#!/usr/bin/perl

use strict;
use warnings;
use Tk;
use Tk::IO;
use Tk::ROText;

my $entry_var='';
my $pid;
my $mw = MainWindow->new(-title => 'Tk::IO');
$mw->geometry('570x500');
my $top_frame = $mw->Frame(
	-relief => 'groove', 
	)->pack(-side=> 'top', -fill => 'x');
my $top_frame_left = $top_frame->Frame(
	-relief => 'groove',
	)->pack(-side => 'left',-fill => 'x');
my $top_frame_right = $top_frame->Frame(
	-relief => 'groove',
	)->pack(-side => 'right', -fill=>'x');

my $bot_frame = $mw->Frame(
	-relief => 'groove', 
	-borderwidth => 5
	)->pack(-side=> 'bottom', -expand => 1,-fill => 'both');
my $clear_button = $top_frame_left->Button(
	-text => 'Clear',
	-command => sub { &clear_text }
	)->pack(-side => 'left');
my $start_button = $top_frame_left->Button(
	-text => 'Start',
	-command => sub { &go }
	)->pack(-side => 'left');
my $stop_button = $top_frame_left->Button(
	-text => 'Stop',
	-state => 'disabled',
	-command => sub { &stop }
	)->pack(-side => 'left');
my $label = $top_frame_left->Label(
	-text => 'Enter Host'
	)->pack(-side => 'left');
my $entry = $top_frame_left->Entry(
	-textvariable => \$entry_var
	)->pack(-side => 'left');
my $exit_button = $top_frame_right->Button(
	-text => 'Exit',
	-command => sub { exit }
	)->pack(-side => 'right');
my $text_box = $bot_frame->Scrolled(
	'ROText',
	-wrap => 'word',
	-font => 'rk24',
	-background => 'black',
	-foreground => 'green',
	-scrollbars => 'se'
	)->pack(-expand => 1, -fill => 'both');

MainLoop;

sub go {
	if($entry_var eq ''){
		$text_box->insert('end',"No host specified\n");
		return;
	}
	$start_button->configure(-state => 'disabled');
	$stop_button->configure(-state => 'active');
	
	my $usr_command = Tk::IO->new(
		-linecommand => sub 
			{ $text_box->insert('end', shift()) },
		-childcommand => sub {
			$text_box->yview('end');
			$start_button->configure(-state => 'active');
			$stop_button->configure(-state => 'disabled')});
		$pid = $usr_command
		->exec("nmap $entry_var 2>&1") or die $!;
}

sub stop {
	kill INT =>  $pid if kill 0 => $pid;
	$start_button->configure(-state=>'active');
	$stop_button->configure(-state=>'disabled');
	$text_box->insert('end', "Cancelled...\n");
	$text_box->yview('end');
}

sub clear_text {
	$text_box->delete('0.0','end');
}