Design Pattern: State and Combination Locks

entered_pin_three_state.rb

class EnteredPinThreeState
  attr_reader :lock, :state_name
  
  def initialize(lock)
    @lock = lock
    @state_name = 'Entered Pin Three State'
  end
  
  def dial_to(number)
    lock.state = lock.entered_wrong_pin_state
  end
  
  def clear
    lock.state = lock.cleared_state
  end
  
  def pull_to_open
    lock.state = lock.unlocked_state
  end
  
  def push_to_lock
    puts 'The lock is already locked'
    puts "  currently in #{state_name}"
  end
end