export interface IUtterance extends SpeechSynthesisUtterance {
    id: string;
}
export type IUtteranceStatus = 'idle' | 'speaking' | 'ended' | 'error';
export interface IUtteranceOptions {
    volume?: number;
    rate?: number;
    pitch?: number;
    lang?: string;
    voice?: SpeechSynthesisVoice;
    onstart?: () => void;
    onend?: () => void;
    onerror?: () => void;
    onpause?: () => void;
    onresume?: () => void;
    onmark?: () => void;
    onboundary?: () => void;
}
/**
 * A class that represents a speech synthesis utterance
 * It is a wrapper around the SpeechSynthesisUtterance class
 */
export declare class Utterance {
    id: string;
    utterance?: SpeechSynthesisUtterance;
    retryCount: number;
    error: string | null;
    status: IUtteranceStatus;
    userOptions: IUtteranceOptions;
    text: string;
    rate: number;
    volume: number;
    pitch: number;
    lang: string;
    voice: SpeechSynthesisVoice;
    mark: SpeechSynthesisEvent | null;
    /**
     * It marks the character position that has been read by the speech
     * synthesis engine.
     */
    readerIndex: number;
    read: string;
    unread: string;
    constructor(id: string, text: string, options?: IUtteranceOptions);
    restart: () => void;
    setVolume: (volume: number) => void;
    setRate: (rate: number) => void;
    setMark: (mark: string) => void;
    setVoice: (voice: SpeechSynthesisVoice) => void;
    setPitch: (pitch: number) => void;
    setReaderIndex: (index: number) => void;
    /**
     * Increments the retry count
     */
    setRetry: () => void;
    private setUtteranceOptions;
    private isNotOfOverwrittenValues;
    private setUtterance;
    setRead: (read: string) => void;
    setUnread: (unread: string) => void;
    /**
     * Sets the status of the utterance.
     * Possible values: idle, active, ended, error.
     * Use idle when the utterance has been created but not started.
     * Use active when the utterance is being spoken.
     * Use ended when the utterance has finished being spoken.
     * Use error when the utterance has encountered an error.
     * @param status IUtteranceStatus
     */
    private setStatus;
    /**
     * Sets the error property in this utterance
     * @param error the error
     */
    private setError;
    /**
     * Sets the text property in this utterance.
     * This is the text that will be spoken.
     * @param text the text to speak
     */
    setText: (text: string) => void;
}