-- Let's be honest. The appeal of XMonad is that it lets you
-- indulge two guilty pleasures at once: OCD and using crazy
-- programming languages.
--
-- This setup assumes you have a GNOME+xmonad setup using something like:
--   /usr/share/xsessions/xmonad-gnome.desktop
--   /usr/share/gnome-session/sessions/xmonad.session
--
-- Add this to gnome-session-properties for extra focus cues:
--   xcompmgr -nfCF -D5

import Control.Monad
import qualified Data.Map as M
import XMonad hiding ((|||))
import XMonad.Layout.LayoutCombinators ((|||))
import qualified XMonad.StackSet as W
import XMonad.Util.Replace
import XMonad.Util.EZConfig
import XMonad.Util.Stack
import XMonad.Config.Gnome
import XMonad.Hooks.ManageDocks
import XMonad.Hooks.ManageHelpers
import XMonad.Hooks.DynamicLog
import XMonad.Hooks.InsertPosition
import XMonad.Hooks.FadeWindows
import XMonad.Layout.Named
import XMonad.Layout.Grid
import XMonad.Layout.NoBorders
import XMonad.Layout.MouseResizableTile
import XMonad.Layout.BoringWindows
import XMonad.Layout.LayoutHints
import XMonad.Layout.ToggleLayouts
import XMonad.Actions.UpdatePointer
import XMonad.Actions.CycleSelectedLayouts

--TODO:
-- Suppress updatePointer if button1 is down (chromium tab drag)
-- Preserve sizes by window instead of position (i.e., let my terminals be small)
-- Always add new windows to left side and increment number in left side?
-- Shrink all slaves in same pane when adding rather than only splitting next
-- Focus previous when closing, not next (inverse of insertPosition)
-- FadeWindows - Why did my setup stop working?
-- Suppress border flash on workspace switch

main = do
	replace
	xmonad $ gnomeConfig { -- start with GNOME compatible base
		modMask    = mod4Mask, -- Windows key not used by apps
		terminal   = "x-terminal-emulator", -- use debian/ubuntu system setting
		workspaces = (workspaces gnomeConfig) ++ [show 0], -- add 0 for an even ten
		keys       = \cfg -> M.union (keys gnomeConfig cfg)
		                             (M.fromList $ [
		                               ((modMask cfg, xK_u), sendMessage ShrinkSlave),
		                               ((modMask cfg, xK_i), sendMessage ExpandSlave)
		                              ] ++ workspaceHotkeys cfg xK_0 0),
		manageHook =  manageHook gnomeConfig
		               -- support fullscreen
		               <+> (isFullscreen --> doFullFloat)
		               -- insert new windows after current instead of before
		               <+> insertPosition Below Newer
		               -- allow space for gnome panel
		               <+> manageDocks,
		logHook    = logHook gnomeConfig
		               -- switch to grid and back depending on number of windows
		               <+> pickLayout [((<=), 8, ["mrt"]),
		                               ((>=), 9, ["Grid"])]
		               -- make non focused windows slightly translucent
		               <+> (fadeWindowsLogHook $
		                     opaque
									-- <+> (isFloating --> transparency 0.1)
									<+> (isUnfocused --> transparency 0.15)
									)
		               -- warp mouse when changing focus with keyboard
		               <+> smartUpdatePointer (Relative 0.5 0.5)
							-- <+> dynamicLog
							,
		-- make non focused windows slightly translucent
		handleEventHook = handleEventHook gnomeConfig <+> fadeWindowsEventHook,
		-- no window decorations
		layoutHook =
			smartBorders  $ -- no red border around fullscreen youtube videos
			avoidStruts   $ -- leave space for gnome panel (?)
			boringWindows $ -- is this for dialog windows?
			layoutHintsWithPlacement (0.5, 0.5) $ -- padding around gvim and pterm to fit font
			(named "mrt"  $ -- make it possible to jump to this
				noBorders  $ -- clicking screen edge hits scrollbar instead of border
				mouseResizableTile { -- two column tiled layout
					draggerType = FixedDragger {
						gapWidth     = 4, -- big enough to see and click,
						draggerWidth = 4  -- small enough to stay out of the way
			}}) ||| Grid -- for >=9 windows (names itself)
	} where
		workspaceHotkeys cfg key num = [
			((              modMask cfg, key), windows $ W.greedyView $ show num),
			((shiftMask .|. modMask cfg, key), windows $ W.shift      $ show num)]
		windowCount = foldlZ_ (\count win -> 1+count) 0 . W.stack . W.workspace . W.current
		isDragging :: Query Bool
		isDragging = liftX $ gets dragging >>= \dr -> case dr of
			Just (d,_) -> return True
			Nothing    -> return False
		smartUpdatePointer :: PointerPosition -> X () -- this doesn't work
		smartUpdatePointer p = gets dragging >>= \dr -> case dr of
			Just (d,_) -> return ()
			Nothing    -> updatePointer p
		pickLayout :: [((Integer -> Integer -> Bool), Integer, [String])] -> X ()
		pickLayout checks = do
			ws <- gets windowset
			let howMany = windowCount ws in do
				forM_ checks $ \(op, val, names) -> do
					when (howMany `op` val) (cycleThroughLayouts names)