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{-# LANGUAGE RecordWildCards #-}
--------------------------------------------------------------------------------
module Xanthous.Game.Lenses
( positionedCharacter
, character
, characterPosition
, updateCharacterVision
, getInitialState
-- * Collisions
, Collision(..)
, collisionAt
) where
--------------------------------------------------------------------------------
import Xanthous.Prelude
--------------------------------------------------------------------------------
import System.Random
import Control.Monad.State
--------------------------------------------------------------------------------
import Xanthous.Game.State
import Xanthous.Data
import qualified Xanthous.Data.EntityMap as EntityMap
import Xanthous.Data.EntityMap.Graphics (visiblePositions)
import Xanthous.Entities.Character (Character, mkCharacter)
import Xanthous.Entities.Environment (Door, open)
import Xanthous.Entities.Item (Item)
import Xanthous.Entities.Creature (Creature)
--------------------------------------------------------------------------------
getInitialState :: IO GameState
getInitialState = do
_randomGen <- getStdGen
let char = mkCharacter
(_characterEntityID, _entities)
= EntityMap.insertAtReturningID
(Position 0 0)
(SomeEntity char)
mempty
_messageHistory = mempty
_revealedPositions = mempty
_promptState = NoPrompt
_debugState = DebugState
{ _allRevealed = False
}
pure GameState {..}
positionedCharacter :: Lens' GameState (Positioned Character)
positionedCharacter = lens getPositionedCharacter setPositionedCharacter
where
setPositionedCharacter :: GameState -> Positioned Character -> GameState
setPositionedCharacter game char
= game
& entities . at (game ^. characterEntityID)
?~ fmap SomeEntity char
getPositionedCharacter :: GameState -> Positioned Character
getPositionedCharacter game
= over positioned
( fromMaybe (error "Invariant error: Character was not a character!")
. downcastEntity
)
. fromMaybe (error "Invariant error: Character not found!")
$ EntityMap.lookupWithPosition
(game ^. characterEntityID)
(game ^. entities)
character :: Lens' GameState Character
character = positionedCharacter . positioned
characterPosition :: Lens' GameState Position
characterPosition = positionedCharacter . position
visionRadius :: Word
visionRadius = 12 -- TODO make this dynamic
-- | Update the revealed entities at the character's position based on their vision
updateCharacterVision :: GameState -> GameState
updateCharacterVision game =
let charPos = game ^. characterPosition
visible = visiblePositions charPos visionRadius $ game ^. entities
in game & revealedPositions <>~ visible
data Collision
= Stop
| Combat
deriving stock (Show, Eq, Ord, Generic)
deriving anyclass (NFData)
collisionAt :: MonadState GameState m => Position -> m (Maybe Collision)
collisionAt pos = do
ents <- use $ entities . EntityMap.atPosition pos
pure $
if | null ents -> Nothing
| any (entityIs @Creature) ents -> pure Combat
| all (entityIs @Item) ents -> Nothing
| doors@(_ : _) <- ents ^.. folded . _SomeEntity @Door
, all (view open) doors -> Nothing
| otherwise -> pure Stop
|