use Context.pref to honor anon prefs in RoundApi - closes lichess-org#14686

Author: ornicar

modules/api/src/main/RoundApi.scala

@@ -46,7 +46,7 @@ final private[api] class RoundApi(
     for
       initialFen <- gameRepo.initialFen(pov.game)
       users      <- users.orLoad(userApi.gamePlayers(pov.game.userIdPair, pov.game.perfType))
-      prefs      <- prefApi.get(users.map(_.map(_.user)))
+      prefs      <- prefApi.get(users.map(_.map(_.user)), pov.color, ctx.pref)
       given Lang = ctx.lang
       (((((json, simul), swiss), note), forecast), bookmarked) <-
         jsonView.playerJson(pov, prefs, users, initialFen, ctxFlags) zip

modules/pref/src/main/PrefApi.scala

@@ -6,7 +6,7 @@ import reactivemongo.api.bson.*
 import lila.db.dsl.{ given, * }
 import lila.memo.CacheApi.*
 import lila.user.User
-import chess.ByColor
+import chess.{ Color, ByColor }
 
 final class PrefApi(
     val coll: Coll,
@@ -58,8 +58,9 @@ final class PrefApi(
   def byId(both: ByColor[Option[UserId]]): Fu[ByColor[Pref]] =
     both.traverse(_.fold(fuccess(Pref.default))(byId))
 
-  def get(both: ByColor[Option[User]]): Fu[ByColor[Pref]] =
-    both.traverse(_.fold(fuccess(Pref.default))(get))
+  def get(both: ByColor[Option[User]], myPov: Color, myPref: Pref): Fu[ByColor[Pref]] =
+    both(!myPov).so(get) map: opponent =>
+      myPov.fold(ByColor(myPref, opponent), ByColor(opponent, myPref))
 
   def followable(userId: UserId): Fu[Boolean] =
     coll.primitiveOne[Boolean]($id(userId), "follow").map(_ | Pref.default.follow)