Add ability to flip the layout with mod-f.

1 files changed, 36 insertions, 7 deletions

diff --git a/src/Internal/Layout.hs b/src/Internal/Layout.hs
index 2339cca..aa3df1a 100644
--- a/src/Internal/Layout.hs
+++ b/src/Internal/Layout.hs
@@ -1,6 +1,7 @@
 {-# LANGUAGE MultiParamTypeClasses, FlexibleInstances #-}
 module Internal.Layout where 
 
+import Control.Arrow (second)
 import XMonad.Hooks.ManageDocks
 import XMonad.Layout.Circle
 import XMonad.Layout.Accordion
@@ -20,26 +21,54 @@ import qualified XMonad.StackSet as W
 
 myLayout =
   ModifiedLayout (Zoomable False 0.05 0.05) $
-    spacingRaw True (Border 5 5 5 5) True (Border 5 5 5 5) True $ avoidStruts $
-      spiral (6/7) |||
-      Tall 1 (3/100) (1/2) |||
-      ThreeCol 1 (3/100) (1/2) |||
-      Full |||
-      Grid |||
-      Dishes 2 (1/6)
+    ModifiedLayout (Flippable False) $
+      spacingRaw True (Border 5 5 5 5) True (Border 5 5 5 5) True $ avoidStruts $
+        spiral (6/7) |||
+        Tall 1 (3/100) (1/2) |||
+        ThreeCol 1 (3/100) (1/2) |||
+        Full |||
+        Grid |||
+        Dishes 2 (1/6)
 
 data ResizeZoom = ShrinkZoom | ExpandZoom deriving (Typeable)
 
 instance Message ResizeZoom where
 
+data Flippable a = Flippable Bool -- True if flipped
+  deriving (Show, Read)
+
+data FlipLayout = FlipLayout deriving (Typeable)
+
 data Zoomable a = Zoomable Bool Float Float -- True if zooming in on the focused window.
   deriving (Show, Read)
 
 data ToggleZoom = ToggleZoom
   deriving (Typeable)
 
+instance Message FlipLayout where
+
 instance Message ToggleZoom where
 
+instance (Eq a) => LayoutModifier Flippable a where
+  pureModifier (Flippable flip) (Rectangle _ _ sw _) stack returned =
+    if flip 
+      then (map (second doFlip) returned, Nothing)
+      else (returned, Nothing)
+    where
+      doFlip (Rectangle x y w h) = Rectangle (fromIntegral sw - x - fromIntegral w) y w h
+
+  pureMess (Flippable flip) message = 
+    case fromMessage message of
+      Just FlipLayout -> Just (Flippable (not flip))
+      Nothing -> Nothing
+
+  modifyDescription (Flippable flipped) underlying =
+    let descr = description underlying in
+      if flipped
+        then descr ++ " Flipped"
+        else descr
+    
+
 instance (Eq a) => LayoutModifier Zoomable a where
   redoLayout (Zoomable doit ws hs) (Rectangle x y w h) stack returned =
     if doit