import { AudioPlayer } from "./AudioPlayer";
/**
 * Plays an audio representation of a given message by converting the base64 payload (wav) to an ArrayBuffer
 * and then feeding this ArrayBuffer into the Web Audio API.
 *
 * To keep it simple this implementation makes the rather naive assumption that all messages that should be played
 * will be added to the queue before playing the first (initial) message is done.
 * This assumption is made to avoid complex Promise heavy code and/or a while loop that may completely block
 * the front-end.
 */
export declare class BufferedAudioPlayer implements AudioPlayer {
    /**
     * Singleton to prevent the existence of multiple audio players and therefore overlapping.
     * @returns {AudioPlayer}
     */
    static instance(): AudioPlayer;
    private static INSTANCE;
    private readonly queue;
    private readonly audioContext;
    private state;
    /**
     * Adds a message to the Queue and starts playing queued messages.
     * @param {Map<string, string>} message
     */
    play(message: any): void;
    private playAudio;
}