feat(xanthous): Track the volume and density of item types

Allow the itemType raw to have density and volume fields, both of which
represent *intervals* of both density and volume (because both can
hypothetically vary a bit). The idea here is that when we're making
an *instance* of one of these items, we pick a random value in the
range.

Lots of stuff in this commit is datatype and typeclass instances to
support things like intervals being fields on datatypes that get
serialized to saved games - including a manual definition of Ord for
Item since Ord isn't well-defined for intervals

Change-Id: Ia088f2f75cdce9d00560297e5c269e3310b85bc3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/3225
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI

users/grfn/xanthous/src/Xanthous/Entities/RawTypes.hs

@@ -51,11 +51,12 @@ import Data.Aeson.Generic.DerivingVia
 import Data.Aeson (ToJSON, FromJSON)
 --------------------------------------------------------------------------------
 import Xanthous.Messages (Message(..))
-import Xanthous.Data (TicksPerTile, Hitpoints)
+import Xanthous.Data (TicksPerTile, Hitpoints, Per, Grams, Cubic, Meters)
 import Xanthous.Data.EntityChar
 import Xanthous.Util.QuickCheck
 import Xanthous.Generators.Speech (Language, gormlak, english)
 import Xanthous.Orphans ()
+import Data.Interval (Interval, lowerBound', upperBound')
 --------------------------------------------------------------------------------
 
 -- | Identifiers for languages that creatures can speak.
@@ -153,10 +154,12 @@ data ItemType = ItemType
   , _description     :: !Text
   , _longDescription :: !Text
   , _char            :: !EntityChar
+  , _density         :: !(Interval (Grams `Per` Cubic Meters))
+  , _volume          :: !(Interval (Cubic Meters))
   , _edible          :: !(Maybe EdibleItem)
   , _wieldable       :: !(Maybe WieldableItem)
   }
-  deriving stock (Show, Eq, Ord, Generic)
+  deriving stock (Show, Eq, Generic)
   deriving anyclass (NFData, CoArbitrary, Function)
   deriving Arbitrary via GenericArbitrary ItemType
   deriving (ToJSON, FromJSON)
@@ -164,6 +167,20 @@ data ItemType = ItemType
                        ItemType
 makeFieldsNoPrefix ''ItemType
 
+instance Ord ItemType where
+  compare x y
+    = compareOf name x y
+    <> compareOf description x y
+    <> compareOf longDescription x y
+    <> compareOf char x y
+    <> compareOf (density . to extractInterval) x y
+    <> compareOf (volume . to extractInterval) x y
+    <> compareOf edible x y
+    <> compareOf wieldable x y
+    where
+      compareOf l = comparing (view l)
+      extractInterval = lowerBound' &&& upperBound'
+
 -- | Can this item be eaten?
 isEdible :: ItemType -> Bool
 isEdible = has $ edible . _Just

users/grfn/xanthous/src/Xanthous/Entities/Raws/noodles.yaml

@@ -10,3 +10,5 @@ Item:
     hitpointsHealed: 2
     eatMessage:
       - You slurp up the noodles. Yumm!
+  density: 500000
+  volume: 0.001

users/grfn/xanthous/src/Xanthous/Entities/Raws/stick.yaml

@@ -12,3 +12,7 @@ Item:
       - You bonk the {{creature.creatureType.name}} over the head with your stick.
       - You bash the {{creature.creatureType.name}} on the noggin with your stick.
       - You whack the {{creature.creatureType.name}} with your stick.
+  # https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/wood-density
+  # it's a hard stick. so it's dense wood.
+  density: 890000 # g/m³
+  volume: [ 0.003, 0.006 ] # ≈3.5 cm radius × ≈1m length