import { Store, StoreValue } from '@ngneat/elf';
export interface StateHistoryOptions<State> {
    maxAge: number;
    comparatorFn: (prevState: State, currentState: State) => boolean;
    resetFutureOnNewState?: boolean;
}
declare type History<State> = {
    past: State[];
    present: State | null;
    future: State[];
};
export declare class StateHistory<T extends Store, State extends StoreValue<T>> {
    protected store: T;
    private options;
    private paused;
    private history;
    private skipUpdate;
    private subscription;
    private hasPastSubject;
    private hasFutureSubject;
    private mergedOptions;
    hasPast$: import("rxjs").Observable<boolean>;
    hasFuture$: import("rxjs").Observable<boolean>;
    constructor(store: T, options?: Partial<StateHistoryOptions<State>>);
    get hasPast(): boolean;
    get hasFuture(): boolean;
    getPast(): History<State>['past'];
    getFuture(): History<State>['future'];
    activate(): void;
    undo(): void;
    redo(): void;
    jumpToPast(index: number): void;
    jumpToFuture(index: number): void;
    /**
     *
     * jump n steps in the past or forward
     *
     */
    jump(n: number): void;
    /**
     *
     * Clear the history
     *
     * @param customUpdateFn Callback function for only clearing part of the history
     *
     * @example
     *
     * stateHistory.clear((history) => {
     *  return {
     *    past: history.past,
     *    present: history.present,
     *    future: []
     *  };
     * });
     */
    clear(customUpdateFn?: (history: History<State>) => History<State>): void;
    destroy({ clearHistory }?: {
        clearHistory?: boolean;
    }): void;
    pause(): void;
    resume(): void;
    private update;
    private updateHasHistory;
}
export declare function stateHistory<T extends Store, State extends StoreValue<T>>(store: T, options?: Partial<StateHistoryOptions<State>>): StateHistory<T, State>;
export {};