#!/usr/bin/perl

use strict;
use warnings;

use Data::Dumper;

package Stat;
use Moose;

has 'val'         => (isa => 'HashRef', is => 'rw');
has 'position'     => (is => 'rw');

sub add_kv {
    my $self = shift;
    my %to_add = @_;
    my ($k, $v);
    $self->{val}->{$k} = $v while (($k, $v) = each %to_add);
}

sub to_s {
    my $self = shift;
    my ($k, $v, $s);
    $s .= $k . "\t" . $v . "\n" while (($k, $v) = each %{$self->{val}});
    return $s;
}

package StatSet;
use Moose;

has 'stats'     => (isa => 'ArrayRef', is => 'rw');

sub add_stat {
    my $self = shift;
    my $stat = shift;
    push @{$self->{stats}}, $stat if $stat;
}

sub report {
    my $self = shift;
    my $s;
    $s .= $_->to_s . "\n" for (sort { $a->position <=> $b->position } @{$self->stats});
    return  $s;
}

package main;

my $set = new StatSet;
my $stat1 = new Stat;
my $stat2 = new Stat;

$stat1->add_kv( color => 'green', size => 'huge' );
$stat1->add_kv( amount => 'some' );
$stat1->position(1);

$stat2->add_kv( color => 'blue', size => 'large', amount => 'many' );
$stat2->position(2);

$set->add_stat($stat1);
$set->add_stat($stat2);

print $set->report;