Tighten editor scene mutation boundary

editor/app/Services/Engine/EngineEditorServices.cpp

@@ -177,7 +177,7 @@ GameObject* FindGameObjectByItemId(
     SceneManager& sceneManager,
     std::string_view itemId) {
     Scene* scene = ResolvePrimaryScene(sceneManager);
-    const std::optional<GameObject::ID> gameObjectId =
+    const std::optional<EditorSceneObjectId> gameObjectId =
         ParseEditorGameObjectItemId(itemId);
     if (scene == nullptr || !gameObjectId.has_value()) {
         return nullptr;
@@ -186,6 +186,27 @@ GameObject* FindGameObjectByItemId(
     return scene->FindByID(gameObjectId.value());
 }
 
+EditorSceneHierarchyNode BuildHierarchySnapshotNodeRecursive(
+    const GameObject& gameObject) {
+    EditorSceneHierarchyNode node = {};
+    node.itemId = MakeEditorGameObjectItemId(gameObject.GetID());
+    node.displayName = gameObject.GetName().empty()
+        ? std::string("GameObject")
+        : gameObject.GetName();
+    node.children.reserve(gameObject.GetChildCount());
+    for (std::size_t childIndex = 0u;
+         childIndex < gameObject.GetChildCount();
+         ++childIndex) {
+        const GameObject* child = gameObject.GetChild(childIndex);
+        if (child == nullptr) {
+            continue;
+        }
+
+        node.children.push_back(BuildHierarchySnapshotNodeRecursive(*child));
+    }
+    return node;
+}
+
 bool MoveGameObjectRelativeToTarget(
     SceneManager& sceneManager,
     std::string_view itemId,
@@ -313,6 +334,25 @@ public:
         return ResolvePrimaryScene(m_sceneManager);
     }
 
+    EditorSceneHierarchySnapshot BuildHierarchySnapshot() const override {
+        EditorSceneHierarchySnapshot snapshot = {};
+        Scene* scene = ResolvePrimaryScene(m_sceneManager);
+        if (scene == nullptr) {
+            return snapshot;
+        }
+
+        const std::vector<GameObject*> roots = scene->GetRootGameObjects();
+        snapshot.roots.reserve(roots.size());
+        for (const GameObject* root : roots) {
+            if (root == nullptr) {
+                continue;
+            }
+
+            snapshot.roots.push_back(BuildHierarchySnapshotNodeRecursive(*root));
+        }
+        return snapshot;
+    }
+
     bool OpenSceneAsset(const std::filesystem::path& scenePath) override {
         if (scenePath.empty()) {
             return false;
@@ -344,6 +384,25 @@ public:
         return FindGameObjectByItemId(m_sceneManager, itemId);
     }
 
+    bool AddComponent(
+        std::string_view itemId,
+        std::string_view componentTypeName) override {
+        if (componentTypeName.empty()) {
+            return false;
+        }
+
+        GameObject* gameObject = FindGameObject(itemId);
+        if (gameObject == nullptr) {
+            return false;
+        }
+
+        Component* addedComponent =
+            ComponentFactoryRegistry::Get().CreateComponent(
+                gameObject,
+                std::string(componentTypeName));
+        return addedComponent != nullptr;
+    }
+
     bool RenameGameObject(
         std::string_view itemId,
         std::string_view newName) override {