From f3ee820fa4ad453e7791241dce99c67e08eac33c Mon Sep 17 00:00:00 2001
From: shamoon <4887959+shamoon@users.noreply.github.com>
Date: Mon, 6 Apr 2026 21:59:11 -0700
Subject: [PATCH] Fix: prevent duplicate parent tag IDs (#12522)

---
 .../common/input/tags/tags.component.spec.ts       | 14 ++++++++++++++
 .../components/common/input/tags/tags.component.ts |  8 +++++---
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/src-ui/src/app/components/common/input/tags/tags.component.spec.ts b/src-ui/src/app/components/common/input/tags/tags.component.spec.ts
index ae543075e..21ca3eeff 100644
--- a/src-ui/src/app/components/common/input/tags/tags.component.spec.ts
+++ b/src-ui/src/app/components/common/input/tags/tags.component.spec.ts
@@ -205,6 +205,20 @@ describe('TagsComponent', () => {
     expect(component.value).toEqual([2, 1])
   })
 
+  it('should not duplicate parents when adding sibling nested tags', () => {
+    const root: Tag = { id: 1, name: 'root' }
+    const parent: Tag = { id: 2, name: 'parent', parent: 1 }
+    const leafA: Tag = { id: 3, name: 'leaf-a', parent: 2 }
+    const leafB: Tag = { id: 4, name: 'leaf-b', parent: 2 }
+    component.tags = [root, parent, leafA, leafB]
+
+    component.value = []
+    component.addTag(3)
+    component.addTag(4)
+
+    expect(component.value).toEqual([3, 2, 1, 4])
+  })
+
   it('should return ancestors from root to parent using getParentChain', () => {
     const root: Tag = { id: 1, name: 'root' }
     const mid: Tag = { id: 2, name: 'mid', parent: 1 }
diff --git a/src-ui/src/app/components/common/input/tags/tags.component.ts b/src-ui/src/app/components/common/input/tags/tags.component.ts
index 4546dabcb..c540ff9d7 100644
--- a/src-ui/src/app/components/common/input/tags/tags.component.ts
+++ b/src-ui/src/app/components/common/input/tags/tags.component.ts
@@ -153,11 +153,13 @@ export class TagsComponent implements OnInit, ControlValueAccessor {
   }
 
   public onAdd(tag: Tag) {
-    if (tag.parent) {
+    if (tag?.parent) {
       // add all parents recursively
       const parent = this.getTag(tag.parent)
-      this.value = [...this.value, parent.id]
-      this.onAdd(parent)
+      if (parent && !this.value.includes(parent.id)) {
+        this.value = [...this.value, parent.id]
+        this.onAdd(parent)
+      }
     }
   }