Swift button画像位置の設定

enum ButtonEdgeInsetsStyle {
   case ButtonEdgeInsetsStyleTop // image ，label 
   case ButtonEdgeInsetsStyleLeft  // image ，label 
   case ButtonEdgeInsetsStyleBottom  // image ，label 
   case ButtonEdgeInsetsStyleRight // image ，label 
}

extension UIButton {
    func layoutButtonEdgeInsets(style:ButtonEdgeInsetsStyle,space:CGFloat) {
      var labelWidth : CGFloat = 0.0
      var labelHeight : CGFloat = 0.0
      var imageEdgeInset = UIEdgeInsetsZero
      var labelEdgeInset = UIEdgeInsetsZero
      let imageWith = self.imageView?.frame.size.width
      let imageHeight = self.imageView?.frame.size.height
      if Double(UIDevice.currentDevice().systemVersion) >= 8.0 {
           labelWidth = (self.titleLabel?.intrinsicContentSize().width)!
           labelHeight = (self.titleLabel?.intrinsicContentSize().height)!
      }else {
          labelWidth = (self.titleLabel?.frame.size.width)!
          labelHeight = (self.titleLabel?.frame.size.height)!
      }
      labelWidth = CGFloat(36)
      switch style {
      case .ButtonEdgeInsetsStyleTop:
          imageEdgeInset = UIEdgeInsetsMake(-labelHeight-space/2.0, 0, 0, -labelWidth)
          labelEdgeInset = UIEdgeInsetsMake(0, -imageWith!, -imageHeight!-space/2.0, 0)
      case .ButtonEdgeInsetsStyleLeft:
        imageEdgeInset = UIEdgeInsetsMake(0, -space/2.0, 0, space/2.0);
        labelEdgeInset = UIEdgeInsetsMake(0, space/2.0, 0, -space/2.0);
      case .ButtonEdgeInsetsStyleBottom:
          imageEdgeInset = UIEdgeInsetsMake(0, 0, -labelHeight-space/2.0, -labelWidth)
          labelEdgeInset = UIEdgeInsetsMake(-imageHeight!-space/2.0, -imageWith!, 0, 0)
      case .ButtonEdgeInsetsStyleRight:
          // To Do print(" ====\(labelWidth)=====\(space)")
          imageEdgeInset = UIEdgeInsetsMake(0, labelWidth+space/2.0, 0, -labelWidth-space/2.0)
          labelEdgeInset = UIEdgeInsetsMake(0, -imageWith!-space/2.0, 0, imageWith!+space/2.0)
      }
      self.titleEdgeInsets = labelEdgeInset
      self.imageEdgeInsets = imageEdgeInset
  }
}