Make inventory cursor change when dropping items sensible

src/Dodge/SelectionSections.hs

@@ -1,5 +1,6 @@
 module Dodge.SelectionSections (
     scrollSelectionSections,
+    nextInSectionSS,
     ssLookupDown,
     ssLookupGT,
     ssSetCursor,
@@ -35,6 +36,12 @@ scrollSelectionSections yi sss msel
     | yi > 0 = foldl' (&) msel $ replicate yi (ssScrollUsing ssLookupUp sss)
     | otherwise = foldl' (&) msel $ replicate (negate yi) (ssScrollUsing ssLookupDown sss)
 
+nextInSectionSS :: 
+    IM.IntMap (SelectionSection a) ->
+    Maybe (Int, Int) ->
+    Maybe (Int, Int)
+nextInSectionSS sss = ssScrollUsing ssLookupNextMax sss
+
 --setFirstPosSelectionSections :: SelectionSections a -> SelectionSections a
 --setFirstPosSelectionSections sss = fromMaybe sss $ do
 --    (i, j, _) <- ssLookupMin sss
@@ -93,6 +100,22 @@ ssLookupDown i j sss = case ssLookupGT i j sss of
     Nothing -> ssLookupMin sss
     x -> x
 
+ssLookupNextMax ::
+    Int ->
+    Int ->
+    IM.IntMap (SelectionSection a) ->
+    Maybe (Int, Int, SelectionItem a)
+ssLookupNextMax i j sss = case ssLookupGT i j sss of
+    Just x@(i',j',_) | i' == i && j' > j -> Just x
+    _ -> ssLookupMaxInSection i sss <|> ssLookupDown i j sss
+
+ssLookupMaxInSection :: Int -> IM.IntMap (SelectionSection a) ->
+    Maybe (Int, Int, SelectionItem a)
+ssLookupMaxInSection i sss = do
+    ss <- sss ^? ix i . ssItems
+    (j,s) <- IM.lookupMax ss
+    return (i,j,s)
+
 ssLookupLT ::
     Int ->
     Int ->