fileprivate func invalidatePlayback(shouldResetIndex resetIndex: Bool = true) {
    stopProgressTimer()
    radioPlayer?.pause()
    radioPlayer?.rate = 0.0
    state = .paused
    radioPlayer = nil

    if resetIndex {
        playIndex = 0
    }
}

fileprivate func startNewPlayer(forItem item : AVPlayerItem) {
    invalidatePlayback(shouldResetIndex: false)
    radioPlayer = AVPlayer(playerItem: item)
    radioPlayer?.allowsExternalPlayback = false
    radioPlayer?.rate = 1.0
    startProgressTimer()
    seek(toSecond: 0, shouldPlay: true)
    updateInfoCenter()
}