package pronounce_number;

# Package Stuff.
use Exporter;
@ISA=(Exporter);
@EXPORT=('pronounce_number', 'set_format');

my @v = ( [ '', 'one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine', 'ten', 'eleven',
	'twelve', 'thirteen', 'fourteen', 'fifteen', 'sixteen', 'seventeen', 'eighteen', 'nineteen'],
	[ '', 'ten', 'twenty', 'thirty', 'forty', 'fifty', 'sixty', 'seventy', 'eighty', 'ninety' ]);
my @m = ('', ' million', ' billion', ' trillion', ' quadrillion', ' quintillion');
my @g = ('', ' thousand');
my @h=('',' hundred');
my @and=('',' and ');

my %format = ( space=>'', point=>'point');

sub set_format {
	%format = @_;
}

sub integer_grammar($) {
	my ($u,$t,$h) = reverse(split//,$_[0]);
	return $v[0]->[$h].$h[!!$h].$and[!!($h&&($t||$u))].$v[!(1==$t&&($u+=10)&&($t=0))]->[$t].$format{'space'}.$v[0]->[$u];
}

sub float_grammar($) {
	$_[0]=~s/(\d)/$v[0]->[$1] /geo;
	return $_[0];
}

sub magnitude_grammar {
	return $g[(($_[0]-1)/3)%2].$m[$_[0]/6 * !!($_[0]%6)].' ';
}

sub pronounce_integer($) {

	$_=join("",(reverse(split//,$_[0])));
	my ($i,$n,@l)=(0,"",());
	foreach $n(/(\d{1,3})/g) {
		$n=join("",(reverse(split//,$n)));
		$i+=length($n);
		push @l,($n && defined(@l))?magnitude_grammar($i):"",integer_grammar($n);
	}
	return join('',reverse(@l));
}

sub pronounce_float($) {
	my @n=split/\./,$_[0];
	return pronounce_integer($n[0])." $format{'point'} ".float_grammar($n[1]);
}

sub pronounce_ip($) {
	return join(" $format{'point'} ",map{pronounce_integer($_)}(split/\./,$_[0]));
}

my @process_array=(\&pronounce_integer,\&pronounce_float,\&pronounce_ip);

sub pronounce_number($) {
	my $string = $_[0];
	$string =~ s/,//g;
	$_ = ($string =~ s/\./\./g);
	return &{$process_array[($_<=$#process_array)?$_:2]}($string)
}