import { type Ref } from "vue";
import type { CompositeFilterDescriptor } from "@progress/kendo-data-query";
/**
 * Returns a reactive function that resolves to `"active"` when the given
 * field has a filter applied in the current filter tree, or `""` when it
 * does not.
 *
 * Bind the returned function directly to column `headerClassName` inside a
 * `computed` — Vue tracks the `filterRef` dependency automatically; no
 * manual update call is needed.
 *
 * @param filterRef - Reactive grid filter descriptor (the same ref bound to the Grid).
 * @returns `(field: string) => "active" | ""`
 *
 * @example
 * const activeClass = useGridActiveFilter(filterRef);
 *
 * const columns = computed(() => [
 *   { field: "ProductName", headerClassName: activeClass("ProductName") },
 * ]);
 */
export declare const useGridActiveFilter: (filterRef: Ref<CompositeFilterDescriptor | undefined>) => ((field: string) => string);