[refactor] Change dragging behavior to use the motion event.

1 files changed, 12 insertions, 12 deletions

diff --git a/plug/src/Config.hs b/plug/src/Config.hs
index e80f360..5cf616f 100644
--- a/plug/src/Config.hs
+++ b/plug/src/Config.hs
@@ -50,6 +50,14 @@ instance StateExtension Dragging where
   marshalExtension _ = Nothing
   demarshalExtension _ = Nothing
 
+newtype CursorPosition = CursorPosition (Double, Double)
+  deriving (Typeable)
+
+instance StateExtension CursorPosition where
+  initialValue = CursorPosition (0, 0)
+  marshalExtension _ = Nothing
+  demarshalExtension _ = Nothing
+
 leftButton :: Word32
 leftButton = 272 -- BTN_LEFT
 
@@ -58,8 +66,8 @@ onButton ev
   | buttonEvent_button ev /= leftButton = return ()
   | buttonEvent_state ev == ButtonPressed = do
       self <- getSelfPtr
+      CursorPosition (x, y) <- fromMaybe (CursorPosition (0, 0)) <$> xStateGet
       newDrag <- liftIO $ do
-        (x, y) <- getCursorPosition self
         tl <- foreign_toplevelAt (unwrapSelf self) (realToFrac x) (realToFrac y)
         if tl == nullPtr
           then return (Dragging Nothing)
@@ -74,13 +82,13 @@ onButton ev
   | otherwise = return ()
 
 onMotion :: MotionEvent -> Montis ()
-onMotion _ev = do
+onMotion ev = do
+  let (x, y) = motionEvent_absolute ev
+  xStatePut (CursorPosition (x, y))
   Dragging mdrag <- fromMaybe (Dragging Nothing) <$> xStateGet
   case mdrag of
     Nothing -> return ()
     Just (DragState tl dx dy) -> do
-      self <- getSelfPtr
-      (x, y) <- liftIO $ getCursorPosition self
       liftIO $
         foreign_setToplevelPosition
           tl
@@ -90,14 +98,6 @@ onMotion _ev = do
 unwrapSelf :: SelfPtr -> Ptr Void
 unwrapSelf (SelfPtr p) = p
 
-getCursorPosition :: SelfPtr -> IO (Double, Double)
-getCursorPosition self =
-  alloca $ \xPtr -> alloca $ \yPtr -> do
-    foreign_getCursorPosition (unwrapSelf self) xPtr yPtr
-    x <- peek xPtr
-    y <- peek yPtr
-    return (realToFrac (x :: CDouble), realToFrac (y :: CDouble))
-
 getToplevelPosition :: Ptr ForeignMontisToplevel -> IO (Double, Double)
 getToplevelPosition tl =
   alloca $ \xPtr -> alloca $ \yPtr -> do