#
# $Id: Drag.pm,v 4.6 1999/06/14 05:13:13 kono Exp $
#

package CardPlay::Drag;

use strict;

use vars qw($VERSION @ISA @EXPORT @EXPORT_OK
);

require Exporter;
require AutoLoader;

@ISA = qw(Exporter AutoLoader );

@EXPORT = qw( );

$VERSION = "0.2";

use Tk;
use Carp;

# bounding box for dragging
#
# (x,y)-(x1,y1) / $object

# class method

sub new {
    my ($types) = shift;
    my $self;

    %$self = @_;
    $self->{'-drag_object'}=[];
    bless $self;
}

# instance method

sub add_drag {
    my $self = shift;
    my ($object) = @_;
    return if (!$object->can('bbox'));

    $self->delete_drag($object);
    push (@{$self->{'-drag_object'}},$object);
}

sub delete_drag {
    my $self = shift;
    my ($object) = @_;
    for( my $i=0;$i <= $#{$self->{'-drag_object'}};$i++ ) {
	next if ($self->{'-drag_object'}->[$i] ne $object);
	splice(@{$self->{'-drag_object'}},$i,1);
    }
}

sub check_drag {
    my $self = shift;
    my ($x,$y) = @_;
    my ($x0,$y0,$x1,$y1);
    my ($i);

    foreach $i ( @{$self->{'-drag_object'}} ) {
	($x0,$y0,$x1,$y1) = $i->bbox();
	next if ($x < $x0 || $x1 < $x);
	next if ($y < $y0 || $y1 < $y);
	return $i;
    }
    return undef;
}

1;
# end
