import type { WidgetChangeEvent } from './change-events';
import type { WidgetProps } from './components/widget/types';
/**
 * Reduces a WidgetChangeEvent to a Partial<WidgetProps> delta for state merge.
 *
 * Pure, allocation-only; no mutation. Used by the composition layer (e.g. useComposedDashboard)
 * to translate atomic events into prop updates.
 *
 * Validates that the event payload structure matches the widget type before applying.
 * Returns empty delta when payload structure is incompatible (e.g. chart array payload
 * for a pivot widget), avoiding silent corruption.
 *
 * @param event - The widget change event
 * @param currentWidget - The current widget state
 * @returns A partial props object to merge into the widget
 */
export declare function widgetChangeEventToDelta(event: WidgetChangeEvent, currentWidget: WidgetProps): Partial<WidgetProps>;