#!/usr/bin/perl

use POSIX qw(setsid);

chdir '/';
umask 0;
open STDIN, '/dev/null' || die "Can't read /dev/null: $!";
open STDOUT, '>/dev/null' || die "Can't write /dev/null: $!";
open STDERR, '>/dev/null' || die "Can't write /dev/null: $!";

defined(my $pid = fork) || die "Can't fork: $!";
exit if $pid;
setsid or die "Can't start new session: $!";
$ENV{'PATH'} = $ENV{'PATH'} . ":/usr/local/opt/sbin";
system 'rmmod powermate';
system 'grifcat --led-pulse';

open GRIFFIN, "grifcat --minimal|" || die "Failed to open grifcat: $!";
while(<GRIFFIN>) {
  chomp;
  ($b, $d) = split(/ /);
  if($b && !$lb) {
    system "mpc next\n";
  }
  if($d && !$b) {
    $d*=3;
    $d=~s/^(\d)/+$1/;
    system "mpc volume $d\n";
  }
  ($lb, $lt) = ($b,$t);
}