(* Demonstration MacOS/OSX app in AppleScript and Perl *)
(* Posted to perlmonks.org by Anonymous Monk 6/16/2018 *)
(* Node: How to write apps for macOS/OSX in Perl! Part 1: Perl ASN Check (Revised) *)
(* Changes: Refactored hard-coded variables and improved comments. *)

set TITLE to "Perl ASN Check"
set PROMPT to "Autonomous System Number:
(Example: 714 is Apple Inc. 666 does not exist. Blank to exit.)"
set ASQUERY to "https://freeapi.robtex.com/asquery/"

# EVENT LOOP
repeat
	# CONFIG LOOP
	repeat
		try
			# LET USER SET A VARIABLE
			set ASN to text returned of (display dialog PROMPT with title TITLE default answer "" buttons {"Check"} default button 1)

			# VERIFY NUMERIC INPUT, OR ELSE: ERROR
			set ASN to ASN as number # require a number
			exit repeat # continue if ASN is numeric
		on error # not a number?
			# CRITICAL ALERTS HAVE A SCARY ICON
			display alert "Please enter an Autonomous System Number!" as critical
		end try
		# END CONFIG
	end repeat
	
	if ASN is equal to 0 then return # exit if blank
	
	# ALL MACS HAVE PERL BABY!
	# SEND PERL STDOUT TO APPLESCRIPT VARIABLE
	set RES to do shell script "
		perl -MHTTP::Tiny -e '
			my $r = HTTP::Tiny->new->get(qq~" & ASQUERY & ASN & "~);
			if (length $r->{content}) {
				$r->{content} =~ /[0-9]+\\.[0-9]+\\.[0-9]+\\.[0-9]+/
				? print q~ASN (" & ASN & ") Exists!~ : print q~ASN (" & ASN & ") Not Found!~;
			}
			else {
				print q~Download failed! (" & ASQUERY & ")~
			}
		'
	"
	# PRINT PERL STDOUT TO DESKTOP ALERT VIA APPLESCRIPT VAR
	display alert RES
end repeat