export type SupportedCurrency = 'CHF' | 'DKK' | 'EUR';
export declare const SUPPORTED_CURRENCIES: SupportedCurrency[];
export declare const BASE_CURRENCY: SupportedCurrency;
/**
 * CHF-based exchange rates. `rates[currency]` is "how many units of
 * `currency` equal 1 CHF" — so `rates.CHF` is always `1`.
 */
export interface CurrencyRates {
    base: 'CHF';
    rates: Record<SupportedCurrency, number>;
    fetchedAt: number;
}
/**
 * Live CHF-based exchange rates for DKK/EUR, sourced from the Frankfurter API
 * (ECB reference rates — the same market rates Google Finance quotes). Used
 * to convert the CHF-denominated pricing model into a user's preferred
 * display currency; billing itself always stays in CHF.
 */
export declare class CueCurrency {
    private _cached;
    private _pending;
    /**
     * Fetches the current rates, cached in-memory for one hour. Concurrent
     * calls share a single in-flight request. If a refetch fails and a
     * previous rate set is cached, the stale rates are served instead of
     * throwing — a transient network blip shouldn't break the pricing UI.
     */
    getRates(forceRefresh?: boolean): Promise<CurrencyRates>;
    private _fetchRates;
    /** Converts an amount in CHF into `currency` using `rates`. */
    fromBase(amountChf: number, currency: SupportedCurrency, rates: CurrencyRates): number;
    /** Converts an amount in `currency` back into CHF using `rates`. */
    toBase(amount: number, currency: SupportedCurrency, rates: CurrencyRates): number;
}