gistfile1.rb

#!/usr/bin/env ruby
 
require 'rubygems'
require 'gmail'
 
class SecretSanta
  class << self
    def get_secret_santas(people, couples)
      invalid = true
      while(invalid) do
        invalid = false
        santas = create_possible_matches(people)
        santas.each do |giver, receiver|
          if giver == receiver ||
            giver_and_receiver_are_couples?(giver, receiver, couples)
            invalid = true
          end
        end
      end
      santas
    end
 
    private
 
    def create_possible_matches(people)
      matches = Hash[people.shuffle.zip(people.shuffle)]
    end
 
    def giver_and_receiver_are_couples?(giver, receiver, couples)
      couples.each do |couple|
        return true if couple.include?(giver) && couple.include?(receiver)
      end
      false
    end
  end
end
 
######################
 
people = %w{ James Suzanne Devin Timorah Alex Michelle Nick Kenneth }
couples = [
  %w{ James Suzanne },
  %w{ Devin Timorah },
  %w{ Alex Michelle },
  %w{ Alex Nick }
]
 
santas = SecretSanta.get_secret_santas(people, couples)

p santas