def set_mode(mode)
      case mode
      # when "+s"
      # when "-s"
      when "+i"
        room.lock
        room.locked = true
        client.user_reply :mode, channel,
          current_mode_string, room.membership_limit
      when "-i"
        room.unlock
        room.locked = false
        client.user_reply :mode, channel,
          current_mode_string, room.membership_limit
      else
        client.numeric_reply :err_unknownmode,
          "is unknown mode char to me for #{channel}"
      end
    end
def set_mode(mode)
      case mode
      # when "+s"
      # when "-s"
      when "+i"
        room.lock
        room.locked = true
        client.user_reply :mode, channel,
          current_mode_string, room.membership_limit
      when "-i"
        room.unlock
        room.locked = false
        client.user_reply :mode, channel,
          current_mode_string, room.membership_limit
      else
        client.numeric_reply :err_unknownmode,
          "is unknown mode char to me for #{channel}"
      end
    end
Public: set the mode on the campfire channel, mapping from the provided
 IRC chanmode to the campfire setting.

 mode - the IRC mode flag change. Must be one of:
        "+i" - lock room
        "-i" - unlock room

 TODO support these when the firering client does:
        "+s" - disable guest access
        "-s" - enable guest access

 Returns nothing, but lets the client know the results of the call. Sends
   an error to the client for an invalid mode string.