/// <reference types="node" />
/**
 * The audio object of Web Audio API.
 *
 * @class
 * @param {string} url - The url of the audio file.
 */
export declare class WebAudio {
  name: string
  frameCount: number
  _url: string
  static _context: AudioContext | null
  static _masterGainNode: GainNode | null
  static _masterVolume: number
  _data: Uint8Array | null
  _fetchedSize: number
  _fetchedData: Uint8Array[]
  _buffers: AudioBuffer[]
  _sourceNodes: AudioBufferSourceNode[]
  _gainNode: GainNode | null
  _pannerNode: PannerNode | null
  _totalTime: number
  _sampleRate: number
  _loop: boolean
  _loopStart: number
  _loopLength: number
  _loopStartTime: number
  _loopLengthTime: number
  _startTime: number
  _volume: number
  _pitch: number
  _pan: number
  _endTimer: NodeJS.Timeout | null
  _loadListeners: Array<() => void>
  _stopListeners: Array<() => void>
  _lastUpdateTime: number
  _isLoaded: boolean
  _isError: boolean
  _isPlaying: boolean
  _decoder: VorbisDecoder | null
  constructor(url: string)
  /**
   * Initializes the audio system.
   *
   * @returns {boolean} True if the audio system is available.
   */
  static initialize(): boolean
  /**
   * Sets the master volume for all audio.
   *
   * @param {number} value - The master volume (0 to 1).
   */
  static setMasterVolume(value: number): void
  static _createContext(): void
  static _currentTime(): number
  static _createMasterGainNode(): void
  static _setupEventHandlers(): void
  static _onUserGesture(): void
  static _onVisibilityChange(): void
  static _onHide(): void
  static _onShow(): void
  static _shouldMuteOnHide(): boolean
  static _resetVolume(): void
  static _fadeIn(duration: number): void
  static _fadeOut(duration: number): void
  /**
   * Clears the audio data.
   */
  clear(): void
  /**
   * The url of the audio file.
   *
   * @readonly
   * @type string
   * @name WebAudio#url
   */
  get url(): string
  /**
   * The volume of the audio.
   *
   * @type number
   * @name WebAudio#volume
   */
  get volume(): number
  set volume(value: number)
  /**
   * The pitch of the audio.
   *
   * @type number
   * @name WebAudio#pitch
   */
  get pitch(): number
  set pitch(value: number)
  /**
   * The pan of the audio.
   *
   * @type number
   * @name WebAudio#pan
   */
  get pan(): number
  set pan(value: number)
  /**
   * Checks whether the audio data is ready to play.
   *
   * @returns {boolean} True if the audio data is ready to play.
   */
  isReady(): boolean
  /**
   * Checks whether a loading error has occurred.
   *
   * @returns {boolean} True if a loading error has occurred.
   */
  isError(): boolean
  /**
   * Checks whether the audio is playing.
   *
   * @returns {boolean} True if the audio is playing.
   */
  isPlaying(): boolean
  /**
   * Plays the audio.
   *
   * @param {boolean} loop - Whether the audio data play in a loop.
   * @param {number} offset - The start position to play in seconds.
   */
  play(loop: boolean, offset?: number): void
  /**
   * Stops the audio.
   */
  stop(): void
  /**
   * Destroys the audio.
   */
  destroy(): void
  /**
   * Performs the audio fade-in.
   *
   * @param {number} duration - Fade-in time in seconds.
   */
  fadeIn(duration: number): void
  /**
   * Performs the audio fade-out.
   *
   * @param {number} duration - Fade-out time in seconds.
   */
  fadeOut(duration: number): void
  /**
   * Gets the seek position of the audio.
   */
  seek(): number
  /**
   * Adds a callback function that will be called when the audio data is loaded.
   *
   * @param {function} listner - The callback function.
   */
  addLoadListener(listner: () => void): void
  /**
   * Adds a callback function that will be called when the playback is stopped.
   *
   * @param {function} listner - The callback function.
   */
  addStopListener(listner: () => void): void
  /**
   * Tries to load the audio again.
   */
  retry(): void
  _startLoading(): void
  _shouldUseDecoder(): boolean
  _createDecoder(): void
  _destroyDecoder(): void
  _realUrl(): string
  _startXhrLoading(url: string): void
  _startFetching(url: string): void
  _onXhrLoad(xhr: XMLHttpRequest): void
  _onFetch(response: Response): void
  _onError(): void
  _onFetchProcess(value: Uint8Array): void
  _updateBufferOnFetch(): void
  _concatenateFetchedData(): void
  _updateBuffer(): void
  _readableBuffer(): ArrayBufferLike
  _decodeAudioData(arrayBuffer: ArrayBuffer): void
  _onDecode(buffer: AudioBuffer): void
  _refreshSourceNode(): void
  _startPlaying(offset: number): void
  _startAllSourceNodes(): void
  _startSourceNode(index: number): void
  _stopSourceNode(): void
  _createPannerNode(): void
  _createGainNode(): void
  _createAllSourceNodes(): void
  _createSourceNode(index: number): void
  _removeNodes(): void
  _createEndTimer(): void
  _removeEndTimer(): void
  _updatePanner(): void
  _onLoad(): void
  _readLoopComments(arrayBuffer: ArrayBuffer): void
  _readMetaData(view: DataView, index: number, size: number): void
  _readFourCharacters(view: DataView, index: number): string
}