diff --git a/Example1.hs b/Example1.hs
new file mode 100644
--- /dev/null
+++ b/Example1.hs
@@ -0,0 +1,19 @@
+import Data.Time
+import System.Dzen
+import System.Locale
+
+printer :: Printer (String, ZonedTime)
+printer = str "Wndn: " +++ cstr +++ str " - " +++ simple' format
+ where format = formatTime defaultTimeLocale "%a %e %b %H:%M:%S"
+
+supply :: IO (String, ZonedTime)
+supply = getCurrentWindow ## getZonedTime
+
+myDzen :: IO ()
+myDzen = runDzen "dzen2" [] 500 printer supply
+
+getCurrentWindow :: IO String
+getCurrentWindow = return "My =^.^= Lolcats"
+
+main :: IO ()
+main = myDzen
diff --git a/Example2.hs b/Example2.hs
new file mode 100644
--- /dev/null
+++ b/Example2.hs
@@ -0,0 +1,37 @@
+import Data.Monoid
+import Data.Time
+import System.Dzen
+import System.Locale
+
+sep :: DString
+sep = mconcat [str " ", rectO 5 5, str " "]
+
+timeBar :: Printer Int
+timeBar = cgdbar False (40,10) Nothing Nothing True (0, 60*60-1)
+
+zonedSecs :: ZonedTime -> Int
+zonedSecs = extract . localTimeOfDay . zonedTimeToLocalTime
+ where extract t = let minutes = fromIntegral (todMin t)
+ in round (minutes * 60 + todSec t)
+
+timeBar' :: Printer ZonedTime
+timeBar' = comap zonedSecs timeBar
+
+time :: Printer ZonedTime
+time = simple' format +=+ timeBar'
+ where format = formatTime defaultTimeLocale "%a %e %b %H:"
+
+printer :: Printer (String, ZonedTime)
+printer = str "Wndn: " +++ cstr +++ sep +++ time
+
+supply :: IO (String, ZonedTime)
+supply = getCurrentWindow ## getZonedTime
+
+myDzen :: IO ()
+myDzen = runDzen "dzen2" [] 500 printer supply
+
+getCurrentWindow :: IO String
+getCurrentWindow = return "My =^.^= Lolcats"
+
+main :: IO ()
+main = myDzen
diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,674 @@
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+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation. If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+ If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+ Later license versions may give you additional or different
+permissions. However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+ 15. Disclaimer of Warranty.
+
+ THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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+IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+ 16. Limitation of Liability.
+
+ IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+
+ Copyright (C)
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see .
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+ Copyright (C)
+ This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+.
+
+ The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+.
diff --git a/Setup.lhs b/Setup.lhs
new file mode 100644
--- /dev/null
+++ b/Setup.lhs
@@ -0,0 +1,8 @@
+#!/usr/bin/env runhaskell
+
+> module Main (main) where
+>
+> import Distribution.Simple
+>
+> main :: IO ()
+> main = defaultMain
diff --git a/System/Dzen.hs b/System/Dzen.hs
new file mode 100644
--- /dev/null
+++ b/System/Dzen.hs
@@ -0,0 +1,290 @@
+-- |
+-- Module : System.Dzen
+-- Copyright : (c) 2009 Felipe A. Lessa
+-- License : GPL 3 (see the LICENSE file in the distribution)
+--
+-- Maintainer : felipe.lessa@gmail.com
+-- Stability : experimental
+-- Portability : semi-portable (uses MPTC and type families)
+--
+-- Hello!
+--
+-- This is @dzen-utils@' main module. It re-exports every other
+-- module from this library, so you may just say
+--
+-- > import System.Dzen
+--
+-- and you'll have everything in hand. To learn more about this
+-- library, please see the documentation of each module exported here.
+-- To get you started, there are some simple examples below. :)
+
+module System.Dzen
+ (-- * Example 1
+ -- $example1p1
+
+ -- ** Constructing - Part 1
+ -- $example1p2
+
+ -- ** Constructing - Part 2
+ -- $example1p3
+
+ -- ** Applying
+ -- $example1p4
+
+ -- ** Whole code
+ -- $example1p5
+
+
+
+ -- * Example 2
+ -- $example2p1
+
+ -- ** Separator
+ -- $example2p2
+
+ -- ** Time bar
+ -- $example2p3
+
+ -- ** Glueing the time text with the bar
+ -- $example2p4
+
+ -- ** Whole code
+ -- $example2p5
+
+
+ -- * Module exports
+ module System.Dzen.Base
+ ,module System.Dzen.Colour
+ ,module System.Dzen.Graphics
+ ,module System.Dzen.Padding
+ ,module System.Dzen.Bars
+ ,module System.Dzen.Process
+ ) where
+
+import System.Dzen.Base
+import System.Dzen.Colour
+import System.Dzen.Graphics
+import System.Dzen.Padding
+import System.Dzen.Bars
+import System.Dzen.Process
+
+
+-- $example1p1
+--
+-- Suppose you have
+--
+-- > import Data.Time
+-- > import System.Locale
+-- >
+-- > getZonedTime :: IO ZonedTime -- from time package
+-- > getCurrentWindow :: IO String -- from somewhere you know :)
+--
+-- and that you want your bar to look like
+--
+-- > "Wndw: [my window title here] - Sun 15 Mar 07:10:02"
+--
+-- Okay, that's pretty nice. What you will do first will be to
+-- construct the 'Printer' of your bar. Basically, what you want is to
+-- concatenate @\"Wndw: \"@, the result of @getCurrentWindow@, the
+-- separator, and the formated result of @getZonedTime@. The @Printer@
+-- we'll build below contain all the information necessary to create
+-- the final output string above from the two @get@ functions!
+
+
+-- $example1p2
+--
+-- To write the constant strings, we use 'str':
+--
+-- > str :: String -> DString
+-- > str "Wndw: " :: DString
+-- > str " - " :: DString
+--
+-- That is pretty straightforward. But how can we print the current
+-- window? We will just use 'cstr' here
+--
+-- > cstr :: Printer String
+--
+-- While @str@ is used as a common function, you just apply the
+-- string you want to it, @cstr@ will get the string from another
+-- source. What we'll do shortly is to pipe @IO String@ into
+-- @Printer String@ to obtain our final output. Instead of
+-- @Printer a@, think of it as @Printer input@.
+--
+-- To concatenate we just have to use '+++' from 'Combine', which
+-- is an ugly class used to create beautiful types:
+--
+-- > str "Wndn: " +++ cstr +++ str " - " :: Printer String
+--
+-- Whenever you concatenate a @DString@ with a @Printer input@, you
+-- get a @Printer input@ as a result. That is, if you concatenate a
+-- constant string to something that takes an input and produces a
+-- string, what you get is something that takes an input and produces
+-- the concatenated string. Note that you don't need to write the
+-- type above.
+
+-- $example1p3
+--
+-- Now we can't just go ahead and use @cstr@ directly with
+-- @getZonedTime@ because, unlike @getCurrentWindow@, its result is
+-- not a string, but a @ZonedTime@. To format the @ZonedTime@ is
+-- outside the scope of this example, but you can get the format
+-- shown above with
+--
+-- > format :: ZonedTime -> String
+-- > format = formatTime defaultTimeLocale "%a %e %b %H:%M:%S"
+--
+-- While you can write
+--
+-- > fmap format getZoneTime :: IO String
+--
+-- you don't need to push the format function into the @IO@ monad,
+-- just put it in the @Printer@, the place where it belongs! To
+-- accomplish that use 'simple'' instead of 'cstr':
+--
+-- > simple' :: (input -> String) -> Printer input
+-- > simple' format :: Printer ZonedTime
+--
+-- And it's done! Concatenating everything:
+--
+-- > printer :: Printer (String, ZonedTime)
+-- > printer = str "Wndn: " +++ cstr +++ str " - " +++ simple' format
+--
+-- Whenever you concatenate @Printer a@ with @Printer b@ you
+-- get @Printer (a,b)@.
+
+-- $example1p4
+--
+-- In the end we just want strings, not @Printer@s, so we need to
+-- apply our @printer@ to some inputs. We already have functions for
+-- each part of our input, but we need to combine them. We may just
+-- use @##@ from "System.Dzen.Process" in this case (and in most others as
+-- well):
+--
+-- > supply :: IO (String, ZonedTime)
+-- > supply = getCurrentWindow ## getZonedTime
+--
+-- Now we could use 'apply', 'applyMany' or 'applyForever' to
+-- get strings out of our printer, but we'll use 'runDzen' directly
+-- which is a tad easier:
+--
+-- > myDzen :: IO ()
+-- > myDzen = runDzen "dzen2" [] 500 printer supply
+--
+-- And that's it! You may use @myDzen@ directly as @main@, or you
+-- may use @forkIO myDzen@ inside @xmonad@. Pretty nice, uh?
+
+-- $example1p5
+--
+-- This is the whole code plus a stub @getCurrentWindow@ and a @main@.
+-- We omit the signatures on purpose to show how you could have
+-- written it lazily. You may also get the file @Example1.hs@ from the
+-- source code which contains all the type signatures.
+--
+-- >import Data.Time
+-- >import System.Dzen
+-- >import System.Locale
+-- >
+-- >printer = str "Wndn: " +++ cstr +++ str " - " +++ simple' format
+-- >format = formatTime defaultTimeLocale "%a %e %b %H:%M:%S"
+-- >supply = getCurrentWindow ## getZonedTime
+-- >myDzen = runDzen "dzen2" [] 500 printer supply
+-- >
+-- >getCurrentWindow = return "My =^.^= Lolcats"
+-- >main = myDzen
+
+
+
+
+
+-- $example2p1
+--
+-- Now we want to do something different: let's have a graphical
+-- bar for our clock! And, why not, a graphical separator.
+
+-- $example2p2
+--
+-- The graphical separator will be very simple. Instead of dash
+-- (@\" - \"@) we'll use a small dot:
+--
+-- > import Data.Monoid
+-- >
+-- > sep :: DString
+-- > sep = mconcat [pos 4, rect 3 3, pos 4]
+--
+-- This is a 3x3 rectangle with 4 pixels of spacing on each side.
+-- And, thats it!
+
+-- $example2p3
+--
+-- Now something more challenging. Instead of showing the minutes
+-- and the seconds, we want to show a graphical bar, something like
+--
+-- > "Wndw: [my window title here] - Sun 15 Mar 07:[== ]"
+--
+-- Well, that bar will show minutes and seconds, but we can
+-- take as input just seconds, ranging from @0@ to @60*60-1@.
+-- We'll use plain simple 'cgdbar', which mimics @gdbar@:
+-- (please look at "System.Dzen.Bars" for more info)
+--
+-- > timeBar :: Printer Int
+-- > timeBar = cgdbar False (40,10) Nothing Nothing True (0, 60*60-1)
+--
+-- But what we have is not the number of seconds, but a @ZonedTime@.
+-- So we need
+--
+-- > zonedSecs :: ZonedTime -> Int
+-- > zonedSecs = extract . localTimeOfDay . zonedTimeToLocalTime
+-- > where extract t = let minutes = fromIntegral (todMin t)
+-- > in round (minutes * 60 + todSec t)
+--
+-- As @Printer@s are cofunctors, we can use 'comap' to get
+-- a suitable @timeBar@:
+--
+-- > timeBar' :: Printer ZonedTime
+-- > timeBar' = comap zonedSecs timeBar
+
+-- $example2p4
+--
+-- We also want the rest of the time, not just the bar. First,
+-- we need a new @format@, as we don't want to show the minutes
+-- anymore:
+--
+-- > format :: ZonedTime -> String
+-- > format = formatTime defaultTimeLocale "%a %e %b %H:"
+--
+-- You may be tempted to write @simple' format +++ timeBar'@ now,
+-- but there's a small glitch: it would have type
+-- @Printer (ZonedTime, ZonedTime)@, but we want both to use
+-- the same @ZonedTime@. We could use 'comap' again or 'combine',
+-- but it is easier to write
+--
+-- > time :: Printer ZonedTime
+-- > time = simple' format +=+ timeBar'
+
+-- $example2p5
+--
+-- The rest is just glue! So we now present the whole code,
+-- again in a compact form. See @Example2.hs@ for the whole
+-- code with type signatures:
+--
+-- >import Data.Monoid
+-- >import Data.Time
+-- >import System.Dzen
+-- >import System.Locale
+-- >
+-- >zonedSecs = extract . localTimeOfDay . zonedTimeToLocalTime
+-- > where extract t = let minutes = fromIntegral (todMin t)
+-- > in round (minutes * 60 + todSec t)
+-- >
+-- >time = simple' format +=+ comap zonedSecs timeBar
+-- > where format = formatTime defaultTimeLocale "%a %e %b %H:"
+-- > timeBar = cgdbar False (40,10) Nothing Nothing True (0, 60*60-1)
+-- >
+-- >printer = str "Wndn: " +++ cstr +++ sep +++ time
+-- > where sep = mconcat [str " ", rectO 5 5, str " "]
+-- >
+-- >supply = getCurrentWindow ## getZonedTime
+-- >myDzen = runDzen "dzen2" [] 500 printer supply
+-- >
+-- >getCurrentWindow = return "My =^.^= Lolcats"
+-- >main = myDzen
diff --git a/System/Dzen/Bars.hs b/System/Dzen/Bars.hs
new file mode 100644
--- /dev/null
+++ b/System/Dzen/Bars.hs
@@ -0,0 +1,295 @@
+-- |
+-- Module : System.Dzen.Bars
+-- Copyright : (c) 2009 Felipe A. Lessa
+-- License : GPL 3 (see the LICENSE file in the distribution)
+--
+-- Maintainer : felipe.lessa@gmail.com
+-- Stability : experimental
+-- Portability : semi-portable (uses MPTC and type families)
+--
+-- Drawing of progress bars (sometimes called progress gauges),
+-- like @dbar@ and @gdbar@ utilities work but a little more
+-- powerful (in fact, we can simulate both utilities, see 'dbar'
+-- and 'gdbar').
+--
+-- An example of text progress bar that can be drawn:
+--
+-- > 96% [==================> ]
+
+module System.Dzen.Bars
+ (-- * Simple interface
+ -- ** Mimicking @dbar@
+ dbar
+ ,cdbar
+ -- ** Mimicking @gdbar@
+ ,gdbar
+ ,cgdbar
+
+ -- * Generic interface
+ ,bar
+ ,cbar
+ ,BarType(..)
+ ,BarTextType(..)
+ ,BarText(..)
+
+ -- * Styles of the simple interfaces
+ -- You may want to use some of these as the
+ -- base for your own style. Look at the sources!
+ ,dbar_style
+ ,gdbar_style
+ ) where
+
+import Control.Arrow
+import Data.Monoid
+import System.Dzen.Base
+import System.Dzen.Colour
+import System.Dzen.Graphics
+import System.Dzen.Padding
+
+-- | Helper function used below.
+maybeLeft :: Bool -> BarText
+maybeLeft False = None
+maybeLeft True = AtLeft Percentage
+
+-- | Mimics the dbar utility. Uses the 'dbar_style'.
+dbar :: (Num a, Enum a, Ord a)
+ => Bool -- ^ If @True@, write the percentage on the left.
+ -> Width -- ^ Width of the bar interior.
+ -> (a,a) -- ^ Minimum and maximum values.
+ -> a -- ^ Actual value.
+ -> DString
+dbar p = bar (maybeLeft p) . dbar_style '='
+
+-- | Mimics the dbar utility while getting the input dinamically.
+cdbar :: (Num a, Enum a, Ord a) => Bool -> Width -> (a,a) -> Printer a
+cdbar p = cbar (maybeLeft p) . dbar_style '='
+
+-- | The style produced by the dbar utility.
+dbar_style :: Char -> Width -> BarType
+dbar_style c w = Text {txtOpen = "["
+ ,txtFilled = str [c]
+ ,txtMiddle = Nothing
+ ,txtBackground = " "
+ ,txtClose = "]"
+ ,txtWidth = w}
+
+-- | Mimics the gdbar utility. Uses the 'gdbar_style'.
+gdbar :: (Num a, Enum a, Ord a)
+ => Bool -- ^ If @True@, write the percentage on the left.
+ -> (Width, Height) -- ^ Size of the whole bar (excluding text).
+ -> Maybe DColour -- ^ Filled colour (see 'grpFilled').
+ -> Maybe DColour -- ^ Background/border colour
+ -- (see 'grpBackground' and 'grpBorder').
+ -> Bool -- ^ @True@ to mimic @-o@ option (outline).
+ -> (a,a) -- ^ Minimum and maximum values.
+ -> a -- ^ Actual value.
+ -> DString
+gdbar p = (((bar (maybeLeft p) .) . ) .) . gdbar_style
+
+-- | Mimics the gdbar utility while getting the input dinamically.
+cgdbar :: (Num a, Enum a, Ord a) => Bool -> (Width, Height)
+ -> Maybe DColour -> Maybe DColour -> Bool -> (a,a) -> Printer a
+cgdbar p = (((cbar (maybeLeft p) .) . ) .) . gdbar_style
+
+-- | The style of gdbar (or something very close).
+gdbar_style :: (Width, Height) -> Maybe DColour
+ -> Maybe DColour -> Bool -> BarType
+gdbar_style size_ fore back False =
+ Filled {grpFilled = fore
+ ,grpBackground = back
+ ,grpSize = size_}
+gdbar_style size_ fore back True =
+ Hollow {grpFilled = fore
+ ,grpBackground = Nothing -- That's what gdbar does!
+ ,grpBorder = back
+ ,grpSize = size_}
+
+
+
+
+
+
+
+
+-- | The type of the bar to be drawn.
+data BarType = -- | Draws a text bar. Note, however, that the
+ -- @DString@s below can be anything, not just
+ -- text. For example, they may have colours ('fg'),
+ -- shapes ('rect's and 'circ's) or 'icon's, you may
+ -- even simulate both 'Filled' and 'Hollow' using just
+ -- 'Text' (although performance would be suboptimal).
+ Text {
+ -- | Text written at the start.
+ txtOpen :: !DString
+ -- | Text written for each filled square.
+ ,txtFilled :: !DString
+ -- | Text written for the last filled square.
+ -- If @Nothing@, the same as the filled square
+ -- is used, but more fairly than if you used
+ -- the same value for filled and middle chars.
+ ,txtMiddle :: !(Maybe DString)
+ -- | Text written for the unfilled squares.
+ ,txtBackground :: !DString
+ -- | Text written at the end.
+ ,txtClose :: !DString
+ -- | How many squares there should be
+ -- (i.e. does not count the open and close parts).
+ ,txtWidth :: !Width}
+
+ -- | Draws a filled graphical bar, like @gdbar@ would.
+ | Filled {
+ -- | Colour used for filled squares, or @Nothing@
+ -- to use the default /foreground/ colour.
+ grpFilled :: !(Maybe DColour)
+ -- | Colour used for the unfilled squares, or
+ -- @Nothing@ to use the default /background/
+ -- colour.
+ ,grpBackground :: !(Maybe DColour)
+ -- | Size of the whole bar.
+ ,grpSize :: !(Width, Height)}
+
+ -- | Draws a filled graphical bar with a surrounding
+ -- border.
+ | Hollow {
+ -- | Same as @grpFilled@ above.
+ grpFilled :: !(Maybe DColour)
+ -- | Same as @grpBackground@ above.
+ ,grpBackground :: !(Maybe DColour)
+ -- | Colour of the border, or @Nothing@ to use
+ -- the default /foreground/ colour.
+ ,grpBorder :: !(Maybe DColour)
+ -- | Size of the whole bar (including border).
+ ,grpSize :: !(Width, Height)}
+ deriving (Show)
+
+-- | The type of text to be written.
+data BarTextType = Percentage | Absolute
+ deriving (Eq, Ord, Show, Enum)
+
+-- | How to draw the bar text. @AtLeft@ and @AtRight@ are used to
+-- specify if the text is at the left or the right of the bar,
+-- and @None@ means that no text will be written.
+data BarText = AtLeft !BarTextType
+ | AtRight !BarTextType
+ | None
+ deriving (Eq, Ord, Show)
+
+
+-- | Draws a bar and optionally some text describing some quantity
+-- in relation to some range. For example,
+--
+-- > bar (AtLeft Percentage) (Text "[" "=" (Just ">") " " "]" 20) (-10,10) i
+--
+-- produces the bars
+--
+-- > " 2% [ ]" where i = -9.6
+-- > " 2% [> ]" where i = -9.5
+-- > " 50% [=========> ]" where i = 0
+-- > " 96% [==================> ]" where i = 9.4
+-- > " 99% [===================>]" where i = 9.99
+-- > "100% [====================]" where i = 10
+--
+-- Note that the text is always padded to four characters. If the
+-- first bar above had @AtRight Percentage@ the result would be
+--
+-- > "[ ] 2% "
+--
+-- so the padding always inserts the spaces on the outside.
+bar :: (Num a, Enum a, Ord a) => BarText ->
+ BarType -> (a,a) -> a -> DString
+bar txt bar_ r v =
+ case txt of
+ None -> drawnBar
+ AtLeft t -> mconcat [padL 4 (barText t r v), " ", drawnBar]
+ AtRight t -> mconcat [drawnBar, " ", padR 4 (barText t r v)]
+ where drawnBar = barDraw bar_ r v
+
+-- | 'bar' wrapped with 'simple' so that the value is
+-- taken from an input.
+cbar :: (Num a, Enum a, Ord a) => BarText ->
+ BarType -> (a,a) -> Printer a
+cbar = ((simple .) .) . bar
+
+
+-- | Draws the text part of the bar.
+barText :: (Num a, Enum a, Ord a) => BarTextType -> (a,a) -> a -> DString
+barText Absolute _ val = str $ show val
+barText Percentage range val
+ = str $ (show . fst . fst $ barRound 100 range val) ++ "%"
+{-# INLINE barText #-}
+
+
+-- | Draws the bar itself.
+barDraw :: (Num a, Enum a, Ord a) => BarType -> (a,a) -> a -> DString
+barDraw (Text {txtOpen = to
+ ,txtFilled = tf
+ ,txtMiddle = Just tm -- <<<<<<<<
+ ,txtBackground = tb
+ ,txtClose = tc
+ ,txtWidth = tw}) range val
+ = let ((f, b), more) = barRound tw range val
+ r | f >= tw = to : replicate tw tf
+ | f > 0 = to : replicate f' tf ++ tm : replicate b' tb
+ | more = to : tm : replicate (tw-1) tb
+ | True = to : replicate tw tb
+ where (f',b') | more = (f, b-1)
+ | otherwise = (f-1, b)
+ in mconcat r `mappend` tc
+
+barDraw (Text {txtOpen = to
+ ,txtFilled = tf
+ ,txtMiddle = Nothing -- <<<<<<<<
+ ,txtBackground = tb
+ ,txtClose = tc
+ ,txtWidth = tw}) range val
+ = let (f, b) = fst $ barRound tw range val
+ r = to : replicate f tf ++ replicate b tb
+ in mconcat r `mappend` tc
+
+barDraw (Filled {grpFilled = gf
+ ,grpBackground = gb
+ ,grpSize = (gw,gh)}) range val
+ = let (f, b) = fst $ barRound gw range val
+ in mconcat $ [changeFg gf $ rect f gh
+ ,transpRect gb b gh]
+
+barDraw (Hollow {grpFilled = gf
+ ,grpBackground = gb
+ ,grpBorder = gbd
+ ,grpSize = (gw_orig, gh_orig)}) range val
+ = let gw = gw_orig - 4 -- Account for the border
+ gh = gh_orig - 4
+ (f, b) = fst $ barRound gw range val
+ in mconcat $ [pos 2
+ ,changeFg gf $ rect f gh
+ ,transpRect gb b gh
+ ,pos $ negate (gw + 2)
+ ,changeFg gbd $
+ ignoreBg True $
+ rectO gw_orig gh_orig]
+{-# INLINE barDraw #-}
+
+-- | Simulates transparency by not drawing at all.
+transpRect :: Maybe DColour -> Width -> Height -> DString
+transpRect Nothing w _ = pos w
+transpRect (Just c) w h = fg c $ rect w h
+
+
+-- | Function used for rounding. It always rounds towards minus
+-- infinity, so only the maximum value gives a full bar.
+-- Values outside the range are clamped. The boolean returned
+-- is @True@ iff the value would be one more if we rounded
+-- half-up.
+barRound :: (Num a, Enum a, Ord a) =>
+ Width -> (a,a) -> a -> ((Int, Int), Bool)
+barRound w r n = let (f, b) = barRound' w r n in ((f, w - f), b)
+
+barRound' :: (Num a, Enum a, Ord a) =>
+ Width -> (a,a) -> a -> (Int, Bool)
+barRound' w (mini,maxi) n
+ | maxi < mini = error "System.Dzen.Bars.bar: max value is less than min."
+ | n <= mini = (0, False)
+ | n >= maxi = (w, False)
+ | otherwise = let r = fromEnum (2 * fromIntegral w * (n-mini))
+ `div` fromEnum (maxi-mini)
+ in second (== 1) (r `divMod` 2)
diff --git a/System/Dzen/Base.hs b/System/Dzen/Base.hs
new file mode 100644
--- /dev/null
+++ b/System/Dzen/Base.hs
@@ -0,0 +1,294 @@
+-- |
+-- Module : System.Dzen.Base
+-- Copyright : (c) 2009 Felipe A. Lessa
+-- License : GPL 3 (see the LICENSE file in the distribution)
+--
+-- Maintainer : felipe.lessa@gmail.com
+-- Stability : experimental
+-- Portability : semi-portable (MPTC and type families)
+--
+-- This module contains most of the basic functions of
+-- this package. The data types presented here are:
+--
+-- ['DString'] strings that support constant time concatenation,
+-- dzen attributes and some instropection.
+--
+-- ['Printer'] encapsulates functions take take some input and
+-- produce a @DString@ as a result, allowing them to be
+-- combined and applied.
+
+module System.Dzen.Base
+ (-- * Dzen Strings
+ DString
+ ,str
+ ,rawStr
+ ,toString
+ ,size
+ ,parens
+
+ -- * Printers
+ ,Printer
+ ,comap
+ ,simple
+ ,simple'
+ ,inputPrinter
+ ,inputPrinter'
+ ,cstr
+ ,cshow
+
+ -- * Combining printers
+ ,Combine(..)
+ -- $combine
+ ,(+=+)
+ ,(+-+)
+ ,(+/+)
+ ,(+<+)
+ ,combine
+
+ -- * Applying printers
+ -- $apply
+ ,apply
+ ,applyMany
+ ,applyMany_
+ ,applyForever
+
+ -- * Transforming
+ ,Transform(transform)
+ ) where
+
+import Prelude hiding ((++))
+import Control.Arrow hiding ((+++))
+import Data.Function
+import Data.String
+import Data.Monoid
+
+import System.Dzen.Internal
+
+
+
+
+
+-- | Converts a @String@ into a @DString@, escaping characters if
+-- needed. This function is used in 'fromString' from 'IsString',
+-- so @DString@s created by @OverloadedStrings@ extension will
+-- be escaped.
+str :: String -> DString
+str = fromString
+
+-- | Used internally, use 'mappend'.
+(++) :: Monoid a => a -> a -> a
+(++) = mappend
+
+-- | @parens open close d@ is equivalent to @mconcat [open, d, close]@.
+parens :: DString -> DString -> DString -> DString
+parens open close d = open ++ d ++ close
+
+
+
+
+
+
+
+-- | A @Printer@ is a cofunctor.
+comap :: (a -> b) -> (Printer b -> Printer a)
+comap f (P dp) = P $ \st input -> let (out,dp') = dp st (f input)
+ in (out, comap f dp')
+
+-- | Constructs a @Printer@ that depends only on the input.
+simple :: (a -> DString) -> Printer a
+simple f = fix $ P . const . (. f) . flip (,)
+
+-- | Like 'simple', but using @String@s.
+simple' :: (a -> String) -> Printer a
+simple' = simple . (str .)
+
+-- | Constructs a @Printer@ that depends on the current
+-- and on the previous inputs.
+inputPrinter :: (b -> a -> (DString, b)) -> b -> Printer a
+inputPrinter f b = P . const $ second (inputPrinter f) . f b
+
+-- | Like 'inputPrinter', but with @String@s.
+inputPrinter' :: (b -> a -> (String, b)) -> b -> Printer a
+inputPrinter' = inputPrinter . ((first str .) .)
+
+-- | Works like 'str', but uses the input instead of being
+-- constant. In fact, it is defined as @simple str@.
+cstr :: Printer String
+cstr = simple str
+
+-- | Same as @simple' show@.
+cshow :: Show a => Printer a
+cshow = simple' show
+
+
+
+
+
+
+
+
+
+-- | Class used for combining @DString@s and @Printer@s
+-- exactly like 'mappend'.
+--
+-- Note that we don't lift @DString@ to @Printer ()@ and use a
+-- plain function of type @Printer a -> Printer b
+-- -> Printer (a,b)@ because that would create types such as
+-- @Printer ((),(a,((),(b,()))))@ instead of
+-- @Printer (a,b)@.
+class Combine a b where
+ -- | The type of the combined input of @a@ with @b@.
+ type Combined a b :: *
+
+ -- | Combine @a@ into @b@. Their outputs are concatenated.
+ (+++) :: a -> b -> Combined a b
+
+infixr 4 +++
+infixr 4 +=+
+infixr 4 +-+
+infixr 4 +/+
+infixr 4 +<+
+
+instance Combine DString DString where
+ type Combined DString DString = DString
+ (+++) = (++)
+
+instance Combine DString (Printer a) where
+ type Combined DString (Printer a) = Printer a
+ ds1 +++ (P dp2) =
+ P $ \st input -> let (out2,dp2') = dp2 st input
+ in (ds1 ++ out2, ds1 +++ dp2')
+
+instance Combine (Printer a) DString where
+ type Combined (Printer a) DString = Printer a
+ (P dp1) +++ ds2 =
+ P $ \st input -> let (out1,dp1') = dp1 st input
+ in (out1 ++ ds2, dp1' +++ ds2)
+
+instance Combine (Printer a) (Printer b) where
+ type Combined (Printer a) (Printer b) = Printer (a,b)
+ (+++) = combine id
+
+-- $combine
+--
+-- We currently have the following @Combined@ types:
+--
+-- > type Combined DString Dstring = DString
+-- > type Combined DString (Printer a) = Printer a
+-- > type Combined (Printer a) DString = Printer a
+-- > type Combined (Printer a) (Printer b) = Printer (a,b)
+--
+-- For example, if @a :: DString@, @b,e :: Printer Int@,
+-- @c :: Printer Double@ and @d :: DString@, then
+--
+-- > (a +++ b +++ c +++ d +++ e) :: Printer (Int, (Double, Int))
+
+
+-- | Sometimes you want two printers having the same input,
+-- but @p1 +++ p2 :: Printer (a,a)@ is not convenient. So
+-- @p1 +=+ p2 :: Printer a@ works like '+++' but gives
+-- the same input for both printers.
+(+=+) :: Printer a -> Printer a -> Printer a
+(+=+) = combine (\x -> (x, x))
+
+-- | Works like '+=+' but the second printer's input is a tuple.
+(+-+) :: Printer a -> Printer (a,b) -> Printer (a,b)
+(+-+) = combine (\x -> (fst x, x))
+
+
+-- | While you may say @p1 +=+ (ds1 +++ ds2 +++ p2)@,
+-- where @p1,p2 :: Printer a@ and @ds1,ds2 :: DString@,
+-- you can't say @p1 +=+ (po +++ p2)@ nor
+-- @(p1 +++ po) +=+ p2@ where @po :: Printer b@.
+--
+-- This operator works like '+++' but shifts the
+-- tuple, giving you @Printer (b,a)@ instead of
+-- @Printer (a,b)@. In the example above you may
+-- write @p1 +>+ po +/+ p2@.
+(+/+) :: Printer a -> Printer b -> Printer (b,a)
+(+/+) = combine (\(a,b) -> (b,a))
+
+
+-- | This operator works like '+/+' but the second
+-- printer's input is a tuple. Use it like
+--
+-- > pA1 +-+ pB +<+ pC +<+ pD +/+ pA2 :: Printer (a,(b,(c,d)))
+--
+-- where both @pA1@ and @pA2@ are of type @Printer a@.
+(+<+) :: Printer a -> Printer (b,c) -> Printer (b,(a,c))
+(+<+) = combine (\(b,(a,c)) -> (a,(b,c)))
+
+
+-- | This is a general combine function for @Printer@s.
+-- The outputs are always concatenated, but the inputs
+-- are given by the supplied function.
+--
+-- The combining operators above are defined as:
+--
+-- > (+++) = combine id -- restricted to Printers
+-- > (+=+) = combine (\x -> ( x, x))
+-- > (+-+) = combine (\x -> (fst x, x))
+-- > (+/+) = combine (\(a,b) -> (b,a))
+-- > (+<+) = combine (\(b,(a,c)) -> (a,(b,c)))
+--
+-- Note also the resamblence with 'comap'. In fact,
+-- if we have @(+++)@ and @comap@ we may define
+--
+-- > combine f a b = comap f (a +++ b) -- pointwise
+-- > combine = flip (.) (+++) . (.) . comap -- pointfree
+--
+-- and with @combine@ and @simple@ we may define
+--
+-- > comap f = combine (\i -> ((), f i)) (simple $ const mempty) -- pointwise
+-- > comap = flip combine (simple $ const mempty) . ((,) () .) -- pointfree
+combine :: (c -> (a, b)) -> Printer a -> Printer b -> Printer c
+combine split = f
+ where f (P dp1) (P dp2) =
+ P $ \st input -> let (input1, input2) = split input
+ (out1, dp1') = dp1 st input1
+ (out2, dp2') = dp2 st input2
+ in (out1 ++ out2, f dp1' dp2')
+ -- Again, note how state is duplicated
+{-# INLINE combine #-}
+
+
+
+
+-- $apply
+--
+-- Note that applying should be the /last thing/ you do,
+-- and you should /never/ apply inside a 'DString'
+-- or 'Printer'. Doing so may cause undefined behaviour
+-- because both @DString@ and @Printer@ contain some internal
+-- state. We create a fresh internal state when applying,
+-- so applying inside them will not take their internal
+-- state into account. You've been warned!
+
+
+-- | Apply a printer many times in sequence. Most of the
+-- time you would ignore the final printer using
+-- 'applyMany_', but it can be used to continue applying.
+applyMany :: Printer a -> [a] -> ([String], Printer a)
+applyMany p (i:is) = let (s,p') = apply p i
+ rest = applyMany p' is
+ in (s : fst rest, snd rest)
+applyMany p [] = ([], p)
+
+
+-- | Like 'applyMany' but ignoring the final printer.
+applyMany_ :: Printer a -> [a] -> [String]
+applyMany_ p (i:is) = let (s,p') = apply p i in s : applyMany_ p' is
+applyMany_ _ [] = []
+
+
+-- | Apply a printer forever inside a monad. The first action
+-- is used as a supply of inputs while the second action
+-- receives the output before the next input is requested.
+--
+-- Note that your supply may be anything. For example,
+-- inside @IO@ you may use @threadDelay@:
+--
+-- > applyForever (threadDelay 100000 >> getInfo) (hPutStrLn dzenHandle)
+applyForever :: Monad m => Printer a -> m a -> (String -> m ()) -> m ()
+applyForever p get act = get >>= uncurry (>>) . (act *** f) . apply p
+ where f p' = applyForever p' get act
diff --git a/System/Dzen/Colour.hs b/System/Dzen/Colour.hs
new file mode 100644
--- /dev/null
+++ b/System/Dzen/Colour.hs
@@ -0,0 +1,108 @@
+-- |
+-- Module : System.Dzen.Colour
+-- Copyright : (c) 2009 Felipe A. Lessa
+-- License : GPL 3 (see the LICENSE file in the distribution)
+--
+-- Maintainer : felipe.lessa@gmail.com
+-- Stability : experimental
+-- Portability : semi-portable (uses MPTC and type families)
+--
+-- Support for colours. This module is entirely based on the @colour@
+-- package, so we strongly recommend that you at least
+--
+-- > import qualified Data.Colour.Names as C
+--
+-- which will import various aliases for creating 'Colour's.
+--
+-- Note changing the colours using the functions below do not hinder
+-- the use of automatic padding.
+
+module System.Dzen.Colour
+ (-- * Changing colours
+ DColour
+ ,fg
+ ,bg
+
+ -- * Reseting to the defaults
+ ,defFg
+ ,defBg
+
+ -- * Change or reset
+ ,changeFg
+ ,changeBg
+ ) where
+
+import Data.Colour.SRGB
+import System.Dzen.Base
+import System.Dzen.Internal
+
+
+
+
+-- | Set the foreground colour. Note that the foreground
+-- colour is changed only inside the transformed @DString@
+-- or @Printer@, unlike using @\"^fg\"@ which may affect
+-- subsequent strings.
+--
+-- So you may write
+-- @fg 'black' (fg 'lime' (str \"lime\") +++ str \"black\")@
+-- and it works like you expect it to.
+fg :: Transform a => DColour -> (a -> a)
+fg = changeFg . Just
+
+-- | Like 'fg', but set the background colour.
+bg :: Transform a => DColour -> (a -> a)
+bg = changeBg . Just
+
+
+
+
+-- | Set the foreground colour to be the default one,
+-- which is specified as a parameter to dzen (outside
+-- the control of the printers).
+defFg :: Transform a => a -> a
+defFg = changeFg Nothing
+
+-- | Like 'defFg', but for the background colour.
+defBg :: Transform a => a -> a
+defBg = changeBg Nothing
+
+
+
+
+-- | Set the foreground to be a specified one (@Just c@) or
+-- the dzen's default (@Nothing@). Both 'fg' and 'defFg'
+-- are specializations of this function.
+changeFg :: Transform a => Maybe DColour -> (a -> a)
+changeFg c = transformSt $ \st ->
+ if sFg st == c then (st, id)
+ else (st {sFg = c}, parensF showFg c (sFg st))
+
+-- | Like 'changeFg', but for the background colour.
+changeBg :: Transform a => Maybe DColour -> (a -> a)
+changeBg c = transformSt $ \st ->
+ if sBg st == c then (st, id)
+ else (st {sBg = c}, parensF showBg c (sBg st))
+
+
+
+
+
+
+-- Internal functions
+
+-- | 'parens' with steroids.
+parensF :: (a -> DString) -> a -> a -> DString -> DString
+parensF f = \a b -> parens (f a) (f b)
+
+-- | Change the foreground colour.
+showFg :: Maybe DColour -> DString
+showFg = mkCmd False "fg" . fromColour
+
+-- | Change the background colour.
+showBg :: Maybe DColour -> DString
+showBg = mkCmd False "bg" . fromColour
+
+-- | Lift 'sRGB24shows'.
+fromColour :: (RealFrac a, Floating a) => Maybe (Colour a) -> String
+fromColour = maybe "" sRGB24show
diff --git a/System/Dzen/Graphics.hs b/System/Dzen/Graphics.hs
new file mode 100644
--- /dev/null
+++ b/System/Dzen/Graphics.hs
@@ -0,0 +1,124 @@
+-- |
+-- Module : System.Dzen.Graphics
+-- Copyright : (c) 2009 Felipe A. Lessa
+-- License : GPL 3 (see the LICENSE file in the distribution)
+--
+-- Maintainer : felipe.lessa@gmail.com
+-- Stability : experimental
+-- Portability : semi-portable (uses MPTC and type families)
+--
+-- Support for the graphical abilities of @dzen@. Unfortunately
+-- this is not the strongest are of @dzen@, so there isn't a lot
+-- of functionality here, but there are \"bindings\" for every
+-- function they provide.
+--
+-- You can draw:
+--
+-- [icons] With 'icon' (see @dzen@ documentation about formats and paths).
+--
+-- [rectanges] With 'rect' and 'rectO'.
+--
+-- [circles] With 'circ' and 'circO'.
+--
+-- Although it may seem that you can draw anything with the rectangle
+-- primitive (i.e. in the worst case just use 1x1 rectangles to simulate
+-- pixels), @dzen@ does not allow you to control the @y@ part of the
+-- shapes, only the @x@ part (using 'pos' and 'absPos'): they are always
+-- vertically centered.
+
+module System.Dzen.Graphics
+ (-- * Data types
+ -- $dataTypes
+ Width
+ ,Height
+ ,Radius
+
+ -- * Icons
+ ,icon
+
+ -- * Shapes
+ ,rect
+ ,rectO
+ ,circ
+ ,circO
+
+ -- * Positioning
+ ,pos
+ ,absPos
+
+ -- * Misc
+ ,ignoreBg
+ )where
+
+import Data.Monoid
+import System.Dzen.Internal
+import System.Dzen.Base
+
+
+-- $dataTypes
+--
+-- These data types are used to hint the purpose of
+-- each argument, making the type signatures more clear.
+
+type Width = Int
+type Height = Int
+type Radius = Int
+
+
+-- | Draws an icon.
+icon :: FilePath -> DString
+icon = mkCmd True "i"
+
+
+-- | @rect w h@ draws and fills a rectangle of width @w@
+-- and height @h@. The rectangle is vertically centered
+-- (that is, if @h == 1@ then it is a centered line,
+-- something like @----@).
+rect :: Width -> Height -> DString
+rect = mkCmdX "r"
+
+-- | Like @rect@, but only draws and does not fills (i.e.
+-- draws an outline).
+rectO :: Width -> Height -> DString
+rectO = mkCmdX "ro"
+
+-- | Internal.
+mkCmdX :: String -> Width -> Height -> DString
+mkCmdX cmd w h = mkCmd True cmd (show w ++ 'x':show h)
+
+
+-- | @circ r@ draws and fils a circle of radius @r@, also
+-- vertically centered.
+circ :: Radius -> DString
+circ = mkCmd True "c" . show
+
+-- | Like @circ@, but does not fills.
+circO :: Radius -> DString
+circO = mkCmd True "co" . show
+
+
+-- | @pos p@ moves the position of the next input @p@ pixels
+-- to the right. Note that @p@ may be negative, effectively
+-- moving to the right.
+pos :: Int -> DString
+pos 0 = mempty
+pos n = mkCmd True "p" (show n)
+
+-- | @absPos p@ moves the position of the next input to be
+-- exactly @p@ pixels to the right of the initial position.
+-- This should be used with care.
+absPos :: Int -> DString
+absPos = mkCmd True "pa" . show
+
+
+-- | If @True@, the transformed @DString@ or @Printer@ will
+-- ignore the background colour (i.e. it will draw over what
+-- was already drawn). The default is @False@, the background
+-- colour is used.
+ignoreBg :: Transform a => Bool -> (a -> a)
+ignoreBg ignore = transformSt $ \st ->
+ if sIgnoreBg st == ignore then (st, id)
+ else (st {sIgnoreBg = ignore},
+ parens (ib ignore) (ib $ sIgnoreBg st))
+ where ib x = mkCmd False "ib" (if x then "1" else "0")
+
diff --git a/System/Dzen/Internal.hs b/System/Dzen/Internal.hs
new file mode 100644
--- /dev/null
+++ b/System/Dzen/Internal.hs
@@ -0,0 +1,183 @@
+-- |
+-- Module : System.Dzen.Internal
+-- Copyright : (c) 2009 Felipe A. Lessa
+-- License : GPL 3 (see the LICENSE file in the distribution)
+--
+-- Maintainer : felipe.lessa@gmail.com
+-- Stability : experimental
+-- Portability : semi-portable (MPTC and type families)
+--
+-- Internal data types and functions that are not exported
+-- to the outside world.
+
+module System.Dzen.Internal
+ (-- * State
+ DSt(..)
+ ,DColour
+
+ -- * DString
+ ,DString(..)
+ ,rawStr
+ ,toString
+ ,size
+ ,mkCmd
+
+ -- * Printer
+ ,Printer(..)
+ ,apply
+ ,Transform(..)
+ ) where
+
+
+import Control.Arrow
+import Control.Monad
+import Data.Colour
+import Data.String
+import Data.Monoid
+
+
+-- | The internal state we maintain. Currently it only contains
+-- the foreground and the background colours and if we are
+-- ignoring the background or not.
+--
+-- This state is passed around like a @Reader@ monad, each
+-- function receives it and does whatever it want, and not
+-- like a @State@ monad!
+data DSt = S {sFg :: !(Maybe DColour)
+ ,sBg :: !(Maybe DColour)
+ ,sIgnoreBg :: !Bool}
+
+-- | Our colours.
+type DColour = Colour Double
+
+-- | Empty state.
+emptyState :: DSt
+emptyState = S Nothing Nothing True
+
+
+
+
+
+-- | A @DString@ is used for constant string output, see 'str'.
+-- The @D@ on @DString@ stands for @dzen@, as these strings
+-- may change depending on the state (and that's why you
+-- shouldn't rely on 'Show', as it just uses an empty state)
+newtype DString = DS {unDS :: DSt -> (String -> String, Maybe Int)}
+-- A differencial list of chars (i.e. ShowS) and the number of chars.
+--
+-- Note that we use the @DStrings@ by themselves (i.e. concatenating
+-- with @Printers@) and for output of the @Printers@, but state is
+-- relevant only on the former. The @DString@s returned by Printers
+-- always get passed the @emptyState@. Of course it would be better to
+-- create two distinct data types, but we'll stick to this semantic
+-- hole for now.
+
+instance IsString DString where
+ fromString = DS . const . escape 0
+
+instance Show DString where
+ show (DS ds) = concat [""]
+
+instance Monoid DString where
+ mempty = DS $ const (id, Just 0)
+ mappend (DS ds1) (DS ds2) = DS $ \st -> ds1 st # ds2 st
+ -- Note how we duplicate 'st' above
+ where (s1,n1) # (s2,n2) = (s1 . s2, liftM2 (+) n1 n2)
+
+escape :: Int -> String -> (String -> String, Maybe Int)
+escape n s | n `seq` s `seq` False = error "escape: never here"
+escape n ('^':xs) = first (t.t) $ escape (n+1) xs where t = (.) ('^':)
+escape n ( x :xs) = first x' $ escape (n+1) xs where x' = (.) (x:)
+escape n [] = (id, Just n)
+
+
+-- | Converts a @String@ into a @DString@ without escaping anything.
+-- You /really/ don't need to use this, trust me!
+rawStr :: String -> DString
+rawStr str = DS $ const ((str ++), Just $ length str)
+
+-- | Converts a @DString@ back into a @String@. Note that
+-- @(toString . rawStr)@ is not @id@, otherwise @toString@
+-- would not work in some cases.
+-- Probably you don't need to use this, unless you want
+-- something like a static bar and nothing else.
+toString :: DString -> String
+toString = ("^ib(1)" ++) . ($ "") . fst . ($ emptyState) . unDS
+
+-- | Tries to get the number of characters of the @DString@.
+-- May return @Nothing@ when there are graphical objects.
+-- Probably you don't need to use this function.
+size :: DString -> Maybe Int
+size = snd . ($ emptyState) . unDS
+-- We apply a new empty state but that shouldn't be a problem
+-- because currently all functions that depend on the state
+-- do not change the size.
+
+-- | @mkCmd graph cmd arg@ creates a command string like
+-- @\"^cmd(arg)\"@. If @graph@ is @False@ then we give length zero
+-- to the resulting @DString@, otherwise we don't give a length
+-- (which propagates for strings concatenated to this). You should
+-- use @False@ whenever possible.
+mkCmd :: Bool -> String -> String -> DString
+mkCmd graph cmd arg = DS $ const (str, len)
+ where str = ('^':).(cmd++).('(':).(arg++).(')':)
+ len = if graph then Nothing else Just 0
+
+
+-- | A printer is used when the output depends on an input, so a
+-- @Printer a@ generates a 'DString' based on some input of
+-- type @a@ (and possibly updates some internal state).
+newtype Printer a = P {unP :: DSt -> a -> (DString, Printer a)}
+-- We don't use a Reader just because we already have
+-- to do a lot of pumbling ourselves anyway.
+
+-- | Apply a printer to an appropriate input, returning
+-- the output string and the new printer.
+apply :: Printer a -> a -> (String, Printer a)
+apply p i = first toString . ($ i) . ($ emptyState) . unP $ p
+-- We have apply here in Internal because it uses 'emptyState',
+-- which we don't want to export because its defaults are not
+-- the same as dzen's defaults (we use "ib(1)" by default).
+
+
+-- | @Transform@ is a specialization of @Functor@ for @DString@s.
+-- This class is used for functions that may receive @DString@
+-- or @Printer a@ as an argument because they operate only
+-- on their outputs and internal states (and not on the inputs).
+--
+-- So, whenever you see a function of type
+--
+-- > func :: Transform a => Blah -> Bleh -> a -> a
+--
+-- it means that @func@ can be used in two ways:
+--
+-- > func :: Blah -> Bleh -> DString -> DString
+-- > func :: Blah -> Bleh -> Printer a -> Printer a -- Printer of any input!
+--
+-- Try to have this in mind when reading the types.
+--
+-- Note: There is also a non-exported @transformSt@ for
+-- transforming the state in this class, otherwise it would
+-- be meaningless to use a class only for @transform@ (it
+-- would be better to make @liftT :: (DString -> DString)
+-- -> (Printer a -> Printer a)@).
+class Transform a where
+ -- | This function is 'id' on @DString@ and
+ -- modifies the output of a @Printer a@.
+ transform :: (DString -> DString) -> (a -> a)
+ transform f = transformSt (\st -> (st, f))
+
+ transformSt :: (DSt -> (DSt, DString -> DString)) -> (a -> a)
+
+instance Transform DString where
+ transform = id
+ transformSt f ds = DS $ \st -> let (st', dsT) = f st
+ in unDS (dsT ds) st'
+
+instance Transform (Printer a) where
+ transform f = P . (((f *** transform f) .) .) . unP
+ transformSt f (P p) = P $ \st i -> let (st', dsT) = f st
+ (ds, p') = p st' i
+ in (dsT ds, transformSt f p')
+
diff --git a/System/Dzen/Padding.hs b/System/Dzen/Padding.hs
new file mode 100644
--- /dev/null
+++ b/System/Dzen/Padding.hs
@@ -0,0 +1,169 @@
+-- |
+-- Module : System.Dzen.Padding
+-- Copyright : (c) 2009 Felipe A. Lessa
+-- License : GPL 3 (see the LICENSE file in the distribution)
+--
+-- Maintainer : felipe.lessa@gmail.com
+-- Stability : experimental
+-- Portability : semi-portable (uses MPTC and type families)
+--
+-- This is a handy module with functions for manual and automatic
+-- padding. To pad means to force the length of a string to be of a
+-- minimum size by adding /padding characters/ on either or both sides
+-- of the string (usually spaces). For example, padding the string
+-- @\"123\"@ to have length of 10 characters would give us the string
+--
+-- > " 123" -- if padding on the left
+-- > "123 " -- if padding on the right
+-- > " 123 " -- if padding on both sides
+--
+-- We provide two kinds of padding here:
+--
+-- [manual padding] This is the kind of padding you usually see
+-- in other (non-@dzen@) libraries. You give them the type of
+-- padding and the minimum length that you want and they will
+-- give you back another string. The @pad*@ functions do this
+-- with both plain @DString@s and with the output of @Printer@s.
+--
+-- [automatic padding] This is the same as a \"never shrink\"
+-- padding. An automatic padder adjusts its minimum length
+-- to be at least the greatest length it has seen so far, which
+-- means that an auto-padded @Printer@ will never shrink its
+-- size. This is very useful if you don't want everything swinging
+-- on your bar everytime the bar is updated.
+module System.Dzen.Padding
+ (-- * Manual padding
+ -- $padWarning
+ padL
+ ,padR
+ ,padC
+ ,pad
+ ,PadWhere(..)
+
+ -- * Automatic padding
+ -- $autoPad
+ ,autoPadL
+ ,autoPadR
+ ,autoPadC
+ ,autoPad
+ ) where
+
+import System.Dzen.Internal
+import System.Dzen.Base
+
+-- $padWarning
+--
+-- Note that there are commands that generate graphical
+-- outputs, such as 'System.Dzen.Graphics.rect', and we can't
+-- tell how many \"characters\" a graphic object has.
+-- Whenever you apply any of the padding functions below
+-- to a @DString@ that contains one of these graphical
+-- objects, there will be no padding. Note that colours
+-- do not affect padding as they do not have any width
+-- (and we don't mistake the command characters with
+-- the characters that will be shown).
+
+-- | Pads the given @DString@ or @Printer@ output
+-- with spaces to be at least @n@ chars in length
+padL :: Transform a => Int -> (a -> a)
+padL = pad ' ' PadLeft
+
+-- | Same as 'padL', but insert spaces on the right of the string.
+padR :: Transform a => Int -> (a -> a)
+padR = pad ' ' PadRight
+
+-- | Same as 'padL', but insert spaces on both sides,
+-- trying to keep the original contents in the middle.
+padC :: Transform a => Int -> (a -> a)
+padC = pad ' ' PadCenter
+
+-- | Generic pad function, padding with any character
+-- and in any place.
+pad :: Transform a => Char -> PadWhere -> Int -> (a -> a)
+pad c w n = transform $ DS . (pad' .) . unDS
+ where
+ pad' (string, Just k) | k < n =
+ (case w of
+ PadCenter -> repli (d+m) . string . repli d
+ PadLeft -> repli a . string
+ PadRight -> string . repli a, Just n)
+ where a = n-k; (d,m) = a `divMod` 2
+ repli = foldr (.) id . flip replicate (c:)
+ pad' other = other
+
+-- | Where to add the padding characters.
+data PadWhere = PadLeft | PadRight | PadCenter
+
+
+
+
+
+-- $autoPad
+--
+-- Automatic padding adjusts the number of padding characters
+-- dinamically, increasing the pad everytime the string
+-- size is greater than the pad size. For example, if
+-- you give @autoPadL 3@ the following strings
+--
+-- > "1"
+-- > "12"
+-- > "123"
+-- > "1234"
+-- > "12345"
+-- > "1234"
+-- > "12"
+-- > ""
+--
+-- then it will give the following outputs
+--
+-- > " 1"
+-- > " 12"
+-- > "123"
+-- > "1234"
+-- > "12345"
+-- > " 1234"
+-- > " 12"
+-- > " "
+--
+-- Using @autoPadC 3@ would give
+--
+-- > " 1 "
+-- > " 12"
+-- > "123"
+-- > "1234"
+-- > "12345"
+-- > " 1234"
+-- > " 12 "
+-- > " "
+--
+-- Some notes:
+--
+-- - If you're lazy you may give an initial number
+-- of zero and after some inputs the padding will be fine.
+--
+-- - If the automatic pad finds out that there is a graphical
+-- object at some string, then it will continue trying to
+-- pad the next strings. Although normally the strings will
+-- all contain graphics or not, we consider that the performance
+-- loss is negligible (and we do what the user expects).
+
+-- | Automatic padding for 'padL'.
+autoPadL :: Int -> (Printer a -> Printer a)
+autoPadL = autoPad ' ' PadLeft
+
+-- | Automatic padding for 'padR'.
+autoPadR :: Int -> (Printer a -> Printer a)
+autoPadR = autoPad ' ' PadRight
+
+-- | Automatic padding for 'padC'.
+autoPadC :: Int -> (Printer a -> Printer a)
+autoPadC = autoPad ' ' PadCenter
+
+-- | Generic automatic padding function, analog to 'pad'.
+autoPad :: Char -> PadWhere -> Int -> (Printer a -> Printer a)
+autoPad c w n pr =
+ P $ \st input -> let (output, pr') = unP pr st input
+ s = maybe 0 id $ size output
+ in case s `compare` n of
+ LT -> (pad c w n output, autoPad c w n pr')
+ _ -> (output, autoPad c w s pr')
diff --git a/System/Dzen/Process.hs b/System/Dzen/Process.hs
new file mode 100644
--- /dev/null
+++ b/System/Dzen/Process.hs
@@ -0,0 +1,115 @@
+-- |
+-- Module : System.Dzen.Process
+-- Copyright : (c) 2009 Felipe A. Lessa
+-- License : GPL 3 (see the LICENSE file in the distribution)
+--
+-- Maintainer : felipe.lessa@gmail.com
+-- Stability : experimental
+-- Portability : semi-portable (uses MPTC and type families)
+--
+-- Functions for creating supplies and running @dzen@.
+
+module System.Dzen.Process
+ (-- * Simple interface
+ runDzen
+ ,(##)
+
+ -- * Powerful interface
+ ,createDzen
+ ,createDzen'
+ ) where
+
+import Control.Concurrent
+import Control.Monad
+import Data.Function
+import System.IO
+import System.Process hiding (proc)
+import System.Dzen.Base
+
+
+-- | Pipes a 'Printer' to a fresh instance of @dzen@. It runs
+-- the following commands:
+--
+-- (1) Start @dzen@ with the supplied executable and arguments.
+--
+-- (2) Call the supply to get an input.
+--
+-- (3) Apply the input to the printer.
+--
+-- (4) Write the printer's output to @dzen@'s standard input.
+--
+-- (5) Sleeps for the specified delay using 'threadDelay'.
+--
+-- (6) Go back to step 2.
+--
+-- You may want to use this function inside a 'forkIO' if,
+-- for example, you're inside @xmonad@.
+runDzen :: FilePath -- ^ Path to @dzen@ executable, probably @\"dzen2\"@
+ -> [String] -- ^ Arguments for @dzen@.
+ -> Int -- ^ Delay between suplies in milliseconds. May be zero.
+ -> Printer a -- ^ @Printer@ to be used.
+ -> IO a -- ^ Supply of inputs.
+ -> IO ()
+runDzen path args delay printer get = do
+ handle <- createDzen' path args
+ let put s = hPutStrLn handle s >> threadDelay (delay * 1000)
+ applyForever printer get put
+
+
+
+-- | This is the same as @liftM2 (,)@, but with as a convenient
+-- operator with right infixity (the same as '+++'). For example,
+-- suppose you have printers
+--
+-- > prA :: Printer a
+-- > prB :: Printer b
+-- > prC :: Printer c
+--
+-- and supply functions
+--
+-- > getA :: m a
+-- > getB :: m b
+-- > getC :: m c
+--
+-- for some monad @m@. The final printer
+--
+-- > prFinal = prA +++ prB +++ prC
+--
+-- will be of type @Printer (a,(b,c))@, so you may use
+-- as its supply function
+--
+-- > getFinal = getA ## getB ## getC
+--
+-- which is of type @m (a,(b,c))@.
+(##) :: Monad m => m a -> m b -> m (a,b)
+(##) = liftM2 (,)
+
+infixr 4 ##
+
+-- | Runs a @dzen@ instance and returns its @stdin@ pipe.
+-- Both @stdout@ and @stderr@ of the new process will
+-- be the same as this process'. The pipe returned is
+-- already line buffered.
+--
+-- The first string is interpreted as a shell command
+-- to start @dzen@. Some examples of usage:
+--
+-- > createDzen (RawCommand "dzen2" ["-p"])
+-- > createDzen (ShellCommand "dzen2 -l 8 -bg #331100")
+createDzen :: CmdSpec -> IO Handle
+createDzen cmd = createProcess proc >>= extract
+ where proc = (shell "") {cmdspec = cmd
+ ,std_in = CreatePipe
+ ,std_out = Inherit
+ ,std_err = Inherit}
+ extract (Just handle, Nothing, Nothing, _) = do
+ hSetBuffering handle LineBuffering
+ return handle
+ extract _ = do
+ fail "createDzen: extract: (un)expected pipes"
+
+-- | Like @createDzen@, but never uses a shell (which is good).
+createDzen' :: FilePath -- ^ @dzen@ executable, likely @\"dzen2\"@
+ -> [String] -- ^ Arguments to @dzen@.
+ -> IO Handle
+createDzen' = (createDzen .) . RawCommand
diff --git a/dzen-utils.cabal b/dzen-utils.cabal
new file mode 100644
--- /dev/null
+++ b/dzen-utils.cabal
@@ -0,0 +1,40 @@
+cabal-version: >= 1.2.3
+name: dzen-utils
+version: 0.1
+synopsis: Utilities for creating inputs for dzen.
+category: System
+license: GPL
+license-file: LICENSE
+author: Felipe Almeida Lessa
+copyright: (c) 2009 Felipe A. Lessa
+maintainer: felipe.lessa@gmail.com
+build-type: Simple
+tested-with: GHC
+extra-source-files: Example1.hs, Example2.hs
+description:
+ This library has everything you need to create your @dzen@'s
+ bar input strings using powerful combinators in a type-safe way.
+ .
+ It can be used to create standalone \"scripts\" with @runhaskell@
+ or it can be used inside @xmonad@'s main function.
+ .
+ To see what can be done, please read the documentation of the
+ toplevel module "System.Dzen".
+
+library
+ build-depends: base >= 4, colour >= 2.2, process >= 1.0
+ ghc-options: -Wall
+ extensions:
+ MultiParamTypeClasses,
+ OverloadedStrings,
+ TypeFamilies
+ exposed-modules:
+ System.Dzen,
+ System.Dzen.Base,
+ System.Dzen.Colour,
+ System.Dzen.Graphics,
+ System.Dzen.Padding,
+ System.Dzen.Bars,
+ System.Dzen.Process
+ other-modules:
+ System.Dzen.Internal