class BmtLicenseKey
  
  attr_accessor :license_key, :error
  
  ATTEMPTS = 5
  
  def initialize
    @attempt = 0
  end
  
  def generate!
    @attempt += 1
    self.license_key = Array.new(16) { rand(2) == 0 ? (rand(90-65) + 65).chr : (rand(7) + 50).chr }.join.gsub(/[IO]/, "X")
    existing_license_key = Order.find_by_license_key(license_key)
    if existing_license_key && @attempt < ATTEMPTS
      generate!
    elsif existing_license_key && @attempt == ATTEMPTS
      attempts_failed!
    end
    license_key
  end
  
  def attempts_failed!
    self.license_key = nil
    @attempts_failed = true
  end
  
  def attempts_failed?
    @attempts_failed == true
  end
  
  def to_xml(options = {})
    xml = Builder::XmlMarkup.new
    xml.instruct!
    xml.response do
      xml.registrationkey do
        if attempts_failed?
          xml.errorcode 1
          xml.errormessage "The attempts to generate unique license key failed (#{ATTEMPTS} times)."
        else
          xml.keydata license_key
        end
      end
    end
  end
  
end