import { PipelineConfig, PreloadConfig, WorkerConfig } from './config-types';
import { WorkerGeneratedResult } from './generator-types';
/**
 * Worker manager class to handle the initialization and termination of the segmenation
 * web worker. This class is responsible for loading the worker script, resolving the
 * configuration, and managing the worker lifecycle. It also provides methods to
 * preload the worker and terminate it when no longer needed.
 */
export declare class WorkerManager {
    private worker?;
    private workerUrl?;
    private destroyPromise;
    private onInitializedCallbacks;
    private onGeneratedCallbacks;
    private onDroppedCallbacks;
    private onLogCallbacks;
    /**
     * Get the current worker instance.
     *
     * @returns The current worker instance or undefined if not initialized.
     */
    getWorker(): Worker | undefined;
    /**
     * Initialize the worker using the provided configuration.
     *
     * @param config - The configuration object.
     * @returns A promise that resolves when the worker is initialized.
     */
    initializeWorker(config: WorkerConfig): Promise<Worker>;
    /**
     * Destroys the worker gracefully by sending a destroy message and waiting for confirmation.
     *
     * @returns A promise that resolves when the worker is destroyed.
     *          If no worker is available, it resolves immediately.
     */
    destroyWorker(): Promise<void>;
    /**
     * Terminate the worker.
     */
    terminateWorker(): void;
    /**
     * Preload the worker using the provided configuration.
     *
     * @param config - The configuration object.
     * @returns A promise that resolves when the worker is preloaded.
     */
    preloadWorker(config: PreloadConfig): Promise<void>;
    /**
     * Prepare the worker configuration by resolving the final URLs and paths to send to the
     * worker. This is necessary because we can't send functions to the worker. We also need to
     * remove the assetUrlResolver function from the configuration.
     *
     * @param config - The preload configuration.
     * @returns The worker configuration.
     */
    prepareWorkerConfig(config: PreloadConfig): Promise<any>;
    /**
     * Register a callback for when the worker is initialized.
     */
    onInitialized(callback: () => void): void;
    /**
     * Register a callback for when the worker generates output.
     *
     * @param callback - The callback function to be called with the generated data.
     * @param data - The generated data from the worker.
     * @param data.mask - The generated mask.
     * @param data.facesAndLandmarks - The detected faces and landmarks.
     * @param data.gesture - The detected gesture.
     * @param data.motion - The detected motion.
     */
    onGenerated(callback: (data: WorkerGeneratedResult) => void): void;
    /**
     * Register a callback for when the worker drops a frame.
     * This is useful for handling cases where the worker cannot keep up with the input frame rate.
     * The callback will be called with the timestamp of the dropped frame.
     *
     * @param callback - The callback function to be called with the timestamp of the dropped frame.
     */
    onDropped(callback: (timestamp: number) => void): void;
    /**
     * Register a callback for log messages from the worker.
     *
     * @param callback - The callback function to be called with the log message and severity.
     * @param severity - The severity of the log message (e.g., 'info', 'warn', 'error').
     */
    onLog(callback: (message: string, severity: string) => void): void;
    /**
     * Send an init message to the worker.
     *
     * @param config - The configuration object to initialize the worker.
     * @param config.baseUrl - The base URL for loading assets.
     * @param config.input - The input configuration for the worker.
     * @param config.mask - The mask configuration for the worker.
     * @param config.wasmUri - The URI for the WebAssembly module.
     * @param config.workerUri - The URI for the worker script.
     * @param config.assetUrlResolver - The function to resolve asset URLs.
     */
    sendInit(config: PipelineConfig): void;
    /**
     * Send a generate message to the worker.
     *
     * @param input - The input image data as a Uint8ClampedArray.
     * @param timestamp - The timestamp of the input image.
     */
    sendGenerate(input: Uint8ClampedArray, timestamp: number): void;
}
export declare const workerManager: WorkerManager;