fix: canvas loop bug and node placement

src/components/FlowEditor/editor/Automation2FlowEditor.tsx

@@ -158,6 +158,7 @@ export const Automation2FlowEditor: React.FC<Automation2FlowEditorProps> = ({ in
   const [versions, setVersions] = useState<AutoVersion[]>([]);
   const [currentVersionId, setCurrentVersionId] = useState<string | null>(null);
   const [versionLoading, setVersionLoading] = useState(false);
+  const didBootstrapEmptyCanvasRef = useRef(false);
 
   const [targetFeatureInstanceId, setTargetFeatureInstanceId] = useState<string | null>(instanceId);
 
@@ -598,8 +599,22 @@ export const Automation2FlowEditor: React.FC<Automation2FlowEditorProps> = ({ in
 
   useEffect(() => {
     if (loading || nodeTypes.length === 0) return;
-    if (currentWorkflowId || initialWorkflowId) return;
+    if (currentWorkflowId || initialWorkflowId) {
-    if (canvasNodes.length > 0) return;
+      didBootstrapEmptyCanvasRef.current = false;
+      return;
+    }
+    if (didBootstrapEmptyCanvasRef.current) return;
+    didBootstrapEmptyCanvasRef.current = true;
+    if (canvasNodes.length === 0 && canvasConnections.length === 0 && invocations.length === 0) {
+      return;
+    }
+    console.debug(`${LOG} bootstrapping empty canvas`, {
+      currentWorkflowId,
+      initialWorkflowId,
+      canvasNodes: canvasNodes.length,
+      canvasConnections: canvasConnections.length,
+      invocations: invocations.length,
+    });
     applyGraphWithSync({ nodes: [], connections: [] }, [], {
       skipHistory: true,
     });
@@ -609,8 +624,9 @@ export const Automation2FlowEditor: React.FC<Automation2FlowEditorProps> = ({ in
     currentWorkflowId,
     initialWorkflowId,
     canvasNodes.length,
+    canvasConnections.length,
+    invocations.length,
     applyGraphWithSync,
-    t,
   ]);
 
   const toggleCategory = useCallback((id: string) => {

src/components/FlowEditor/editor/FlowCanvas.tsx

@@ -20,6 +20,8 @@ import { useLanguage } from '../../../providers/language/LanguageContext';
 import { AiBadge } from '../nodes/shared/AiBadge';
 import { switchOutputLabel } from '../nodes/shared/graphUtils';
 
+const LOG = '[FlowCanvas]';
+
 export interface CanvasNode {
   id: string;
   type: string;
@@ -842,6 +844,8 @@ export const FlowCanvas = forwardRef<FlowCanvasHandle, FlowCanvasProps>(function
 
   const onHistoryCheckpointRef = useRef(onHistoryCheckpoint);
   onHistoryCheckpointRef.current = onHistoryCheckpoint;
+  const onSelectionChangeRef = useRef(onSelectionChange);
+  onSelectionChangeRef.current = onSelectionChange;
 
   const emitHistoryCheckpoint = useCallback(() => {
     onHistoryCheckpointRef.current?.();
@@ -1019,12 +1023,19 @@ export const FlowCanvas = forwardRef<FlowCanvasHandle, FlowCanvasProps>(function
     ]
   );
 
+  const lastEmittedSelectionRef = useRef<{ nodeId: string | null; signature: string | null }>({
+    nodeId: null,
+    signature: null,
+  });
+
   useEffect(() => {
-    if (onSelectionChange) {
     const node = selectedNodeId ? nodes.find((n) => n.id === selectedNodeId) ?? null : null;
-      onSelectionChange(node);
+    const signature = node ? JSON.stringify(node) : null;
-    }
+    const last = lastEmittedSelectionRef.current;
-  }, [selectedNodeId, nodes, onSelectionChange]);
+    if (last.nodeId === selectedNodeId && last.signature === signature) return;
+    lastEmittedSelectionRef.current = { nodeId: selectedNodeId, signature };
+    onSelectionChangeRef.current?.(node);
+  }, [selectedNodeId, nodes]);
 
   const handleConnectionClick = useCallback((e: React.MouseEvent, connId: string) => {
     e.stopPropagation();
@@ -1088,6 +1099,11 @@ export const FlowCanvas = forwardRef<FlowCanvasHandle, FlowCanvasProps>(function
   const handleDrop = useCallback(
     async (e: React.DragEvent) => {
       e.preventDefault();
+      console.debug(`${LOG} drop received`, {
+        types: Array.from(e.dataTransfer.types),
+        clientX: e.clientX,
+        clientY: e.clientY,
+      });
       // 1) externe Drop-Targets (z. B. ``application/json+workflow`` aus UDB-FilesTab)
       if (onExternalDrop) {
         const reservedMimes = new Set([
@@ -1113,16 +1129,35 @@ export const FlowCanvas = forwardRef<FlowCanvasHandle, FlowCanvasProps>(function
       }
       // 2) Standard: Node-Type aus der NodeSidebar
       const raw = e.dataTransfer.getData('application/json');
-      if (!raw || !containerRef.current) return;
+      if (!raw || !containerRef.current) {
+        console.debug(`${LOG} drop ignored`, {
+          hasRaw: Boolean(raw),
+          hasContainer: Boolean(containerRef.current),
+        });
+        return;
+      }
       try {
         const { type } = JSON.parse(raw);
         const el = containerRef.current;
         const rect = el.getBoundingClientRect();
         const x = (e.clientX - rect.left - panOffset.x) / zoom - NODE_WIDTH / 2;
         const y = (e.clientY - rect.top - panOffset.y) / zoom - NODE_HEIGHT / 2;
+        console.debug(`${LOG} placing node from drop`, {
+          type,
+          raw,
+          dropX: x,
+          dropY: y,
+          panOffset,
+          zoom,
+        });
         onDropNodeType(type, Math.max(0, x), Math.max(0, y));
         emitHistoryCheckpoint();
-      } catch (_) {}
+      } catch (error) {
+        console.debug(`${LOG} drop parse failed`, {
+          raw,
+          error,
+        });
+      }
     },
     [onDropNodeType, onExternalDrop, panOffset, zoom, emitHistoryCheckpoint]
   );