#!/usr/local/bin/perl -w

use strict;
use diagnostics;
use Tk;
use Tk::Dialog;

my $mw = MainWindow->new;
$mw->geometry("500x225+400+400");
$mw->minsize(qw(500 225));
$mw->maxsize(qw(500 225));
$mw->title("Color Viewer");

my $leftFrm = $mw->Frame(-width => 250,
	-height => 225,
	-borderwidth => 2,
	-relief => 'sunken')
->pack(-side => 'left', -fill => 'y');

my $rightFrm = $mw->Frame(-width => 300,
	-height => 225,
	-borderwidth => 2,
	-relief => 'sunken')
->pack(-side => 'left');

my $redscale = $leftFrm->Scale(-label => 'Red (R)',
	-orient => 'horizontal',
	-from => 0,
	-to => 255,
	-width => 10,
	-sliderlength => 15,
	-length => 200,
	-foreground => 'red',
	-command => \&rgb2hex)->pack(-side => 'top');

my $greenscale = $leftFrm->Scale(-label => 'Green (G)',
	-orient => 'horizontal',
	-from => 0,
	-to => 255,
	-width => 10,
	-sliderlength => 15,
	-length => 200,
	-foreground => 'darkgreen',
	-command => \&rgb2hex)->pack(-side => 'top');

my $bluescale = $leftFrm->Scale(-label => 'Blue (B)',
	-orient => 'horizontal',
	-from => 0,
	-to => 255,
	-width => 10,
	-sliderlength => 15,
	-length => 200,
	-foreground => 'blue',
	-command => \&rgb2hex)->pack(-side => 'top');

my $hexLabel1 = $leftFrm->Label(-text => 'WWW Hex Code',
	-pady => 8)
	->pack(-side => 'top');

my $leftFrm1 = $leftFrm->Frame->pack(-fill => 'x');
my $hexValueEnt = $leftFrm1->Entry(-width => 10)
	->pack(-side => 'left', pady => 2, padx => 2);
$hexValueEnt->insert(0, "#000000");

my $btnHexToRGB = $leftFrm1->Button(-text => 'Hex -> RGB',
	-activebackground => 'purple',
	-highlightbackground => 'purple',
	-command => \&hex2rgb)
->pack(-side => 'left', pady => 2, padx => 2);

# Add a dialog widget
my $dialog = $mw->Dialog;

MainLoop;

sub rgb2hex {
	my $red = $redscale->get();
	my $green = $greenscale->get();
	my $blue = $bluescale->get();

	my $color = sprintf("#%02X%02X%02X", $red, $green, $blue);
	$hexValueEnt->delete(0, 'end');
        $hexValueEnt->insert(0, $color);
	setcolor();
}

# Converts the hex value to rgb
sub hex2rgb {
	my $hex = $hexValueEnt->get();

	if ($hex =~ m/^\#[0-9a-fA-F]+$/ and length($hex) == 7) {
        	my @rgb = split(//, $hex);
        
        	my $red = hex($rgb[1].$rgb[2]);
        	$redscale->set($red);
        	
        	my $green = hex($rgb[3].$rgb[4]);
        	$greenscale->set($green);
        	
        	my $blue = hex($rgb[5].$rgb[6]);
        	$bluescale->set($blue);	
        	
		setcolor();
	}
	else {
		$dialog->configure(-title => 'Invalid Entry', -text => 'Invalid hex code value.');
		$dialog->Show;
	}
}

# Resets the background color of the bottom frame
sub setcolor {
	$rightFrm->configure(-background => $hexValueEnt->get());	
}

__DATA__