#!/usr/bin/perl -w

#

# update_slim_wmlist, based on:

# update_wdm_wmlist, (c) 1998 Marcelo Magallón <mmagallo@debian.org>

# rewriten to use the x-window-manager alternative

# modified to also use the x-session-manager alternative by Arthur Korn

# Copyright 2000 Wichert Akkerman <wakkerma@debian.org>

# Modified to use the freedesktop.org .desktop like kdm and gdm

#

# This script will read the list of installed window managers from

# the freedesktop .desktop files in <etc>/X11/sessions/:<etc>/dm/Sessions/:

# <share>/xsessions/

# and update the sessions line in /etc/slim.conf.

# BEWARE: It doesn't ask any questions about this. It just does it. It

# takes an optional list of window managers.

use strict;

use File::DesktopEntry;

my $wm_list='';

my %desktop_files;

unless (@ARGV) {

    #my @wm_list = ('default');

    my @wm_list;

    foreach my $dir ('/etc/X11/sessions/','/etc/dm/Sessions/','/usr/share/xsessions/') {

	    next unless (opendir DIR, $dir);

	    my @files;

	    @files = grep { /\.desktop$/ && -r "$dir/$_" } readdir(DIR);

	    foreach my $file (@files) {

		   push @{$desktop_files{$file}}, "$dir/$file";

	    }

    }

    DESKTOP: foreach my $desktop_file (keys(%desktop_files)) {

	    foreach my $file (@{$desktop_files{$desktop_file}}) {

		    my $entry = File::DesktopEntry->new_from_file($file);

		    next DESKTOP if (defined($entry->get_value('Hidden'))

			and $entry->get_value('Hidden') eq 'true');

		    if ($entry->get_value('Name') =~ /^gnome$/i) {

			    push (@wm_list, 'gnome');

		    }

		    elsif ($entry->get_value('Name') =~ /^kde$/i) {

			    push (@wm_list, 'kde');

		    }

		    elsif (defined($entry->get_value('Exec'))) {

			    push (@wm_list, $entry->get_value('Exec'));

		    }

		    else { # not found, go to next file

			    next;

		    }

		    # found, proceed to next destop file

		    next DESKTOP;

	    }

    }

   $wm_list = join (',', sort @wm_list) . ',custom';

} else {

    $wm_list = join (',', sort @ARGV);

}

open (SLIM_CONFIG_FILE, '

    or die "Can't open /etc/slim.conf for reading: $!";

open (NEW_SLIM_CONFIG_FILE, '>/etc/slim.conf.new')

    or die "Can't open /etc/slim.conf.new for writing: $!";

while (<SLIM_CONFIG_FILE>) {

    s|^(sessions\s*).*|$1$wm_list|;

    print NEW_SLIM_CONFIG_FILE;

}

close(SLIM_CONFIG_FILE);

close(NEW_SLIM_CONFIG_FILE);

rename '/etc/slim.conf.new', '/etc/slim.conf'

    or die "Can't rename /etc/slim.conf.new: $!";

exit 0;