Example Twilio IVR State Machine

twilio-ivr.rb

require 'ivrflow'

class CCard < Ivrflow
  attr_accessor :asked_for_card_times

  desc <<-END
This workflow represents a caller registering a Credit Card.
During the registration, after they've entered their credit
card number, we attempt to upsel them on 
  END

  define_workflow do
    state :start, :start => true do
      transitions_to :reask_for_card_number,      :if => :not_card_number_valid?
      transitions_to :ask_for_expensive_services, :if => :card_number_valid?
    end

    state :reask_for_card_number, :on_entry => :reasked_for_card_number do
      transitions_to :abuse_caller_and_hangup,    :if => :reask_for_card_number_more_than_3_times?
      transitions_to :reask_for_card_number,      :if => :not_card_number_valid?
      transitions_to :ask_for_expensive_services, :if => :card_number_valid?
    end

    state :ask_for_expensive_services do
      transitions_to :weve_got_a_live_one,    :if => :pressed_1?
      transitions_to :scare_user_and_hang_up, :if => :not_pressed_1?
    end

    state :weve_got_a_live_one do
      transitions_to :thank_user_and_hang_up,  :if => :pressed_1?
      transitions_to :scare_user_and_hang_up,  :if => :not_pressed_1?
    end

    state :thank_user_and_hang_up,  :stop => true
    state :scare_user_and_hang_up,  :stop => true
    state :abuse_caller_and_hangup, :stop => true
  end

  def initialize
    self.asked_for_card_times = 0
    super
  end

  def card_number_valid?
    digits.size == 16
  end

  message :start do
    gather(:numDigits => 16, :timeout => 20) do
      say "Welcome to the La Cosa Nostra credit card activation system."
      say "Please enter your 16 digit card number."
    end
  end

  def reasked_for_card_number
    @asked_for_card_times += 1
  end

  message :reask_for_card_number do
    retries = 3 - asked_for_card_times
    gather(:numDigits => 16, :timeout => 20) do
      say "Oh, you're a real smart guy aren't you?"
      say "You have #{retries+1} chances left."
      say "Enter your 16 digit card number for real this time!"
    end
  end


  message :ask_for_expensive_services do
    gather(:numDigits => 1, :timeout => 20) do
      say "Hey, well done there."
      say "Listen, somebody could steal your identity and make charges on your card."
      say "You want we should break their legs?"
      say "This protection is only $99 a month."
      say "To accept this contract press 1, otherwise press 2."
      say "Don't say we didn't warn you."
    end
  end

  def reask_for_card_number_more_than_3_times?
    @asked_for_card_times >= 3
  end

  message :weve_got_a_live_one do
    gather(:numDigits => 1, :timeout => 20) do
      say "It is a reasonable person indeed who values protection."
      say "If you'd like us to take care of these scumbags before they cause you any trouble, press 1."
      say "Otherwise press 2."
    end
  end

  message :thank_user_and_hang_up do
    say "Consider it done.  We value your friendship and one day will ask you for a favor."
    say "Until that time, know that we are watching.  Goodbye."
    hangup
  end

  message :scare_user_and_hang_up_message do
    say "It's a dangerous world out there!  Watch your back wiseguy!"
    hangup
  end

  message :abuse_caller_and_hangup do
    say "Whats amatter you?  Forget about it."
    hangup
  end
end