#!/usr/bin/perl

use strict;
use warnings;

use MY::CLI;
MY::CLI->run;

package MY::CLI;
use App::Cmd::Setup -app;

1;

package MY::CLI::Command::Date;

use strict;
use warnings;

use MY::CLI -command;
use Time::Piece;

sub abstract {
    return "Give information about a date";
}

sub usage_desc {
    return "cli.pl Date --date <date>";
}

sub opt_spec {
    return (
        [ 'date=s', 'A date you want information about' ],
    );
}

sub validate_args {}

sub execute {
    my ($self, $opt, $args) = @_;

    if ( !$opt->{date} ) {
        print $self->usage->text;
        return;
    }

    my $time = Time::Piece->strptime( $opt->{date}, '%Y-%m-%d' );
    print sprintf "Datum: %s
KW: %s
Schaltjahr: %s\n", $time->dmy('.'), $time->week, $time->is_leap_year;
}

1;

$ perl cli.pl
Available commands:

  commands: list the application's commands
      help: display a command's help screen

      date: Give information about a date

$ perl cli.pl date
cli.pl Date --date <date>
	--date      A date you want information about
$ perl cli.pl date --date 2012-09-18
Datum: 18.09.2012
KW: 38
Schaltjahr: 1
$ perl cli.pl date --date 2014-09-18
Datum: 18.09.2014
KW: 38
Schaltjahr: 0