如何检测AVQueuePlayer是否播放完毕？

let player = AVQueuePlayer()
let playerItem = AVPlayerItem(url: videoURL)
player.insert(playerItem, after: nil)

playerItem.addObserver(self, forKeyPath: "status", options: [.new, .initial], context: nil)

override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
    if keyPath == "status" {
        if let playerItem = object as? AVPlayerItem {
            if playerItem.status == .readyToPlay {
                // 播放器准备好播放
            } else if playerItem.status == .failed {
                // 播放器播放失败
            } else if playerItem.status == .unknown {
                // 播放器状态未知
            }
        }
    }
}

if player.items().count == 1 && player.currentItem?.status == .readyToPlay {
    // 播放完毕
}