{-# OPTIONS_GHC -fglasgow-exts #-}
-----------------------------------------------------------------------------
-- |
-- Module      :  XMonad.Actions.CopyWindow
-- Copyright   :  (c) David Roundy <droundy@darcs.net>
-- License     :  BSD3-style (see LICENSE)
--
-- Maintainer  :  David Roundy <droundy@darcs.net>
-- Stability   :  unstable
-- Portability :  unportable
--
-- Provides a binding to duplicate a window on multiple workspaces,
-- providing dwm-like tagging functionality.
--
-----------------------------------------------------------------------------

module XMonad.Actions.CopyWindow (
                                 -- * Usage
                                 -- $usage
                                 copy, copyWindow, kill1
                                ) where

import Prelude hiding ( filter )
import qualified Data.List as L
import XMonad hiding (modify)
import XMonad.StackSet

-- $usage
--
-- You can use this module with the following in your @~\/.xmonad\/xmonad.hs@ file:
--
-- > import XMonad.Actions.CopyWindow
--
-- Then add something like this to your keybindings:
--
-- > -- mod-[1..9] @@ Switch to workspace N
-- > -- mod-shift-[1..9] @@ Move client to workspace N
-- > -- mod-control-shift-[1..9] @@ Copy client to workspace N
-- > [((m .|. modMask x, k), windows $ f i)
-- >     | (i, k) <- zip (workspaces x) [xK_1 ..]
-- >     , (f, m) <- [(W.view, 0), (W.shift, shiftMask), (copy, shiftMask .|. controlMask)]]
--
-- To use the above key bindings you need also to import
-- "XMonad.StackSet":
--
-- > import qualified XMonad.StackSet as W
--
-- You may also wish to redefine the binding to kill a window so it only
-- removes it from the current workspace, if it's present elsewhere:
--
-- >  , ((modMask x .|. shiftMask, xK_c     ), kill1) -- @@ Close the focused window
--
-- For detailed instructions on editing your key bindings, see
-- "XMonad.Doc.Extending#Editing_key_bindings".

-- | copy. Copy the focussed window to a new workspace.
copy :: WorkspaceId -> WindowSet -> WindowSet
copy n s | Just w <- peek s = copyWindow w n s
         | otherwise = s

-- | copyWindow.  Copy a window to a new workspace
copyWindow :: Window -> WorkspaceId -> WindowSet -> WindowSet
copyWindow w n = copy'
    where copy' s = if n `tagMember` s
                    then view (tag (workspace (current s))) $ insertUp' w $ view n s
                    else s
          insertUp' a s = modify (Just $ Stack a [] [])
                          (\(Stack t l r) -> if a `elem` t:l++r
                                             then Just $ Stack t l r
                                             else Just $ Stack a (L.delete a l) (L.delete a (t:r))) s


-- | Remove the focused window from this workspace.  If it's present in no
-- other workspace, then kill it instead. If we do kill it, we'll get a
-- delete notify back from X.
--
-- There are two ways to delete a window. Either just kill it, or if it
-- supports the delete protocol, send a delete event (e.g. firefox)
--
kill1 :: X ()
kill1 = do ss <- gets windowset
           whenJust (peek ss) $ \w -> if member w $ delete'' w ss
                                      then windows $ delete'' w
                                      else kill
    where delete'' w = modify Nothing (filter (/= w))