front-hub/src/utils/calcTariffPrices.ts

import { Tariff } from "@root/model/tariff";
import { mockDiscounts } from "../__mocks__/discounts";
import { PrivilegeWithAmount } from "@root/model/privilege";
import { AnyDiscount, PrivilegeDiscount, ServiceDiscount } from "../model/discount";


export function calcTariffPrices(tariff: Tariff, discounts: AnyDiscount[] = mockDiscounts): {
    price: number | undefined;
    priceWithDiscounts: number | undefined;
} {
    let price = tariff.price || tariff.privilegies.reduce((sum, privilege) => sum + privilege.amount * privilege.price, 0);

    const priceWithDiscounts = tariff.privilegies.reduce((sum, privilege) => {
        let privilegePrice = privilege.amount * privilege.price;

        const privilegeDiscount = findPrivilegeDiscount(privilege, discounts);
        if (privilegeDiscount) privilegePrice *= privilegeDiscount.target.products[0].factor;

        const serviceDiscount = findServiceDiscount(privilege.serviceKey, privilegePrice, discounts);
        if (serviceDiscount) privilegePrice *= serviceDiscount.target.factor;

        return sum + privilegePrice;
    }, 0);

    return {
        price,
        priceWithDiscounts,
    };
}

export function findPrivilegeDiscount(privilege: PrivilegeWithAmount, discounts: AnyDiscount[]): PrivilegeDiscount | null {
    const applicableDiscounts = discounts.filter((discount): discount is PrivilegeDiscount => {
        return (
            discount.conditionType === "privilege" &&
            privilege.privilegeId === discount.condition.privilege.id &&
            privilege.amount >= discount.condition.privilege.value
        );
    });

    if (!applicableDiscounts.length) return null;

    const maxValueDiscount = applicableDiscounts.reduce((prev, current) =>
        current.condition.privilege.value > prev.condition.privilege.value ? current : prev
    );

    return maxValueDiscount;
}

export function findServiceDiscount(
    serviceKey: string,
    currentPrice: number,
    discounts: AnyDiscount[],
): ServiceDiscount | null {
    const discountsForTariffService = discounts.filter((discount): discount is ServiceDiscount => {
        return (
            discount.conditionType === "service" &&
            discount.condition.service.id === serviceKey &&
            currentPrice >= discount.condition.service.value
        );
    });

    if (!discountsForTariffService.length) return null;

    const maxValueDiscount = discountsForTariffService.reduce((prev, current) => {
        return current.condition.service.value > prev.condition.service.value ? current : prev;
    });

    return maxValueDiscount;
}