/**
 * @license
 *-------------------------------------------------------------------------------------------
 * Copyright © 2026 Progress Software Corporation. All rights reserved.
 * Licensed under commercial license. See LICENSE.md in the package root for more information
 *-------------------------------------------------------------------------------------------
 */
import { RowHeightService } from '@progress/kendo-react-common';
import { GroupState } from '@progress/kendo-react-data-tools';
import { DataItemWrapper } from '../utils/index.js';
import * as React from 'react';
/**
 * @hidden
 * Represents the range of a group within the flat data array.
 */
export interface GroupRange {
    headerIndex: number;
    footerIndex: number | null;
    firstChildIndex: number;
    lastChildIndex: number;
    level: number;
}
/**
 * @hidden
 * Builds a map of group ranges from the flat data array.
 * Each group header maps to its footer and child range.
 */
export declare function buildGroupRangeMap(flatDataArray: DataItemWrapper[]): Map<number, GroupRange>;
/**
 * @hidden
 * Pairs a DataItemWrapper with its flat-data index.
 */
export interface StickyGroupItem {
    item: DataItemWrapper;
    flatIndex: number;
}
/**
 * @hidden
 */
export declare function computeStickyItems(flatDataArray: DataItemWrapper[], groupRanges: Map<number, GroupRange>, firstVisibleIndex: number, lastVisibleIndex: number, rawFirstVisibleIndex?: number): StickyGroupItem[];
/**
 * @hidden
 * Computes which group footers should be sticky at the bottom of the viewport.
 * A footer is sticky when it is scrolled below the viewport but its group's
 * header (or first child) is still visible above.
 */
export declare function computeStickyFooterItems(flatDataArray: DataItemWrapper[], groupRanges: Map<number, GroupRange>, firstVisibleIndex: number, lastVisibleIndex: number): StickyGroupItem[];
/**
 * @hidden
 * Hook that computes which group header/footer should be sticky
 * based on the scroll position and the flat data array.
 * Uses refs + direct DOM manipulation to avoid render-cycle flicker.
 */
export declare function useStickyGroups(options: {
    enabled: boolean;
    enabledFooters?: boolean;
    flatData: DataItemWrapper[];
    containerRef: React.RefObject<HTMLDivElement | null>;
    tableBodyRef: React.RefObject<HTMLTableSectionElement | null>;
    rowHeight?: number;
    isGrouped: boolean;
    virtualSkipRef?: React.RefObject<number>;
    rowHeightServiceRef?: React.RefObject<RowHeightService | undefined>;
}): {
    stickyHeaderItems: StickyGroupItem[];
    stickyHeaderRef: React.RefObject<HTMLDivElement | null>;
    stickyFooterItems: StickyGroupItem[];
    stickyFooterRef: React.RefObject<HTMLDivElement | null>;
    scrollToStickyGroup: (group: GroupState) => void;
    update: () => void;
};