#!/opt/bin/perl

use Cwd ();
use Encode ();

use Gtk2 -init;
use Gtk2::Gdk::Keysyms;

use Gtk2::CV;

use Gtk2::CV::ImageWindow;
use Gtk2::CV::Schnauzer;

BEGIN {
   require Gtk2::CV::Plugin;
   require "$ENV{HOME}/.cvrc" if -r "$ENV{HOME}/.cvrc";
}

use Gtk2::CV::Plugin::NameCluster;
use Gtk2::CV::Plugin::RCluster;

Gtk2::Rc->parse (Gtk2::CV::find_rcfile "gtkrc");

use File::Spec;

my $mainwin;
my $viewer;
my $schnauzer;
my $info;
my $help;

my $schnauzer_idx = 0;

sub new_schnauzer {
   my $s = new Gtk2::CV::Schnauzer;

   $s->signal_connect_after (key_press_event => \&std_keys);
   $s->signal_connect (activate => sub {
      my $label = sprintf "%s (%d)",
                  (File::Spec->splitpath ($_[1]))[2],
                  -s $_[1];
      $info->set_label ($label);
      $viewer->load_image ($_[1]);
   });

   Gtk2::CV::Plugin->call (new_schnauzer => $s);

   $s
}

sub std_keys {
   my $key = $_[1]->keyval;
   my $state = $_[1]->state;

   my $ctrl = $state * "control-mask";

   if ($key == $Gtk2::Gdk::Keysyms{q}) {
      main_quit Gtk2;
   } elsif ($ctrl && $key == $Gtk2::Gdk::Keysyms{v}) {
      my $w = new Gtk2::Window;

      $w->set_title ("CV: Schnauzer");
      $w->add (my $s = new_schnauzer);
      $s->set_dir (File::Spec->curdir);
      $s->set_geometry_hints;
      $w->show_all;

   } elsif ($ctrl && $key == $Gtk2::Gdk::Keysyms{h}) {
      unless ($help) {
         require Gtk2::PodViewer;

         $help = new Gtk2::Window;
         $help->set_title ("CV: Help");
         $help->set_default_size (500, 300);
         $help->signal_connect (delete_event => sub { $help->hide; 1 });

         $help->add (my $sw = new Gtk2::ScrolledWindow);
         $sw->add (my $h = new Gtk2::PodViewer);

         #binmode DATA, ":utf8";
         $h->load_string (do { local $/; <DATA> });
      }

      $help->show_all;
   } else {
      return 0;
   }

   1
}

{
   $viewer = new Gtk2::CV::ImageWindow;

   $viewer->set_title ("CV: Image");

   $viewer->signal_connect (key_press_event => sub {
      &std_keys
         or $schnauzer->signal_emit (key_press_event => $_[1])
   });
   $viewer->signal_connect (delete_event => sub { main_quit Gtk2 });

   $viewer->signal_connect (button3_press_event => sub {
      $mainwin->visible
         ? $mainwin->hide
         : $mainwin->show_all;
      1
   });

   Gtk2::CV::Plugin->call (new_imagewindow => $viewer);

   $schnauzer = new_schnauzer;

   $mainwin = new Gtk2::Window;
   $mainwin->set_title ("CV");
   $mainwin->add (my $vbox = new Gtk2::VBox);
   $mainwin->signal_connect (delete_event => sub { $mainwin->hide; 1 });

   $vbox->add ($schnauzer);
   $vbox->pack_end (my $frame = new Gtk2::Frame, 0, 0, 0);
   $frame->add (my $hbox = new Gtk2::HBox 0, 0);
   $hbox->pack_start ((new Gtk2::Label "Info: "), 0, 0, 0);
   $hbox->pack_end   (my $labelwindow = new Gtk2::EventBox, 1, 1, 0);
   $labelwindow->add ($info = new Gtk2::Label);
   $labelwindow->signal_connect_after (size_request => sub { $_[1]->width (0); 0 });
   $info->set (selectable => 1, xalign => 0, justify => "left");

   $schnauzer->set_geometry_hints;
}

if (@ARGV) {
   @ARGV == 1 && -d $ARGV[0]
      ? $schnauzer->set_dir (Glib::filename_to_unicode shift)
      : $schnauzer->set_paths ([map Glib::filename_to_unicode $_, @ARGV]);
   $schnauzer->show_all;
   $schnauzer->handle_key ($Gtk2::Gdk::Keysyms{space}, []);
} else {
   $schnauzer->set_dir (File::Spec->curdir);
   $mainwin->show_all;
}

$viewer->show_all;

main Gtk2;

__DATA__

=head1 NAME

cv - a fast gtk+ image viewer loosely modeled after XV

=head1 SYNOPSIS

   cv [file...]

=head1 FEATURES

CV is supposed to work similar to the venerable XV image viewer, just
faster. Why faster?

=over 4

=item * optimized directory scanning algorithm

The directory scanning in CV uses some tricks that - on most modern
filesystems - makes it possible to detect filetypes faster than stat()'ing
every file. This makes CV suitable for directories with lots of files
(10000+).

This algorithm is quite unprecise - it doesn't make a difference between
files, device nodes, symlinks and the like, and filetype detection is done
using the file extension only.

On the positive side, it is usually many orders of magnitude faster than
traditional scanning techniques (good for directories with 10000 or
100000+ files).

=item * queuing for all time-consuming background tasks

All tasks, such as unlinking files or generating thumbnails, that can be
done in the background will be done so - no waiting required, even when
changing directories.

=item * use of asynchronous I/O

CV tries to use asynchronous I/O whereever it makes sense, for example
while scanning directories, waiting for stat data, unlinking files or
generating thumbnails. This usually decreases scanning times for large
directories a bit (especially on RAID devices and over NFS) and makes CV
much more interactive.

=item * fast image loading

The time span between the user issuing a command and displaying the new
image should be as small as possible. CV uses optimized (especially
for JPEG) loading functions and sacrifices some quality (e.g no gamma
correction, although this might change) to achieve this speed.

=item * fast thumbnail creation

Thumbnail creation uses both CPU and Disk-I/O. CV interleaves both, so
on modern CPUs, thumbnailing is usually limited by I/O speed. Thumbnail
creation for JPEGs has been specially optimized and can even take
advantage of multiple CPUs.

=item * minimum optical clutter

CV has no menus or other user interface elements that take up a lot of
screen space (or are useful for beginning users). The schnauzer windows
can also be somewhat crowded.

The point of an image viewer is viewing images, not a nice GUI. This is
similar to XV's behaviour.

=item * efficient (and hard to learn) user interface

CV uses key combinations. A lot. If you are an experienced XV user, you
will find most of these keys familiar. If not, CV might be hard to use at
first, but will be an efficient tool later.

=item * multi-window GUI

CV doesn't force you to use a specific layout, instead it relies on your
window manager, thus enabling you to chose whatever layout that suits you
most.

=item * i18n'ed filename handling throughout

As long as glib can recognize your filename encoding (either UTF-8 or
locale-specific, depending on the setting of G_BROKEN_FILENAMES) and you
have the relevant fonts, CV will display your filenames correctly.

=item * extensible through plug-ins

I have weird plug-ins that access remote databases to find a
directory. This is not likely to be of any use to other people. Likewise,
others might have weird requirements I cannot dream of.

=item * filename clustering

Among the standard plug-ins is a filename clustering plug-in, that (in
case of tens of thousands images in one directory) might be able to
cluster similar names together.

=back

=head1 DESCRIPTION

=head2 THE IMAGE WINDOW

You can use the following keys in the image window:

 q            quit the program
 <            half the image size
 >            double the image size
 ,            shrink the image by 10%
 .            enlarge the image by 10%
 n            reset to normal size
 m            maximize to screensize
 M            maximize to screensize, respecting image aspect
 ctrl-m       toggle maxpect-always mode
 u            uncrop
 r            set scaling mode to 'nearest' (fastest)
 s            set scaling mode to 'bilinear' (default)
 shift-s      set scaling mode to 'hyper' (slowest)
 t            rotate clockwise 90°
 T            rotate counterclockwise°
 ctrl-v       open a new visual schnauzer window for the current dir
 ctrl-e       run an editor ($CV_EDITOR or "gimp") on the current image
 ctrl-p       fire up the print fialog
 escape       cancel a crop action

And when playing movies, these additional keys are active:

 left         rewind by 10 seconds
 right        forward by 10 seconds
 down         rewind by 60 seconds
 up           forward by 60 seconds
 pg_up        rewind by 600 seconds
 pg_down      forward by 600 seconds
 o            toggle on-screen display
 p            pause/unpause
 escape       stop playing
 9            turn volume down
 0            turn volume up

Any other keys will be sent to the default schnauzer window, which can be
toggled on and off by right-clicking into the image window.

Left-clicking into the image window will let you crop the image (usually
to zoom into large images that CV scales down).

=head2 THE VISUAL SCHNAUZER

You can use the following keys in the schnauzer window:

 ctrl-space,
 space        move to and display next image
 ctrl-backspace,
 backspace    move to and display previous image
 ctrl-return,
 return       display selected picture, or enter directory

 cursor keys  move selection
 page-up      move one page up
 page-down    move one page down
 home         move to first file
 end          move to last file

 ctrl-a       select all files
 ctrl-shift-a select all files currently displayed in the schnauzer window
 ctrl-d       delete selected files WITHOUT ASKING AGAIN
 ctrl-g       force generation of thumbnais for the selected files
 ctrl-s       rescan current direcory or files updates/deletes etc.
 ctrl-u       update selected (or all) icons if neccessary
 ctrl-l       don't use, will become a plug-in eventually

 ^            go to parent directory (caret).

 0-9,
 a-z          find the first filename beginning with this letter

Right-clicking into the schnauzer window displays a pop-up menu with
additional actions.

=head1 FILES

When starting, CV runs the F<.cvrc> file in your F<$HOME> directory as if
it were a perl script. in that, you will mostly load plug-ins.

Example:

   system "fping -q -t 10 ether"
     or require "/fs/cv/cvplugin.pl";

This will load a plug-in, but only if the machine I<ether> is reachable
(supposedly the plug-in is networked in some way :).

=head1 ENVIRONMENT

=over 4

=item CV_EDITOR

The program that gets executed when the user presses C<CTRL-e> in the
Schnauzer or image window. The default is C<gimp>.

=item CV_PRINT_DESTINATION

The default (perl-style) destination to use in the print dialog.

=item CV_TRASHCAN

When set, must point to a directory where all files that are deleted are
moved to. If unset, files that are deleted are really being deleted.

=back

=head1 SECURITY CONSIDERATIONS

CV uses Pixbuf to load non-JPEG images. Pixbuf is not considered safe for
this purpose, though (from the gtk-2.2 release notes):

"While efforts have been made to make gdk-pixbuf robust against invalid
images, using gdk-pixbuf to load untrusted data is not recommended, due to
the likelyhood that there are additional problems where an invalid image
could cause gdk-pixbuf to crash or worse."

=head1 BUGS/TODO

 Lots of functionality is missing.

 Pixbuf doesn't always honor G_BROKEN_FILENAMES, so accessing files with
 names incompatible with utf-8 might fail.

 rotate on disk
 lots of ui issues
 save(?)
 preferences

=head1 AUTHOR

Marc Lehmann <cv@plan9.de>.

=cut

