import { create } from "zustand";
import { persist, createJSONStorage } from "zustand/middleware";

export interface CartItem {
  product_id: number;
  product_name: string;
  price: number;
  quantity: number;
  image_url?: string;
}

interface CartState {
  items: CartItem[];
  tableNumber: number;
  tableToken: string | null;
  addItem: (item: Omit<CartItem, "quantity">) => void;
  removeItem: (productId: number) => void;
  updateQuantity: (productId: number, quantity: number) => void;
  clearCart: () => void;
  setTableNumber: (num: number) => void;
  setTableToken: (token: string) => void;
  getTotalPrice: () => number;
  getTotalItems: () => number;
}

export const useCartStore = create<CartState>()(
  persist(
    (set, get) => ({
      items: [],
      tableNumber: 1,
      tableToken: null,

      addItem: (item) => {
        const items = get().items;
        const existing = items.find((i) => i.product_id === item.product_id);

        if (existing) {
          set({
            items: items.map((i) =>
              i.product_id === item.product_id
                ? { ...i, quantity: i.quantity + 1 }
                : i
            ),
          });
        } else {
          set({ items: [...items, { ...item, quantity: 1 }] });
        }
      },

      removeItem: (productId) => {
        set({ items: get().items.filter((i) => i.product_id !== productId) });
      },

      updateQuantity: (productId, quantity) => {
        if (quantity <= 0) {
          get().removeItem(productId);
          return;
        }
        set({
          items: get().items.map((i) =>
            i.product_id === productId ? { ...i, quantity } : i
          ),
        });
      },

      clearCart: () => set({ items: [] }),

      setTableNumber: (num) => set({ tableNumber: num }),
      setTableToken: (token) => set({ tableToken: token }),

      getTotalPrice: () =>
        get().items.reduce((sum, i) => sum + Number(i.price) * i.quantity, 0),

      getTotalItems: () =>
        get().items.reduce((sum, i) => sum + i.quantity, 0),
    }),
    { 
      name: "garson-cart",
      storage: createJSONStorage(() => typeof window !== "undefined" ? sessionStorage : localStorage)
    }
  )
);