use warnings;
use strict;

use Tk;
use DateTime;
use Time::HiRes qw(time);

my $time;

# Specify the day you're counting down to here
my $then = DateTime->new(year => 2003, month => 12, day => 30, hour => 17,
                         minute => 30, second => 0, time_zone => 'local');

my $mw = MainWindow->new;
$mw->Label(-textvariable => \$time, -font => "{arial} 12 bold")->pack;

$mw->repeat(4, \&update);
update();

$mw->overrideredirect(1);
$mw->geometry("+0+0");

MainLoop;

sub update {
    my $now = DateTime->from_epoch(epoch => time, time_zone => 'local');

    my $dur = ($then - $now);
    $time =  $dur->days . " days  ";
    $time .= $dur->hours . ":";
    $time .= sprintf("%.2d", $dur->minutes) . ":";
    $time .= sprintf("%.2d", $dur->seconds) . ":";
    $time .= sprintf("%.3d", int($dur->nanoseconds / 1000000));
}