package SlackBuild::Registry::Version;
use strict;
use warnings;
use Carp;
use SlackBuild::Base qw(major minor patch tail string:ro);

sub new {
    my $class = shift;
    my $self = bless {}, $class;
    if (my $s = shift) {
	croak "too many arguments" if @_;
	$self->parse($s);
    }
    return $self;
}

sub major_number { shift->major || 0 };
sub minor_number { shift->minor || 0 };
sub patch_number { shift->patch || 0 };
sub tail_string { shift->tail || '' };

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

    $self->{string} = $str;
    delete $self->{major};
    delete $self->{minor};
    delete $self->{patch};
    delete $self->{tail};
    
    if ($str =~ s/^(\d+)(.*)/$2/) {
	$self->major($1);
	if ($str =~ s/^\.(\d+)(.*)/$2/) {
	    $self->minor($1);
	    if ($str =~ s/^\.(\d+)(.*)/$2/) {
		$self->patch($1);
	    }
	}
    }
    $self->tail($str);
}

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

    $other = __PACKAGE__->new($other) unless ref($other);
    
    foreach my $part (map { "${_}_number" } qw(major minor patch)) {
	if (my $d = $self->${\$part} <=> $other->${\$part}) {
	    return $d;
	}
    }
    return $self->tail_string cmp $other->tail_string;
}

use overload
    '""' => sub { shift->string },
    'cmp' => sub {
	my ($self, $other, $swap) = @_;
	my $res = $self->cmp($other);
	return $swap ? -$res : $res;
    },
    '<=>' => sub {
	my ($self, $other, $swap) = @_;
	my $res = $self->cmp($other);
	return $swap ? -$res : $res;
    },
    '==' => sub {
	my ($self, $other) = @_;
	my $res = $self->cmp($other) == 0;
    },
    '!=' => sub {
	my ($self, $other) = @_;
	my $res = $self->cmp($other) != 0;
    },
    '<' => sub {
	my ($self, $other, $swap) = @_;
	my $res = $self->cmp($other) < 0;
	return $swap ? !$res : $res;
    },
    '<=' => sub {
	my ($self, $other, $swap) = @_;
	my $res = $self->cmp($other) <= 0;
	return $swap ? !$res : $res;
    },
    '>' => sub {
	my ($self, $other, $swap) = @_;
	my $res = $self->cmp($other) > 0;
	return $swap ? !$res : $res;
    },
    '>=' => sub {
	my ($self, $other, $swap) = @_;
	my $res = $self->cmp($other) >= 0;
	return $swap ? !$res : $res;
    };


1;