#360

frontend/src/pages/theatres/TheatreDetailPage.tsx

@@ -102,10 +102,33 @@ const compareTagName = (a: Tag, b: Tag): number =>
     a.name === b.name ? 0 : (a.name < b.name ? -1 : 1)
 
 
-const tagsByCategory = (tags: Tag[]): Partial<Record<Category, Tag[]>> => {
-  const grouped: Partial<Record<Category, Tag[]>> = { }
+const flattenTags = (tags: Tag[]): Tag[] => {
+  const flattened: Tag[] = []
+  const seen = new Set<number> ()
+
+  const visit = (tag: Tag) => {
+    if (seen.has (tag.id))
+      return
+
+    seen.add (tag.id)
+    flattened.push (tag)
+
+    for (const child of tag.children ?? [])
+      visit (child)
+  }
 
   for (const tag of tags)
+    visit (tag)
+
+  return flattened
+}
+
+
+const tagsByCategory = (tags: Tag[]): Partial<Record<Category, Tag[]>> => {
+  const flattenedTags = flattenTags (tags)
+  const grouped: Partial<Record<Category, Tag[]>> = { }
+
+  for (const tag of flattenedTags)
     {
       grouped[tag.category] ??= []
       grouped[tag.category]!.push (tag)