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package Algorithm::CheckDigits::M11_012;
use 5.006;
use strict;
use warnings;
use integer;
our @ISA = qw(Algorithm::CheckDigits);
my @weight = ( 2,3,4,5,6,7,1,6,7,2,3 );
my %table_to = (
0 => 0, 1 => 1, 2 => 2, 3 => 3, 4 => 4, 5 => 5,
6 => 6, 7 => 7, 8 => 8, 9 => 9, A => 12, B => 14,
C => 16, D => 18, E => 20, F => 22, G => 24, H => 26,
I => 28, J => 6, K => 8, L => 10, M => 12, N => 14,
O => 16, P => 18, Q => 20, R => 22, S => 4, T => 6,
U => 8, V => 10, W => 12, X => 14, Y => 16, Z => 18,
);
sub new {
my $proto = shift;
my $type = shift;
my $class = ref($proto) || $proto;
my $self = bless({}, $class);
$self->{type} = lc($type);
return $self;
} # new()
sub is_valid {
my ($self,$number) = @_;
if ($number =~ /^([-0-9a-z]+)(\d)$/i) {
return $2 == $self->_compute_checkdigits($1);
}
return undef;
} # is_valid()
sub complete {
my ($self,$number) = @_;
if ($number =~ /^([-0-9a-z]+)$/i
and (my $cd = $self->_compute_checkdigits($1)) ne '') {
return $1 . $cd;
}
return undef;
} # complete()
sub basenumber {
my ($self,$number) = @_;
if ($number =~ /^([-0-9a-z]+)(\d)$/i) {
return $1 if ($2 == $self->_compute_checkdigits($1));
}
return undef;
} # basenumber()
sub checkdigit {
my ($self,$number) = @_;
if ($number =~ /^([-0-9a-z]+)(\d)$/i) {
return $2 if ($2 == $self->_compute_checkdigits($1));
}
return undef;
} # checkdigit()
sub _compute_checkdigits {
my $self = shift;
my $number = shift;
$number =~ s/-//g;
my @digits = split(//,$number);
my $len = scalar(@digits) + 1;
my $sum = 0;
for (my $i = 0; $i <= $#digits; $i++) {
$sum += $weight[$i] * $table_to{uc($digits[$i])};
}
$sum %= 11;
return ($sum == 0) ? 1 : ($sum == 1) ? 0 : 11 - $sum;
} # _compute_checkdigit()
# Preloaded methods go here.
1;
__END__
=head1 NAME
CheckDigits::M11_012 - compute check digits for Bundeswehrpersonenkennnummer (DE)
=head1 SYNOPSIS
use Algorithm::CheckDigits;
$bwpk = CheckDigits('bwpk_de');
if ($bwpk->is_valid('151058-D-20711')) {
# do something
}
$cn = $bwpk->complete('151058-D-2071');
# $cn = '151058-D-20711'
$cd = $bwpk->checkdigit('151058-D-20711');
# $cd = '1'
$bn = $bwpk->basenumber('151058-D-20711');
# $bn = '151058-D-2071';
=head1 DESCRIPTION
=head2 ALGORITHM
=over 4
=item 1
Beginning left all digits are weighted 2,3,4,5,6,7,1,6,7,2,3. Letters
are replaced according to the following table:
my %table_to = (
A => 12, B => 14, C => 16, D => 18, E => 20,
F => 22, G => 24, H => 26, I => 28, J => 6,
K => 8, L => 10, M => 12, N => 14, O => 16,
P => 18, Q => 20, R => 22, S => 4, T => 6,
U => 8, V => 10, W => 12, X => 14, Y => 16,
Z => 18,
);
=item 2
The weighted digits are added.
=item 3
The sum from step 2 is taken modulo 11.
=item 4
The checksum is 11 minus the sum from step 3.
If the difference is 10, the checkdigit is 0.
If the difference is 11, the checkdigit is 1.
=back
=head2 METHODS
=over 4
=item is_valid($number)
Returns true only if C<$number> consists solely of numbers and hyphens
and the two digits in the middle
are valid check digits according to the algorithm given above.
Returns false otherwise,
=item complete($number)
The check digit for C<$number> is computed and inserted into the
middle of C<$number>.
Returns the complete number with check digit or '' if C<$number>
does not consist solely of digits, hyphens and spaces.
=item basenumber($number)
Returns the basenumber of C<$number> if C<$number> has a valid check
digit.
Return '' otherwise.
=item checkdigit($number)
Returns the check digits of C<$number> if C<$number> has valid check
digits.
Return '' otherwise.
=back
=head2 EXPORT
None by default.
=head1 AUTHOR
Mathias Weidner, E<lt>mathias@weidner.in-bad-schmiedeberg.deE<gt>
=head1 SEE ALSO
L<perl>,
L<CheckDigits>,
F<www.pruefziffernberechnung.de>,
=cut
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