#!/usr/bin/perl
use warnings;
use strict;

print "Enter 
       a for lowercase and colons.
       b to do it the other way around.
       q to quit ";
my $choice = 0;
my $wwn = 0;
chomp ($choice = <STDIN>);
if ($choice eq "a")
{
    until ( $wwn eq "q")
        {
            print "Enter the wwn or q to quit: ";
            chomp ($wwn=<STDIN>);
            if ($wwn=~m/:/g)
                {
	               print "WWN already contains :\n";
	               exit;
               
                 }#closing for if ($wwn=~m/:/g)
elsif (length($wwn)!=16)
{
	print "Invalid WWN Length\n";
	exit;
}#closing for elsif (length($wwn)!=16)
else
{
    my @wwn = unpack ("(a2)*", lc($wwn));
    @wwn = join (":", @wwn);
    print "@wwn\n";  
} #closing for lowering case and adding : in wwn.
}#closing for until ( $wwn eq "q")
}#closing for if choice =a

elsif ($choice eq "b")
{
    until ($wwn eq "q")
    {
	
        print "Enter the wwn with : or q to quit: ";
        chomp ($wwn=<STDIN>);
        $wwn =~ s/://g;
        print lc($wwn), "\n";
    } #closing for until ($wwn eq "q")
}#closing for if choice =b
elsif ($choice eq "q")
{
	exit;
}#closing for elsif ($choice eq "q")