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package PDF::Builder::Resource::XObject::Form::BarCode::ean13;
use base 'PDF::Builder::Resource::XObject::Form::BarCode';
use strict;
use warnings;
our $VERSION = '3.028'; # VERSION
our $LAST_UPDATE = '3.027'; # manually update whenever code is changed
=head1 NAME
PDF::Builder::Resource::XObject::Form::BarCode::ean13 - Specific information for EAN-13 bar codes
Inherits from L<PDF::Builder::Resource::XObject::Form::BarCode>
=head1 METHODS
=head2 new
PDF::Builder::Resource::XObject::Form::BarCode::ean13->new()
=over
Create an EAN-13 bar code object. Note that it is invoked from the Builder.pm
level method!
=back
=cut
sub new {
my ($class, $pdf, %options) = @_;
# copy dashed option names to preferred undashed names
if (defined $options{'-code'} && !defined $options{'code'}) { $options{'code'} = delete($options{'-code'}); }
my $self = $class->SUPER::new($pdf, %options);
my @bars = $self->encode($options{'code'});
$self->drawbar([@bars], $options{'caption'});
return $self;
}
my @ean_code_odd = qw(3211 2221 2122 1411 1132 1231 1114 1312 1213 3112);
my @ean_code_even = qw(1123 1222 2212 1141 2311 1321 4111 2131 3121 2113);
my @parity = qw(OOOOOO OOEOEE OOEEOE OOEEEO OEOOEE OEEOOE OEEEOO OEOEOE OEOEEO OEEOEO);
sub encode {
my ($self, $string) = @_;
my @digits = split(//, $string);
# The first digit determines the even/odd pattern of the next six
# digits, and is printed to the left of the barcode
my $first = shift(@digits);
my @bars = (['07', $first]);
# Start Guard
push @bars, 'a1a';
# Digits 2-7
foreach my $i (0 .. 5) {
my $digit = shift(@digits);
if (substr($parity[$first], $i, 1) eq 'O') {
push @bars, [$ean_code_odd[$digit], $digit];
} else {
push @bars, [$ean_code_even[$digit], $digit];
}
}
# Center Guard
push @bars, '1a1a1';
# Digits 8-13
for (0..5) {
my $digit = shift @digits;
push @bars, [$ean_code_odd[$digit], $digit];
}
# Right Guard
push @bars, 'a1a';
return @bars;
}
sub calculate_check_digit {
my ($self, $string) = @_;
my @digits = split(//, $string);
my $weight = 1;
my $checksum = 0;
foreach my $i (0..11) {
$checksum += $digits[$i] * $weight;
$weight = $weight == 1? 3: 1;
}
$checksum = $checksum % 10;
return 0 unless $checksum;
return 10 - $checksum;
}
1;
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