Allow equipment on both wrists

src/Dodge/Creature/Impulse/UseItem.hs

@@ -41,49 +41,54 @@ itemEffect cr it w = case it ^? itUse of
     setuhamdown = creatures . ix (_crID cr) . crHammerPosition .~ HammerDown
 
 toggleEquipmentAt :: Int -> Item -> Creature -> Creature
-toggleEquipmentAt invid itm cr 
-    | invid `IM.member` _crInvEquipped cr = cr & crInvEquipped . at invid .~ Nothing
-        & removeEquipmentUsingSite esite
-        & setEquipmentSite esite Nothing'
-    | otherwise = cr & crInvEquipped . at invid .~ Just epos
-        & removeEquipmentUsingSite esite
-        & setEquipmentSite esite (Just' invid)
+toggleEquipmentAt invid itm cr = case cr ^? crInvEquipped . ix invid of
+    Just epos -> cr & crInvEquipped . at invid .~ Nothing
+        & crEquipment . at epos .~ Nothing
+    Nothing -> equipUsingSite invid itm cr
+
+equipUsingSite :: Int -> Item -> Creature -> Creature
+equipUsingSite invid itm cr = cr
+    & crInvEquipped . at invid .~ Just epos
+    & crEquipment . at epos .~ Just invid
+    & removeOtherEquipment
   where
-    esite = _eqSite (_itUse itm)
-    epos = eqSiteToPos cr esite
-    f Nothing = Just ()
-    f (Just ()) = Nothing
+    epos = eqSiteToPos cr (_eqSite $ _itUse itm)
+    removeOtherEquipment = case cr ^? crEquipment . ix epos of
+        Nothing -> id
+        Just oid -> crInvEquipped . at oid .~ Nothing
 
 eqSiteToPos :: Creature -> EquipSite -> EquipPosition
 eqSiteToPos cr es = case es of
     GoesOnHead      -> OnHead
     GoesOnChest     -> OnChest
     GoesOnBack      -> OnBack
-    GoesOnWrist     -> OnLeftWrist
     GoesOnLegs      -> OnLegs
     GoesOnSpecial   -> OnSpecial
+    GoesOnWrist     -> case cr ^? crEquipment . ix OnLeftWrist of
+        Nothing -> OnLeftWrist
+        _ -> OnRightWrist
 
 removeEquipmentUsingSite :: EquipSite -> Creature -> Creature
 removeEquipmentUsingSite esite cr = case esite of
     GoesOnSpecial   -> cr
-    _ -> case cr ^? crEquipment . esiteToPoint . _Just' of
+    _ -> case cr ^? crEquipment . esiteToPoint of
         Just invid -> cr & crInvEquipped . at invid .~ Nothing
         _ -> cr
   where
     esiteToPoint = case esite of
-        GoesOnHead      -> onHead
-        GoesOnChest     -> onChest
-        GoesOnBack      -> onBack
-        GoesOnWrist     -> onWristL
-        GoesOnLegs      -> onLegs
+        GoesOnHead      -> ix OnHead
+        GoesOnChest     -> ix OnChest
+        GoesOnBack      -> ix OnBack
+        GoesOnWrist     -> ix OnLeftWrist
+        GoesOnLegs      -> ix OnLegs
 
-setEquipmentSite :: EquipSite -> Maybe' Int -> Creature -> Creature
+setEquipmentSite :: EquipSite -> Maybe Int -> Creature -> Creature
 setEquipmentSite esite = case esite of
-    GoesOnHead      -> set (crEquipment . onHead)
-    GoesOnChest     -> set (crEquipment . onChest)
-    GoesOnBack      -> set (crEquipment . onBack)
-    GoesOnWrist     -> set (crEquipment . onWristL)
-    GoesOnLegs      -> set (crEquipment . onLegs)
+    GoesOnHead      -> set (crEquipment . at OnHead)
+    GoesOnChest     -> set (crEquipment . at OnChest)
+    GoesOnBack      -> set (crEquipment . at OnBack)
+    GoesOnWrist     -> set (crEquipment . at OnLeftWrist)
+    GoesOnLegs      -> set (crEquipment . at OnLegs)
     GoesOnSpecial   -> const id
 
 useLeftItem :: Int -> World -> World