MacOs: How to select portion of screen and get CGRect (Position and coordinates) in Swift

I am trying to select a screen area/portion to record video of that portion but unfortunately, I haven't found any solution for that.

Here is my code to capture screenshot by selecting screen area,

        let task = Process()
        task.launchPath = "/usr/sbin/screencapture"
        task.arguments = ["-i", "-r", destinationPath]
        task.launch()
        task.waitUntilExit()

It lets the user select an area and capture that area of the screen. Now I want the same to record video of the selected portion of the screen like in Quicktime screen recording. Have been searching around the way to select screen area but got no success.

Any help would be appreciated!!