turash/bugulma/frontend/hooks/useAvailableCategories.ts

import type { BackendHeritageDataResponse } from '@/schemas/backend/heritage';
import { useMemo } from 'react';

export const useAvailableCategories = (heritageData: BackendHeritageDataResponse | undefined) => {
  return useMemo(() => {
    if (!heritageData?.timeline_items) return [];
    const categories = new Set(
      heritageData.timeline_items.map((item) => item.category).filter((cat) => cat !== undefined)
    );
    return Array.from(categories).sort();
  }, [heritageData]);
};