--- a/src/browser/sat_browser/plugin_xep_0085.py	Mon Oct 20 10:00:44 2014 +0200
+++ b/src/browser/sat_browser/plugin_xep_0085.py	Wed Oct 22 14:17:17 2014 +0200
@@ -46,7 +46,8 @@
         self.timer = None
 
     def _onEvent(self, state):
-        """Pyjamas callback takes no extra argument so we need this trick"""
+        # Pyjamas callback takes no extra argument so we need this trick
+
         # Here we should check the value of the parameter "Send chat state notifications"
         # but this costs two messages. It's even better to call chatStateComposing
         # with a doubt, it will be checked by the back-end anyway before sending
@@ -58,25 +59,19 @@
         self.__onEvent(None)
 
     def __onEvent(self, timer):
-        # print "on event %s" % self.next_state
         state = self.next_state
-        self.next_state = ""
+
+        assert(state in TRANSITIONS)
+        transition = TRANSITIONS[state]
+        assert("next_state" in transition and "delay" in transition)
+
         if state != self.state and state == "composing":
             self.host.bridge.call('chatStateComposing', None, self.target_s)
+
         self.state = state
-        if not self.timer is None:
+        if self.timer is not None:
             self.timer.cancel()
 
-        if not state in TRANSITIONS:
-            return
-        if not "next_state" in TRANSITIONS[state]:
-            return
-        if not "delay" in TRANSITIONS[state]:
-            return
-        next_state = TRANSITIONS[state]["next_state"]
-        delay = TRANSITIONS[state]["delay"]
-        if next_state == "" or delay < 0:
-            return
-        self.next_state = next_state
-        # pyjamas timer in milliseconds
-        self.timer = Timer(delay * 1000, self.__onEvent)
+        if transition["next_state"] and transition["delay"] > 0:
+            self.next_state = transition["next_state"]
+            self.timer = Timer(transition["delay"] * 1000, self.__onEvent)  # pyjamas timer is in milliseconds