#!/usr/bin/perl

use warnings;
use strict;
use lib '.';
use Tools;  # local == Data::IEEE754::Tools

use constant {
    POS_ZERO        => '0'.'00000000000'.'0000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000',
    POS_DENORM_1ST  => '0'.'00000000000'.'0000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000001',
    POS_DENORM_LST  => '0'.'00000000000'.'1111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111',
    POS_NORM_1ST    => '0'.'00000000001'.'0000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000',
    POS_NORM_LST    => '0'.'11111111110'.'1111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111',
    POS_INF         => '0'.'11111111111'.'0000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000',
    POS_SNAN_1ST    => '0'.'11111111111'.'0000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000001',
    POS_SNAN_LST    => '0'.'11111111111'.'0111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111',
    POS_IND         => '0'.'11111111111'.'1000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000',
    POS_QNAN_1ST    => '0'.'11111111111'.'1000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000001',
    POS_QNAN_LST    => '0'.'11111111111'.'1111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111',
    NEG_ZERO        => '1'.'00000000000'.'0000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000',
    NEG_DENORM_1ST  => '1'.'00000000000'.'0000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000001',
    NEG_DENORM_LST  => '1'.'00000000000'.'1111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111',
    NEG_NORM_1ST    => '1'.'00000000001'.'0000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000',
    NEG_NORM_LST    => '1'.'11111111110'.'1111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111',
    NEG_INF         => '1'.'11111111111'.'0000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000',
    NEG_SNAN_1ST    => '1'.'11111111111'.'0000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000001',
    NEG_SNAN_LST    => '1'.'11111111111'.'0111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111',
    NEG_IND         => '1'.'11111111111'.'1000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000',
    NEG_QNAN_1ST    => '1'.'11111111111'.'1000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000000'.'00000001',
    NEG_QNAN_LST    => '1'.'11111111111'.'1111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111'.'11111111',  
};
my @list = (
    POS_ZERO, POS_DENORM_1ST, POS_DENORM_LST, POS_NORM_1ST, POS_NORM_LST,
    POS_INF, POS_SNAN_1ST, POS_SNAN_LST,
    POS_IND, POS_QNAN_1ST, POS_QNAN_LST,
    NEG_ZERO, NEG_DENORM_1ST, NEG_DENORM_LST, NEG_NORM_1ST, NEG_NORM_LST,
    NEG_INF, NEG_SNAN_1ST, NEG_SNAN_LST,
    NEG_IND, NEG_QNAN_1ST, NEG_QNAN_LST
);

sub bitsToDouble{ unpack 'd',  pack 'b64', scalar reverse $_[0] }
sub bitsToInts{   reverse unpack 'VV', pack 'b64', scalar reverse $_[0] }
sub doubleToBits{ scalar reverse unpack 'b64', pack 'd', $_[0] }
printf "%23.16g : %08x%08x >=there-and-back-again=> %08x%08x\n", 
    bitsToDouble( $_ ), bitsToInts( $_ ), 
    bitsToInts( doubleToBits( bitsToDouble( $_ ) ) )
    for @list;

print "\n";

use Test::More tests => 22;
is( doubleToBits( bitsToDouble( $_ ) ) , $_ , "bitsToDouble(doubleToBits($_))" ) for @list;