isolate command processing

--HG--
branch : nmdc-ircfrontend

TODO.txt

@@ -56,6 +56,8 @@ REF
 
 https://www.alien.net.au/irc/irc2numerics.html
 
+http://faerion.sourceforge.net/doc/irc/whox.var
+
 http://www.anta.net/misc/telnet-troubleshooting/irc.shtml
 
 https://tools.ietf.org/html/rfc2812

server.go

@@ -330,6 +330,19 @@ func (s *Server) handleRegisteredCommand(command string, args []string) {
 			s.DisconnectClient()
 		}
 
+	default:
+		s.handleJoinedCommand(command, args)
+	}
+}
+
+func (s *Server) handleJoinedCommand(command string, args []string) {
+
+	if s.clientState != CSJoined {
+		s.reply(errNotReg)
+		return
+	}
+
+	switch command {
 	case "PART":
 		if len(args) < 1 {
 			s.reply(errMoreArgs)