Interface Shop

interface Shop {
    addItem(
        item: {
            category?: string;
            consumable?: boolean;
            description?: string;
            id: string;
            maxPerUser?: number;
            name: string;
            price: number;
            stock?: number;
            [meta: string]: unknown;
        },
    ): ShopItem;
    buy(user: string, itemId: string, qty?: number): ShopPurchase;
    clear(): void;
    getCatalog(): ShopItem[];
    getInventory(user: string): { id: string; name: string; qty: number }[];
    getInventoryValue(user: string): number;
    getItem(id: string): ShopItem | null;
    giveItem(from: string, to: string, itemId: string, qty?: number): void;
    hasItem(user: string, itemId: string, qty?: number): boolean;
    load(snapshot: Record<string, unknown>): void;
    onBuy(cb: (purchase: ShopPurchase) => void): () => void;
    onUse(
        cb: (info: { item: ShopItem; remaining: number; user: string }) => void,
    ): () => void;
    removeItem(id: string): boolean;
    renderCatalog(options?: { category?: string; title?: string }): string;
    restock(id: string, qty?: number): number;
    sellBack(
        user: string,
        itemId: string,
        qty?: number,
    ): { balance: number; refund: number };
    toJSON(): Record<string, unknown>;
    updateItem(
        id: string,
        patch: Partial<
            Pick<
                ShopItem,
                | "name"
                | "price"
                | "description"
                | "stock"
                | "consumable"
                | "maxPerUser"
                | "category",
            >,
        >,
    ): ShopItem;
    useItem(user: string, itemId: string): number;
}