Add "typing people wrapper"

src/Scylla/Sync.elm

@@ -269,11 +269,19 @@ uniqueByRecursive f l s = case l of
 uniqueBy : (a -> comparable) -> List a -> List a
 uniqueBy f l = uniqueByRecursive f l Set.empty
 
+findFirst : (a -> Bool) -> List a -> Maybe a
+findFirst cond l = case l of
+    x::xs -> if cond x then Just x else findFirst cond xs
+    [] -> Nothing
+
+findLast : (a -> Bool) -> List a -> Maybe a
+findLast cond l = findFirst cond <| List.reverse l
+
 findFirstBy : (a -> comparable) -> (a -> Bool) -> List a -> Maybe a
-findFirstBy sortFunction cond l = List.head <| List.sortBy sortFunction <| List.filter cond l
+findFirstBy sortFunction cond l = findFirst cond <| List.sortBy sortFunction l
 
 findLastBy : (a -> comparable) -> (a -> Bool) -> List a -> Maybe a
-findLastBy sortFunction cond l = List.head <| List.reverse <| List.sortBy sortFunction <| List.filter cond l
+findLastBy sortFunction cond l = findLast cond <| List.sortBy sortFunction l
 
 findFirstEvent : ({ a | originServerTs : Int } -> Bool) -> List { a | originServerTs : Int } -> Maybe { a | originServerTs : Int }
 findFirstEvent = findFirstBy .originServerTs
@@ -407,6 +415,13 @@ joinedRoomsEvents s =
     <| Maybe.andThen .join s.rooms
 
 -- Business Logic: User Extraction
+roomTypingUsers : JoinedRoom -> List Username
+roomTypingUsers jr = Maybe.withDefault []
+    <| Maybe.andThen (Result.toMaybe << Decode.decodeValue (Decode.field "user_ids" (list string)))
+    <| Maybe.map .content
+    <| Maybe.andThen (findLast (((==) "m.typing") << .type_))
+    <| Maybe.andThen .events jr.ephemeral
+
 roomsUsers : SyncResponse -> List Username
 roomsUsers s =
     let

src/Scylla/Views.elm

@@ -86,6 +86,13 @@ joinedRoomView m roomId jr =
         events = Maybe.withDefault [] <| Maybe.andThen .events jr.timeline
         renderedEvents = List.filterMap (eventView m) events
         eventWrapper = eventWrapperView m renderedEvents
+        typing = List.map (displayName m) <| roomTypingUsers jr
+        typingText = String.join ", " typing
+        typingSuffix = case List.length typing of
+            0 -> ""
+            1 -> " is typing..."
+            _ -> " are typing..."
+        typingWrapper = div [ class "typing-wrapper" ] [ text <| typingText ++ typingSuffix ] 
         messageInput = div [ class "message-wrapper" ]
             [ input
                 [ type_ "text"
@@ -98,6 +105,7 @@ joinedRoomView m roomId jr =
         div [ class "room-wrapper" ]
             [ h2 [] [ text <| Maybe.withDefault "<No Name>" <| roomName jr ]
             , eventWrapper
+            , typingWrapper
             , messageInput
             ]