-- | This is a library which colourises Haskell code.
-- It currently has six output formats:
--
-- * ANSI terminal codes
--
-- * LaTeX macros
--
-- * HTML 3.2 with font tags
--
-- * HTML 4.01 with external CSS.
--
-- * XHTML 1.0 with internal CSS.
--
-- * mIRC chat client colour codes.
--
module Language.Haskell.HsColour (Output(..), ColourPrefs(..),
hscolour) where
import Language.Haskell.HsColour.Colourise (ColourPrefs(..))
import qualified Language.Haskell.HsColour.TTY as TTY
import qualified Language.Haskell.HsColour.HTML as HTML
import qualified Language.Haskell.HsColour.CSS as CSS
import qualified Language.Haskell.HsColour.InlineCSS as ICSS
import qualified Language.Haskell.HsColour.LaTeX as LaTeX
import qualified Language.Haskell.HsColour.MIRC as MIRC
import Data.List(mapAccumL, isPrefixOf)
import Data.Maybe
import Language.Haskell.HsColour.Output
import Debug.Trace
-- | Colourise Haskell source code with the given output format.
hscolour :: Output -- ^ Output format.
-> ColourPrefs -- ^ Colour preferences (for formats that support them).
-> Bool -- ^ Whether to include anchors.
-> Bool -- ^ Whether output document is partial or complete.
-> String -- ^ Title for output.
-> Bool -- ^ Whether input document is literate haskell or not
-> String -- ^ Haskell source code.
-> String -- ^ Coloured Haskell source code.
hscolour output pref anchor partial title False =
(if partial then id else top'n'tail output title) .
hscolour' output pref anchor
hscolour output pref anchor partial title True =
(if partial then id else top'n'tail output title) .
concatMap chunk . joinL . classify . inlines
where
chunk (Code c) = hscolour' output pref anchor c
chunk (Lit c) = c
-- | The actual colourising worker, despatched on the chosen output format.
hscolour' :: Output -- ^ Output format.
-> ColourPrefs -- ^ Colour preferences (for formats that support them)
-> Bool -- ^ Whether to include anchors.
-> String -- ^ Haskell source code.
-> String -- ^ Coloured Haskell source code.
hscolour' TTY pref _ = TTY.hscolour pref
hscolour' MIRC pref _ = MIRC.hscolour pref
hscolour' LaTeX pref _ = LaTeX.hscolour pref
hscolour' HTML pref anchor = HTML.hscolour pref anchor
hscolour' CSS _ anchor = CSS.hscolour anchor
hscolour' ICSS pref anchor = ICSS.hscolour pref anchor
-- | Choose the right headers\/footers, depending on the output format.
top'n'tail :: Output -- ^ Output format
-> String -- ^ Title for output
-> (String->String) -- ^ Output transformer
top'n'tail TTY _ = id
top'n'tail MIRC _ = id
top'n'tail LaTeX title = LaTeX.top'n'tail title
top'n'tail HTML title = HTML.top'n'tail title
top'n'tail CSS title = CSS.top'n'tail title
top'n'tail ICSS title = ICSS.top'n'tail title
-- | Separating literate files into code\/comment chunks.
data Lit = Code {unL :: String} | Lit {unL :: String} deriving (Show)
-- Re-implementation of 'lines', for better efficiency (but decreased laziness).
-- Also, importantly, accepts non-standard DOS and Mac line ending characters.
-- And retains the trailing '\n' character in each resultant string.
inlines :: String -> [String]
inlines s = lines' s id
where
lines' [] acc = [acc []]
lines' ('\^M':'\n':s) acc = acc ['\n'] : lines' s id -- DOS
--lines' ('\^M':s) acc = acc ['\n'] : lines' s id -- MacOS
lines' ('\n':s) acc = acc ['\n'] : lines' s id -- Unix
lines' (c:s) acc = lines' s (acc . (c:))
-- | The code for classify is largely stolen from Language.Preprocessor.Unlit.
classify [] = []
classify (x:xs) | "\\begin{code}"`isPrefixOf`x
= Lit x: allProg xs
where allProg [] = [] -- Should give an error message,
-- but I have no good position information.
allProg (x:xs) | "\\end{code}"`isPrefixOf`x
= Lit x: classify xs
allProg (x:xs) = Code x: allProg xs
classify (('>':x):xs) = Code ('>':x) : classify xs
classify (x:xs) = Lit x: classify xs
-- | Join up chunks of code\/comment that are next to each other.
joinL :: [Lit] -> [Lit]
joinL [] = []
joinL (Code c:Code c2:xs) = joinL (Code (c++c2):xs)
joinL (Lit c :Lit c2 :xs) = joinL (Lit (c++c2):xs)
joinL (any:xs) = any: joinL xs