File Coverage

blib/lib/Net/OnlineCode/Encoder.pm

Criterion	Covered	Total	%
statement	15	27	55.5
branch	0	4	0.0
condition			n/a
subroutine	5	7	71.4
pod	2	2	100.0
total	22	40	55.0

package Net::OnlineCode::Encoder;

use strict;
use warnings;

use Carp;

use Net::OnlineCode;

use vars qw(@ISA @EXPORT_OK %EXPORT_TAGS $VERSION);

require Exporter;

# Inherit from base class
@ISA = qw(Net::OnlineCode Exporter);
@EXPORT_OK = qw();

$VERSION = '0.02';

sub new {

  my $class = shift;

  my %opts = (
	      # include any encoder-specific arguments here
	      initial_rng      => undef,
	      @_
	     );

  my $self = $class->SUPER::new(@_);

  print "encoder mblocks: $self->{mblocks}\n";

  croak "Failed to create superclass\n" unless ref($self);

  $self->auxiliary_mapping($opts{initial_rng});

  # delete unwanted mblocks elements from aux_mapping
  #splice $self->{aux_mapping}, 0, $self->{mblocks};

  return $self;
}


# to create check blocks, call the parent's checkblock_mapping method
# to find the mapping, then optionally expand any auxiliary block
# numbers with the message blocks they're composed of.

sub create_check_block {

  my ($self, $rng) = @_;

  # already tested by parent method:
  # croak "rng parameter must be an object ref" unless ref($rng);

  my $xor_list  = $self->checkblock_mapping($rng);

  # Optionally replace auxiliary indices with a list of message
  # indices.  Message blocks may appear multiple times in the
  # expansion: once for an explicit mention in the checkblock, and
  # potentially several times in the expansion of auxiliary blocks. We
  # eliminate any message blocks that appear an even number of times
  # in the expansion since xoring by the same thing twice is a null
  # operation.
  #
  # Note that although we use the same option name (expand_aux) in the
  # encoder and decoder, the implementations are different. Here we
  # expand aux blocks indices into message indexes, whereas in the
  # decoder, we expand them into check block indices.

  if ($self->{expand_aux}) {
    return [ $self->blklist_to_msglist(@$xor_list) ];
  } else {
    return $xor_list;
  }
}

1;


__END__