import { FilterBarReducerAction } from '../types/filter-state.js';
import { FilterState, PinnedState } from '../types/shared-filter-types.js';
/**
 * FilterBar reducer function used for managing the state of the filter items.
 * It keeps track of the currently applied filters and the pinned state of all filter items.
 * Both states are maintained independently of each other and can be synced with their own actions.
 */
export declare function reducer(state: FilterState, action: FilterBarReducerAction, hasControlledPinnedState: boolean, onPinnedStateChange?: (newState: PinnedState, changedItems: Array<string | number>) => void): FilterState;