Prepend:
+                        node.ParentNode.InsertBefore(importedExtensionNode, node);
+                        break;
+                }
+            });           
+        }
+
         /**
          * Search loaded modules for PrefabExtensions and save them for further reference
          */
@@ -101,6 +126,27 @@ internal void FindPrefabExtensions()
             }
         }
 
+        /**
+         * Load and parse prefab extension
+         */
+        private XmlNode LoadPrefabExtension(string name)
+        {
+            var path = _prefabExtensionPaths[name];
+            var doc = new XmlDocument();
+
+            using (var reader = XmlReader.Create(path, new XmlReaderSettings
+            {
+                IgnoreComments = true,
+                IgnoreWhitespace = true,
+            }))
+            {
+                doc.Load(reader);
+            }
+
+            Debug.Assert(doc.HasChildNodes, $"Failed to parse extension ({name}) XML!");
+            return doc.DocumentElement;
+        }
+
         /**
          * Make WidgetFactory reload Movies that were extended by _moviePatches.
          * 

UIExtenderLibModule/UIExtenderLibModule.cs

@@ -46,6 +46,14 @@ protected override void OnBeforeInitialModuleScreenSetAsRoot()
                             WidgetComponent.RegisterPatch(xmlExtension.Movie, xmlExtension.XPath, patch);
                             break;
 
+                        case PrefabExtensionReplacePatch patch:
+                            WidgetComponent.RegisterPatch(xmlExtension.Movie, xmlExtension.XPath, patch);
+                            break;
+
+                        case PrefabExtensionInsertAsSiblingPatch patch:
+                            WidgetComponent.RegisterPatch(xmlExtension.Movie, xmlExtension.XPath, patch);
+                            break;
+
                         case CustomPatch<XmlDocument> patch:
                             WidgetComponent.RegisterPatch(xmlExtension.Movie, patch.Apply);
                             break;