# GUI for _LF_aligner_2012_01_16.pl


package MyGuiStdin;
our @ISA = qw[ Thread::Queue ];

sub TIEHANDLE { bless $_[1], $_[0]; }
sub READLINE { $_[0]->dequeue(); }

package MyGuiStdout;
our @ISA = qw[ Thread::Queue ];

sub TIEHANDLE { bless $_[1], $_[0]; }
sub PRINT  { $_[0]->enqueue( join ' ', @_[ 1 .. $#_ ] ); }
sub PRINTF { $_[0]->enqueue( sprintf $_[1], @_[ 2 .. $#_ ] ); }

package MyGui;
use strict;
use warnings;
use threads;
use Thread::Queue;

my $Qin  = new Thread::Queue;
my $Qout = new Thread::Queue;

tie *STDIN,  'MyGuiStdin',  $Qin;
tie *STDOUT, 'MyGuiStdout', $Qout;

# everything up to this point is pure black magic

sub gui {
	require Tk; #OK
	require Tk::DialogBox; #OK

	my $mw = Tk::MainWindow->new; #OK
	my $lb = $mw->Listbox( -width => 80, -height => 24 )->pack;

	my $ef = $mw->Entry( -width => 70, -takefocus => 1 )->pack( -side => 'left' ); #OK
	my $enter = sub {	# I guess this is to avoid the "will not stay shared" error due to nested subs
		$Qin->enqueue( $ef->get ); # pass the entry field's content to the STDIN of the .pl 
		$ef->delete(0, 'end' );	# delete all the text from the entry field
		1;	# what does this do?
	};
	my $do = $mw->Button( -text => 'go', -command => $enter)->pack( -after => $ef );	#OK
	$mw->bind( '<Return>', $enter );	#Ok
	$ef->focus( -force );	#OK

	my $doStdout = sub {
		if( $Qout->pending ) {	# no clue
			my $output = $Qout->dequeue;	# read STDOUT of .pl into var
			$lb->insert( 'end', $output ) ;	# print STDOUT of .pl in listbox 
			$lb->see( 'end' );				# What's this?

				if( $output eq 'whatever' ) {
				# actual Tk code 
			}


		}
	};

	$mw->repeat( 500, $doStdout ); # execute $doStdout once every 500 millisec...? but why mw->

	Tk::MainLoop(); #OK
}

1;