# State
module State
  def do_use(context)
    raise NotImplementedError.new("#{self.class}##{__method__} が実装されていません")
  end

  def do_alarm(context)
    raise NotImplementedError.new("#{self.class}##{__method__} が実装されていません")
  end

  def do_phone(context)
    raise NotImplementedError.new("#{self.class}##{__method__} が実装されていません")
  end
end

# Context
module Context
  def record_log(message)
    raise NotImplementedError.new("#{self.class}##{__method__} が実装されていません")
  end

  def call_security_center(message)
    raise NotImplementedError.new("#{self.class}##{__method__} が実装されていません")
  end
end

# ConcreteState
class DayState
  include State

  @singleton = self.new

  class << self
    def get_instance
      @singleton
    end
  end

  def do_use(context)
    context.record_log('金庫使用（昼間）')
  end

  def do_alarm(context)
    context.call_security_center('非常ベル（昼間）')
  end

  def do_phone(context)
    context.call_security_center('通話（昼間）')
  end
end

# ConcreteState
class NightState
  include State

  @singleton = self.new

  class << self
    def get_instance
      @singleton
    end
  end

  def do_use(context)
    context.call_security_center('非常ベル（夜間）')
  end

  def do_alarm(context)
    context.call_security_center('非常ベル（夜間）')
  end

  def do_phone(context)
    context.call_security_center('通話（夜間）')
  end
end

# ConcreteContext
class SafeguardSystem
  include Context

  def initialize(hour)
    @state = change_state(hour)
  end

  def set_clock(hour)
    change_state(hour)
  end

  def switch_use
    @state.do_use(self)
  end

  def switch_alarm
    @state.do_alarm(self)
  end

  def switch_phone
    @state.do_phone(self)
  end

  # mediator pattern
  def change_state(hour)
    if hour >= 9 && hour < 17
      @state = DayState.get_instance
    else
      @state = NightState.get_instance
    end
  end

  def record_log(message)
    puts "record_log: #{message}"
  end

  def call_security_center(message)
    puts "call_security_center: #{message}"
  end
end

# main
safeguard_system = SafeguardSystem.new(0)

24.times do |hour|
  safeguard_system.set_clock(hour)
  safeguard_system.switch_use
  safeguard_system.switch_alarm
  safeguard_system.switch_phone
end