#!/usr/bin/env perl

use strict;
use warnings;
use autodie qw{:all};

use Time::HiRes;
use Tk;
use Tk::LabFrame;

print 'Hit enter when ready to make selection: ';
(undef) = scalar <>;

my $no_selection_msg = 'No item selected';
my $filename = join '.' => Time::HiRes::time, $$, 'tmp';
open my $pre_fork_fh, ">", $filename;
print $pre_fork_fh $no_selection_msg;
close $pre_fork_fh;

my $pid = fork;

if ($pid == 0) {
    my $mw = MainWindow->new;
    $mw->geometry('200x300+50+50');

    my $app_F = $mw->Frame();
    $app_F->pack(-padx => 10, -pady => 10, -fill => 'both', -expand => 1);

    my $command_LF = $app_F->LabFrame(
        -label => 'Commands',
        -labelside => 'acrosstop'
    )->pack(-side => 'bottom', -fill => 'x', -expand => 0);

    my $selections_LF = $app_F->LabFrame(
        -label => 'Selections',
        -labelside => 'acrosstop'
    )->pack(-side => 'top', -fill => 'both', -expand => 1);

    my $selections_Lb = $selections_LF->Scrolled(Listbox =>
        -scrollbars => 'osoe',
        -selectmode => 'single'
    )->pack(-padx => 5, -pady => 5, -fill => 'both', -expand => 1);

    $selections_Lb->insert(end => map { "$_ selected" } 'A' .. 'Z');

    my $save_B = $command_LF->Button(
        -text => 'Save Selection',
        -command => sub {
            my $selection_index = $selections_Lb->curselection();
            my $selection = length $selection_index
                          ? $selections_Lb->get($selection_index)
                          : $no_selection_msg;
            open my $child_fork_fh, ">", $filename;
            print $child_fork_fh $selection;
            close $child_fork_fh;
            exit;
        }
    )->pack(-padx => 5, -pady => 5);

    MainLoop;

    exit;
}

waitpid $pid => 0;

open my $post_fork_fh, "<", $filename;
my $selection = <$post_fork_fh>;
close $post_fork_fh;
unlink $filename;

print "Selection made: $selection\n";