c.rb

# frozen_string_literal: true

require 'delegate'

class Deck < DelegateClass(::Hash)
  attr_reader :choosen

  def initialize(choosen = nil, **initial)
    super(initial)

    @choosen =
      if choosen
        raise ArgumentError, "Invalid key: #{choosen}" unless initial.key? choosen

        choosen
      else
        keys.first
      end
  end

  def shuffle
    lookup = keys.zip(new_keys = keys.shuffle).to_h.invert

    self.class.new(lookup[@choosen], **keys.zip(values_at(*new_keys)).to_h)
  end

  def shuffle!
    @choosen = (new_deck = shuffle).choosen
    replace new_deck

    self
  end

  def choosen_value
    self[choosen]
  end

  def self.[](...)
    new(...)
  end
end

d = Deck[A: 1, B: 2, C: 3, D: 4, E: 5]

pp d
pp d.values
pp d.choosen
pp d.choosen_value

d.shuffle!

pp d
pp d.values
pp d.choosen
pp d.choosen_value