#!/usr/bin/perl
use warnings;
use strict;
use Tk;
use Net::Ping;

my ( $ip, $hostname, $mw, $hostfile, $int, $frame, $stat, %list, $body );

# Process arguements
while ( @ARGV and $ARGV[0] =~ /^-/ ) {
    $_ = shift;
    last if /^--$/;
    if    (/^-f(.*)/) { $hostfile = $1 }
    elsif (/^-i(.*)/) { $int      = $1 }
    else { usage(); }
}

# Set default values if no arguments were supplied
unless ( defined($hostfile) ) { $hostfile = "/etc/hosts" }
unless ( defined($int) )      { $int      = "30" }

open HOSTFILE, "< $hostfile" or die "can't read $hostfile: $!";

# Create a hash of the hostfile; omitting comments, localhost, and
# blank lines 
while (<HOSTFILE>) {
    s/#.*//;    # remove any comments
    next if /^\s+$/;
    next if /^127\./;
    ( $ip, $hostname ) = split;
    $list{$hostname}{hostname} = $hostname;
    $list{$hostname}{ip}       = $ip;

    my ( $status, $color, $p );
    $p = Net::Ping->new("icmp");
    if ( $p->ping( $ip, 1 ) ) {
        $list{$hostname}{status} = "UP";
        $list{$hostname}{color}  = "green";
    }
    else {
        $list{$hostname}{status} = "DOWN";
        $list{$hostname}{color}  = "red";
    }
}

$mw = MainWindow->new();
$mw->title("NetMon Tool");
$mw->geometry('+10+10');
$mw->configure( -background => "black" );

# create topmenu menu
my $tm = $mw->Frame(
    -relief      => 'groove',
    -borderwidth => 3,
    -background  => 'white',
  )->pack(
    -side => 'top',
    -fill => 'x'
  );

# create frames
$body = $mw->Frame( -background => "black", )->pack(
    -side => 'top',
    -fill => 'x'
);

sub pingagain {    # Ping each host once and label UP or DOWN
    my ( $host, $p );
    $p = Net::Ping->new("icmp");
    foreach $host ( keys %list ) {
        if ( $p->ping( $list{$host}{ip}, 1 ) ) {
            $list{$host}{status}    = "UP";
            $list{$hostname}{color} = "green";
            $stat->configure(-background => 'green');            
	}
        else {
            $list{$host}{status}    = "DOWN";
            $list{$hostname}{color} = "red";
            $stat->configure(-background => 'red');
	    
	}
    }
    textdisp();
}

sub textdisp {
    my ($host);

    #	system("clear");
    foreach $host ( keys %list ) {
        print "$list{$host}{hostname}   \t";
        print "$list{$host}{ip}\t";
        print "$list{$host}{status}\n";
    }
}

sub usage {
    print STDERR <<"_EOT_";

Usage: netmon <options>

Where options are:

-i<interval>                    : The interval, in seconds, at
which
netmon should ping hosts
Default: 30
-f<filename>                    : The configuration file
containing
space delimited IP addresses
and
hostnames to be monitored.
Default: /etc/hosts

Example: netmon -i5 -f/tmp/myhostfile

_EOT_
    exit(1);
}

sub statdisp {
    my ($host);
    foreach $host ( keys %list ) {

        $frame = $body->Frame( -background => "$list{$host}{color}", )->pack(
            -side => 'top',
            -fill => 'x'
        );

        $stat = $frame->Label( -background => "$list{$host}{color}" )->pack(
            -padx   => 12,
            -side   => "left",
            -expand => 1,
            -fill   => "x"
        );
        $stat->configure( -text => $list{$host}{hostname} );

        $stat = $frame->Label( -background => "$list{$host}{color}" )->pack(
            -padx   => 16,
            -side   => "left",
            -expand => 1,
            -fill   => "x"
        );
        $stat->configure( -text => $list{$host}{ip} );

        $stat = $frame->Label( -background => "$list{$host}{color}" )->pack(
            -padx => 4,
            -side => "right",
        );
        $stat->configure( -text => "$list{$host}{status}" );
    }
}

textdisp();
statdisp();
$mw->repeat( 1000, \&pingagain );
$mw->update;
MainLoop();