export type ThreadedWorkerMode = "sequential" | "parallel";
export interface UseThreadedWorkerOptions {
    /** Sequential: single worker, priority-ordered. Parallel: worker pool. */
    mode: ThreadedWorkerMode;
    /** Max concurrent workers. Only used when mode is "parallel". Default 4. */
    concurrency?: number;
}
export interface RunOptions {
    /** 1 = highest priority. Lower number runs first. FIFO within same priority. */
    priority?: number;
}
export interface UseThreadedWorkerReturn<TData, TResult> {
    /** Enqueue work. Returns a Promise that resolves with the worker result. */
    run: (data: TData, options?: RunOptions) => Promise<TResult>;
    /** True while any task is queued or running. */
    loading: boolean;
    /** Result of the most recently completed successful task. */
    result: TResult | undefined;
    /** Error from the most recently failed task. */
    error: unknown;
    /** Number of tasks currently queued + running. */
    queueSize: number;
    /** Clear all pending (not yet started) tasks. Running tasks continue. */
    clearQueue: () => void;
    /** Stop accepting new work and clear pending queue. Running tasks finish. */
    terminate: () => void;
}
/**
 * Production-grade hook to run async work in a queue with optional priority
 * and either sequential or parallel execution.
 *
 * @param workerFn - Async function to run for each task (e.g. API call, heavy compute).
 * @param options - mode: "sequential" | "parallel", concurrency (parallel only).
 * @returns run, loading, result, error, queueSize, clearQueue, terminate.
 */
export declare function useThreadedWorker<TData, TResult>(workerFn: (data: TData) => Promise<TResult>, options: UseThreadedWorkerOptions): UseThreadedWorkerReturn<TData, TResult>;