import type { Key } from '@react-types/shared';
import type { dh } from '@deephaven/jsapi-types';
import { type KeyedItem } from '@deephaven/utils';
export declare const ITEM_KEY_PREFIX = "DH_ITEM_KEY";
export type OnTableUpdatedEvent = dh.Event<{
    offset: number;
    columns: dh.Column[];
    rows: dh.Row[];
}>;
export type RowDeserializer<T> = (row: dh.Row, columns: dh.Column[]) => T;
/**
 * Create a `KeyedItem.key` for a given index. The prefix is necessary to avoid
 * collisions with property values in the `item` property that may be used as
 * keys once the item is loaded and rendered.
 * @param index Index to create a key for.
 * @returns A unique key for the given index.
 */
export declare function createKeyedItemKey(index: number): string;
/**
 * Creates a handler function for a `dh.Table.EVENT_UPDATED` event. Rows that
 * get passed to the handler will be bulk updated in the given `viewportData`
 * object based on their derived item keys.
 * @param viewportData State object for managing a list of KeyedItem data.
 * @param deserializeRow Converts a DH Row to an item object.
 * @returns Handler function for a `dh.Table.EVENT_UPDATED` event.
 */
export declare function createOnTableUpdatedHandler<T>({ bulkUpdate }: {
    bulkUpdate: (itemMap: Map<Key, KeyedItem<T>>) => void;
}, deserializeRow: RowDeserializer<T>): (event: OnTableUpdatedEvent) => void;
/**
 * Maps a Row to a key / value object. Keys are mapped ver batim from column
 * names.
 * @param row Row to map to an item.
 * @param columns Columns to map.
 * @returns A key / value object for the row.
 */
export declare function defaultRowDeserializer<T>(row: dh.Row, columns: dh.Column[]): T;
/**
 * For windowing to work, the underlying list needs to maintain a KeyedItem for
 * each row in the backing table (even if these rows haven't been loaded yet).
 * This is needed internally by react-spectrum so it can calculate the content
 * area size. This generator can create a range of empty `KeyedItem` objects.
 * @param start The starting index to generate
 * @param end The ending index to generate
 */
export declare function generateEmptyKeyedItems<T>(start: number, end: number): Generator<KeyedItem<T>, void, unknown>;
/**
 * Check a Table to see if it is closed before checking its size property. This
 * is important because calling Table.size on a closed table throws an error. If
 * the table is null or closed, return zero. Otherwise, return the current size.
 * @param table The table to check for its size.
 * @returns The size of the table or zero if the table is null or closed.
 */
export declare function getSize(table?: dh.Table | dh.TreeTable | null): number;
/**
 * Check if a given widget is closed based on `isClosed` prop.
 * Tree tables and other widgets don't have an `isClosed` prop,
 * so will always return false.
 * @param table The widget to check if it is closed.
 */
export declare function isClosed(widget: unknown): boolean;
/**
 * Determine the first and last row index for a viewport + extra leading and
 * trailing padding. Values will be "clamped" to stay within the table size.
 * @param firstRow Starting row index for the viewport.
 * @param viewportSize Size of the viewport.
 * @param padding Extra rows to add to the viewport. Will be used for leading
 * and trailing rows.
 * @param tableSize Total table size.
 * @returns Tuple containing indices for the first and last row.
 */
export declare function padFirstAndLastRow(firstRow: number, viewportSize: number, padding: number, tableSize: number): [number, number];
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