import { UsermavenClient } from '../core/client';
export declare class ScrollDepth {
    private client;
    private maxScrollDepth;
    private milestones;
    private lastScrollDepth;
    private documentElement;
    private debouncedHandleScroll;
    constructor(client: UsermavenClient);
    private initializeEventListener;
    track(): void;
    send(eventType?: string): void;
    private handleScroll;
    private getScrollDepth;
    private getWindowHeight;
    private getDocumentHeight;
    private getScrollDistance;
    private checkMilestones;
    destroy(): void;
}