{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE StandaloneDeriving #-}
{-# LANGUAGE RecordWildCards #-}
--------------------------------------------------------------------------------
module Xanthous.Entities.Item
( Item(..)
, itemType
, density
, volume
, newWithType
, isEdible
, weight
) where
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import Xanthous.Prelude
import Test.QuickCheck (Arbitrary, CoArbitrary, Function)
import Data.Aeson (ToJSON, FromJSON)
import Data.Aeson.Generic.DerivingVia
import Control.Monad.Random (MonadRandom)
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import Xanthous.Entities.RawTypes (ItemType)
import qualified Xanthous.Entities.RawTypes as Raw
import Xanthous.Game.State
import Xanthous.Data (Grams, Per, Cubic, Meters, (|*|))
import Xanthous.Util.QuickCheck (GenericArbitrary(GenericArbitrary))
import Xanthous.Random (choose, FiniteInterval(..))
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data Item = Item
{ _itemType :: ItemType
, _density :: Grams `Per` Cubic Meters
, _volume :: Cubic Meters
}
deriving stock (Eq, Show, Ord, Generic)
deriving anyclass (NFData, CoArbitrary, Function)
deriving Draw via DrawRawChar "_itemType" Item
deriving Arbitrary via GenericArbitrary Item
deriving (ToJSON, FromJSON)
via WithOptions '[ FieldLabelModifier '[Drop 1] ]
Item
makeLenses ''Item
-- deriving via (Brainless Item) instance Brain Item
instance Brain Item where step = brainVia Brainless
instance Entity Item where
description = view $ itemType . Raw.description
entityChar = view $ itemType . Raw.char
entityCollision = const Nothing
newWithType :: MonadRandom m => ItemType -> m Item
newWithType _itemType = do
_density <- choose . FiniteInterval $ _itemType ^. Raw.density
_volume <- choose . FiniteInterval $ _itemType ^. Raw.volume
pure Item {..}
isEdible :: Item -> Bool
isEdible = Raw.isEdible . view itemType
-- | The weight of this item, calculated by multiplying its volume by the
-- density of its material
weight :: Item -> Grams
weight item = (item ^. density) |*| (item ^. volume)
