Move the room name code into a separate function.

src/Scylla/Model.elm

@@ -1,6 +1,6 @@
 module Scylla.Model exposing (..)
 import Scylla.Api exposing (..)
-import Scylla.Sync exposing (SyncResponse, HistoryResponse, JoinedRoom, senderName)
+import Scylla.Sync exposing (SyncResponse, HistoryResponse, JoinedRoom, senderName, roomName, roomJoinedUsers)
 import Scylla.Login exposing (LoginResponse, Username, Password)
 import Scylla.UserData exposing (UserData)
 import Scylla.Route exposing (Route(..), RoomId)
@@ -72,6 +72,25 @@ type Msg =
 displayName : Model -> Username -> String
 displayName m s = Maybe.withDefault (senderName s) <| Maybe.andThen .displayName <| Dict.get s m.userData
 
+roomDisplayName : Model -> JoinedRoom -> String
+roomDisplayName m jr =
+    let
+        customName = roomName jr
+        roomUsers = List.filter ((/=) m.loginUsername) <| roomJoinedUsers jr
+        singleUserName = if List.length roomUsers == 1 then List.head roomUsers else Nothing
+        singleUserDisplayName = Maybe.andThen
+            (\u -> Maybe.andThen .displayName <| Dict.get u m.userData) singleUserName
+        firstOption d os = case os of
+            [] -> d
+            ((Just v)::_) -> v
+            (Nothing::xs) -> firstOption d xs
+    in
+        firstOption "<No Name>"
+            [ customName
+            , singleUserDisplayName
+            , singleUserName
+            ]
+
 roomUrl : String -> String
 roomUrl s = Url.Builder.absolute [ "room", s ] []
 

src/Scylla/Views.elm

@@ -107,14 +107,7 @@ homeserverView m hs rs =
 roomListElementView : Model -> String -> JoinedRoom -> Html Msg
 roomListElementView m s jr =
     let
-        roomUsers = List.filter ((/=) m.loginUsername) <| roomJoinedUsers jr
+        name = roomDisplayName m jr
-        privateChatName = case (List.length roomUsers) of
-            1 -> Maybe.andThen (\u -> Maybe.andThen .displayName <| Dict.get u m.userData) <| List.head roomUsers
-            _ -> Nothing
-        maybeRoomName = case roomName jr of
-            Just rn -> Just rn
-            Nothing -> privateChatName
-        name = Maybe.withDefault "<No Name>" maybeRoomName
     in
         div [ class "room-link-wrapper" ]
             [ a [ href <| roomUrl s ] [ text name ]
@@ -169,7 +162,7 @@ joinedRoomView m roomId rd =
             ]
     in
         div [ class "room-wrapper" ]
-            [ h2 [] [ text <| Maybe.withDefault "<No Name>" <| roomName rd.joinedRoom ]
+            [ h2 [] [ text <| roomDisplayName m rd.joinedRoom ]
             , messagesWrapper
             , typingWrapper
             , messageInput