From fb5977dfd571661dbbb579dbee5b150e5dfab72f Mon Sep 17 00:00:00 2001
From: Gareth Latty <gareth@lattyware.co.uk>
Date: Sat, 12 Dec 2015 18:37:24 +0000
Subject: [PATCH] Added catch-up events to mitigate missing events from before
 the client joined.

---
 client/src/MassiveDecks/Actions/Action.elm    | 16 +++++++++++++---
 client/src/MassiveDecks/Actions/Event.elm     | 15 +++++++++++++++
 client/src/MassiveDecks/States/Playing/UI.elm |  2 ++
 client/src/MassiveDecks/States/Start.elm      |  5 +++--
 4 files changed, 33 insertions(+), 5 deletions(-)

diff --git a/client/src/MassiveDecks/Actions/Action.elm b/client/src/MassiveDecks/Actions/Action.elm
index 00b48d7..8d495c9 100644
--- a/client/src/MassiveDecks/Actions/Action.elm
+++ b/client/src/MassiveDecks/Actions/Action.elm
@@ -6,7 +6,7 @@ import Effects
 import MassiveDecks.Models.State exposing (InitialState)
 import MassiveDecks.Models.Game exposing (Lobby, LobbyAndHand)
 import MassiveDecks.Models.Player as Player
-import MassiveDecks.Actions.Event exposing (Event, events)
+import MassiveDecks.Actions.Event exposing (Event, events, catchUpEvents)
 
 
 type APICall a
@@ -37,8 +37,18 @@ type Action
 
 
 eventEffects : Lobby -> Lobby -> Effects.Effects Action
-eventEffects oldLobby newLobby
-  = events oldLobby newLobby
+eventEffects oldLobby newLobby =
+  events oldLobby newLobby |> eventsToEffects
+
+
+catchUpEffects : Lobby -> Effects.Effects Action
+catchUpEffects lobby =
+  catchUpEvents lobby |> eventsToEffects
+
+
+eventsToEffects : List Event -> Effects.Effects Action
+eventsToEffects events
+  = events
   |> List.map GameEvent
   |> List.map Task.succeed
   |> List.map Effects.task
diff --git a/client/src/MassiveDecks/Actions/Event.elm b/client/src/MassiveDecks/Actions/Event.elm
index d6a5da4..c9eea27 100644
--- a/client/src/MassiveDecks/Actions/Event.elm
+++ b/client/src/MassiveDecks/Actions/Event.elm
@@ -23,6 +23,18 @@ events oldLobby newLobby = List.concat
   ]
 
 
+{-| Generate events when joining an in-progress lobby to catch up. -}
+catchUpEvents : Lobby -> List Event
+catchUpEvents lobby =
+  case lobby.round of
+    Just round ->
+      case round.responses of
+        Hidden count -> [ roundPlayed count ]
+        Revealed _ -> []
+    Nothing ->
+      []
+
+
 diffPlayers : List Player -> List Player -> List Event
 diffPlayers oldPlayers newPlayers =
   List.concatMap (diffPlayer oldPlayers) newPlayers
@@ -53,6 +65,9 @@ diffRound oldRound newRound =
       List.filterMap identity
         [ Maybe.map roundEnd oldRound
         , Maybe.map roundStart newRound
+        , newRound `Maybe.andThen` (\newRound -> case newRound.responses of
+            Hidden count -> Just (roundPlayed count)
+            Revealed _ -> Nothing)
         ]
     else
       Maybe.map2 changedRound oldRound newRound |> Maybe.withDefault []
diff --git a/client/src/MassiveDecks/States/Playing/UI.elm b/client/src/MassiveDecks/States/Playing/UI.elm
index e1cd57e..3932c27 100644
--- a/client/src/MassiveDecks/States/Playing/UI.elm
+++ b/client/src/MassiveDecks/States/Playing/UI.elm
@@ -68,6 +68,7 @@ roundContents address data round =
       ]
     ]
 
+
 consideringView : Signal.Address Action -> Int -> List Response -> Bool -> Html
 consideringView address considering consideringCards isCzar =
   let
@@ -76,6 +77,7 @@ consideringView address considering consideringCards isCzar =
     ol [ class "considering" ]
       (List.append (List.map (\card -> li [] [ (playedResponse card) ]) consideringCards) extra)
 
+
 winnerContentsAndHeader : Signal.Address Action -> FinishedRound -> List Player -> (List Html, List Html)
 winnerContentsAndHeader address round players =
   let
diff --git a/client/src/MassiveDecks/States/Start.elm b/client/src/MassiveDecks/States/Start.elm
index 3ce4a28..6220fea 100644
--- a/client/src/MassiveDecks/States/Start.elm
+++ b/client/src/MassiveDecks/States/Start.elm
@@ -7,7 +7,7 @@ import Html exposing (Html)
 
 import MassiveDecks.API as API
 import MassiveDecks.Models.State exposing (Model, State(..))
-import MassiveDecks.Actions.Action exposing (Action(..), APICall(..))
+import MassiveDecks.Actions.Action exposing (Action(..), APICall(..), catchUpEffects)
 import MassiveDecks.Models.State exposing (State(..), StartData, PlayingData, Error, Global)
 import MassiveDecks.States.Start.UI as UI
 import MassiveDecks.States.Config as Config
@@ -47,7 +47,8 @@ update action global data = case action of
     case lobbyAndHand.lobby.round of
       Just _ ->
         (Playing.modelSub global lobbyId secret
-          (PlayingData lobbyAndHand.lobby lobbyAndHand.hand secret [] Nothing Nothing []), Effects.none)
+          (PlayingData lobbyAndHand.lobby lobbyAndHand.hand secret [] Nothing Nothing []),
+            catchUpEffects lobbyAndHand.lobby)
 
       Nothing ->
         (Config.modelSub global lobbyId secret