import { Logger, LoggerService } from '@acoustic-content-sdk/api';
import { Observable, UnaryFunction } from 'rxjs';
export declare const ROOT_ID: string;
export interface NavigationJson {
    id: string;
    children?: NavigationJson[];
}
interface Navigation {
    children: Record<string, string[]>;
    parents: Record<string, string>;
}
export declare function isNotRoot(aId: string): boolean;
/**
 * Builds a navigation structure from the navigation element
 *
 * @param aJson - the navigation element
 *
 * @returns the navigation structure
 */
export declare function navigationFromJson(aJson: NavigationJson, aLogger: Logger): Navigation;
/**
 * Interface that exposes selectors to the navigation structure
 */
export interface NavSelectors {
    /**
     * ID of the (virtual) root item of the navigation
     */
    root: string;
    /**
     * Selects the children of a particular item
     */
    selectChildren: UnaryFunction<string, Observable<string[]>>;
    /**
     * Selects the parent of a particular item
     */
    selectParent: UnaryFunction<string, Observable<string>>;
}
/**
 * Returns selectors that access parent and child nodes from a navigation structure
 *
 * @param aJson$ - the JSON that represents the navigation
 * @param aLogSvc - optional logger service
 * @returns the selectors
 */
export declare function getNavSelectors(aJson$: Observable<NavigationJson>, aLogSvc?: LoggerService): NavSelectors;
/**
 * Constructs a breadcrumb trail starting at a particular ID
 *
 * @param aId  - the start ID
 * @param aSelParent - selector function for the parent node
 * @param aSelId - selector function for the ID from a parent node
 *
 * @returns the breadcrumb trail
 */
export declare function createBreadcrumb<T>(aId: string, aSelParent: UnaryFunction<string, Observable<T>>, aSelId: UnaryFunction<T, string>): Observable<T[]>;
export {};