Mail rule to move messages with all-capital subject to Junk

I would like to create a rule on Mail that automatically moves any new e-mail message to the Junk folder if the subject contains all capital letters. I do not think that thanks to the Mail Rules it is possible to do that, but I am aware that it is possible to run an AppleScript for every new message (see screenshot below). Since I am not an expert with AppleScript, I was wondering whether it is possible to trigger an AppleScript that checks for any newly-arrived e-mail message subject and, if all uppercase, moves it to the Junk folder of the e-mail address.