#!/usr/bin/perl

use warnings;
use strict;

use Tk;

package MyButton {

    sub new {
        my $classname = shift;
        my $self = {nr => shift};
        return bless($self, $classname);
    }

    sub createButton {
        my $self = shift;
        my $main = shift;
        my $frame = shift;
        $self->{button} = $frame->Button(-text => $self->{nr}, -command => sub { $main->btnClick($self->{nr}) });
        $self->{button}->pack(-side => "left", -pady => 5);
    }
}

package MyWindow {

    sub new {
        my $classname = shift;
        my $self = {};
        return bless($self, $classname);
    }

    sub createWindow {
        my $self = shift;
        $self->{mw} = MainWindow->new(-title => "pdfRename");
        $self->{mw}->optionAdd("*font", "Arial 15 normal");
        $self->{mw}->geometry("+400+256");
        $self->{mw}->bind("<Control-q>" => sub { $self->{mw}->destroy()});
        my ($i, $u, $mb, $frame);
        my $nr = 1;
        for $i (0 .. 3) {
            $frame = $self->{mw}->Frame();
            for $u (0 .. 7) {
                if ($i == 3 && $u == 7) {
                    next;
                }
                $mb = MyButton->new($nr);
                $mb->createButton($self, $frame);
                $nr++;
            }
            $frame->pack();
        }
        $self->{mw}->MainLoop();
    }

    sub btnClick {
        my $self = shift;
        my $nr = shift;
        my $a = $self->getPdfFilename();
        print "$a\t\t$nr\n";
    }

    sub getPdfFilename {
        my $self = shift;
        my $a = `ps x | grep pdf`;
        my @b = split(/\n/, $a);
        my $i;
        my @c;
        for $i (@b) {
            if ($i =~ /grep/) {
                next;
            }
            push(@c, $i);
        }
        if ($#c < 0) {
            print "\nWarning: No pdf-process found.\n";
            return "None";
        }
        $a = $c[0];
        chomp($a);
        @b = split(/ /, $a);
        for $i (@b) {
            if ($i =~ /\.pdf/) {
                return $i;
            }
        }
        print "\nWarning: No pdf-filename found.\n";
        return "None";
    }
}

my $app = MyWindow->new();
$app->createWindow();