Phone Number

phone_number.rb

class PhoneNumber
  attr_reader :number
  
  def initialize(number)
    @number = authenticate(number)
  end
  
  def to_s
    "(#{area_code}) #{number[3..5]}-#{number[6..9]}"
  end
  
  def authenticate(number)
    number.gsub!(/\W/, '')
    number.slice!(0) if number =~ /^1{1}\d{10}$/
    if number =~ /^\d{10}$/
      number
    else
      '0000000000'
    end
  end

  def area_code
    number[0..2]
  end
end