use Tk;
use Tk::BrowseEntry;
use Tk::Dialog;
my $note = "This is the 'Subject' area. Usually, you will paste
something in here.
Below is some code that fires when you click the 
'stringilize' button. It modifies the text in this
area. Change it to whatever you like.
Errors in your code (if there are any), will be 
inserted here.
";
my $def_code =<<EOC;
my \@subject_lines = split(/\\n/, \$subject_text->get('1.0','end') );
for (\@subject_lines) {
   # Do something, e.g.
   # tr/a-z/A-Z/;
}
\$subject_text->delete('1.0', 'end');
\$subject_text->insert( 'end', join("\\n", \@subject_lines) );
EOC
my $snippets_dir = 'snippets';
my $mainw = MainWindow->new(-title=>'Stringilizer');
my $tags;
my $dia = $mainw->Dialog(
	-title =>'Tag snippet',
	-default_button=>'Save'
);
$dia->add(
	'LabEntry', 
	-textvariable=>\$tags, 
	-label=>'Enter tags to save snippet' 
)->
pack(-side => 'left')->
configure(-relief=>'groove');
$dia->protocol("WM_DELETE_WINDOW" => sub {} );
my $frame1 = $mainw->Frame->pack(
	-side => 'top', 
	-fill => 'x'
	);	
$frame1->Button(
	-text => "exit",
	-command => sub { $mainw->destroy; } )->
	pack(-side => 'left')->
	configure(-relief=>'groove');
$frame1->Button(-text => "stringilize", 
	-command => \&stringilize_exec )->
	pack(-side => 'left')->
	configure(-relief=>'groove');
$frame1->Button(-text => "save", 
	-command => \&save_snippet )->
	pack(-side => 'left')->
	configure(-relief=>'groove');
$code_text = $mainw->Scrolled("Text")->
	pack(-side => 'bottom', -fill => 'both', -expand => 1);
$subject_text = $mainw->Scrolled("Text")->
	pack(-side => 'bottom', -fill => 'both', -expand => 1);	  	
$subject_text->configure(-height => 12, -scrollbars=>'se');	  	
$code_text->configure(-height => 18, -scrollbars=>'se');
$subject_text->insert('end', $note);
$code_text->insert('end', $def_code);
my $snippet;
my $be = $frame1->BrowseEntry(
	-label=>'snippets', 
	-browsecmd=> \&load_snippet,
	-variable=> \$snippet
);
load_snippet_tags();
$be->pack(
	-side => 'left')->configure(
	-relief=>'groove');
MainLoop;
sub stringilize_exec {
	# Put the code area text into variable	
	my $code = $code_text->get("1.0", 'end');
	eval($code);
	# Report error
	if ($@) { $subject_text->insert('1.0', "ERROR: $@\n"); }
}
sub load_snippet_tags {
	$be->delete('0', 'end');
	if (!-e $snippets_dir and !-d $snippets_dir) {
		mkdir $snippets_dir;
		return;
	}
	opendir(DIR, $snippets_dir) || die "$!";
	my @files = 
		grep { /txt$/i && -f "$snippets_dir\/$_" } readdir(DIR);
	closedir(DIR);
	for (@files) {
		my $f = $_;
		$f =~ s/\.txt$//;	
		$be->insert('end', $f);
	}
}
sub load_snippet {
	my $file = $snippet . '.txt';
	open(F, "$snippets_dir\/$file") or die "$! $snippets_dir\/$file";
	my $s;
	while(<F>){ $s .= $_ }
	close(F);
	$code_text->delete('1.0', 'end');
	$code_text->insert('end', $s);
}
sub save_snippet {
	my $ans = $dia->Show;
	if ($tags ne '') {
		$tags =~ s/\s/_/g;
		$tags =~ s/\W//g;
		$tags =~ s/_/ /g;
		open(F, ">$snippets_dir\/$tags\.txt") or die "$!";
		print F $code_text->get('1.0','end');
		close(F);
		load_snippet_tags();
		undef($tags);
	}
}