Interface PlayerWrapper

interface PlayerWrapper {
    duration: () => number;
    fade: (from: number, to: number, duration: number) => void;
    mute: (muted?: boolean) => boolean;
    off: (event: string, callback?: () => void) => void;
    on: (event: string, callback: () => void) => void;
    once: (event: string, callback: () => void) => void;
    pause: () => void;
    play: () => void;
    seek: (position: number) => void;
    state: () => string;
    stop: () => void;
    unload: () => void;
    volume: (vol?: number) => number;
}