import type { Price } from '../money/price.js';
/**
 * Builds a rounded {@link Price} from a unit price and quantity.
 *
 * The unit price is multiplied by the quantity using decimal arithmetic to avoid
 * floating-point rounding errors, then rounded down to the currency's scale.
 *
 * @param unitPrice - The price per unit (e.g. per kWh, per minute, or a flat fee). Returns undefined when null.
 * @param currency - The ISO currency code used for arithmetic and rounding.
 * @param taxRate - Optional tax rate as a percentage; when set, populates `incl_vat`.
 * @param quantity - The number of units to multiply by. Defaults to 1.
 * @returns The rounded price, or undefined when `unitPrice` is null.
 */
export declare function buildPrice(unitPrice: number | undefined, currency: string, taxRate?: number | null, quantity?: number): Price | undefined;
/**
 * Sums a set of already-rounded Prices into one Price, so the
 * resulting total always reconciles against the sum of its own components.
 */
export declare function sumPrices(currency: string, prices: (Price | undefined)[]): Price;
export declare function baseCalculateFixedCost(flatFee: number | null | undefined, currency: string, taxRate?: number | null): Price | undefined;
export declare function baseCalculateEnergyCost(totalKwh: number, feePerKwh: number | null | undefined, currency: string, taxRate?: number | null): Price | undefined;
export declare function baseCalculateTimeCost(totalMinutes: number, feePerMinute: number | null | undefined, currency: string, taxRate?: number | null): Price | undefined;
export declare function baseCalculateTotalCost(totalKwh: number, totalMinutes: number, tariffPerSession: number | null | undefined, tariffPerKwh: number | null | undefined, tariffPerMinute: number | null | undefined, currency: string, taxRate?: number | null): Price;