package Algorithm::CheckDigits::M10_010;
use 5.006;
use strict;
use warnings;
use integer;
use version; our $VERSION = 'v1.3.2';
our @ISA = qw(Algorithm::CheckDigits);
my @items = ( 0,9,4,6,8,2,7,1,3,5 );
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 =~ /^(\d\d-?\d{8})-?(\d)$/) {
return $2 == $self->_compute_checkdigit($1);
}
return ''
} # is_valid()
sub complete {
my ($self,$number) = @_;
if ($number =~ /^\d\d-?\d{8}-?$/) {
return $number . $self->_compute_checkdigit($number);
}
return '';
} # complete()
sub basenumber {
my ($self,$number) = @_;
if ($number =~ /^(\d\d-?\d{8}-?)(\d)$/) {
return $1 if ($2 == $self->_compute_checkdigit($1));
}
return '';
} # basenumber()
sub checkdigit {
my ($self,$number) = @_;
if ($number =~ /^(\d\d-?\d{8})-?(\d)$/) {
return $2 if ($2 == $self->_compute_checkdigit($1));
}
return '';
} # checkdigit()
sub _compute_checkdigit {
my $self = shift;
my $number = shift;
if ($number =~ /^\d\d-?\d{8}-?$/) {
$number =~ s/-//g;
my @digits = split(//,$number);
my $sum = 0;
my $cf = 0;
for (my $i = 0; $i <= $#digits; $i++) {
$cf = $items[($digits[$i] + $cf) % 10];
}
return (10 - $cf) % 10;
}
return -1;
} # _compute_checkdigit()
# Preloaded methods go here.
1;
__END__
=head1 NAME
CheckDigits::M10_010 - compute check digits for Postscheckkonti (CH)
=head1 SYNOPSIS
use Algorithm::CheckDigits;
$pck = CheckDigits('postcheckkonti');
if ($pck->is_valid('85-12345678-7')) {
# do something
}
$cn = $pck->complete('85-12345678');
# $cn = '85-12345678-7'
$cd = $pck->checkdigit('85-12345678-7');
# $cd = '7'
$bn = $pck->basenumber('85-12345678-7');
# $bn = '85-12345678'
=head1 DESCRIPTION
=head2 ALGORITHM
=over 4
=item 1
The sequence of digits is processed left to right. For the first digit
we assume a carry forward of 0.
=item 2
For each digit d(i) the carry forward cf(i) is the digit at the
the position p in the sequence ( 0, 9, 4, 6, 8, 2, 7, 1, 3, 5 ), where
p is (d(i) + cf(i-1)) modulo 10.
=item 3
The check digit is the difference of the sum from step 3 to the next
multiple of 10.
=back
=head2 METHODS
=over 4
=item is_valid($number)
Returns true only if C<$number> consists solely of numbers and the last digit
is a valid check digit according to the algorithm given above.
Returns false otherwise,
=item complete($number)
The check digit for C<$number> is computed and concatenated to the end
of C<$number>.
Returns the complete number with check digit or '' if C<$number>
does not consist solely of digits and spaces.
=item basenumber($number)
Returns the basenumber of C<$number> if C<$number> has a valid check
digit.
Return '' otherwise.
=item checkdigit($number)
Returns the checkdigit of C<$number> if C<$number> has a valid check
digit.
Return '' otherwise.
=back
=head2 EXPORT
None by default.
=head1 AUTHOR
Mathias Weidner, C<< <mamawe@cpan.org> >>
=head1 SEE ALSO
L<perl>,
L<CheckDigits>,
F<www.pruefziffernberechnung.de>.
=cut