import * as React from 'react';
import { IRectangle } from '../../Utilities';
import { List } from './List';
export interface IList {
    /**
     * Scroll to the given index. By default will bring the page the specified item is on into the view. If a callback
     * to measure the height of an individual item is specified, will only scroll to bring the specific item into view.
     *
     * Note: with items of variable height and no passed in `getPageHeight` method, the list might jump after scrolling
     * when windows before/ahead are being rendered, and the estimated height is replaced using actual elements.
     *
     * @param index Index of item to scroll to
     * @param measureItem Optional callback to measure the height of an individual item
     */
    scrollToIndex(index: number, measureItem?: (itemIndex: number) => number): void;
}
export interface IListProps extends React.HTMLAttributes<List | HTMLDivElement> {
    /**
     * Optional callback to access the IList interface. Use this instead of ref for accessing
     * the public methods and properties of the component.
     */
    componentRef?: (component: IList) => void;
    /** Optional classname to append to root list. */
    className?: string;
    /** Items to render. */
    items?: any[];
    /** Method to call when trying to render an item. */
    onRenderCell?: (item?: any, index?: number) => React.ReactNode;
    /** Optional callback for monitoring when a page is added. */
    onPageAdded?: (page: IPage) => void;
    /** Optional callback for monitoring when a page is removed. */
    onPageRemoved?: (page: IPage) => void;
    /** Optional callback to get the item key, to be used on render. */
    getKey?: (item: any, index?: number) => string;
    /** Method called by the list to get how many items to render per page from specified index. */
    getItemCountForPage?: (itemIndex?: number, visibleRect?: IRectangle) => number;
    /**
     * Method called by the list to get the pixel height for a given page. By default, we measure the first
     * page's height and default all other pages to that height when calculating the surface space. It is
     * ideal to be able to adequately predict page heights in order to keep the surface space from jumping
     * in pixels, which has been seen to cause browser performance issues.
     */
    getPageHeight?: (itemIndex?: number, visibleRect?: IRectangle) => number;
    /**
     * Method called by the list to derive the page style object. For spacer pages, the list will derive
     * the height and passed in heights will be ignored.
     */
    getPageStyle?: (page: IPage) => any;
    /**
     * In addition to the visible window, how many windowHeights should we render ahead.
     * @default 2
     */
    renderedWindowsAhead?: number;
    /**
     * In addition to the visible window, how many windowHeights should we render behind.
     * @default 2
     */
    renderedWindowsBehind?: number;
    /** Index in items array to start rendering from. Defaults to 0. */
    startIndex?: number;
    /** Number of items to render. Defaults to items.length. */
    renderCount?: number;
}
export interface IPage {
    key: string;
    items: any[];
    startIndex: number;
    itemCount: number;
    style: any;
    top: number;
    height: number;
}