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export interface StickToBottomState {
    scrollTop: number;
    lastScrollTop?: number;
    ignoreScrollToTop?: number;
    targetScrollTop: number;
    calculatedTargetScrollTop: number;
    scrollDifference: number;
    resizeDifference: number;
    animation?: {
        behavior: "instant" | Required<SpringAnimation>;
        ignoreEscapes: boolean;
        promise: Promise<boolean>;
    };
    lastTick?: number;
    velocity: number;
    accumulated: number;
    escapedFromLock: boolean;
    isAtBottom: boolean;
    isNearBottom: boolean;
    resizeObserver?: ResizeObserver;
}
declare const DEFAULT_SPRING_ANIMATION: {
    /**
     * A value from 0 to 1, on how much to damp the animation.
     * 0 means no damping, 1 means full damping.
     *
     * @default 0.7
     */
    damping: number;
    /**
     * The stiffness of how fast/slow the animation gets up to speed.
     *
     * @default 0.05
     */
    stiffness: number;
    /**
     * The inertial mass associated with the animation.
     * Higher numbers make the animation slower.
     *
     * @default 1.25
     */
    mass: number;
};
export interface SpringAnimation extends Partial<typeof DEFAULT_SPRING_ANIMATION> {
}
export type Animation = ScrollBehavior | SpringAnimation;
export interface ScrollElements {
    scrollElement: HTMLElement;
    contentElement: HTMLElement;
}
export type GetTargetScrollTop = (targetScrollTop: number, context: ScrollElements) => number;
export interface StickToBottomOptions extends SpringAnimation {
    resize?: Animation;
    initial?: Animation | boolean;
    targetScrollTop?: GetTargetScrollTop;
}
export type ScrollToBottomOptions = ScrollBehavior | {
    animation?: Animation;
    /**
     * Whether to wait for any existing scrolls to finish before
     * performing this one. Or if a millisecond is passed,
     * it will wait for that duration before performing the scroll.
     *
     * @default false
     */
    wait?: boolean | number;
    /**
     * Whether to prevent the user from escaping the scroll,
     * by scrolling up with their mouse.
     */
    ignoreEscapes?: boolean;
    /**
     * Only scroll to the bottom if we're already at the bottom.
     *
     * @default false
     */
    preserveScrollPosition?: boolean;
    /**
     * The extra duration in ms that this scroll event should persist for.
     * (in addition to the time that it takes to get to the bottom)
     *
     * Not to be confused with the duration of the animation -
     * for that you should adjust the animation option.
     *
     * @default 0
     */
    duration?: number | Promise<void>;
};
export type ScrollToBottom = (scrollOptions?: ScrollToBottomOptions) => Promise<boolean> | boolean;
export type StopScroll = () => void;
export declare const useStickToBottom: (options?: StickToBottomOptions) => StickToBottomInstance;
export interface StickToBottomInstance {
    contentRef: React.MutableRefObject<HTMLElement | null> & React.RefCallback<HTMLElement>;
    scrollRef: React.MutableRefObject<HTMLElement | null> & React.RefCallback<HTMLElement>;
    scrollToBottom: ScrollToBottom;
    stopScroll: StopScroll;
    isAtBottom: boolean;
    isNearBottom: boolean;
    escapedFromLock: boolean;
    state: StickToBottomState;
}
export {};