1 files changed, 96 insertions, 0 deletions
diff --git a/src/Xmobar/Plugins/Kbd.hs b/src/Xmobar/Plugins/Kbd.hs
new file mode 100644
index 0000000..f4dad36
--- /dev/null
+++ b/src/Xmobar/Plugins/Kbd.hs
@@ -0,0 +1,96 @@
+-----------------------------------------------------------------------------
+-- |
+-- Module      :  Plugins.Kbd
+-- Copyright   :  (c) Martin Perner
+-- License     :  BSD-style (see LICENSE)
+--
+-- Maintainer  :  Martin Perner <martin@perner.cc>
+-- Stability   :  unstable
+-- Portability :  unportable
+--
+-- A keyboard layout indicator for Xmobar
+--
+-----------------------------------------------------------------------------
+
+module Xmobar.Plugins.Kbd(Kbd(..)) where
+
+import Data.List (isPrefixOf, findIndex)
+import Data.Maybe (fromJust)
+import Control.Monad (forever)
+import Graphics.X11.Xlib
+import Graphics.X11.Xlib.Extras
+
+import Xmobar.Run.Commands
+import Xmobar.Utils (nextEvent')
+import Xmobar.System.Kbd
+
+
+-- 'Bad' prefixes of layouts
+noLaySymbols :: [String]
+noLaySymbols = ["group", "inet", "ctr", "pc", "ctrl"]
+
+
+-- splits the layout string into the actual layouts
+splitLayout :: String -> [String]
+splitLayout s = splitLayout' noLaySymbols $ split s '+'
+
+splitLayout' :: [String] ->  [String] -> [String]
+--                  end of recursion, remove empty strings
+splitLayout' [] s = map (takeWhile (/= ':')) $ filter (not . null) s
+--                    remove current string if it has a 'bad' prefix
+splitLayout' bad s  =
+  splitLayout' (tail bad) [x | x <- s, not $ isPrefixOf (head bad) x]
+
+-- split String at each Char
+split :: String -> Char -> [String]
+split [] _ = [""]
+split (c:cs) delim
+    | c == delim = "" : rest
+    | otherwise = (c : head rest) : tail rest
+        where
+            rest = split cs delim
+
+-- replaces input string if on search list (exact match) with corresponding
+-- element on replacement list.
+--
+-- if not found, return string unchanged
+searchReplaceLayout :: KbdOpts -> String -> String
+searchReplaceLayout opts s = let c = findIndex (\x -> fst x == s) opts in
+    case c of
+        Nothing -> s
+        x -> let i = fromJust x in snd $ opts!!i
+
+-- returns the active layout
+getKbdLay :: Display -> KbdOpts -> IO String
+getKbdLay dpy opts = do
+        lay <- getLayoutStr dpy
+        curLay <- getKbdLayout dpy
+        return $ searchReplaceLayout opts $ splitLayout lay!!curLay
+
+
+
+newtype Kbd = Kbd [(String, String)]
+  deriving (Read, Show)
+
+instance Exec Kbd where
+        alias (Kbd _) = "kbd"
+        start (Kbd opts) cb = do
+
+            dpy <- openDisplay ""
+
+            -- initial set of layout
+            cb =<< getKbdLay dpy opts
+
+            -- enable listing for
+            -- group changes
+            _ <- xkbSelectEventDetails dpy xkbUseCoreKbd xkbStateNotify xkbAllStateComponentsMask xkbGroupStateMask
+            -- layout/geometry changes
+            _ <- xkbSelectEvents dpy  xkbUseCoreKbd xkbNewKeyboardNotifyMask xkbNewKeyboardNotifyMask
+
+            allocaXEvent $ \e -> forever $ do
+                nextEvent' dpy e
+                _ <- getEvent e
+                cb =<< getKbdLay dpy opts
+
+            closeDisplay dpy
+            return ()