#! /usr/bin/perl

 # client-gui.pl - a simple socket client GUI

 use strict;
 use Socket;
 use Gtk2;


 # initialize some variables

 my $port = 7890;     # hard coded port the server runs on
                     # we could have made this an argument instead


 # used by the hbox, vbox and widget packing

 my $homogenous = 0;  # a "1" here would make all
                  # widgets the same height or width

 my $spacing = 0;     # spacing between widgets in pixels

 my $expand = 1;      # widgets expand to fit available space

 my $fill = 0;        # extra space used by widgets or empty

 my $padding = 0;     # no padding


 # build the GUI

 Gtk2->init(\@ARGV);


 my $window = Gtk2::Window->new('toplevel');

 $window->set_title("Network 'w' Monitor GUI");

 $window->set_border_width(6);

 $window->set_size_request(400, 180);


 my $vbox = Gtk2::VBox->new($homogenous, $spacing);

 my $hbox = Gtk2::HBox->new($homogenous, $spacing);

 my $label_host = Gtk2::Label->new("Hostname to poll:");

 my $entry_host = Gtk2::Entry->new;

 my $text_result = Gtk2::TextView->new;

 my $scrolled_window = Gtk2::ScrolledWindow->new(undef, undef);

 $scrolled_window->set_policy('automatic', 'automatic');

 $scrolled_window->add($text_result);


 my $buffer = $text_result->get_buffer;

 $text_result->set_editable(0);


 my $button_poll = Gtk2::Button->new_with_label("Poll");

 my $button_exit = Gtk2::Button->new_with_label("Exit");


 $hbox->pack_start($label_host, $expand, $fill, $padding);

 $hbox->pack_start($entry_host, $expand, $fill, $padding);


 $vbox->pack_start($hbox, $expand, $fill, $padding);

 $vbox->pack_start($scrolled_window, $expand, $fill, $padding);

 $vbox->pack_start($button_poll, $expand, $fill, $padding);

 $vbox->pack_start($button_exit, $expand, $fill, $padding);


 Gtk2::GSignal->connect($button_poll,"clicked", \&poll_host);

 Gtk2::GSignal->connect($button_exit,"clicked", \&exit_app);


 $window->add($vbox);

 $window->show_all();


 # Gtk2 event loop

 Gtk2->main();

 exit 0;


 # exit routine

 sub exit_app {
    Gtk2->quit();
    return 0;

 }


 # poll routine

 sub poll_host {
    my $host = $entry_host->get_text;
    if ($host eq '') {
        gui_err("Empty Host Name!");
        return;
    }
   my $buff = '';
    my $proto = getprotobyname('tcp');

    # get the port address
    my $iaddr = inet_aton($host);
    my $paddr = sockaddr_in($port, $iaddr);

    # create the socket, connect to the port
    socket(SOCKET, PF_INET, SOCK_STREAM, $proto) or gui_err("socket: $!");
    connect(SOCKET, $paddr) or gui_err("connect: $!");
    while (<SOCKET>) {
        $buff .= $_;
    }
    close SOCKET or gui_err("close: $!");
    $buffer->set_text($buff, -1) if ($buff ne '');

 }


 # error feedback

 sub gui_err {
    my $msg = shift;
    $buffer->set_text($msg, -1);

 }