#!/usr/bin/perl
use warnings;
use strict;

use Tk;
use Tk::JPEG;
use Tk::Pane;

use File::Spec;

use Data::Dump;

my $glob = $ARGV[0]||'./*.jpg';

my @files;
&build_list($glob);


###########################################################
my $mw = new MainWindow ();
   $mw->geometry("100x50+0+0");

$mw->Button(-text => "nex picture",
                  -command => sub{
                                  &next_pic;
                              }
                  )->pack();

my $phwin = $mw->Toplevel();

# default empty image
#  see http://www.perlmonks.org/?node_id=535837
my $image = $phwin->Photo(-file => '' ) or die $!;
my $photo_label;

#fill mainframe with default screen
setup_pane();

$mw->MainLoop;

################################################################################
sub next_pic {
   my $pic_file = shift @files;
   print "processing [$pic_file]\n";

   $image->blank;
   $image = $phwin->Photo(-file => $pic_file );

   $photo_label->configure(-image => $image );

}
#############################################################
# see http://www.perlmonks.org/?node_id=535837
sub setup_pane{

  my $pane = $phwin->Scrolled('Pane', Name => 'Main Display',
               -width => 1000,
               -height =>1000,
               -background => 'black',
               -scrollbars => 'osoe',
               -sticky => 'n',
              )->pack(-side => "left", -anchor => "n",
                      -fill=>'both',-expand=>1);

  # the global!
  $photo_label = $pane->Label(-image => $image,
                      -background =>'black'
                     )->pack(-side => 'top',
                       -anchor => 'n',
                       -fill => 'both',
                       -expand => 1,
                      );

}
################################################################################
sub build_list{
    my $glob=shift;
    print "received [$glob]\n";
    map {
          push @files,File::Spec->file_name_is_absolute($_) ?
                        $_ : File::Spec->rel2abs($_);
    } glob($glob);
    print "$_\n" for @files;
}