finished storing ui widgets into a HashMap and referencing them by UIId.

Additionally, widgets functions now use the Pioneers monad.
Branch is compiling again and works.

src/UI/UIOperations.hs

@@ -1,26 +1,79 @@
 module UI.UIOperations where
 
+import           Control.Monad       (liftM)
 import qualified Data.HashMap.Strict as Map
+import           Data.Maybe
 
+import Types
 import UI.UIBaseData
 import UI.UIClasses
 
 defaultUIState :: UIButtonState
 defaultUIState = UIButtonState False False False False False False
 
---TODO
--- |The function 'isInside' tests whether a point is inside the widget or any child.
---  A screen position may be inside the bounding box of a widget but not considered part of the component.
---  The function returns all hit widgets that have no hit children or 'Nothing' if the point neither hits any
---  component nor the parent widget itself.
-isInside :: ScreenUnit -- ^screen x coordinate
-         -> ScreenUnit -- ^screen y coordinate
-         -> UIId       -- ^the parent widget
-         -> [UIId]
-isInside x' y' wg =
-    case isInsideSelf x' y' wg of -- test inside parent's bounding box
-        False -> []
-        True -> case concat $ map (isInside x' y') (getChildren wg) of
-            [] -> [toGUIAny wg]
-            l  -> l
+toGUIAny :: Map.HashMap UIId (GUIAny m) -> UIId -> GUIAny m
+toGUIAny m uid = case Map.lookup uid m of
+                     Just w  -> w
+                     Nothing -> error "map does not contain requested key" --TODO: better error handling
+{-# INLINE toGUIAny #-}
+
+toGUIAnys :: Map.HashMap UIId (GUIAny m) -> [UIId] -> [GUIAny m]
+toGUIAnys m ids = mapMaybe (flip Map.lookup m) ids
+{-# INLINE toGUIAnys #-}
+-- TODO: check for missing components?
+
+
+-- |The function 'getInside' returns child widgets that overlap with a specific
+--  screen position.
+--  
+--  A screen position may be inside the bounding box of a widget but not
+--  considered part of the component. The function returns all hit widgets that 
+--  have no hit children, which may be the input widget itself,
+--  or @[]@ if the point does not hit the widget.
+--  
+--  This function returns the widgets themselves unlike 'getInsideId'.
+getInside :: Map.HashMap UIId (GUIAny Pioneers) -- ^map containing ui widgets
+             -> ScreenUnit -- ^screen x coordinate
+             -> ScreenUnit -- ^screen y coordinate
+             -> GUIAny Pioneers  -- ^the parent widget
+             -> Pioneers [GUIAny Pioneers]
+getInside hMap x' y' wg = do
+  inside <- isInside x' y' wg
+  if inside -- test inside parent's bounding box
+  then do
+       childrenIds <- getChildren wg
+       hitChildren <- liftM concat $ mapM (getInside hMap x' y') (toGUIAnys hMap childrenIds)
+       case hitChildren of
+            [] -> return [wg]
+            _ -> return hitChildren
+  else return []
 --TODO: Priority queue?
+
+-- |The function 'getInsideId' returns child widgets that overlap with a 
+--  specific screen position.
+--  
+--  A screen position may be inside the bounding box of a widget but not
+--  considered part of the component. The function returns all hit widgets that 
+--  have no hit children, which may be the input widget itself,
+--  or @[]@ if the point does not hit the widget.
+--  
+--  This function returns the 'UIId's of the widgets unlike 'getInside'.
+getInsideId :: Map.HashMap UIId (GUIAny Pioneers) -- ^map containing ui widgets
+            -> ScreenUnit -- ^screen x coordinate
+            -> ScreenUnit -- ^screen y coordinate
+            -> UIId  -- ^the parent widget
+            -> Pioneers [UIId]
+getInsideId hMap x' y' uid = do
+  let wg = toGUIAny hMap uid
+  inside <- isInside x' y' wg
+  if inside -- test inside parent's bounding box
+    then do
+      childrenIds <- getChildren wg
+      hitChildren <- liftM concat $ mapM (getInsideId hMap x' y') childrenIds
+      case hitChildren of
+           [] -> return [uid]
+           _  -> return hitChildren
+    else return []
+--TODO: Priority queue?
+
+