use DateTime;

use strict;
use warnings;

my $dt = DateTime->now();

# Dow starts with Monday
my %delta = (1 => -2, 2 => -3, 3 => 3, 4 => 2, 5 => 1, 6 => 0, 7 => -1);

my $saturday = $dt->add(days => $delta{$dt->day_of_week});

print $saturday, "\n";