module PatronusFati
  module MessageParser
    # We receive some messages before we specifically request the abilities of
    # the server, when this happens we'll attempt to map the data using the
    # default attribute ordering that was provided by the Kismet server this
    # client was coded against, this may not be entirely accurate, but will
    # become accurate before we receive any meaningful data.
    def self.parse(msg)
      return unless (raw_data = handle_msg(msg))

      unless (cap = get_model(raw_data[0]))
        warn('Message received had unknown message type: ' + raw_data[0])
        return
      end

      src_keys = cap.enabled_keys.empty? ? cap.attribute_keys : cap.enabled_keys
      cap.new(Hash[src_keys.zip(raw_data[1])])
    end

    protected

    def self.extract_data(data_line)
      data_line.scan(PatronusFati::DATA_DELIMITER).map { |a, b| (a || b).tr("\x01", '') }
    end

    def self.get_model(mdl)
      return unless PatronusFati::MessageModels.const_defined?(model_name(mdl))
      PatronusFati::MessageModels.const_get(model_name(mdl))
    end

    def self.handle_msg(line)
      resp = PatronusFati::SERVER_MESSAGE.match(line)
      return unless resp

      h = Hash[resp.names.zip(resp.captures)]

      [h['header'], extract_data(h['data'])]
    end

    def self.model_name(hdr)
      hdr.downcase.capitalize.to_sym
    end
  end
end