#! /usr/bin/perl

# colon1.pl    -    Draw a scalable : (colon) on a canvas
#                   Test script for a planned addition to Tk::LCD.pm
#                   Tk::LCD defines elements within a 22 x 36 pixel rectangle
#                   The colon is drawn as two circles within this rectangle
#
#                   @Base shapes are scaled and moved into @scaled shapes for display
#                   Clicking the Next buttons rescales and redraws the screen
#
# James M. Lynes, Jr. - KE4MIQ
# Created:       March 14, 2023
# Last Modified: 03/14/2023 - Initial Version
#                03/15/2023 - First working version
#
# Environment:   Ubuntu 22.04LTS
#
# Notes:         Install Perl Tk and non-core modules
#                    sudo apt update
#                    sudo apt install perl-tk

use strict;
use warnings;
use Tk;

my @baseBox      = (0, 0, 22, 0, 22, 36, 0, 36);    # Base Rectangle bounding box
my @baseTopColon = (8, 9, 14, 15);                  # Base Circle bounding box
my @baseBotColon = (8, 21, 14, 27);                 # Base Circle bounding box

my @scaledBox;                                      # Scaled Rectangle
my @scaledTopColon;                                 # Scaled Circle Top
my @scaledBotColon;                                 # Scaled Circle Bottom

my $scale     = 1;                                  # Base scale factor
my $baseelw   = 22;                                 # Base element width
my $selw      = $baseelw * $scale;                  # Scaled element width

scale(\@scaledBox, \@scaledTopColon, \@scaledBotColon);    # Initial scaling

# Define the Widgets
my $mw     = MainWindow->new();
my $button = $mw->Button(-text => 'next',
                         -command => [\&scale, \@scaledBox, \@scaledTopColon,
                                      \@scaledBotColon])
                         ->pack(-side => 'bottom');
                         
my $canvas = $mw->Canvas()->pack;
$canvas->createPolygon(@scaledBox,   -fill => 'darkgreen');
$canvas->createOval(@scaledTopColon, -fill => 'yellow');
$canvas->createOval(@scaledBotColon, -fill => 'yellow');

$mw->repeat(1000, \&redraw);                        # Redraw the screen, 1 sec cycle
MainLoop;

# Scale the box and colon circles by a scale factor
sub scale {
    my($bx, $tc, $bc) = @_; 

    $selw  = $baseelw * $scale;                      # Scale the element width
    
    $bx = [map {$_ * $scale} @baseBox];              # Scale elements
    $tc = [map {$_ * $scale} @baseTopColon];
    $bc = [map {$_ * $scale} @baseBotColon];

    foreach my $i(0 .. $#$bx) {                      # Return scaled elements
        $_[0][$i] = @$bx[$i];                        #    via references
    }
    foreach my $i(0 .. $#$tc) {
        $_[1][$i] = @$tc[$i];
    }
    foreach my $i(0 .. $#$bc) {
        $_[2][$i] = @$bc[$i];
    }
    $scale = $scale + 1;                             # Bump for next cycle
    return;
}

# Timed redraw of the canvas to show the updates
sub redraw {
    $canvas->delete('all');
    $canvas->createPolygon(@scaledBox,   -fill => 'darkgreen');
    $canvas->createOval(@scaledTopColon, -fill => 'yellow');
    $canvas->createOval(@scaledBotColon, -fill => 'yellow');   
    return;
}