app.rb

require 'sinatra'
require 'sinatra/json'
require 'twilio-ruby'
require 'rack/ssl'
require 'active_support/core_ext/time'
require File.expand_path('../lib/twilio_service', __FILE__)
require File.expand_path('../lib/state_handler', __FILE__)
require File.expand_path('../lib/phone_number_processor', __FILE__)
require File.expand_path('../lib/message_generator', __FILE__)
require File.expand_path('../lib/balance_log_analyzer', __FILE__)

class EbtBalanceSmsApp < Sinatra::Base
  use Rack::SSL unless settings.environment == :development or settings.environment == :test
  if settings.environment == :production
    set :url_scheme, 'https'
  else
    set :url_scheme, 'http'
  end
  set :phone_number_processor, PhoneNumberProcessor.new

  configure :production do
    require 'newrelic_rpm'
  end

  helpers do
    def valid_phone_number?(phone_number)
      contains_good_number_of_phone_digits?(phone_number) && !one_of_our_twilio_numbers?(phone_number)
    end

    def contains_good_number_of_phone_digits?(phone_number)
      is_it_valid = (phone_number.length == 10) || (phone_number.length == 11 && phone_number[0] == '1')
      is_it_valid
    end

    def one_of_our_twilio_numbers?(phone_number)
      formatted_phone_number = convert_to_e164_phone_number(phone_number)
      settings.phone_number_processor.twilio_number?(formatted_phone_number)
    end

    def convert_to_e164_phone_number(phone_number)
      if phone_number.length == 10
        '+1' + phone_number
      elsif phone_number.length == 11
        '+' + phone_number
      end
    end
  end

  before do
    puts "Request details — #{request.request_method} #{request.url}" unless settings.environment == :test
  end

  post '/' do
    twilio_service = TwilioService.new(Twilio::REST::Client.new(ENV['TWILIO_SID'], ENV['TWILIO_AUTH']))
    texter_phone_number = params["From"]
    inbound_twilio_number = params["To"]
    state_abbreviation = params["ToState"] || "no_state_abbreviation_received"
    state_handler = StateHandler.for(state_abbreviation)
    ebt_number = state_handler.extract_valid_ebt_number_from_text(params["Body"])
    twiml_url = "#{settings.url_scheme}://"
    twiml_url << "#{request.env['HTTP_HOST']}/get_balance"
    twiml_url << "?phone_number=#{texter_phone_number}"
    twiml_url << "&twilio_phone_number=#{inbound_twilio_number}"
    twiml_url << "&state=#{state_abbreviation}"
    twiml_url << "&ebt_number=#{ebt_number}"
    twiml_url << "&balance_check_id=#{SecureRandom.hex}"
    language = settings.phone_number_processor.language_for(inbound_twilio_number)
    message_generator = MessageGenerator.new(language)
    # Need to rescue Twilio API errors
    begin
      if ebt_number != :invalid_number
        twilio_service.send_text(
          to: texter_phone_number,
          from: inbound_twilio_number,
          body: message_generator.thanks_please_wait
        )
        twilio_service.make_call(
          url: twiml_url,
          to: state_handler.phone_number,
          from: inbound_twilio_number,
          method: "GET"
        )
      elsif params["Body"].downcase.include?('about')
        twilio_service.send_text(
          to: texter_phone_number,
          from: inbound_twilio_number,
          body: message_generator.more_info
        )
      else
        twilio_service.send_text(
          to: texter_phone_number,
          from: inbound_twilio_number,
          body: message_generator.sorry_try_again(state_handler.allowed_number_of_ebt_card_digits)
        )
      end
    rescue Twilio::REST::RequestError => e
      puts "Twilio API request error - \"#{e.message}\""
    end
  end

  get '/get_balance' do
    phone_number = params[:phone_number].strip
    twilio_number = params[:twilio_phone_number].strip
    balance_check_id = params[:balance_check_id]
    state = params[:state]
    state_handler = StateHandler.for(state)
    Twilio::TwiML::Response.new do |r|
      r.Play digits: state_handler.button_sequence(params['ebt_number'])
      r.Record transcribe: true,
        transcribeCallback: "#{settings.url_scheme}://#{request.env['HTTP_HOST']}/#{state}/#{phone_number}/#{twilio_number}/#{balance_check_id}/send_balance",
        timeout: 10,
        maxLength: state_handler.max_message_length
    end.text
  end

  post '/get_balance' do
    # Twilio posts unused data here; necessary simply to avoid 404 error in logs
    response = <<EOF
<?xml version="1.0" encoding="UTF-8"?>
<Response>
</Response>
EOF
  end

  post '/:state/:to_phone_number/:from_phone_number/:balance_check_id/send_balance' do
    twilio_phone_number = params[:from_phone_number]
    language = settings.phone_number_processor.language_for(twilio_phone_number)
    handler = StateHandler.for(params[:state])
    processed_balance_response_for_user = handler.transcribe_balance_response(params["TranscriptionText"], language)
    twilio_service = TwilioService.new(Twilio::REST::Client.new(ENV['TWILIO_SID'], ENV['TWILIO_AUTH']))
    twilio_service.send_text(
      to: params[:to_phone_number].strip,
      from: params[:from_phone_number],
      body: processed_balance_response_for_user
    )
  end

  post '/voice_call' do
    twilio_service = TwilioService.new(Twilio::REST::Client.new(ENV['TWILIO_SID'], ENV['TWILIO_AUTH']))
    caller_phone_number = params["From"]
    inbound_twilio_number = params["To"]
    state_handler = StateHandler.for(params["ToState"])
    language = settings.phone_number_processor.language_for(inbound_twilio_number)
    message_generator = MessageGenerator.new(language)
    response = <<EOF
<?xml version="1.0" encoding="UTF-8"?>
<Response>
  <Gather timeout="10" action="http://twimlets.com/forward?PhoneNumber=#{state_handler.phone_number}" method="GET" numDigits="1">
    <Play>#{message_generator.call_in_voice_file_url}</Play>
  </Gather>
  <Redirect method="GET">http://twimlets.com/forward?PhoneNumber=#{state_handler.phone_number}</Redirect>
</Response>
EOF
  end

  post '/welcome' do
    puts "/welcome request params: #{params}" unless settings.environment == :test
    digits_only_input = params['texter_phone_number'].gsub(/\D/, "")
    if valid_phone_number?(digits_only_input)
      formatted_phone_number = convert_to_e164_phone_number(digits_only_input)
      inbound_twilio_number = params["inbound_twilio_number"]
      language = settings.phone_number_processor.language_for(inbound_twilio_number)
      message_generator = MessageGenerator.new(language)
      twilio_service = TwilioService.new(Twilio::REST::Client.new(ENV['TWILIO_SID'], ENV['TWILIO_AUTH']))
      twilio_service.send_text(
        to: formatted_phone_number,
        from: inbound_twilio_number,
        body: message_generator.welcome
      )
      "Great! I just sent you a text message with instructions. I hope you find this service useful!"
    else
      "Sorry! That number doesn't look right. Please go back and try again."
    end
  end

  get '/.well-known/status' do
    client = Twilio::REST::Client.new(ENV['TWILIO_SID'], ENV['TWILIO_AUTH'])
    messages = client.account.messages.list
    delay_analysis = BalanceLogAnalyzer::DelayedBalanceResponseAnalysis.new(messages)
    response_hash = Hash.new
    response_hash[:dependencies] = [ "twilio" ]
    response_hash[:updated] = Time.now.to_i
    response_hash[:resources] = {}
    if delay_analysis.messages_delayed?
      response_hash[:status] = delay_analysis.problem_description
    else
      response_hash[:status] = 'ok'
    end
    json response_hash
  end
end