撤消/重做图像进度

Question

我有一个更改图片的功能，并且有两个取消/返回按钮 我为此写了3个功能 添加 撤消 重做 问题是，当我按2次撤消然后重做时，我的图像重做是两个步骤向前

我的代码

 public var undoHistory: [UIImage] = []
public var redoHistory: [UIImage] = []

public func undoImage() -> UIImage? {
    guard !(undoHistory.count == 1) else {
        return undoHistory.last
    }
    
    if let lastImage = undoHistory.last {
        redoHistory.append(lastImage)
        undoHistory.removeLast()
    }
    return undoHistory.last
}

public func addImageToHistory(_ image: UIImage) {
    undoHistory.append(image)

    guard !redoHistory.isEmpty else {
        return
    }
    redoHistory.removeAll()
}

public func redoImage() -> UIImage? {
    guard !(redoHistory.count == 1) else {
        return redoHistory.last
    }
    
    if let lastImage = redoHistory.last {
        redoHistory.removeLast()
        undoHistory.append(lastImage)
    }
    return redoHistory.last
}