A simple script for christmas draw. Pass an array of names to find out who is preparing a gift for whom.

christmas_draw.rb

require 'digest'

class ChristmasDraw
  attr_accessor :names

  def initialize(names)
    @names = names
  end

  def call
    initialize_containers
    names.each { |name| draw(name) }
    @results
  end

  private

  def initialize_containers
    @used = []
    @results = {}
  end

  def draw(name)
    drawed_name = drawable_names(name).sample
    update_used(drawed_name)
    update_results(name, drawed_name)
  end

  def drawable_names(name)
    @names - @used - [name]
  end

  def update_used(name)
    @used << name
  end

  def update_results(name, drawed_name)
    encoded_drawed_name = encode(drawed_name)
    @results[name] = encoded_drawed_name
  end

  def encode(name)
    Digest::MD5.hexdigest(name)
  end
end