use POE qw/Wheel::ReadLine/;

BEGIN {

package R2::Thread;

use Inline Guile => <<END;
  (define call/cc call-with-current-continuation)
  (define postback (lambda (p)
    (call/cc (lambda (k) ( (throw 'postback k p ))))))
  (define wrap-catcher (lambda (key k p)
    (list k p)))
  (define catchwrap (lambda (proc)
    (catch 'postback (lambda () (proc) ) wrap-catcher )))
  (define string-write
    (lambda (obj) (call-with-output-string
      (lambda (port) (write obj port)))))
  (define repl (lambda () 
    (do ((command-string #f) (command-results #f)) (#f)
      (set! command-string (postback command-results))
      (set! command-results (string-write (eval-string command-string))))))
  (define postreturn (lambda (kont arg) (kont arg) ))
END

sub new {
	my $new = bless({}, 'R2::Thread');
	my $l = catchwrap(Guile::lookup('repl'));
	$new->{kont} = $l->[0];
	return $new;
}

sub do {
	my ($self, $code) = @_;
	my $string = new Guile::SCM string => $code;
	my $l = postreturn($self->{kont}, $string);
	$self->{kont} = $l->[0];
	return $l->[1];
}

} ####### END BEGIN BLOCK

POE::Session->create(
	inline_states => {
		_start => \&init,
		line => \&input_line } );

sub init {
	$_[HEAP]->{wheel} = POE::Wheel::ReadLine->new( InputEvent => 'line' );
	$_[HEAP]->{prompt} = ':';
	$_[HEAP]->{wheel}->put("Welcome to R2");
	$_[HEAP]->{wheel}->get($_[HEAP]->{prompt});
	$_[HEAP]->{thread} = new R2::Thread;
}

sub input_line {
	my ($heap, $input, $exception) = @_[HEAP, ARG0, ARG1];
	if (defined $input) {
		my $res = $_[HEAP]->{thread}->do("($input)");
		$_[HEAP]->{wheel}->put($res);
	} else {
		print "Argh!\r\n";
		delete $_[HEAP]->{wheel};
		return;
	}
	$_[HEAP]->{wheel}->get($_[HEAP]->{prompt});
}

POE::Kernel->run();

exit;