-----------------------------------------------------------------------------
-- |
-- 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.Maybe ( isJust )
import XMonad
import StackSet ( integrate, differentiate )
-- $usage
--
-- To use this layout write, in your Config.hs:
--
-- > import XMonadContrib.Combo
-- > import XMonadContrib.SimpleStacking
--
-- and add something like
--
-- > simpleStacking $ combo (twoPane 0.03 0.5) [(full,1),(tabbed shrinkText,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 subscreents.
-- 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.
combo :: Layout (Layout a, Int) -> [(Layout a, Int)] -> Layout a
combo super origls = Layout { doLayout = \r s -> arrange r (integrate s), modifyLayout = message }
where arrange _ [] = return ([], Nothing)
arrange r [w] = return ([(w,r)], Nothing)
arrange rinput origws =
do lrs <- fst `fmap`
runLayout super rinput (differentiate $ take (length origws) origls)
let lwrs [] _ = []
lwrs [((l,_),r)] ws = [((l,r),differentiate ws)]
lwrs (((l,n),r):xs) ws = ((l,r),differentiate $ 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 super origls')
message 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 super' $ maybe origls id mls'
_ -> return $ combo super `fmap` mls'
broadcastPrivate :: SomeMessage -> [Layout b] -> X (Maybe [Layout 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 = modifyLayout l a `catchX` return Nothing
