#!/usr/bin/env perl

use strict;
use warnings;
use 5.10.0;

use Time::HiRes qw(sleep);
use Term::ReadKey qw(GetTerminalSize);
use File::Slurp;

my @snowflakes = qw(❄ ❅ ❆);
my ($width, $height) = GetTerminalSize();

my $cpu_count = grep { /^processor\s+: [0-9]/ } read_file('/proc/cpuinfo');

while (1) {
   my ($load) = (read_file('/proc/loadavg') =~ m/^([\d.]+)/);
   my $heaviness = int($load / $cpu_count);
   for (0 .. $heaviness) {
       my $flake = $snowflakes[ rand @snowflakes ];
       say ' ' x int(rand($width)) . $flake;
   }

   if ($heaviness > 0) {
       sleep (1 / $heaviness)
   } else {
       sleep .75;
   }
}