use Date::Manip qw[ ParseDate UnixDate ];
use Data::Dumper;

$ENV{TZ} = 'PST';

my @date = UnixDate( ParseDate("today"), qw[%Y %m %d %W ] );
print join "|",@date,$/;

print join "|",UnixDate( ParseDate("$date[3] week $date[0]"), qw[%Y %m %d %W ] ),$/;
print join "|",UnixDate( ParseDate(1+$date[3]." week $date[0]"), qw[%Y %m %d %W ] ),$/;