summaryrefslogtreecommitdiffhomepage
path: root/XMobar.hs
blob: 2b8aa4cd34377cff6cf1af14c2f3c07747f36fc2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
{-# OPTIONS -fglasgow-exts #-}
-----------------------------------------------------------------------------
-- |
-- Module      :  XMobar
-- Copyright   :  (c) Andrea Rossato
-- License     :  BSD-style (see LICENSE)
-- 
-- Maintainer  :  Andrea Rossato <andrea.rossato@unibz.it>
-- Stability   :  unstable
-- Portability :  unportable
--
-- A status bar for the Xmonad Window Manager 
--
-----------------------------------------------------------------------------

module XMobar (-- * Main Stuff
               -- $main
               Xbar
              , runXMobar
              , eventLoop
              , createWin
              -- * Printing
              -- $print
              , drawInWin
              , printStrings
              -- * Program Execution
              -- $commands
              , getOptions
              , execCommands
              , execCommand
              , runCommandLoop
              , readVariables
              -- * Unmamaged Windows
              -- $unmanwin
              , mkUnmanagedWindow
              -- * Useful Utilities
              , initColor
              , io
              ) where

import Graphics.X11.Xlib
import Graphics.X11.Xlib.Misc

import Control.Monad.State
import Control.Monad.Reader
import Control.Concurrent

import System.Process
import System.Exit
import System.IO (hClose, hGetLine)

import Config
import Parsers

-- $main
--
-- The XMobar data type and basic loops and functions.

-- | This is just esthetics, stolen from XMonad: see 'runXMobar'
newtype Xbar a = X (ReaderT Config (StateT XState IO) a)
    deriving (Functor, Monad, MonadIO, MonadState XState, MonadReader Config)

-- | The State component of StateT
data XState = 
    XState { display :: Display
           , window :: Window
           , vars :: [(ThreadId, MVar String)]
           }

-- | Totally useless: but it is nice to be able to use get to get the
-- state and ask to get the configuration: functions requires less
-- arguments, after all.
runXMobar :: Config -> [(ThreadId, MVar String)] -> Display -> Window -> Xbar () -> IO ()
runXMobar c v d w (X f) = 
    do runStateT (runReaderT f c) (XState d w v)
       return ()

-- | The event loop
eventLoop :: Xbar ()
eventLoop =
    do c <- ask
       s <- get
       i <- io $ readVariables (vars s)
       ps <- io $ parseString c i
       drawInWin ps
       -- back again: we are never ending
       io $ tenthSeconds (refresh c)
       eventLoop

-- | The function to create the initial window
createWin :: Config -> IO (Display, Window)
createWin config =
  do dpy   <- openDisplay ""
     let dflt = defaultScreen dpy
     rootw  <- rootWindow dpy dflt
     win <- mkUnmanagedWindow dpy (defaultScreenOfDisplay dpy) rootw 
            (fromIntegral $ xPos config) 
            (fromIntegral $ yPos config) 
            (fromIntegral $ width config) 
            (fromIntegral $ hight config)
     mapWindow dpy win
     return (dpy,win)


-- $print

-- | Draws in and updates the window
drawInWin :: [(String, String)] -> Xbar ()
drawInWin str = 
    do config <- ask
       st <- get
       let (dpy,win) = (display st, window st)
       bgcolor  <-  io $ initColor dpy $ bgColor config
       gc <- io $ createGC dpy win
       --let's get the fonts
       fontst <-  io $ loadQueryFont dpy (fonts config)
       io $ setFont dpy gc (fontFromFontStruct fontst)

       -- set window background 
       io $ setForeground dpy gc bgcolor
       io $ fillRectangle dpy win gc 0 0 
              (fromIntegral $ width config) 
              (fromIntegral $ hight config)
       -- write
       let strWithLenth = map (\(s,c) -> (s,c,textWidth fontst s)) str
       printStrings gc fontst 1 strWithLenth 
       -- free everything
       io $ freeFont dpy fontst
       io $ freeGC dpy gc
       io $ flush dpy

-- | An easy way to print the stuff we need to print
printStrings :: GC
             -> FontStruct
             -> Position
             -> [(String, String, Position)]
             -> Xbar ()
printStrings _ _ _ [] = return ()
printStrings gc fontst offs sl@((s,c,l):xs) =
    do config <- ask
       st <- get
       let (_,asc,_,_) = textExtents fontst s
           totSLen = foldr (\(_,_,len) -> (+) len) 0 sl
           valign = (fromIntegral (hight config) + fromIntegral asc) `div` 2
           offset = case (align config) of
                      "center" -> (fromIntegral (width config) - fromIntegral totSLen) `div` 2
                      "right" -> fromIntegral (width config) - fromIntegral totSLen
                      "left" -> offs
                      _ -> offs
       color <- io $ initColor (display st) c
       io $ setForeground (display st) gc color
       io $ drawString (display st) (window st) gc offset valign s
       printStrings gc fontst (offs + l) xs

-- $commands

-- | Gets the command options set in configuration.
getOptions :: Config -> String -> [String]
getOptions c com =
    let l = commands c
        p = filter (\(s,_,_) -> s == com) l
    in case p of
         [(_,_,opts)] -> opts
         _ -> []

-- | Gets the command options set in configuration.
getRefRate :: Config -> String -> Int
getRefRate c com =
    let l = commands c
        p = filter (\(s,_,_) -> s == com) l
    in case p of
         [(_,int,_)] -> int
         _ -> refresh c

-- | Runs a list of programs
execCommands :: Config -> [(String,String,String)] -> IO [(ThreadId, MVar String)]
execCommands _ [] = return []
execCommands c (x:xs) =
    do i <- execCommand c x
       is <- execCommands c xs
       return $ i : is

execCommand :: Config -> (String,String,String) -> IO (ThreadId, MVar String)
execCommand c com = 
    do var <- newMVar "Updating..."
       h <- forkIO $ runCommandLoop var c com
       return (h,var)

-- | Runs the external program
runCommandLoop :: MVar String -> Config -> (String,String,String) -> IO ()
runCommandLoop var conf c@(s,com,ss) 
    | com == "" = 
        do modifyMVar_ var (\_ -> return $ "Could not parse the template")
           tenthSeconds (refresh conf)
           runCommandLoop var conf c
    | otherwise =
        do (i,o,e,p) <- runInteractiveCommand (com ++ concat (map (' ':) $ getOptions conf com))
           -- the followinf leaks memory
           --(i,o,e,p) <- runInteractiveProcess com (getOptions c com) Nothing Nothing
           exit <- waitForProcess p
           let closeHandles = do hClose o
                                 hClose i
                                 hClose e
           case exit of
             ExitSuccess -> do str <- hGetLine o
                               closeHandles
                               modifyMVar_ var (\_ -> return $ s ++ str ++ ss)
                               tenthSeconds (getRefRate conf com)
                               runCommandLoop var conf c
             _ -> do closeHandles
                     modifyMVar_ var $ \_ -> return $ "Could not execute command " ++ com
                     tenthSeconds (getRefRate conf com)
                     runCommandLoop var conf c
                                  

-- | Reads MVars set by 'runCommandLoop'
readVariables :: [(ThreadId, MVar String)] -> IO String
readVariables [] = return ""
readVariables ((_,v):xs) =
    do f <- readMVar v
       fs <- readVariables xs
       return $! f ++ fs

{- $unmanwin

This is a way to create unmamaged window. It was a mistery in Haskell. 
Till I've found out...;-)

-}

-- | Creates a window with the attribute override_redirect set to True.
-- Windows Managers should not touch this kind of windows.
mkUnmanagedWindow :: Display
                  -> Screen
                  -> Window
                  -> Position
                  -> Position
                  -> Dimension
                  -> Dimension
                  -> IO Window
mkUnmanagedWindow dpy scr rw x y w h = do
  let visual = defaultVisualOfScreen scr
      attrmask = cWOverrideRedirect
  win <- allocaSetWindowAttributes $ 
         \attributes -> do
           set_override_redirect attributes True
           createWindow dpy rw x y w h 0 (defaultDepthOfScreen scr) 
                        inputOutput visual attrmask attributes                                
  return win

{- $utility
Utilities, aka stollen without givin' credit stuff.
-}

-- | Get the Pixel value for a named color
initColor :: Display -> String -> IO Pixel
initColor dpy c = (color_pixel . fst) `liftM` allocNamedColor dpy colormap c
    where colormap = defaultColormap dpy (defaultScreen dpy)

-- | Short-hand for lifting in the IO monad
io :: IO a -> Xbar a
io = liftIO

-- | Work arount to the Int max bound: since threadDelay takes an Int, it
-- is not possible to set a thread delay grater than about 45 minutes.
-- With a little recursion we solve the problem.
tenthSeconds :: Int -> IO ()
tenthSeconds s | s >= x = do threadDelay y
                             tenthSeconds (x - s)
               | otherwise = threadDelay (s * 100000)
               where y = (maxBound :: Int)
                     x = y `div` 100000