package Klax;

sub new {

    my $class = shift;
    my $self = {@_};
    bless ($self, $class);
    $self->init ();
    return $self;

}

1;
######################################################################

package Klax::Game;
use base 'Klax';

sub init {
    
    my $self = shift;
    
    my $board = $self->{'board'} =
	new Klax::Board ("width" => $self->{"width"},
			 "height" => $self->{"height"});

    my $stack = $self->{'stack'} = 
	new Klax::Stack ("size" => $self->{"ssize"},
			 "posmax" => $self->{"width"},
			 "pos" => 0);

    my $grid = $self->{'grid'} = 
	new Klax::Grid ("width" => $self->{"width"},
			"height" => $self->{"depth"});

    $stack->rand;
    $board->rand;

    return $self;

}

sub popdown {

    my $self = shift;
    my $val = $self->{"stack"}->pop;

    if (length ($val) and
	($self->{"board"}->push ($val, $self->{"stack"}->{"pos"}))) {
	return $self;
    }
    
    return undef;
	
}

sub pos {

    my $self = shift;
    my $col = shift;

    if ($self->{"stack"}->pos ($col)) {
	return $self;
    }
    
    return undef;

}
######################################################################
package Klax::Board;
use base 'Klax';

sub init {

    my $self = shift;
    my $data = $self->{"data"} = [];

    for (1..$self->{"width"}) {
	my $col = [];
	push (@{$col}, ' ') 
	    for (1..$self->{"height"});
	push (@{$data}, $col);
    }

    return $self;
}

sub rand {

    my $board = shift;

    for (1..(int (rand ($board->{"width"} * $board->{"height"})))) {
	$board->push (int (rand (8)), int (rand (5)));
    }
    
    return $board;

}

sub push {
    
    my $self = shift;
    my $num = shift;
    my $col = shift;

    return undef 
	unless (($col >= 0) and ($col < $self->{"width"}));

    my $cdat = $self->{"data"}->[$col];
    my $row = 0;
    
    $row++ 
	while (($row < $self->{"height"}) and ($cdat->[$row] ne ' '));
    
    return undef
	if ($row == $self->{"height"});
    
    $cdat->[$row] = $num;

    return $self;
}
######################################################################
package Klax::Stack;
use base 'Klax';

sub init {

    my $self = shift;
    my $data = $self->{"data"} = [];
    
    return $self;
}

sub rand {
    
    my $stack = shift;

    for (1..(int (rand ($stack->{"size"} + 1)))) {
	$stack->push (int (rand (8)));
    }
	
    $stack->pos (int (rand ($stack->{"posmax"})));
    
    return ($stack);
}

sub push {

    my $self = shift;
    my $num = shift;
    
    if (($#{$self->{"data"}} + 1) < $self->{"size"}) {
	push (@{$self->{"data"}}, $num);
	return $self;
    } else {
	return undef;
    }
    
}

sub pop {
    
    my $self = shift;
    
    return shift (@{$self->{"data"}});

}

sub pos {

    my $self = shift;
    my $pos = shift;
    $self->{"pos"} = $pos;
    return $self;

}
       
######################################################################
package Klax::Grid;
use base 'Klax';

sub init {
    
    my $self = shift;
    my $data = $self->{"data"} = [];
    
    for (1..$self->{"width"}) {
	my $col = [];
	push (@{$col}, ' ')
	    for (1..$self->{"height"});
	push (@{$data}, $col);
    }

    return $self;
}