{-# OPTIONS_GHC -fallow-undecidable-instances #-}
{-# LANGUAGE FlexibleInstances #-}
-----------------------------------------------------------------------------
-- |
-- Module : XMonadContrib.Combo
-- Copyright : (c) David Roundy <droundy@darcs.net>
-- License : BSD-style (see LICENSE)
--
-- Maintainer : David Roundy <droundy@darcs.net>
-- Stability : unstable
-- Portability : unportable
--
-- A layout that combines multiple layouts.
--
-----------------------------------------------------------------------------
module XMonadContrib.Combo (
-- * Usage
-- $usage
combo
) where
import Control.Arrow ( first )
import Data.List ( delete )
import Data.Maybe ( isJust )
import XMonad
import StackSet ( integrate, Stack(..) )
import qualified StackSet as W ( differentiate )
-- $usage
--
-- To use this layout write, in your Config.hs:
--
-- > import XMonadContrib.Combo
--
-- and add something like
--
-- > combo (twoPane 0.03 0.5) [(full,1),(tabbed shrinkText defaultTConf,1)]
--
-- to your defaultLayouts.
--
-- The first argument to combo is a layout that will divide the screen into
-- one or more subscreens. The second argument is a list of layouts which
-- will be used to lay out the contents of each of those subscreens.
-- Paired with each of these layouts is an integer giving the number of
-- windows this section should hold. This number is ignored for the last
-- layout, which will hold any excess windows.
-- %import XMonadContrib.Combo
-- %layout , combo (twoPane 0.03 0.5) [(full,1),(tabbed shrinkText defaultTConf,1)]
combo :: (Eq a, Show a, Read a, ReadableLayout a, LayoutClass l (Layout a, Int))
=> (l (Layout a, Int)) -> [(Layout a, Int)] -> Combo l a
combo = Combo []
data Combo l a = Combo [a] (l (Layout a, Int)) [(Layout a, Int)]
deriving ( Show, Read )
instance (Eq a, Show a, Read a, ReadableLayout a, LayoutClass l (Layout a, Int))
=> LayoutClass (Combo l) a where
doLayout (Combo f super origls) rinput s = arrange (integrate s)
where arrange [] = return ([], Just $ Combo [] super origls)
arrange [w] = return ([(w,rinput)], Just $ Combo [w] super origls)
arrange origws =
do (lrs, msuper') <- runLayout super rinput (W.differentiate $ take (length origws) origls)
let super' = maybe super id msuper'
f' = focus s:delete (focus s) f
lwrs [] _ = []
lwrs [((l,_),r)] ws = [((l,r),differentiate f' ws)]
lwrs (((l,n),r):xs) ws = ((l,r),differentiate f' $ take len1 ws) : lwrs xs (drop len1 ws)
where len1 = min n (length ws - length xs)
out <- mapM (uncurry $ uncurry runLayout) $ lwrs lrs origws
let origls' = zipWith foo (out++repeat ([],Nothing)) origls
foo (_, Nothing) x = x
foo (_, Just l') (_, n) = (l', n)
return (concat $ map fst out, Just $ Combo f' super' origls')
differentiate :: Eq q => [q] -> [q] -> Maybe (Stack q)
differentiate (z:zs) xs | z `elem` xs = Just $ Stack { focus=z
, up = reverse $ takeWhile (/=z) xs
, down = tail $ dropWhile (/=z) xs }
| otherwise = differentiate zs xs
differentiate [] xs = W.differentiate xs
handleMessage (Combo f super origls) m =
do mls <- broadcastPrivate m (map fst origls)
let mls' = (\x->zipWith first (map const x) origls) `fmap` mls
msuper <- broadcastPrivate m [super]
case msuper of
Just [super'] -> return $ Just $ Combo f super' $ maybe origls id mls'
_ -> return $ Combo f super `fmap` mls'
broadcastPrivate :: LayoutClass l b => SomeMessage -> [l b] -> X (Maybe [l b])
broadcastPrivate a ol = do nml <- mapM f ol
if any isJust nml
then return $ Just $ zipWith ((flip maybe) id) ol nml
else return Nothing
where f l = handleMessage l a `catchX` return Nothing
