import { ElementRef } from '@angular/core';
import { Observable } from 'rxjs';
import { SpyTarget } from './spy-target.model';
import { WindowService } from './window.service';
import * as i0 from "@angular/core";
export declare class ScrollSpyService {
    private windowService;
    private stopSpying$;
    private activeSpyTarget$;
    private scrollEvent;
    private resizeEvent;
    private spyTargets;
    private thresholdTop;
    private thresholdBottom;
    private scrollContainer;
    private isSpying;
    constructor(windowService: WindowService);
    spy({ scrollContainer, thresholdTop, thresholdBottom }?: SpyOptions): void;
    addTarget(target: SpyTarget): void;
    removeTarget(target: string): void;
    checkActiveElement(scrollContainer?: ElementRef): void;
    isElementActive(element: ElementRef, scrollContainer?: ElementRef, scrollContainerOffset?: number, currentActiveElement?: ElementRef): boolean;
    private getTotalOffset;
    private isElementInsideWindow;
    get activeSpyTarget(): Observable<string>;
    stopSpying(): void;
    static ɵfac: i0.ɵɵFactoryDeclaration<ScrollSpyService, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<ScrollSpyService>;
}
interface SpyOptions {
    scrollContainer?: ElementRef;
    thresholdTop?: number;
    thresholdBottom?: number;
}
export {};