File Coverage

blib/lib/Math/RNG/Microsoft/FCPro.pm

Criterion	Covered	Total	%
statement	46	50	92.0
branch	8	12	66.6
condition			n/a
subroutine	13	14	92.8
pod	4	4	100.0
total	71	80	88.7

package Math::RNG::Microsoft::FCPro;
$Math::RNG::Microsoft::FCPro::VERSION = '0.2.0';
use 5.014;
use strict;
use warnings;
use integer;
use bigint;


my $MAX_SEED = ( ( 1 << ( 31 + 2 ) ) - 1 );    # 33 bits

sub new
{
    my $class = shift;

    my $self = bless {}, $class;

    $self->_init(@_);

    return $self;
}

sub _seed
{
    my $self = shift;

    if (@_)
    {
        $self->{_seed} = shift;
    }

    return $self->{_seed};
}

sub _seedx
{
    my $self = shift;

    if (@_)
    {
        $self->{_seedx} = shift;
    }

    return $self->{_seedx};
}

my $X = hex("0x100000000");

sub _init
{
    my ( $self, %args ) = @_;

    my $seed = $self->_seed( $args{seed} );
    $self->_seedx( ( $seed < $X ) ? $seed : ( $seed - $X ) );
    return;
}

sub rand
{
    my ( $self, ) = @_;

    if ( $self->_seed < $X )
    {
        my $ret = $self->_rando();
        return ( ( $self->_seed < 0x80000000 ) ? $ret : ( $ret | 0x8000 ) );
    }
    else
    {
        return $self->_randp() + 1;
    }
}

sub _rando
{
    my $self = shift;
    $self->_seedx( ( $self->_seedx() * 214013 + 2531011 ) & $MAX_SEED );
    return ( ( $self->_seedx >> 16 ) & 0x7fff );
}

sub _randp
{
    my $self = shift;
    $self->_seedx( ( $self->_seedx() * 214013 + 2531011 ) & $MAX_SEED );
    return ( ( $self->_seedx >> 16 ) & 0xffff );
}

sub max_rand
{
    my ( $self, $max ) = @_;

    return ( $self->rand() % $max );
}

sub shuffle
{
    my ( $self, $deck ) = @_;

    if (@$deck)
    {
        my $i = @$deck;
        while ( --$i )
        {
            my $j = $self->max_rand( $i + 1 );
            @$deck[ $i, $j ] = @$deck[ $j, $i ];
        }
    }

    return $deck;
}


1;

__END__