feature: long press to save original illust

Pixiview.iOS/Services/EnvironmentService.cs

@@ -29,29 +29,28 @@ namespace Pixiview.iOS.Services
         #region - Theme -
 
         [SuppressMessage("Code Notifications", "XI0002:Notifies you from using newer Apple APIs when targeting an older OS version", Justification = "<Pending>")]
-        public Theme GetApplicationTheme()
+        public OSAppTheme GetApplicationTheme()
         {
             if (UIDevice.CurrentDevice.CheckSystemVersion(12, 0))
             {
                 var currentController = Platform.GetCurrentUIViewController();
                 if (currentController == null)
                 {
-                    return Theme.Light;
+                    return OSAppTheme.Unspecified;
                 }
+
                 var style = currentController.TraitCollection.UserInterfaceStyle;
                 if (style == UIUserInterfaceStyle.Dark)
                 {
-                    return Theme.Dark;
+                    return OSAppTheme.Dark;
                 }
-                else
+                else if (style == UIUserInterfaceStyle.Light)
                 {
-                    return Theme.Light;
+                    return OSAppTheme.Light;
                 }
             }
-            else
-            {
-                return Theme.Light;
-            }
+
+            return OSAppTheme.Unspecified;
         }
 
         public void SetStatusBarStyle(StatusBarStyles style)