From 2153c7b57d05419fb8b913daf31b40ff6956e37f Mon Sep 17 00:00:00 2001
From: Davide Di Pumpo <davidemak@gmail.com>
Date: Thu, 23 Oct 2025 19:28:39 +0200
Subject: [PATCH] Fixes nullable nested unions meta creation

---
 .changeset/rotten-oranges-ask.md              |  5 ++++
 .../components/OmegaForm/OmegaFormStuff.ts    | 29 +++++++++++++++----
 2 files changed, 28 insertions(+), 6 deletions(-)
 create mode 100644 .changeset/rotten-oranges-ask.md

diff --git a/.changeset/rotten-oranges-ask.md b/.changeset/rotten-oranges-ask.md
new file mode 100644
index 0000000000..5deaec7c2c
--- /dev/null
+++ b/.changeset/rotten-oranges-ask.md
@@ -0,0 +1,5 @@
+---
+"@effect-app/vue-components": patch
+---
+
+Fixes nullable nested unions meta creation
diff --git a/packages/vue-components/src/components/OmegaForm/OmegaFormStuff.ts b/packages/vue-components/src/components/OmegaForm/OmegaFormStuff.ts
index 8831cbbbac..1d4df881a9 100644
--- a/packages/vue-components/src/components/OmegaForm/OmegaFormStuff.ts
+++ b/packages/vue-components/src/components/OmegaForm/OmegaFormStuff.ts
@@ -304,6 +304,21 @@ const isNullableOrUndefined = (property: false | S.AST.AST | undefined) => {
   return false
 }
 
+// Helper function to recursively unwrap nested unions (e.g., S.NullOr(S.NullOr(X)) -> X)
+const unwrapNestedUnions = (types: readonly S.AST.AST[]): readonly S.AST.AST[] => {
+  const result: S.AST.AST[] = []
+  for (const type of types) {
+    if (S.AST.isUnion(type)) {
+      // Recursively unwrap nested unions
+      const unwrapped = unwrapNestedUnions(type.types)
+      result.push(...unwrapped)
+    } else {
+      result.push(type)
+    }
+  }
+  return result
+}
+
 export const createMeta = <T = any>(
   { meta = {}, parent = "", property, propertySignatures }: CreateMeta,
   acc: Partial<MetaRecord<T>> = {}
@@ -333,9 +348,9 @@ export const createMeta = <T = any>(
 
       const typeToProcess = p.type
       if (S.AST.isUnion(p.type)) {
-        const nonNullTypes = p
-          .type
-          .types
+        // First unwrap any nested unions, then filter out null/undefined
+        const unwrappedTypes = unwrapNestedUnions(p.type.types)
+        const nonNullTypes = unwrappedTypes
           .filter(
             (t) => t._tag !== "UndefinedKeyword" && t !== S.Null.ast
           )
@@ -548,7 +563,9 @@ export const createMeta = <T = any>(
     }
 
     if (S.AST.isUnion(property)) {
-      const nonNullType = property.types.find(
+      // First unwrap any nested unions, then filter out null/undefined
+      const unwrappedTypes = unwrapNestedUnions(property.types)
+      const nonNullType = unwrappedTypes.find(
         (t) => t._tag !== "UndefinedKeyword" && t !== S.Null.ast
       )!
 
@@ -560,11 +577,11 @@ export const createMeta = <T = any>(
         })
       }
 
-      if (property.types.every(S.AST.isLiteral)) {
+      if (unwrappedTypes.every(S.AST.isLiteral)) {
         return {
           ...meta,
           type: "select",
-          members: property.types.map((t) => t.literal)
+          members: unwrappedTypes.map((t) => t.literal)
         } as FieldMeta
       }