Move selection list offset into option screen data structure

src/Dodge/Data/SelectionList.hs

@@ -10,7 +10,6 @@ import Dodge.Data.CardinalPoint
 data SelectionList = SelectionList
     { _slPosX :: Float
     , _slPosY :: Float
-    , _slOffset :: Int
     , _slScale :: Float
     , _slVerticalGap :: Float
     , _slItems :: [SelectionItem]

src/Dodge/Data/Universe.hs

@@ -52,6 +52,7 @@ data ScreenLayer
     = OptionScreen
         { _scTitle :: String
         , _scOptions :: [MenuOption]
+        , _scOffset :: Int
         , _scMaybeOption :: Maybe MenuOption
         , _scOptionFlag :: OptionScreenFlag
         , _scSelectionList :: SelectionList

src/Dodge/Menu/Option.hs

@@ -16,6 +16,7 @@ slTitleOptionsEff title ops defstr eff u =
     OptionScreen
         { _scTitle = title
         , _scOptions = ops
+        , _scOffset = 0
         , _scMaybeOption = fmap (Toggle eff . const . MODString) defstr
         , _scOptionFlag = NormalOptions
         , _scSelectionList = makeOptionsSelectionList (Just 0) u ops
@@ -35,7 +36,6 @@ makeOptionsSelectionList :: Maybe Int -> Universe -> [MenuOption] -> SelectionLi
 makeOptionsSelectionList mselpos u mos = SelectionList
     { _slPosX = 50
     , _slPosY = 50
-    , _slOffset = 0
     , _slScale = 2
     , _slVerticalGap = 30
     , _slItems = optionsToSelections u mos

src/Dodge/Render/HUD.hs

@@ -55,7 +55,6 @@ defaultSelectionList = SelectionList
     , _slScale = 1
     , _slPosX = 0
     , _slPosY = 0
-    , _slOffset = 0
     , _slItems = []
     , _slShownItems = []
     , _slSelPos = Nothing
@@ -71,7 +70,6 @@ subInvSelectionList = SelectionList
     , _slScale = 1
     , _slPosX = subInvX
     , _slPosY = 60
-    , _slOffset = 0
     , _slItems = []
     , _slShownItems = []
     , _slSelPos = Nothing

src/Dodge/SelectionList.hs

@@ -1,11 +1,17 @@
 module Dodge.SelectionList where
 
 --import Color
-import Dodge.Data.SelectionList
+import Dodge.Data.Universe
 import LensHelp
+import Data.Maybe
 
-setShownSelectionItems :: SelectionList -> SelectionList
+setShownSelectionItems :: ScreenLayer -> ScreenLayer
-setShownSelectionItems sl = case sl ^? slSizeRestriction of
+setShownSelectionItems sl = fromMaybe sl $ do
+    offset <- sl ^? scOffset
+    return $ sl & scSelectionList %~ setShownSelectionItems' offset
+
+setShownSelectionItems' :: Int -> SelectionList -> SelectionList
+setShownSelectionItems' offset sl = case sl ^? slSizeRestriction of
     Just (SelectionSizeRestriction maxlines _ botit _)
         | length allitems > maxlines -> 
             sl & slShownItems .~ take (maxlines - 2) (drop offset allitems) -- ++ repeat dummyitem))
@@ -13,5 +19,4 @@ setShownSelectionItems sl = case sl ^? slSizeRestriction of
     _ -> sl & slShownItems .~ allitems
   where
 --    dummyitem = (SelectionItem [] 1 False 0 white 0, DummySelectionItem)
-    offset = sl ^. slOffset
     allitems = zipWith (\x y -> (x,ListedSelectionItem y)) (sl ^. slItems) [0..]

src/Dodge/TestString.hs

@@ -8,7 +8,7 @@ import qualified Data.Map.Strict as M
 
 testStringInit :: Universe -> [String]
 testStringInit u =
-    [ show $ u ^? uvScreenLayers . _head . scSelectionList . slOffset
+    [ show $ u ^? uvScreenLayers . _head . scOffset
     ]
     ++ [  shortShow $ u ^?! uvWorld . cWorld . lWorld . creatures . ix 0 . crPos
     ] 

src/Dodge/Update.hs

@@ -103,7 +103,7 @@ mouseClickOptionsList mos sl u = case u ^. uvWorld . input . mouseButtons . at B
             ScrollSelectionItem -> do
                 maxlines <- sl ^? slSizeRestriction . maxSelectionLines
                 alllines <- sl ^? slLength
-                Just $ uvScreenLayers . _head . scSelectionList . slOffset %~ 
+                Just $ uvScreenLayers . _head . scOffset %~ 
                     (\x -> if x + maxlines - 2 >= alllines then 0 else x + maxlines - 2)
             SpecialSelectionItem -> Just id
     _ -> u
@@ -155,7 +155,7 @@ optionScreenUpdate mos mop _ sl u =
     . mouseOverSelectionList sl
     . menuWheelEvents
     . over (uvScreenLayers . _head . scSelectionList) (setSelectionListRestriction cfig)
-    $ over (uvScreenLayers . _head . scSelectionList) setShownSelectionItems
+    $ over (uvScreenLayers . _head) setShownSelectionItems
     u
   where
     cfig = u ^. uvConfig