use strict;
use warnings;

use ntheory ":all";
use MCE::Flow;

my ( $name, $rng );

my %rand = (
  "drand48" => sub { int(rand(1 << 32)) },
  "ChaCha20" => sub { irand64() },
  "/dev/urandom" => sub { unpack("Q", random_bytes(8)) }
);

MCE::Flow::init(
  max_workers => 8,
  init_relay  => 0,
  user_begin  => sub {
    $name = MCE->user_args()->[0];
    $rng  = $rand{ $name };
  }
);

sub func {
  MCE::relay {
    print MCE->wid(), ": ", $rng->(), "\n";
  };
}

for my $name ( "drand48", "ChaCha20", "/dev/urandom" ) {
  print "Usage $name:\n";
  mce_flow { user_args => [$name] }, \&func;
  print "\n";
}


##</code><code>##

Usage drand48:
1: 3498494761
2: 2506930441
3: 1515366121
4: 523801801
5: 3827204777
6: 2835640457
7: 1844076137
8: 852511817

Usage ChaCha20:
1: 4471005142860083063
2: 4471005142860083063
3: 4471005142860083063
4: 4471005142860083063
5: 4471005142860083063
6: 4471005142860083063
7: 4471005142860083063
8: 4471005142860083063

Usage /dev/urandom:
1: 15746895497052787399
2: 15746895497052787399
3: 15746895497052787399
4: 15746895497052787399
5: 15746895497052787399
6: 15746895497052787399
7: 15746895497052787399
8: 15746895497052787399


##</code><code>##

Usage drand48:
1: 600074529
2: 3903477505
3: 2911913185
4: 1920348865
5: 928784545
6: 4232187521
7: 3240623201
8: 2249058881

Usage ChaCha20:
1: 8740887910466299010
2: 12948789762855324085
3: 7574729187958724006
4: 14608687740989597345
5: 10145950054018120246
6: 11767641523694169551
7: 5811941457879652367
8: 2397613489984096139

Usage /dev/urandom:
1: 14391656456731294109
2: 2750708286643159769
3: 10844675827853246458
4: 7920672879166021322
5: 16939013845838223421
6: 9482848646152826462
7: 11535629003375292447
8: 6903845178044907896