#!/usr/bin/perl -w

# Create a random pokey cartoon for xscreensaver
# Waider August 14 2003

# put this into your .xscreensaver to make it work
#     "RandomPokey" randompokeyhack.pl
# and note that the preview won't work in the config front-end

# and also you may be left with /tmp/rpNNNN directories because I'm
# too lazy to do proper cleanup.
use LWP::UserAgent;
use strict;

# 1. get the list of cartoons, so we know how many there are.
# http://www.lysator.liu.se/pokey/archive/
my $ua = new LWP::UserAgent;
$ua->env_proxy();
my $content;

my $req = new HTTP::Request GET => "http://www.lysator.liu.se/pokey/archive/";
my $res = $ua->request( $req );
if ( $res->is_success ) {
  $content = $res->content;
} else {
  die "Can't get index page.\n";
}

# Find the max number off the list
my ( $max ) = $content =~ m/^.*index(\d+).html\D+$/si;
my @images;

# Right, now let's make up a cartoon. If it's over four frames, we'd
# better check if the frames exist.
my $frames = int( rand( 3 )) + 3; # 4 - 7 frames
mkdir ( "/tmp/rp$$" ) || die "someone's trying to hack us";

# Fetch the images into a tmpdir
$req = new HTTP::Request GET => "http://www.lysator.liu.se/pokey/archive/pokey.gif";
$res = $ua->request( $req );
if ( $res->is_success ) {
  saveimg( $res->content, "logo" );
} else {
  die "Can't get pokey logo.\n";
}

while ( 1 ) {
  # Ideally, we'd use GD to play here, but GD may not have GIF support,
  # so DOOM! DOOM!
  # cheeziness ensues
  my $cmd = "/usr/X11R6/bin/xview -quiet -onroot -at 0,0 /tmp/rp$$/logo ";
  my ( $i, @i );
  for $i ( 0..$frames ) {
	$i[ $i ] = int( rand( $max ) + 1 );
	$req = new HTTP::Request GET =>
	  "http://www.lysator.liu.se/pokey/archive/pokey$i[$i]_" . ( $i+1 ) . ".gif";
	$res = $ua->request( $req );
	if ( !$res->is_success ) {
	  last; # end the cartoon here.
	}
	saveimg( $res->content, "$i" );
	$cmd .= "-merge -at 0," . 110 * ( $i + 1 ) . " /tmp/rp$$/$i ";
  }

  # xview can read gifs but not dump them. tools.
  $cmd .= "-clip 0,0,500," . 110 * ( $frames + 1 ) . " -dump jpeg /tmp/rp$$/assembled";
  system( $cmd );
  system( "xview -center -onroot -quiet /tmp/rp$$/assembled" );

  # clean up
  unlink( "/tmp/rp$$/assembled" );
  for my $i ( 0 .. $frames ) {
	unlink( "/tmp/rp$$/$i" );
  }
  sleep( 10 );
}

sub saveimg {
  my ( $data, $name ) = @_;
  open( IMG, ">/tmp/rp$$/$name" ) or die $!;
  binmode( IMG );
  print IMG $data;
  close( IMG );
}

END {
  unlink( "/tmp/rp$$/logo" );
  rmdir( "/tmp/rp$$" );
}