import { computed, ref, watch } from 'vue';
import { fetchMyBusinesses } from '@/api/businesses';
import { useAuthStore } from '@/stores/auth';

const ownedBusinessIds = ref<Set<string>>(new Set());
const loaded = ref(false);
let loadPromise: Promise<void> | null = null;
let authWatchStarted = false;

export function useOwnedBusiness() {
  const auth = useAuthStore();

  async function ensureLoaded(force = false) {
    if (auth.token && !auth.user) {
      await auth.loadUser();
    }

    if (!auth.isLoggedIn || !auth.isBusinessOwner) {
      ownedBusinessIds.value = new Set();
      loaded.value = true;
      loadPromise = null;
      return;
    }

    if (loaded.value && !force) return;
    if (loadPromise) {
      await loadPromise;
      return;
    }

    loadPromise = (async () => {
      try {
        const businesses = await fetchMyBusinesses();
        ownedBusinessIds.value = new Set(businesses.map((item) => item.id));
      } catch {
        ownedBusinessIds.value = new Set();
      } finally {
        loaded.value = true;
        loadPromise = null;
      }
    })();

    await loadPromise;
  }

  if (!authWatchStarted) {
    authWatchStarted = true;
    watch(
      () => [auth.token, auth.user?.id, auth.user?.role] as const,
      () => {
        loaded.value = false;
        loadPromise = null;
        void ensureLoaded(true);
      },
    );
  }

  function isOwnBusiness(businessId: string | null | undefined): boolean {
    if (!businessId || !auth.isBusinessOwner) return false;
    return ownedBusinessIds.value.has(businessId);
  }

  const ownsAnyBusiness = computed(() => ownedBusinessIds.value.size > 0);

  return {
    loaded,
    ownsAnyBusiness,
    ensureLoaded,
    isOwnBusiness,
  };
}