feat(gs/xanthous): Allow generating creatures with items r/3097

Add an `equippedItems` field to the CreatureType raw, which provides a
chance for generating that creature with an item equipped, which goes
into a new `inventory` field on the creature entity itself. Currently
the creature doesn't actually *use* this equipped item, but it's a step.

This commit also adds a broken-dagger equipped 90% of the time to the
"husk" creature.

Change-Id: I6416c0678ba7bc1b002c5ce6119f7dc97dd86437

1 files changed, 6 insertions, 1 deletions

diff --git a/users/grfn/xanthous/src/Xanthous/Entities/Common.hs b/users/grfn/xanthous/src/Xanthous/Entities/Common.hs
index 1444f3ce1639..becd1b1ef62e 100644
--- a/users/grfn/xanthous/src/Xanthous/Entities/Common.hs
+++ b/users/grfn/xanthous/src/Xanthous/Entities/Common.hs
@@ -8,6 +8,7 @@
 module Xanthous.Entities.Common
   ( -- * Inventory
     Inventory(..)
+  , HasInventory(..)
   , backpack
   , wielded
   , items
@@ -191,6 +192,10 @@ instance Semigroup Inventory where
 instance Monoid Inventory where
   mempty = Inventory mempty $ Hands Nothing Nothing
 
+class HasInventory s a | s -> a where
+  inventory :: Lens' s a
+  {-# MINIMAL inventory #-}
+
 -- | Representation for where in the inventory an item might be
 data InventoryPosition
   = Backpack
@@ -224,7 +229,7 @@ itemsWithPosition :: Fold Inventory (InventoryPosition, Item)
 itemsWithPosition = folding $ (<>) <$> backpackItems <*> handItems
   where
     backpackItems = toListOf $ backpack . folded . to (Backpack ,)
-    handItems inventory = case inventory ^. wielded of
+    handItems inv = case inv ^. wielded of
        DoubleHanded i -> pure (BothHands, i ^. wieldedItem)
        Hands l r -> (l ^.. folded . wieldedItem . to (LeftHand ,))
                  <> (r ^.. folded . wieldedItem . to (RightHand ,))