Function normalizeUnionType

client/src/utils/schemaUtils.ts:237–303

(schema: JsonSchemaType)

 * @returns A normalized schema or the original schema
 */
export function normalizeUnionType(schema: JsonSchemaType): JsonSchemaType {
  // Handle anyOf with exactly 2 items (type and null) - unified handling
  // Preserves enum and other properties automatically
  if (
    schema.anyOf &&
    schema.anyOf.length === 2 &&
    schema.anyOf.some((t) => (t as JsonSchemaType).type === "null")
  ) {
    const nonNullItem = schema.anyOf.find((t) => {
      const item = t as JsonSchemaType;
      return item?.type !== "null";
    }) as JsonSchemaType;

    // Only process if non-null item has type or enum
    if (nonNullItem?.type || nonNullItem?.enum) {
      return {
        ...schema,
        ...nonNullItem,
        type: nonNullItem?.type || (nonNullItem?.enum ? "string" : undefined),
        nullable: true,
        anyOf: undefined,
      };
    }
  }

  // Handle array type with exactly string and null
  if (
    Array.isArray(schema.type) &&
    schema.type.length === 2 &&
    schema.type.includes("string") &&
    schema.type.includes("null")
  ) {
    return { ...schema, type: "string", nullable: true };
  }

  // Handle array type with exactly boolean and null
  if (
    Array.isArray(schema.type) &&
    schema.type.length === 2 &&
    schema.type.includes("boolean") &&
    schema.type.includes("null")
  ) {
    return { ...schema, type: "boolean", nullable: true };
  }

  // Handle array type with exactly number and null
  if (
    Array.isArray(schema.type) &&
    schema.type.length === 2 &&
    schema.type.includes("number") &&
    schema.type.includes("null")
  ) {
    return { ...schema, type: "number", nullable: true };
  }

  // Handle array type with exactly integer and null
  if (
    Array.isArray(schema.type) &&