Merge pull request #15 from skinner33/master

Brightness Monitor Plugin

1 files changed, 118 insertions, 0 deletions

diff --git a/src/Plugins/Monitors/Bright.hs b/src/Plugins/Monitors/Bright.hs
new file mode 100644
index 0000000..499e5bc
--- /dev/null
+++ b/src/Plugins/Monitors/Bright.hs
@@ -0,0 +1,118 @@
+-----------------------------------------------------------------------------
+---- |
+---- Module      :  Plugins.Monitors.Birght
+---- Copyright   :  (c) Martin Perner
+---- License     :  BSD-style (see LICENSE)
+----
+---- Maintainer  :  Martin Perner <martin@perner.cc>
+---- Stability   :  unstable
+---- Portability :  unportable
+----
+----  A screen brightness monitor for Xmobar
+----
+-------------------------------------------------------------------------------
+
+module Plugins.Monitors.Bright (brightConfig, runBright) where
+
+import Plugins.Monitors.Common
+import qualified Data.ByteString.Lazy.Char8 as B
+import Data.Char
+import System.FilePath ((</>))
+import System.Posix.Files (fileExist)
+import System.Console.GetOpt
+
+data BrightOpts = BrightOpts
+	{ subDir :: String
+	, currBright :: String
+	, maxBright :: String
+	}
+
+defaultOpts :: BrightOpts
+defaultOpts = BrightOpts
+	{ subDir = "acpi_video0"
+	, currBright = "actual_brightness"
+	, maxBright = "max_brightness"
+	}
+
+options :: [OptDescr (BrightOpts -> BrightOpts)]
+options =
+	[ Option "D" ["device"] (ReqArg (\x o -> o { subDir = x }) "") ""
+	, Option "C" ["curr"] (ReqArg (\x o -> o { currBright = x }) "") ""
+	, Option "M" ["max"] (ReqArg (\x o -> o { maxBright = x }) "") ""
+	]
+
+-- from Batt.hs
+parseOpts :: [String] -> IO BrightOpts
+parseOpts argv =
+	case getOpt Permute options argv of
+		(o, _, []) -> return $ foldr id defaultOpts o
+		(_, _, errs) -> ioError . userError $ concat errs
+
+sysDir :: FilePath
+sysDir = "/sys/class/backlight/"
+
+brightConfig :: IO MConfig
+brightConfig = mkMConfig
+		"<percent>" -- template
+		["hbar", "percent", "bar"] -- replacements
+
+data Files = Files
+	{ fCurr :: String
+	, fMax :: String
+	} | NoFiles
+
+brightFiles :: BrightOpts -> IO Files
+brightFiles opts =
+	do
+		is_curr <- fileExist $ (fCurr files)
+		is_max  <- fileExist $ (fCurr files)
+		if is_curr && is_max
+			then return files
+			else return NoFiles
+	where
+		prefix = sysDir </> (subDir opts)
+		files = Files { fCurr = prefix </> (currBright opts)
+		              , fMax = prefix </> (maxBright opts)
+		              }
+
+
+runBright :: [String] ->  Monitor String
+runBright args = do
+	opts <- io $ parseOpts args
+	f <- io $ brightFiles opts
+	c <- io $ readBright f
+	case f of
+		NoFiles -> return "hurz"
+		_ -> do x <- fmtPercent c
+			parseTemplate (x)
+	where
+		fmtPercent :: Float -> Monitor [String]
+		fmtPercent c = do
+			r <- showHorizontalBar (100 * c)
+			s <- showPercentWithColors c
+			t <- showPercentBar (100 * c) c
+			return [r,s,t]
+
+readBright :: Files -> IO Float
+readBright NoFiles = return 0
+readBright files =
+	do
+		currVal<- grab $ (fCurr files)
+		maxVal <- grab $ (fMax files)
+		return $ (currVal / maxVal) 
+	where
+		grab f = catch (fmap (read . B.unpack) $ B.readFile f)(\_ -> return 0)
+
+
+showHorizontalBar :: Float -> Monitor String
+showHorizontalBar x = do
+	return $ [convert x]
+	where
+		convert :: Float -> Char
+		convert val 
+			| t <= 9600 = ' '
+			| t > 9608 = chr 9608
+			| otherwise = chr t
+			where
+				-- we scale from 0 to 100, we have 8 slots (9 elements), 100/8 = 12
+				t = 9600 + ((round val) `div` 12)