import { Ref } from '../../node_modules/vue';
/**
 * Data a chart can be fed: an array of rows, a keyed record of numbers, a URL
 * string to fetch from, or `null` before anything is provided.
 */
export type ChartData = Record<string, unknown>[] | Record<string, number> | string | null;
/**
 * Data a chart holds once loading has settled: the inline value passed through,
 * or the parsed result of a fetched URL, narrowed to the caller's own datum
 * shape `T` (e.g. `BarChartDatum[]`), or `null` before the first load.
 */
export type LoadedData<T = Record<string, unknown>[] | Record<string, number>> = T | null;
/**
 * Reactive inputs driving {@link useChartData}: the raw chart data and the file
 * format to parse when that data is a URL.
 */
export interface UseChartDataOptions {
    data: Ref<ChartData>;
    dataUrlType: Ref<'json' | 'csv' | 'tsv'>;
}
/**
 * Reactive API returned by {@link useChartData}.
 */
export interface UseChartData<T = Record<string, unknown>[] | Record<string, number>> {
    /**
     * The chart's resolved data: inline data passed through, or the parsed result
     * of a fetched URL. `null` until the first load settles.
     */
    loadedData: Ref<LoadedData<T>>;
}
/**
 * Owns a chart's data-loading concern: it watches the data and format inputs
 * and, whenever they change, either fetches and parses a URL through d3 or
 * passes inline data through untouched. A caller-supplied `onLoaded` hook is
 * awaited after each settled load so the parent can run its own side effects
 * (emitting events, sizing) in a predictable order.
 *
 * @param options - The reactive data and URL-type inputs (see {@link UseChartDataOptions}).
 * @param onLoaded - Hook awaited after every settled load, receiving the freshly loaded data.
 * @returns The {@link UseChartData} API exposing `loadedData`.
 * @remarks Internal building block consumed by {@link useChart}; not exported from the package root.
 * @example
 * // Inside useChart, wiring the load hook to lifecycle events:
 * import { useChartData } from '@/composables/useChartData'
 *
 * const { loadedData } = useChartData(
 *   { data: props.data, dataUrlType: props.dataUrlType },
 *   async (data) => {
 *     // simplified — see useChart for the full load→emit ordering
 *     // (afterLoaded → isLoaded → emit('loaded') → onResized → emit('resized'))
 *     await afterLoaded?.()
 *     emit('loaded', data)
 *   }
 * )
 */
export declare function useChartData<T = Record<string, unknown>[] | Record<string, number>>(options: UseChartDataOptions, onLoaded: (data: LoadedData<T>) => void | Promise<void>): UseChartData<T>;
export default useChartData;