import { Observable } from "@babylonjs/core/Misc/observable";
import type { Nullable } from "@babylonjs/core/types";
import type { IDisposeObservable } from "../IDisposeObserable";
import type { IAudioPlayer } from "./IAudioPlayer";
/**
 * Audio element pool interface
 *
 * Pass to the constructor of `StreamAudioPlayer` to pool the audio element
 */
export interface IAudioElementPool {
    /**
     * Rent the audio element
     * @returns The audio element
     */
    rent(): HTMLAudioElement;
    /**
     * Return the audio element
     *
     * Returned audio element should not be used anymore
     * @param audioElement The audio element
     */
    return(audioElement: HTMLAudioElement): void;
}
/**
 * This class is used to pooling the audio element
 */
export declare class AudioElementPool implements IAudioElementPool {
    private readonly _audioElements;
    /**
     * Rent the audio element
     * @returns The audio element
     */
    rent(): HTMLAudioElement;
    /**
     * Return the audio element
     *
     * Returned audio element should not be used anymore
     * @param audioElement The audio element
     */
    return(audioElement: HTMLAudioElement): void;
}
/**
 * Stream audio player options
 */
export interface IStreamAudioPlayerOptions {
    /**
     * Whether to pooling the audio element
     *
     * If `true`, the `StreamAudioPlayer.DefaultAudioElementPool` is used as the audio element pool
     * If `false`, the audio element is created on demand
     * If `IAudioElementPool`, the specified audio element pool is used
     *
     * Default is `false`
     */
    pool?: boolean | IAudioElementPool;
}
/**
 * Stream audio player
 *
 * This class is used to play the audio from the stream
 *
 * It is suitable for playing long sounds because it plays even if all of the audio is not loaded
 *
 * Wrapper of `HTMLAudioElement` which handles audio playback permission issues gracefully
 */
export declare class StreamAudioPlayer implements IAudioPlayer {
    /**
     * Default global audio element pool instance
     */
    static readonly DefaultAudioElementPool: IAudioElementPool;
    /**
     * On load error observable
     *
     * This observable is notified when the audio load is failed
     */
    readonly onLoadErrorObservable: Observable<void>;
    /**
     * On duration changed observable
     *
     * This observable is notified when the audio duration is changed
     */
    readonly onDurationChangedObservable: Observable<void>;
    /**
     * On mute state changed observable
     *
     * This observable is notified when the mute state is changed
     */
    readonly onPlaybackRateChangedObservable: Observable<void>;
    /**
     * On mute state changed observable
     *
     * This observable is notified when the mute state is changed
     */
    readonly onMuteStateChangedObservable: Observable<void>;
    /**
     * On play observable
     *
     * This observable is notified when the player is played
     */
    readonly onPlayObservable: Observable<void>;
    /**
     * On pause observable
     *
     * This observable is notified when the player is paused
     */
    readonly onPauseObservable: Observable<void>;
    /**
     * On seek observable
     *
     * This observable is notified when the player is seeked
     */
    readonly onSeekObservable: Observable<void>;
    private readonly _pool;
    private _audio;
    private _duration;
    private _playbackRate;
    private _isVirtualPlay;
    private _virtualStartTime;
    private _virtualPaused;
    private _virtualPauseCurrentTime;
    private _metadataLoaded;
    private _disposeObserver;
    /**
     * Create a stream audio player
     *
     * In general disposeObservable should be `Scene` of Babylon.js
     *
     * @param disposeObservable Objects that limit the lifetime of this instance
     * @param options Options
     */
    constructor(disposeObservable: Nullable<IDisposeObservable>, options?: IStreamAudioPlayerOptions);
    private readonly _onDurationChanged;
    private readonly _onLoadError;
    private readonly _onPlay;
    private readonly _onPause;
    private _ignoreSeekedEventOnce;
    private readonly _onSeek;
    /**
     * Audio duration (in seconds)
     */
    get duration(): number;
    /**
     * Current time (in seconds)
     *
     * This property may be slow to update
     */
    get currentTime(): number;
    set currentTime(value: number);
    /** @internal */
    _setCurrentTimeWithoutNotify(value: number): void;
    /**
     * Volume (0.0 to 1.0)
     */
    get volume(): number;
    set volume(value: number);
    /**
     * Whether the audio is muted
     */
    get muted(): boolean;
    /**
     * Mute the audio
     */
    mute(): void;
    /**
     * Unmute the audio
     *
     * Unmute is possible failed if user interaction is not performed
     * @returns Whether the audio is unmuted
     */
    unmute(): Promise<boolean>;
    /**
     * Playback rate (0.07 to 16.0)
     */
    get playbackRate(): number;
    set playbackRate(value: number);
    /** @internal */
    _setPlaybackRateWithoutNotify(value: number): void;
    /**
     * Determines whether or not the browser should adjust the pitch of the audio to compensate for changes to the playback rate made by setting
     */
    get preservesPitch(): boolean;
    set preservesPitch(value: boolean);
    /**
     * Whether the player is paused
     */
    get paused(): boolean;
    /**
     * Audio source URL
     */
    get source(): string;
    set source(value: string);
    /**
     * Whether the audio metadata(durations) is loaded
     */
    get metadataLoaded(): boolean;
    private _virtualPlayAsync;
    private _playRequestBlocking;
    /**
     * Play the audio from the current position
     *
     * If context don't have permission to play the audio, play audio in a mute state
     */
    play(): Promise<void>;
    /**
     * Pause the audio
     */
    pause(): void;
    /**
     * Dispose the player
     */
    dispose(): void;
}