package Business::CreditCard::Obscure;

use strict;
use warnings;

sub new {

    my ($pack,%in) = @_;

    my $hash = {};

    $hash->{'cardnum'} = defined($in{'cardnum'}) ? $in{'cardnum'} : un
+def;
    $hash->{'head'} = defined($in{'head'}) ? $in{'head'} : 0;
    $hash->{'tail'} = defined($in{'tail'}) ? -$in{'tail'} : -4;
    $hash->{'replacement'} = defined($in{'replacement'}) ? $in{'replac
+ement'} : '*';

    return bless $hash, $pack;
}

sub obscure {

    my ($check,%in) = @_;
    my $self = ($check eq __PACKAGE__) ? $check->new(%in) : $check;

    $self->{'cardnum'} = $in{'cardnum'} if ($in{'cardnum'});
    $self->{'head'} = $in{'head'} if ($in{'head'});
    $self->{'tail'} = - $in{'tail'} if ($in{'tail'});
    $self->{'replacement'} = $in{'replacement'} if ($in{'replacement'}
+);

    return "cardnum not found" unless (defined($self->{'cardnum'}));
    return "head not found" unless (defined($self->{'head'}));
    return "tail not found" unless (defined($self->{'tail'}));
    return "replacement not found" unless (defined($self->{'replacemen
+t'}));

    my $cardnum = $self->{'cardnum'};

    substr(    $cardnum,
            $self->{'head'},
            $self->{'tail'}
            ) =~ s/./$self->{'replacement'}/g;

    return $self->{'obscured'} = $cardnum;

}

1;
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