Add 'users/glittershark/xanthous/' from commit '53b56744f4335c038724a1bcffc27a7eb8cf6a6d' r/978

git-subtree-dir: users/glittershark/xanthous
git-subtree-mainline: 91f53f02d8479303910abfd3f3690d3ef27e6c4b
git-subtree-split: 53b56744f4335c038724a1bcffc27a7eb8cf6a6d

1 files changed, 558 insertions, 0 deletions

diff --git a/users/glittershark/xanthous/src/Xanthous/Game/State.hs b/users/glittershark/xanthous/src/Xanthous/Game/State.hs
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+{-# LANGUAGE StandaloneDeriving   #-}
+{-# LANGUAGE RecordWildCards      #-}
+{-# LANGUAGE UndecidableInstances #-}
+{-# LANGUAGE TemplateHaskell      #-}
+{-# LANGUAGE GADTs                #-}
+{-# LANGUAGE AllowAmbiguousTypes  #-}
+--------------------------------------------------------------------------------
+module Xanthous.Game.State
+  ( GameState(..)
+  , entities
+  , levels
+  , revealedPositions
+  , messageHistory
+  , randomGen
+  , activePanel
+  , promptState
+  , characterEntityID
+  , autocommand
+  , GamePromptState(..)
+
+    -- * Game Level
+  , GameLevel(..)
+  , levelEntities
+  , upStaircasePosition
+  , levelRevealedPositions
+
+    -- * Messages
+  , MessageHistory(..)
+  , HasMessages(..)
+  , HasTurn(..)
+  , HasDisplayedTurn(..)
+  , pushMessage
+  , previousMessage
+  , nextTurn
+
+    -- * Autocommands
+  , Autocommand(..)
+  , AutocommandState(..)
+  , _NoAutocommand
+  , _ActiveAutocommand
+
+    -- * App monad
+  , AppT(..)
+  , AppM
+  , runAppT
+
+    -- * Entities
+  , Draw(..)
+  , Brain(..)
+  , Brainless(..)
+  , brainVia
+  , Collision(..)
+  , Entity(..)
+  , SomeEntity(..)
+  , downcastEntity
+  , _SomeEntity
+  , entityIs
+    -- ** Vias
+  , Color(..)
+  , DrawNothing(..)
+  , DrawRawChar(..)
+  , DrawRawCharPriority(..)
+  , DrawCharacter(..)
+  , DrawStyledCharacter(..)
+  , DeriveEntity(..)
+    -- ** Field classes
+  , HasChar(..)
+  , HasStyle(..)
+
+    -- * Debug State
+  , DebugState(..)
+  , debugState
+  , allRevealed
+  ) where
+--------------------------------------------------------------------------------
+import           Xanthous.Prelude
+--------------------------------------------------------------------------------
+import           Data.List.NonEmpty ( NonEmpty((:|)))
+import qualified Data.List.NonEmpty as NonEmpty
+import           Data.Typeable
+import           Data.Coerce
+import           System.Random
+import           Test.QuickCheck
+import           Test.QuickCheck.Arbitrary.Generic
+import           Control.Monad.Random.Class
+import           Control.Monad.State
+import           Control.Monad.Trans.Control (MonadTransControl(..))
+import           Control.Monad.Trans.Compose
+import           Control.Monad.Morph (MFunctor(..))
+import           Brick (EventM, Widget, raw, str, emptyWidget)
+import           Data.Aeson (ToJSON(..), FromJSON(..), Value(Null))
+import qualified Data.Aeson as JSON
+import           Data.Aeson.Generic.DerivingVia
+import           Data.Generics.Product.Fields
+import qualified Graphics.Vty.Attributes as Vty
+import qualified Graphics.Vty.Image as Vty
+--------------------------------------------------------------------------------
+import           Xanthous.Util (KnownBool(..))
+import           Xanthous.Util.QuickCheck (GenericArbitrary(..))
+import           Xanthous.Data
+import           Xanthous.Data.App
+import           Xanthous.Data.Levels
+import           Xanthous.Data.EntityMap (EntityMap, EntityID)
+import           Xanthous.Data.EntityChar
+import           Xanthous.Data.VectorBag
+import           Xanthous.Data.Entities
+import           Xanthous.Orphans ()
+import           Xanthous.Game.Prompt
+import           Xanthous.Game.Env
+--------------------------------------------------------------------------------
+
+data MessageHistory
+  = MessageHistory
+  { _messages      :: Map Word (NonEmpty Text)
+  , _turn          :: Word
+  , _displayedTurn :: Maybe Word
+  }
+  deriving stock (Show, Eq, Generic)
+  deriving anyclass (NFData, CoArbitrary, Function)
+  deriving Arbitrary via GenericArbitrary MessageHistory
+  deriving (ToJSON, FromJSON)
+       via WithOptions '[ FieldLabelModifier '[Drop 1] ]
+           MessageHistory
+makeFieldsNoPrefix ''MessageHistory
+
+instance Semigroup MessageHistory where
+  (MessageHistory msgs₁ turn₁ dt₁) <> (MessageHistory msgs₂ turn₂ dt₂) =
+    MessageHistory (msgs₁ <> msgs₂) (max turn₁ turn₂) $ case (dt₁, dt₂) of
+      (_, Nothing)      -> Nothing
+      (Just t, _)       -> Just t
+      (Nothing, Just t) -> Just t
+
+instance Monoid MessageHistory where
+  mempty = MessageHistory mempty 0 Nothing
+
+type instance Element MessageHistory = [Text]
+instance MonoFunctor MessageHistory where
+  omap f mh@(MessageHistory _ t _) =
+    mh & messages . at t %~ (NonEmpty.nonEmpty . f . toList =<<)
+
+instance MonoComonad MessageHistory where
+  oextract (MessageHistory ms t dt) = maybe [] toList $ ms ^. at (fromMaybe t dt)
+  oextend cok mh@(MessageHistory _ t dt) =
+    mh & messages . at (fromMaybe t dt) .~ NonEmpty.nonEmpty (cok mh)
+
+pushMessage :: Text -> MessageHistory -> MessageHistory
+pushMessage msg mh@(MessageHistory _ turn' _) =
+  mh
+  & messages . at turn' %~ \case
+    Nothing -> Just $ msg :| mempty
+    Just msgs -> Just $ msg <| msgs
+  & displayedTurn .~ Nothing
+
+nextTurn :: MessageHistory -> MessageHistory
+nextTurn = (turn +~ 1) . (displayedTurn .~ Nothing)
+
+previousMessage :: MessageHistory -> MessageHistory
+previousMessage mh = mh & displayedTurn .~ maximumOf
+  (messages . ifolded . asIndex . filtered (< mh ^. turn))
+  mh
+
+
+--------------------------------------------------------------------------------
+
+data GamePromptState m where
+  NoPrompt :: GamePromptState m
+  WaitingPrompt :: Text -> Prompt m -> GamePromptState m
+  deriving stock (Show, Generic)
+  deriving anyclass (NFData)
+
+-- | Non-injective! We never try to serialize waiting prompts, since:
+--
+--  * they contain callback functions
+--  * we can't save the game when in a prompt anyway
+instance ToJSON (GamePromptState m) where
+  toJSON _ = Null
+
+-- | Always expects Null
+instance FromJSON (GamePromptState m) where
+  parseJSON Null = pure NoPrompt
+  parseJSON _ = fail "Invalid GamePromptState; expected null"
+
+instance CoArbitrary (GamePromptState m) where
+  coarbitrary NoPrompt = variant @Int 1
+  coarbitrary (WaitingPrompt txt _) = variant @Int 2 . coarbitrary txt
+
+instance Function (GamePromptState m) where
+  function = functionMap onlyNoPrompt (const NoPrompt)
+    where
+      onlyNoPrompt NoPrompt = ()
+      onlyNoPrompt (WaitingPrompt _ _) =
+        error "Can't handle prompts in Function!"
+
+--------------------------------------------------------------------------------
+
+newtype AppT m a
+  = AppT { unAppT :: ReaderT GameEnv (StateT GameState m) a }
+  deriving ( Functor
+           , Applicative
+           , Monad
+           , MonadState GameState
+           , MonadReader GameEnv
+           , MonadIO
+           )
+       via (ReaderT GameEnv (StateT GameState m))
+  deriving ( MonadTrans
+           , MFunctor
+           )
+       via (ReaderT GameEnv `ComposeT` StateT GameState)
+
+type AppM = AppT (EventM ResourceName)
+
+--------------------------------------------------------------------------------
+
+class Draw a where
+  drawWithNeighbors :: Neighbors (VectorBag SomeEntity) -> a -> Widget n
+  drawWithNeighbors = const draw
+
+  draw :: a -> Widget n
+  draw = drawWithNeighbors $ pure mempty
+
+  -- | higher priority gets drawn on top
+  drawPriority :: a -> Word
+  drawPriority = const minBound
+
+instance Draw a => Draw (Positioned a) where
+  drawWithNeighbors ns (Positioned _ a) = drawWithNeighbors ns a
+  draw (Positioned _ a) = draw a
+
+newtype DrawCharacter (char :: Symbol) (a :: Type) where
+  DrawCharacter :: a -> DrawCharacter char a
+
+instance KnownSymbol char => Draw (DrawCharacter char a) where
+  draw _ = str $ symbolVal @char Proxy
+
+data Color = Black | Red | Green | Yellow | Blue | Magenta | Cyan | White
+
+class KnownColor (color :: Color) where
+  colorVal :: forall proxy. proxy color -> Vty.Color
+
+instance KnownColor 'Black where colorVal _ = Vty.black
+instance KnownColor 'Red where colorVal _ = Vty.red
+instance KnownColor 'Green where colorVal _ = Vty.green
+instance KnownColor 'Yellow where colorVal _ = Vty.yellow
+instance KnownColor 'Blue where colorVal _ = Vty.blue
+instance KnownColor 'Magenta where colorVal _ = Vty.magenta
+instance KnownColor 'Cyan where colorVal _ = Vty.cyan
+instance KnownColor 'White where colorVal _ = Vty.white
+
+class KnownMaybeColor (maybeColor :: Maybe Color) where
+  maybeColorVal :: forall proxy. proxy maybeColor -> Maybe Vty.Color
+
+instance KnownMaybeColor 'Nothing where maybeColorVal _ = Nothing
+instance KnownColor color => KnownMaybeColor ('Just color) where
+  maybeColorVal _ = Just $ colorVal @color Proxy
+
+newtype DrawStyledCharacter (fg :: Maybe Color) (bg :: Maybe Color) (char :: Symbol) (a :: Type) where
+  DrawStyledCharacter :: a -> DrawStyledCharacter fg bg char a
+
+instance
+  ( KnownMaybeColor fg
+  , KnownMaybeColor bg
+  , KnownSymbol char
+  )
+  => Draw (DrawStyledCharacter fg bg char a) where
+  draw _ = raw $ Vty.string attr $ symbolVal @char Proxy
+    where attr = Vty.Attr
+            { Vty.attrStyle = Vty.Default
+            , Vty.attrForeColor = maybe Vty.Default Vty.SetTo
+                                  $ maybeColorVal @fg Proxy
+            , Vty.attrBackColor = maybe Vty.Default Vty.SetTo
+                                  $ maybeColorVal @bg Proxy
+            , Vty.attrURL = Vty.Default
+            }
+
+instance Draw EntityChar where
+  draw EntityChar{..} = raw $ Vty.string _style [_char]
+
+--------------------------------------------------------------------------------
+
+newtype DrawNothing (a :: Type) = DrawNothing a
+
+instance Draw (DrawNothing a) where
+  draw = const emptyWidget
+  drawPriority = const 0
+
+newtype DrawRawChar (rawField :: Symbol) (a :: Type) = DrawRawChar a
+
+instance
+  forall rawField a raw.
+  ( HasField rawField a a raw raw
+  , HasChar raw EntityChar
+  ) => Draw (DrawRawChar rawField a) where
+  draw (DrawRawChar e) = draw $ e ^. field @rawField . char
+
+newtype DrawRawCharPriority
+  (rawField :: Symbol)
+  (priority :: Nat)
+  (a :: Type)
+  = DrawRawCharPriority a
+
+instance
+  forall rawField priority a raw.
+  ( HasField rawField a a raw raw
+  , KnownNat priority
+  , HasChar raw EntityChar
+  ) => Draw (DrawRawCharPriority rawField priority a) where
+  draw (DrawRawCharPriority e) = draw $ e ^. field @rawField . char
+  drawPriority = const . fromIntegral $ natVal @priority Proxy
+
+
+--------------------------------------------------------------------------------
+
+class Brain a where
+  step :: Ticks -> Positioned a -> AppM (Positioned a)
+  -- | Does this entity ever move on its own?
+  entityCanMove :: a -> Bool
+  entityCanMove = const False
+
+newtype Brainless a = Brainless a
+
+instance Brain (Brainless a) where
+  step = const pure
+
+-- | Workaround for the inability to use DerivingVia on Brain due to the lack of
+-- higher-order roles (specifically AppT not having its last type argument have
+-- role representational bc of StateT)
+brainVia
+  :: forall brain entity. (Coercible entity brain, Brain brain)
+  => (entity -> brain) -- ^ constructor, ignored
+  -> (Ticks -> Positioned entity -> AppM (Positioned entity))
+brainVia _ ticks = fmap coerce . step ticks . coerce @_ @(Positioned brain)
+
+--------------------------------------------------------------------------------
+
+class ( Show a, Eq a, Ord a, NFData a
+      , ToJSON a, FromJSON a
+      , Draw a, Brain a
+      ) => Entity a where
+  entityAttributes :: a -> EntityAttributes
+  entityAttributes = const defaultEntityAttributes
+  description :: a -> Text
+  entityChar :: a -> EntityChar
+  entityCollision :: a -> Maybe Collision
+  entityCollision = const $ Just Stop
+
+data SomeEntity where
+  SomeEntity :: forall a. (Entity a, Typeable a) => a -> SomeEntity
+
+instance Show SomeEntity where
+  show (SomeEntity e) = "SomeEntity (" <> show e <> ")"
+
+instance Eq SomeEntity where
+  (SomeEntity (a :: ea)) == (SomeEntity (b :: eb)) = case eqT @ea @eb of
+    Just Refl -> a == b
+    _ -> False
+
+instance Ord SomeEntity where
+  compare (SomeEntity (a :: ea)) (SomeEntity (b :: eb)) = case eqT @ea @eb of
+    Just Refl -> compare a b
+    _ -> compare (typeRep $ Proxy @ea) (typeRep $ Proxy @eb)
+
+
+instance NFData SomeEntity where
+  rnf (SomeEntity ent) = ent `deepseq` ()
+
+instance ToJSON SomeEntity where
+  toJSON (SomeEntity ent) = entityToJSON ent
+    where
+      entityToJSON :: forall entity. (Entity entity, Typeable entity)
+                   => entity -> JSON.Value
+      entityToJSON entity = JSON.object
+        [ "type" JSON..= tshow (typeRep @_ @entity Proxy)
+        , "data" JSON..= toJSON entity
+        ]
+
+instance Draw SomeEntity where
+  drawWithNeighbors ns (SomeEntity ent) = drawWithNeighbors ns ent
+  drawPriority (SomeEntity ent) = drawPriority ent
+
+instance Brain SomeEntity where
+  step ticks (Positioned p (SomeEntity ent)) =
+    fmap SomeEntity <$> step ticks (Positioned p ent)
+  entityCanMove (SomeEntity ent) = entityCanMove ent
+
+downcastEntity :: forall (a :: Type). (Typeable a) => SomeEntity -> Maybe a
+downcastEntity (SomeEntity e) = cast e
+
+entityIs :: forall (a :: Type). (Typeable a) => SomeEntity -> Bool
+entityIs = isJust . downcastEntity @a
+
+_SomeEntity :: forall a. (Entity a, Typeable a) => Prism' SomeEntity a
+_SomeEntity = prism' SomeEntity downcastEntity
+
+newtype DeriveEntity
+  (blocksVision :: Bool)
+  (description :: Symbol)
+  (entityChar :: Symbol)
+  (entity :: Type)
+  = DeriveEntity entity
+  deriving newtype (Show, Eq, Ord, NFData, ToJSON, FromJSON, Draw)
+
+instance Brain entity => Brain (DeriveEntity b d c entity) where
+  step = brainVia $ \(DeriveEntity e) -> e
+
+instance
+  ( KnownBool blocksVision
+  , KnownSymbol description
+  , KnownSymbol entityChar
+  , Show entity, Eq entity, Ord entity, NFData entity
+  , ToJSON entity, FromJSON entity
+  , Draw entity, Brain entity
+  )
+  => Entity (DeriveEntity blocksVision description entityChar entity) where
+  entityAttributes _ = defaultEntityAttributes
+    & blocksVision .~ boolVal @blocksVision
+  description _ = pack . symbolVal $ Proxy @description
+  entityChar _ = fromString . symbolVal $ Proxy @entityChar
+
+--------------------------------------------------------------------------------
+
+data GameLevel = GameLevel
+  { _levelEntities :: !(EntityMap SomeEntity)
+  , _upStaircasePosition :: !Position
+  , _levelRevealedPositions :: !(Set Position)
+  }
+  deriving stock (Show, Eq, Generic)
+  deriving anyclass (NFData)
+  deriving (ToJSON)
+       via WithOptions '[ FieldLabelModifier '[Drop 1] ]
+           GameLevel
+
+--------------------------------------------------------------------------------
+
+data Autocommand
+  = AutoMove Direction
+  deriving stock (Show, Eq, Ord, Generic)
+  deriving anyclass (NFData, Hashable, ToJSON, FromJSON, CoArbitrary, Function)
+  deriving Arbitrary via GenericArbitrary Autocommand
+{-# ANN module ("HLint: ignore Use newtype instead of data" :: String) #-}
+
+data AutocommandState
+  = NoAutocommand
+  | ActiveAutocommand Autocommand (Async ())
+  deriving stock (Eq, Ord, Generic)
+  deriving anyclass (Hashable)
+
+instance Show AutocommandState where
+  show NoAutocommand = "NoAutocommand"
+  show (ActiveAutocommand ac _) =
+    "(ActiveAutocommand " <> show ac <> " <Async>)"
+
+instance ToJSON AutocommandState where
+  toJSON = const Null
+
+instance FromJSON AutocommandState where
+  parseJSON Null = pure NoAutocommand
+  parseJSON _ = fail "Invalid AutocommandState; expected null"
+
+instance NFData AutocommandState where
+  rnf NoAutocommand = ()
+  rnf (ActiveAutocommand ac t) = ac `deepseq` t `seq` ()
+
+instance CoArbitrary AutocommandState where
+  coarbitrary NoAutocommand = variant @Int 1
+  coarbitrary (ActiveAutocommand ac t)
+    = variant @Int 2
+    . coarbitrary ac
+    . coarbitrary (hash t)
+
+instance Function AutocommandState where
+  function = functionMap onlyNoAC (const NoAutocommand)
+    where
+      onlyNoAC NoAutocommand = ()
+      onlyNoAC _ = error "Can't handle autocommands in Function"
+
+--------------------------------------------------------------------------------
+
+
+data DebugState = DebugState
+  { _allRevealed :: !Bool
+  }
+  deriving stock (Show, Eq, Generic)
+  deriving anyclass (NFData, CoArbitrary, Function)
+  deriving (ToJSON, FromJSON)
+       via WithOptions '[ FieldLabelModifier '[Drop 1] ]
+           DebugState
+{-# ANN DebugState ("HLint: ignore Use newtype instead of data" :: String) #-}
+
+instance Arbitrary DebugState where
+  arbitrary = genericArbitrary
+
+data GameState = GameState
+  { _levels            :: !(Levels GameLevel)
+  , _characterEntityID :: !EntityID
+  , _messageHistory    :: !MessageHistory
+  , _randomGen         :: !StdGen
+
+    -- | The active panel displayed in the UI, if any
+  , _activePanel       :: !(Maybe Panel)
+
+  , _promptState       :: !(GamePromptState AppM)
+  , _debugState        :: !DebugState
+  , _autocommand       :: !AutocommandState
+  }
+  deriving stock (Show, Generic)
+  deriving anyclass (NFData)
+  deriving (ToJSON)
+       via WithOptions '[ FieldLabelModifier '[Drop 1] ]
+           GameState
+
+makeLenses ''GameLevel
+makeLenses ''GameState
+
+entities :: Lens' GameState (EntityMap SomeEntity)
+entities = levels . current . levelEntities
+
+revealedPositions :: Lens' GameState (Set Position)
+revealedPositions = levels . current . levelRevealedPositions
+
+instance Eq GameState where
+  (==) = (==) `on` \gs ->
+    ( gs ^. entities
+    , gs ^. revealedPositions
+    , gs ^. characterEntityID
+    , gs ^. messageHistory
+    , gs ^. activePanel
+    , gs ^. debugState
+    )
+
+--------------------------------------------------------------------------------
+
+runAppT :: Monad m => AppT m a -> GameEnv -> GameState -> m (a, GameState)
+runAppT appt env initialState
+  = flip runStateT initialState
+  . flip runReaderT env
+  . unAppT
+  $ appt
+
+instance (Monad m) => MonadRandom (AppT m) where
+  getRandomR rng = randomGen %%= randomR rng
+  getRandom = randomGen %%= random
+  getRandomRs rng = uses randomGen $ randomRs rng
+  getRandoms = uses randomGen randoms
+
+instance MonadTransControl AppT where
+  type StT AppT a = (a, GameState)
+  liftWith f
+    = AppT
+    . ReaderT $ \e
+    -> StateT $ \s
+    -> (,s) <$> f (\action -> runAppT action e s)
+  restoreT = AppT . ReaderT . const . StateT . const
+
+--------------------------------------------------------------------------------
+
+makeLenses ''DebugState
+makePrisms ''AutocommandState