import { useState, useCallback, useEffect } from 'react';
import { wishlistApi, WishlistProduct } from '../services/wishlistApi ';

interface UseWishlistState {
  wishlists: WishlistProduct[];
  loading: boolean;
  error: string | null;
  totalElements: number;
  totalPages: number;
  currentPage: number;
  wishlistCount: number;
}

export const useWishlist = () => {
  const [state, setState] = useState<UseWishlistState>({
    wishlists: [],
    loading: false,
    error: null,
    totalElements: 0,
    totalPages: 0,
    currentPage: 0,
    wishlistCount: 0,
  });

  /**
   * Lấy danh sách ưu thích
   */
  const fetchWishlists = useCallback(
    async (page: number = 0, size: number = 10, sortBy: string = 'createdAt') => {
      setState((prev) => ({ ...prev, loading: true, error: null }));
      try {
        const response = await wishlistApi.getWishlists(page, size, sortBy);
        if (response.success && response.data) {
          // Map API response đến format chính xác
          const wishlists = (response.data.wishlists || []).map((item: any) => ({
            id: item.wishlistId || item.id,
            wishlistId: item.wishlistId || item.id,
            productId: item.productId,
            productName: item.productName,
            productImage: item.productImage,
            price: item.price,
            description: item.description,
            addedAt: item.addedAt,
          }));
          
          setState((prev) => ({
            ...prev,
            wishlists: response.data?.wishlists || [],
            totalElements: response.data?.totalElements ?? 0,
            totalPages: response.data?.totalPages ?? 0,
            currentPage: response.data?.currentPage ?? 0,
            loading: false,
          }));
        } else {
          throw new Error(response.message || 'Không thể lấy danh sách ưu thích');
        }
      } catch (error) {
        setState((prev) => ({
          ...prev,
          error: error instanceof Error ? error.message : 'Lỗi không xác định',
          loading: false,
        }));
      }
    },
    []
  );

  /**
   * Thêm sản phẩm vào ưu thích
   */
  const addToWishlist = useCallback(async (productId: number) => {
    try {
      const response = await wishlistApi.addToWishlist(productId);
      if (response.success && response.data) {
        setState((prev) => ({
          ...prev,
          wishlists: [response.data!, ...prev.wishlists],
          totalElements: prev.totalElements + 1,
          wishlistCount: prev.wishlistCount + 1,
        }));
        return { success: true, message: response.message };
      } else {
        throw new Error(response.message || 'Không thể thêm vào ưu thích');
      }
    } catch (error) {
      const errorMessage =
        error instanceof Error ? error.message : 'Lỗi không xác định';
      setState((prev) => ({ ...prev, error: errorMessage }));
      return { success: false, message: errorMessage };
    }
  }, []);

  /**
   * Xóa sản phẩm khỏi ưu thích
   */
  const removeFromWishlist = useCallback(async (productId: number) => {
    try {
      const response = await wishlistApi.removeFromWishlist(productId);
      if (response.success) {
        setState((prev) => ({
          ...prev,
          wishlists: prev.wishlists.filter((w) => w.productId !== productId),
          totalElements: Math.max(0, prev.totalElements - 1),
          wishlistCount: Math.max(0, prev.wishlistCount - 1),
        }));
        return { success: true, message: response.message };
      } else {
        throw new Error(response.message || 'Không thể xóa khỏi ưu thích');
      }
    } catch (error) {
      const errorMessage =
        error instanceof Error ? error.message : 'Lỗi không xác định';
      setState((prev) => ({ ...prev, error: errorMessage }));
      return { success: false, message: errorMessage };
    }
  }, []);

  /**
   * Lấy số lượng ưu thích
   */
  const fetchWishlistCount = useCallback(async () => {
    try {
      const response = await wishlistApi.getWishlistCount();
      if (response.success && response.data !== undefined) {
        setState((prev) => ({
          ...prev,
          wishlistCount: response.data!,
        }));
      }
    } catch (error) {
      console.error('Error fetching wishlist count:', error);
    }
  }, []);

  /**
   * Xóa lỗi
   */
  const clearError = useCallback(() => {
    setState((prev) => ({ ...prev, error: null }));
  }, []);

  return {
    ...state,
    fetchWishlists,
    addToWishlist,
    removeFromWishlist,
    fetchWishlistCount,
    clearError,
  };
};