export interface StateChangeHandler {
    (event: {
        state: 'done';
    }): void;
    (event: {
        state: 'queue';
    }): void;
    (event: {
        state: 'error';
        reason: string;
    }): void;
    (event: {
        state: 'progress';
        progress: number;
    }): void;
}
export declare class FileUploadManager {
    private dataChannel;
    private readonly chunkSize;
    private highWaterMark;
    private uploadQueue;
    private fileUploadHandlerMap;
    private stateHandlerMap;
    private cdPromiseMap;
    private gap;
    private paused;
    private sending;
    private get ready();
    private get bufferedAmount();
    constructor(dataChannel: RTCDataChannel);
    private handleClose;
    private handleMessage;
    private handleBufferedAmountLow;
    private sendData;
    /**
     * @description resume upload after dataChannel recreate
     */
    resume(dataChannel: RTCDataChannel): void;
    recomputeHighWaterMark: (latency: number) => void;
    upload(file: File, onStateChange?: StateChangeHandler): void;
    changeDirectory(path?: string, replace?: boolean): Promise<boolean>;
    destroy(): void;
}