heuristic detect DC /me messages

NTFServer.go

@@ -289,8 +289,43 @@ func (this *NTFServer) HandleHubMessage(msg upstreamMessage) {
 
 	case libnmdc.EVENT_SYSTEM_MESSAGE_FROM_CONN, libnmdc.EVENT_SYSTEM_MESSAGE_FROM_HUB:
 		// This includes "want to register your nick?" and chat-catchup messages
-		// Don't mirror them into telegram
-		log.Printf("Hub(%s): * %s", msg.hubNick, msg.evt.Message)
+		// But it also includes /me messages
+		// Hard to tell them apart - heuristic detection by matching the first space-separated word against known online users
+
+		isActionMessage := false
+
+		if conn, ok := this.conns[msg.hubNick]; ok {
+			firstWord := strings.SplitN(msg.evt.Message, ` `, 2)[0]
+			_ = conn.Users(func(umap *map[string]libnmdc.UserInfo) error {
+				for knownHubNick, _ := range *umap {
+					if knownHubNick == firstWord {
+						isActionMessage = true
+						return nil
+					}
+				}
+				return nil
+			})
+		}
+
+		if isActionMessage {
+			// Treat it as a full post
+
+			// Coalesce from multiple connections
+			if this.Coalesce("*", msg.evt.Message) {
+				return // ignore - we heard this message already recently
+			}
+
+			// Display the message
+			htmlMsg := "<i>* " + html.EscapeString(msg.evt.Message) + "</i>"
+			err := this.GroupChatSayHTML(htmlMsg)
+			if err != nil {
+				log.Printf("Delivering action message to group chat: %s", err.Error())
+			}
+
+		} else {
+			// Don't mirror them into telegram
+			log.Printf("Hub(%s): * %s", msg.hubNick, msg.evt.Message)
+		}
 
 	case libnmdc.EVENT_CONNECTION_STATE_CHANGED:
 		log.Printf("Hub(%s): * Connection %s", msg.evt.StateChange.String())