Add xmonad keybinding to force fullscreen

Signed-off-by: Magic_RB <magic_rb@redalder.org>

home-manager/modules/xmonad/xmonad.hs

@@ -11,8 +11,12 @@
 -- Normally, you'd only override those defaults you care about.
 --
 
+{-# LANGUAGE BlockArguments
+#-}
+
 import XMonad
 import Data.Monoid
+import Data.List (delete)
 import Data.Maybe
 import Data.Function
 import Data.Functor
@@ -159,6 +163,23 @@ myKeymap c =
      , ("<XF86TouchpadToggle>"    , spawn "@toggle_touchpad@")
 
      , ("M-<F1>", spawn "@auxmenu@")
+
+     , ("M-<F11>", withDisplay $ \dpy -> withFocused $ \win -> do
+            wmstate <- getAtom "_NET_WM_STATE"
+            fullsc <- getAtom "_NET_WM_STATE_FULLSCREEN"
+            wstate <- fromMaybe [] `fmap` getProp32 wmstate win
+
+            let
+              ptype = 4
+              chWstate f = io $ changeProperty32 dpy win wmstate ptype propModeReplace (f wstate)
+              isFull = fromIntegral fullsc `elem` wstate
+
+            when (not isFull) $ do
+              chWstate (fromIntegral fullsc:)
+              windows $ W.float win $ W.RationalRect 0 0 1 1
+            when isFull $ do
+              chWstate $ delete (fromIntegral fullsc)
+              windows $ W.sink win)
     ]
     ++