Converting Line to Rectangle Automatically

Hello all,

I have a query as to how I could automate the replacing of selected individual lines with predetermined sized rectangular blocks centered on the line at the angle and on the “0” layer . See attached file:

Would anyone have any ideas as to go about this. The rectangle need not necessarily be a polyline, 4 single lines would be sufficient. And whether the original line is or is not replaced is unimportant either.

Image may be NSFW.
Clik here to view.Image may be NSFW.
Clik here to view.Image may be NSFW.
Clik here to view.Image may be NSFW.
Clik here to view.Image may be NSFW.
Clik here to view.

Image may be NSFW.
Clik here to view.