Fix setting ui theme for anonymous

modules/webapp/src/main/elm/App/Data.elm

@@ -11,6 +11,7 @@ import Browser exposing (UrlRequest)
 import Browser.Navigation exposing (Key)
 import Data.Flags exposing (Flags)
 import Data.UiSettings exposing (UiSettings)
+import Data.UiTheme exposing (UiTheme)
 import Http
 import Page exposing (Page(..))
 import Page.CollectiveSettings.Data
@@ -46,6 +47,7 @@ type alias Model =
     , subs : Sub Msg
     , uiSettings : UiSettings
     , sidebarVisible : Bool
+    , anonymousTheme : UiTheme
     }
 
 
@@ -94,6 +96,7 @@ init key url flags_ settings =
       , subs = Sub.none
       , uiSettings = settings
       , sidebarVisible = settings.sideMenuVisible
+      , anonymousTheme = Data.UiTheme.Light
       }
     , Cmd.batch
         [ Cmd.map UserSettingsMsg uc

modules/webapp/src/main/elm/App/Update.elm

@@ -52,18 +52,18 @@ updateWithSub msg model =
             ( { model | sidebarVisible = not model.sidebarVisible }, Cmd.none, Sub.none )
 
         ToggleDarkMode ->
-            let
-                settings =
-                    model.uiSettings
-
-                next =
-                    Data.UiTheme.cycle settings.uiTheme
-
-                newSettings =
-                    { settings | uiTheme = next }
-            in
             case model.flags.account of
                 Just _ ->
+                    let
+                        settings =
+                            model.uiSettings
+
+                        next =
+                            Data.UiTheme.cycle settings.uiTheme
+
+                        newSettings =
+                            { settings | uiTheme = next }
+                    in
                     -- when authenticated, store it in settings only
                     -- once new settings arrive via a subscription,
                     -- the ui is updated. so it is also updated on
@@ -74,8 +74,12 @@ updateWithSub msg model =
                     )
 
                 Nothing ->
+                    let
+                        next =
+                            Data.UiTheme.cycle model.anonymousTheme
+                    in
                     -- when not logged in, simply set the theme
-                    ( { model | userMenuOpen = False }
+                    ( { model | userMenuOpen = False, anonymousTheme = next }
                     , Ports.setUiTheme next
                     , Sub.none
                     )