From b98bf041ae9e215df67f4fbe288f2f53fa1bbfd8 Mon Sep 17 00:00:00 2001
From: Attila Cseh <attila.cseh@outlook.hu>
Date: Mon, 25 Aug 2025 12:33:32 +0200
Subject: [PATCH 1/2] node field dnd logic updatedto prevent duplicates

---
 .../components/sidePanel/builder/dnd-hooks.ts | 38 +++++++++++++++++--
 1 file changed, 35 insertions(+), 3 deletions(-)

diff --git a/invokeai/frontend/web/src/features/nodes/components/sidePanel/builder/dnd-hooks.ts b/invokeai/frontend/web/src/features/nodes/components/sidePanel/builder/dnd-hooks.ts
index c9156c6782c..e6b12446cef 100644
--- a/invokeai/frontend/web/src/features/nodes/components/sidePanel/builder/dnd-hooks.ts
+++ b/invokeai/frontend/web/src/features/nodes/components/sidePanel/builder/dnd-hooks.ts
@@ -34,7 +34,7 @@ import {
 import { selectFormRootElementId, selectNodesSlice, selectWorkflowForm } from 'features/nodes/store/selectors';
 import type { FieldInputTemplate, StatefulFieldValue } from 'features/nodes/types/field';
 import type { ElementId, FormElement } from 'features/nodes/types/workflow';
-import { buildNodeFieldElement, isContainerElement } from 'features/nodes/types/workflow';
+import { buildNodeFieldElement, isContainerElement, isNodeFieldElement } from 'features/nodes/types/workflow';
 import type { RefObject } from 'react';
 import { useCallback, useEffect, useMemo, useState } from 'react';
 import { flushSync } from 'react-dom';
@@ -121,6 +121,29 @@ const useElementExists = () => {
   return _elementExists;
 };
 
+/**
+ * Checks if a node field element exists in the form.
+ *
+ * @param form The form to check
+ * @param nodeId The id of the node
+ * @param fieldName The name of field
+ *
+ * @returns True if the element exists, false otherwise
+ */
+export const useNodeFieldElementExists = () => {
+  const store = useAppStore();
+  const nodeFieldElementExists = useCallback(
+    (nodeId: string, fieldName: string): boolean => {
+      const form = selectWorkflowForm(store.getState());
+      return Object.values(form.elements)
+        .filter(isNodeFieldElement)
+        .some((el) => el.data.fieldIdentifier.nodeId === nodeId && el.data.fieldIdentifier.fieldName === fieldName);
+    },
+    [store]
+  );
+  return nodeFieldElementExists;
+};
+
 /**
  * Wrapper around `getAllowedDropRegions` that provides the form state from the store.
  * @see {@link getAllowedDropRegions}
@@ -368,6 +391,7 @@ export const useFormElementDnd = (
   const [activeDropRegion, setActiveDropRegion] = useState<CenterOrEdge | null>(null);
   const getElement = useGetElement();
   const getAllowedDropRegions = useGetAllowedDropRegions();
+  const nodeFieldElementExists = useNodeFieldElementExists();
 
   useEffect(() => {
     if (isRootElement) {
@@ -401,7 +425,7 @@ export const useFormElementDnd = (
         // TODO(psyche): This causes a kinda jittery behaviour - need a better heuristic to determine stickiness
         getIsSticky: () => false,
         canDrop: ({ source }) => {
-          if (isNodeFieldDndData(source.data)) {
+          if (isNodeFieldDndData(source.data) && !nodeFieldElementExists(source.data.nodeId, source.data.fieldName)) {
             return true;
           }
           if (isFormElementDndData(source.data)) {
@@ -449,7 +473,15 @@ export const useFormElementDnd = (
         },
       })
     );
-  }, [dragHandleRef, draggableRef, elementId, getAllowedDropRegions, getElement, isRootElement]);
+  }, [
+    dragHandleRef,
+    draggableRef,
+    elementId,
+    getAllowedDropRegions,
+    getElement,
+    nodeFieldElementExists,
+    isRootElement,
+  ]);
 
   return [activeDropRegion, isDragging] as const;
 };

From 310057b7759d1f5a3494018483e9387e9bb5f531 Mon Sep 17 00:00:00 2001
From: Attila Cseh <attila.cseh@outlook.hu>
Date: Mon, 25 Aug 2025 12:52:16 +0200
Subject: [PATCH 2/2] useNodeFieldElementExists turned private

---
 .../features/nodes/components/sidePanel/builder/dnd-hooks.ts    | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/invokeai/frontend/web/src/features/nodes/components/sidePanel/builder/dnd-hooks.ts b/invokeai/frontend/web/src/features/nodes/components/sidePanel/builder/dnd-hooks.ts
index e6b12446cef..788a613a7a5 100644
--- a/invokeai/frontend/web/src/features/nodes/components/sidePanel/builder/dnd-hooks.ts
+++ b/invokeai/frontend/web/src/features/nodes/components/sidePanel/builder/dnd-hooks.ts
@@ -130,7 +130,7 @@ const useElementExists = () => {
  *
  * @returns True if the element exists, false otherwise
  */
-export const useNodeFieldElementExists = () => {
+const useNodeFieldElementExists = () => {
   const store = useAppStore();
   const nodeFieldElementExists = useCallback(
     (nodeId: string, fieldName: string): boolean => {