package Specification
{
    use Moo;

    sub And
    {
        my $self = shift;
        my $spec = shift;
        return AndSpecification->new( left => $self, right => $spec );
    };
    sub Or
    {
        my $self = shift;
        my $spec = shift;
        return OrSpecification->new( left => $self, right => $spec );
    };
    sub Not
    {
        my $self = shift;
        return NotSpecification->new( specification => $self );

    }
}

package AndSpecification
{
    use Moo;
    extends 'Specification';
    #
    has left => ( is => 'ro' );
    has right => ( is => 'ro' );

    sub is_satisfied_by
    {
        my $self = shift;
        my $object = shift;

        return $self->left->is_satisfied_by( $object ) && $self->right->is_satisfied_by( $object );
    }
}
package OrSpecification
{
    use Moo;
    extends 'Specification';

    #
    has left => ( is => 'ro' );
    has right => ( is => 'ro' );
    sub is_satisfied_by
    {
        my $self = shift;
        my $object = shift;

        return $self->left->is_satisfied_by( $object ) || $self->right->is_satisfied_by( $object );
    }
}
package NotSpecification
{
    use Moo;
    extends 'Specification';

    has specification => ( is => 'ro' );

    sub is_satisfied_by
    {
        my $self = shift;
        my $object = shift;
        return !$self->specification->is_satisfied_by( $object );
    }
}

package RAMSpecification
{
    use Moo;
    extends 'Specification';

    sub is_satisfied_by
    {
        my $self = shift;
        my $car = shift;
        return $car->make_id == 7777 ? 1 : 0
    }
}
package MY21Specification
{
    use Moo;
    extends 'Specification';

    sub is_satisfied_by
    {
        my $self = shift;
        my $car = shift;
        return $car->model_year == 2021 ? 1 : 0
    }

}
package isSoldSpecification
{
    use Moo;
    extends 'Specification';

    sub is_satisfied_by
    {
        my $self = shift;
        my $car = shift;
        return $car->is_sold ? 1 : 0;
    }
}

package Car
{
    use Moo;

    has make_id => ( is => 'ro' );
    has model_year => ( is => 'ro' );
    has color => ( is => 'ro' );
    has is_sold => ( is => 'ro' ); #       => (is => 'ro');
}

my $car = Car->new( make_id => 7777, model_year => 2021, color => 'Green', is_sold => 1 );
my $ram_spec = RAMSpecification->new();
my $my21_spec = MY21Specification->new();
my $is_sold = isSoldSpecification->new();

my $spec = $ram_spec->  # Model RAM
    And( $my21_spec )-> # Model Year 2021
    Not( $is_sold );    # is not sold
my $is_valid = $spec->is_satisfied_by( $car );

say STDERR $is_valid ? 'Valid' : 'Not Valid';