use strictures 1;

use Benchmark qw/:hireswallclock cmpthese/;
use Getopt::Long::Descriptive;

use Config;

my $attrs_to_bench = {
  plain =>              q|is => 'rw'                                                      |,
  ro =>                 q|is => 'ro'                                                      |,
  default =>            q|is => 'rw', default => sub { {} }                               |,
  lazy_default =>       q|is => 'rw', lazy => 1, default => sub { {} }                    |,
  lazy_default_qsub =>  q|is => 'rw', lazy => 1, default => Sub::Quote::quote_sub q{ {} } |,
};

my $cycles = {
  1 => 'get',
  2 => 'get/set/get',
};

my ($opts, $usage) = describe_options(
  '%c: %o' =>
  [ 'help|h'          => 'Print usage message and exit' ],
  [ 'bench|b:s'       => 'Which benchmarks to run (all|xs|pp)', { default => 'all', regex => qr/^(?:all|xs|pp)$/ } ],
  [ 'lib|l:s@'        => 'Bench against specific lib(s), runs same benches against multiple targets, excluding non-moo benches' ],
  [ 'attr|a:s@'       => 'Which attributes to benchmark (must be defined in-file)' ],
  [ 'cycle|c:i'       => 'Which cycle to run 1 - get, 2 - get/set/get (def 1)', { default => 1 } ],
  [ 'iterations|i:i'  => 'How many iterations in each bench run (def 1000)', { default => 1000 } ],
  [ 'totalruns|total|t:i' => 'How many times to rerun the whole benchmark (def 1)', { default => 1 } ],
  [ 'reuse|r'         => 'Reuse the object between attribute usage runs' ],
  { getopt_conf => [qw/gnu_getopt bundling_override no_ignore_case/] },
);

$usage->die if $opts->{help};

if ($opts->{attr}) {
  my %to_bench = map { $_ => 1 } map { split /\s*,\s*/, $_ } @{$opts->{attr}};

  for (keys %to_bench) {
    die "No such attr '$_'\n" unless $attrs_to_bench->{$_};
  }

  for (keys %$attrs_to_bench) {
    delete $attrs_to_bench->{$_} unless $to_bench{$_};
  }
}

my @libs = map { split /\s*:\s*/, $_ } @{$opts->{lib}}
  if ($opts->{lib});

if (@libs) {
  my $myself = $$;

  for my $lib (@libs) {
    $ENV{PERL5LIB} = join ($Config{path_sep}, $lib, @INC);

    my $pid = fork();
    die "Unable to fork: $!" unless defined $pid;

    if ($pid) {
      wait;
    }
    else {
      print "Benchmarking with $lib\n";
      last;
    }
  }

  exit 0 if $$ == $myself;
}

require Method::Generate::Accessor; # need to pre-load for the XS shut-off to work

my $class_types;

if ($opts->{bench} =~ /all|pp/) {
  {
    local $Method::Generate::Accessor::CAN_HAZ_XS = 0;
    _add_moosey_has (moo => 'Moo');
  }

  _add_moosey_has (moose => 'Moose') unless @libs;
  _add_moosey_has (mouse => 'Mousse') unless @libs;
}

if ($opts->{bench} =~ /all|xs/) {
  if (! $Method::Generate::Accessor::CAN_HAZ_XS)
  {
    die "Requested XS benchmarks but XS isn't available in Method::Generate::Accessor";
  }

  _add_moosey_has (moo_XS => 'Moo');
  _add_moosey_has (mouse_XS => 'Mouse') unless @libs;
}


# Actual Benchmarking
for (1 .. $opts->{totalruns} ) {
  print "Perl $], take $_:\n";

  my $objects;

  for my $use_attrs (0, 1) {
    for my $attr (keys %$attrs_to_bench) {
      printf "\n\nBenching %s ( %s )\n====================\n",
        $attr,
        $use_attrs
          ? sprintf '%s%s cycle', ($opts->{reuse} ? '' : 'new() and ' ), $cycles->{$opts->{cycle}}
          : 'new() only'
        ,
      ;

      cmpthese ( -1, { map {
        my $type = $_;
        "${type}->$attr" => sub {
          $objects->{$type} = $class_types->{$type}->new
            unless ( $use_attrs && $opts->{reuse} );

          for (1 .. $opts->{iterations} ) {
            if ($opts->{cycle} == 1) {
              my $init = $objects->{$type}->$attr;
            }
            elsif ($opts->{cycle} == 2) {
              my $init = $objects->{$type}->$attr;
              $objects->{$type}->$attr('foo') unless $attr eq 'ro';
              my $set = $objects->{$type}->$attr;
            }
          }
        };
      } keys %$class_types } );
    }
  }

  print "\n\n\n";
}

exit 0; # the end

sub _add_moosey_has {
  my ($name, $base) = @_;

  my $class = "Bench::${name}";

  my $perl = "package $class; use $base;";

  for my $attr (keys %$attrs_to_bench) {
    $perl .= "has $attr => ($attrs_to_bench->{$attr});";

    $class_types->{$name} = $class;
  }

  $perl .= 'eval { __PACKAGE__->meta->make_immutable };';

  eval $perl;
  die $@ if $@;
}