import type { FolderNode } from '../../../../../../../shared/contracts/folders';
import type { DragItemData } from '../../../../types/dnd';
/**
 * Evaluate destination validity once for the full drag set. Callers look up
 * targets in O(1) via {@link Set.has} — `null` represents the Home/root drop.
 */
export declare const computeValidDropTargets: (items: DragItemData[], folderStructure: FolderNode[]) => Set<number | null>;