import { Formatters } from "./interpolation.js";
import { Locale } from "./locale.js";
export declare class U27N {
    #private;
    readonly clients: Set<U27N.Client>;
    readonly formatters: Formatters;
    readonly updateHandlers: Set<U27N.UpdateHandler>;
    constructor(options: U27N.Options);
    get locale(): Locale | null;
    setLocale(code: string): Promise<void>;
    registerSetLocaleHook(hook: U27N.SetLocaleHook): U27N.SetLocaleHook;
    unregisterSetLocaleHook(hook: U27N.SetLocaleHook): void;
    setLocaleAuto(locales: string[]): Promise<void>;
    ensureLocale(code: string): Locale;
    getLocale(code: string): Locale | undefined;
    update(): void;
    static detectLocale(locales: string[]): string | undefined;
}
export declare namespace U27N {
    interface Client {
        fetchResources(controller: U27N, locale: Locale): Promise<void>;
    }
    interface LocaleFactory {
        (controller: U27N, code: string): Locale;
    }
    interface Options {
        clients?: Client[];
        localeFactory: LocaleFactory;
        formatters?: Formatters;
    }
    interface UpdateHandler {
        (controller: U27N): void;
    }
    interface SetLocaleHook {
        (targetLocale: Locale): void;
    }
}