import { CartData, Discount, PrivilegeCartData, Tariff, applyCartDiscount, applyLoyaltyDiscount, applyPrivilegeDiscounts, applyServiceDiscounts } from "@frontend/kitui";


export function calcCart(
    tariffs: Tariff[],
    discounts: Discount[],
    purchasesAmount: number,
    coupon?: string,
): CartData {
    const cartData: CartData = {
        services: [],
        priceBeforeDiscounts: 0,
        priceAfterDiscounts: 0,
        itemCount: 0,
        appliedCartPurchasesDiscount: null,
        appliedLoyaltyDiscount: null,
        allAppliedDiscounts: [],
    };

    const serviceTariffType: Record<string, number> = {};

    tariffs.forEach(tariff => {
        if (tariff.price && tariff.price > 0) cartData.priceBeforeDiscounts += tariff.price;

        tariff.privilegies.forEach(privilege => {
            serviceTariffType[privilege.serviceKey] ??= +tariff.isCustom;
            const isIncompatibleTariffs = serviceTariffType[privilege.serviceKey] ^ +tariff.isCustom
            if (isIncompatibleTariffs) throw new Error("Если взят готовый тариф, то кастомный на этот сервис сделать уже нельзя");

            let serviceData = cartData.services.find(service => service.serviceKey === privilege.serviceKey);
            if (!serviceData) {
                serviceData = {
                    serviceKey: privilege.serviceKey,
                    privileges: [],
                    price: 0,
                    appliedServiceDiscount: null,
                };
                cartData.services.push(serviceData);
            }

            const privilegePrice = privilege.amount * privilege.price;

            if (!tariff.price) cartData.priceBeforeDiscounts += privilegePrice;

            const privilegeData: PrivilegeCartData = {
                tariffId: tariff._id,
                serviceKey: privilege.serviceKey,
                privilegeId: privilege.privilegeId,
                description: privilege.description,
                price: privilegePrice,
                appliedPrivilegeDiscount: null,
                tariffName: tariff.name,
            };

            serviceData.privileges.push(privilegeData);
            serviceData.price += privilegePrice;
            cartData.priceAfterDiscounts += privilegePrice;
            cartData.itemCount++;
        });
    });

    applyPrivilegeDiscounts(cartData, discounts);
    applyServiceDiscounts(cartData, discounts);
    applyCartDiscount(cartData, discounts);
    applyLoyaltyDiscount(cartData, discounts, purchasesAmount);

    cartData.allAppliedDiscounts = Array.from(new Set(cartData.allAppliedDiscounts));

    return cartData;
}

export function findDiscountFactor(discount: Discount | null | undefined): number {
    if (!discount) return 1;

    if (discount.Condition.CartPurchasesAmount > 0) return Number(discount.Target.Factor);

    if (discount.Condition.PurchasesAmount > 0) return Number(discount.Target.Factor);

    if (discount.Condition.Product !== "") {
        const product = discount.Target.Products[0];
        if (!product) throw new Error("Discount target product not found");
        return Number(product.Factor);
    }

    if ((discount.Condition.Group as string) !== "") return Number(discount.Target.Factor);
    if (discount.Condition.UserType) return Number(discount.Target.Factor);
    if (discount.Condition.User !== "") {
        const product = discount.Target.Products[0];
        if (!product) throw new Error("Discount target product not found");

        return Number(product.Factor);
    }

    return 1;
}

export function formatDiscountFactor(factor: number): string {
    return `${((1 - factor) * 100).toFixed(1)}%`;
}