Tweak inventory manipulation

src/Dodge/Update/Input/InGame.hs

@@ -144,7 +144,7 @@ doDrag cfig n k mmouseover w = fromMaybe w $ do
     guard (n /= 0)
     ss <- w ^? hud . diSections . ix k . ssItems
     x <- mmouseover
-    is <- w ^? hud . diSelection . _Just . slSet
+    is <- selectionSet w
     return $
         if concurrentIS is
             then shiftInvItems cfig n k x is ss w
@@ -154,15 +154,24 @@ tryDropSelected :: Maybe (Int, Int) -> World -> Maybe World
 tryDropSelected mpos w = do
     guard $ maybe True (\(i, _) -> i == 3) mpos
     cr <- w ^? cWorld . lWorld . creatures . ix 0
-    Sel 0 _ xs <- w ^? hud . diSelection . _Just
-    return . foldl' (flip $ dropItem cr) w . IS.toDescList $ xs
+    0 <- w ^? hud . diSelection . _Just . slSec
+    xs <- selectionSet w
+    return 
+        . (hud . diSelection ?~ Sel 3 0 (IS.fromDistinctAscList [0..IS.size xs - 1]))
+        . foldl' (flip $ dropItem cr) w . IS.toDescList $ xs
+
+selectionSet :: World -> Maybe IS.IntSet
+selectionSet w = case w ^? hud . diSelection . _Just . slSet of
+        Just is' | not $ IS.null is' -> Just is'
+        _ -> IS.singleton <$> w ^? hud . diSelection . _Just . slInt
+
 
 tryPickupSelected :: Int -> Maybe (Int, Int) -> World -> Maybe World
 tryPickupSelected k mpos w = do
     guard $ k == 3
     guard $ maybe True (\(i, _) -> i == 0 || i == 1) mpos
     cr <- w ^? cWorld . lWorld . creatures . ix 0
-    xs <- w ^? hud . diSelection . _Just . slSet
+    xs <- selectionSet w
     let nfreeslots = crNumFreeSlots (w ^. cWorld . lWorld . items) cr
         itmstopickup = mapMaybe g $ IS.toList xs
         slotsneeded = alaf Sum foldMap itInvHeight itmstopickup
@@ -299,7 +308,8 @@ endCombineRegex w = ssSetCursor (ssLookupDown 0 j) sss
 startDrag :: (Int, Int) -> World -> World
 startDrag (a, b) w = setcontext $ case w ^? hud . diSelection . _Just of
     Just (Sel i _ xs) | i == a && b `IS.member` xs -> w
-    _ -> invSetSelection (Sel a b (IS.singleton b)) w
+--    _ -> invSetSelection (Sel a b (IS.singleton b)) w
+    _ -> invSetSelection (Sel a b mempty) w
   where
     setcontext = input . mouseContext .~ OverInvDrag a (Just (a, b))