#!/usr/bin/perl -w
#
#  "spiral.pl" (a number of other programs call this)
#
#  Draws one or more spirals using the Logo library
#
#  070108 by liverpole
#

# Strict
use strict;
use warnings;

# Libraries
use lib ".";
use Language::Logo;
use Data::Dumper;
use File::Basename;
use Getopt::Long;

# Globals
my $iam  = basename $0;
my $b_toroid = 0;
my $b_reflect = 0;
my $b_debug = 0;
my $bg = "";
my $host = "";
my $b_hide = 0;
my $color = "";
my $update = "";
my $width = "";
my $maxsize = 512;
my $minsize = 8;
my $minang = -1;
my $incr = 2;
my $startsize = 0;
my $nticks = 0;
my $tickcnt = 0;
my $pos = 0;
my $syntax = "

    syntax:  $iam  [switches]  <angle>

    Uses Logo to create a spiral with the specified update and angle.

    The update specifies the update interval of the gui (iterations
    per second between 1 (very fast) and 1000 (very slow)).

    Switches:
        -d ............ starts the Logo server in debug mode
        -t ............ 'toroidal' -- sets wrap to 1
        -r ............ 'reflect'  -- sets wrap to 2
        -h <host> ..... connects to server on given host (':' = localhost)
        -x ............ hides the turtle
        -a <min> ...... use a random angle from <min> to the given <angle>
        -b <color> .... specifies the Canvas background color
        -c <color> .... specifies the pen color
        -u <update> ... specifies the update speed
        -w <width> .... specifies the pen width
        -s <size> ..... specify the starting size
        -i <incr> ..... increment the size each time by <incr>
        -n <nticks> ... change the color after <nticks> 'ticks'
        -p <x,y> ...... make the starting position (X, Y)

";

# Command-line
my $result = GetOptions(
    "d"   => \$b_debug,
    "x"   => \$b_hide,
    "t"   => \$b_toroid,
    "r"   => \$b_reflect,
    "b=s" => \$bg,
    "c=s" => \$color,
    "h=s" => \$host,
    "u=s" => \$update,
    "w=s" => \$width,
    "a=s" => \$minang,
    "s=s" => \$startsize,
    "i=s" => \$incr,
    "n=s" => \$nticks,
    "p=s" => \$pos,
);
$result or die $syntax;
(my $angle = shift) or die $syntax;

# Main program

# Create Logo object
my @opts = (debug => $b_debug);
$bg   and push @opts, bg   => $bg;   # Initial canvas color
$host and push @opts, host => $host; # Connect to an existing server
my $lo = new Logo(@opts);

# Issue logo commands
$update and $lo->cmd("update $update");
if ($startsize) {
    my $half     = $startsize / 2;
    my $quarter  = $half / 2;
    $lo->cmd("rt 90; bk $quarter; lt 90; bk $half");
}
$width     and $lo->cmd("pensize $width");
$color     and $lo->cmd("color   $color");
$b_hide    and $lo->cmd("ht");
$b_toroid  and $lo->cmd("wrap 1");
$b_reflect and $lo->cmd("wrap 2");
if ($pos) {
    ($pos =~ /(\d+),(\d+)/) or die "$iam:  invalid position '$pos'\n";
    my ($x, $y) = ($1, $2);
    $lo->cmd("xy $x $y");
}
$lo->cmd("pendown");

# Create spiral
spiral($startsize, $angle);

# Disconnect from main client
$host or $lo->disconnect("Type [RETURN] to disconnect ... ");


# Subroutines
sub spiral {
    my ($size, $angle) = @_;

    while (($incr <= 0 and $size >= $minsize) ||
        ($incr >= 0 and $size <= $maxsize)) {
        $lo->cmd("forward $size");                 # Move & draw turtle
        if ($minang >= 0) {
            $lo->cmd("rt random $minang $angle");  # Make a random turn
        } else {
            $lo->cmd("rt $angle");                 # Turn <angle> degrees
        }

        # Change pen color randomly
        if ($nticks and ++$tickcnt >= $nticks) {
            $lo->cmd("color random");
            $tickcnt = 0;
        }

        $size += $incr;
    }
}