#4 Setup interaction

lib/RPGEngine/Data/Level.hs

@@ -5,8 +5,9 @@ where
 import GHC.IO (unsafePerformIO)
 import System.Directory (getDirectoryContents)
 import RPGEngine.Input.Core (ListSelector(..))
-import RPGEngine.Data (Level (..), Physical (..), Direction (..), Entity (..), Game (..), Item (..), Player (..), State (..), X, Y, Layout)
+import RPGEngine.Data (Action(..), Level (..), Physical (..), Direction (..), Entity (..), Game (..), Item (..), Player (..), State (..), X, Y, Layout, Condition (InventoryFull, InventoryContains, Not, AlwaysFalse))
 import RPGEngine.Config (levelFolder)
+import Data.Foldable (find)
 
 ------------------------------ Exported ------------------------------
 
@@ -25,6 +26,17 @@ findAt pos lvl@Level{ index = index } = try
           try     | not (null matches) = head matches
                   | otherwise          = Void
 
+hasAt :: (X, Y) -> Level -> Maybe (Either Item Entity)
+hasAt pos level = match firstItem firstEntity
+    where match :: Maybe Item -> Maybe Entity -> Maybe (Either Item Entity)
+          match (Just a) _ = Just $ Left a
+          match _ (Just a) = Just $ Right a
+          match _ _        = Nothing
+          firstEntity = find ((== pos) . getECoord) $ entities level
+          getECoord e = (entityX e, entityY e)
+          firstItem   = find ((== pos) . getICoord) $ items level
+          getICoord i = (itemX i, itemY i)
+
 directionOffsets :: Direction -> (X, Y)
 directionOffsets North  = ( 0,  1)
 directionOffsets East   = ( 1,  0)
@@ -33,4 +45,29 @@ directionOffsets West   = (-1,  0)
 directionOffsets Stay   = ( 0,  0)
 
 getLevelList :: [FilePath]
-getLevelList = drop 2 $ unsafePerformIO $ getDirectoryContents levelFolder
+getLevelList = drop 2 $ unsafePerformIO $ getDirectoryContents levelFolder
+
+-- Get the actions of either an entity or an item
+getActions :: Either Item Entity -> [([Condition], Action)]
+getActions (Left item)    = itemActions item
+getActions (Right entity) = entityActions entity
+
+getActionText :: Action -> String
+getActionText Leave            = "Leave"
+getActionText (RetrieveItem _) = "Pick up"
+getActionText (UseItem _)      = "Use item"
+getActionText _ = "ERROR"
+
+-- TODO Check conditions
+-- Filter based on the conditions, keep only the actions of which the
+-- conditions are met.
+filterActions :: [([Condition], Action)] -> [Action]
+filterActions [] = []
+filterActions ((conditions, action):others) = action:filterActions others
+
+-- Check if a condition is met or not.
+meetsCondition :: Condition -> Bool
+meetsCondition InventoryFull          = False -- TODO
+meetsCondition (InventoryContains id) = True -- TODO
+meetsCondition (Not condition)        = not $ meetsCondition condition
+meetsCondition AlwaysFalse            = False