#!/usr/bin/env perl

#use Time::HiRes qw/ usleep /;
use YAML;
use FindBin qw/$Bin/;
use Data::Dumper;
use lib "$Bin/../lib";

use strategy::Scheduler;

my $config = YAML::LoadFile("$Bin/../strategy.yml");
my $sc = new strategy::Scheduler($config);

my $pids = 0;
my $maxpids = $sc->conf->{scheduler}->{num_processes} || ConfigError("scheduler->num_processes not defined");

sub wait_finished_child {
  $pids--;
  wait();
}
$SIG{CHLD} = \&wait_finished_child;

# main program loop
while(1) {
  print "Looking for databases to backup.. [" . scalar localtime() . "]\n";
  my $runs = $sc->db->resultset('Schedule')->get_runs;
  while(my $run = $runs->next) {
    start_new_child();
  }
  sleep(100);
  print "Waiting 600 seconds.. [" . scalar localtime() . "]\n";
}

sub start_new_child {
  if($pids < $maxpids) {
    my $newpid = fork();
    if($newpid > 0) {
      $pids++;
    } elsif(defined $newpid) {
      print "pid: $$ ($pids of $maxpids) spawned\n";
      sleep 2;
      exit(0);
    } else { die $!; }

  } else {
    sleep 60;
  }
}

sub ConfigError {
  my $msg = shift;
  die("Configuration Error: $msg\nConfigfile: ($Bin/../strategy.yml) ");
}