module Language.Haskell.Stylish.Config
( Extensions
, Config (..)
, defaultConfigFilePath
, configFilePath
, loadConfig
) where
import Control.Applicative (pure, (<$>), (<*>))
import Control.Monad (forM, msum, mzero)
import Data.Aeson (FromJSON (..))
import qualified Data.Aeson as A
import qualified Data.Aeson.Types as A
import qualified Data.ByteString as B
import Data.List (intercalate)
import Data.Map (Map)
import qualified Data.Map as M
import Data.Yaml (decodeEither)
import System.Directory
import System.FilePath ((</>))
import Paths_stylish_haskell (getDataFileName)
import Language.Haskell.Stylish.Step
import qualified Language.Haskell.Stylish.Step.Imports as Imports
import qualified Language.Haskell.Stylish.Step.LanguagePragmas as LanguagePragmas
import qualified Language.Haskell.Stylish.Step.Records as Records
import qualified Language.Haskell.Stylish.Step.Tabs as Tabs
import qualified Language.Haskell.Stylish.Step.TrailingWhitespace as TrailingWhitespace
import qualified Language.Haskell.Stylish.Step.UnicodeSyntax as UnicodeSyntax
import Language.Haskell.Stylish.Verbose
type Extensions = [String]
data Config = Config
{ configSteps :: [Step]
, configColumns :: Int
, configLanguageExtensions :: [String]
}
instance FromJSON Config where
parseJSON = parseConfig
emptyConfig :: Config
emptyConfig = Config [] 80 []
configFileName :: String
configFileName = ".stylish-haskell.yaml"
defaultConfigFilePath :: IO FilePath
defaultConfigFilePath = getDataFileName "data/stylish-haskell.yaml"
configFilePath :: Verbose -> Maybe FilePath -> IO (Maybe FilePath)
configFilePath verbose userSpecified = do
(current, currentE) <- check $ (</> configFileName) <$> getCurrentDirectory
(home, homeE) <- check $ (</> configFileName) <$> getHomeDirectory
(def, defE) <- check defaultConfigFilePath
return $ msum
[ userSpecified
, if currentE then Just current else Nothing
, if homeE then Just home else Nothing
, if defE then Just def else Nothing
]
where
check fp = do
fp' <- fp
ex <- doesFileExist fp'
verbose $ fp' ++ if ex then " exists" else " does not exist"
return (fp', ex)
loadConfig :: Verbose -> Maybe FilePath -> IO Config
loadConfig verbose mfp = do
mfp' <- configFilePath verbose mfp
case mfp' of
Nothing -> do
verbose $ "Using empty configuration"
return emptyConfig
Just fp -> do
verbose $ "Loading configuration at " ++ fp
bs <- B.readFile fp
case decodeEither bs of
Left err -> error $
"Language.Haskell.Stylish.Config.loadConfig: " ++ err
Right config -> return config
parseConfig :: A.Value -> A.Parser Config
parseConfig (A.Object o) = do
config <- Config
<$> pure []
<*> (o A..:? "columns" A..!= 80)
<*> (o A..:? "language_extensions" A..!= [])
steps <- (o A..: "steps" >>= fmap concat . mapM (parseSteps config))
return config {configSteps = steps}
parseConfig _ = mzero
catalog :: Map String (Config -> A.Object -> A.Parser Step)
catalog = M.fromList
[ ("imports", parseImports)
, ("language_pragmas", parseLanguagePragmas)
, ("records", parseRecords)
, ("tabs", parseTabs)
, ("trailing_whitespace", parseTrailingWhitespace)
, ("unicode_syntax", parseUnicodeSyntax)
]
parseSteps :: Config -> A.Value -> A.Parser [Step]
parseSteps config val = do
map' <- parseJSON val :: A.Parser (Map String A.Value)
forM (M.toList map') $ \(k, v) -> case (M.lookup k catalog, v) of
(Just parser, A.Object o) -> parser config o
_ -> fail $ "Invalid declaration for " ++ k
parseEnum :: [(String, a)] -> a -> Maybe String -> A.Parser a
parseEnum _ def Nothing = return def
parseEnum strs _ (Just k) = case lookup k strs of
Just v -> return v
Nothing -> fail $ "Unknown option: " ++ k ++ ", should be one of: " ++
intercalate ", " (map fst strs)
parseImports :: Config -> A.Object -> A.Parser Step
parseImports config o = Imports.step
<$> pure (configColumns config)
<*> (o A..:? "align" >>= parseEnum aligns Imports.Global)
where
aligns =
[ ("global", Imports.Global)
, ("file", Imports.File)
, ("group", Imports.Group)
, ("none", Imports.None)
]
parseLanguagePragmas :: Config -> A.Object -> A.Parser Step
parseLanguagePragmas config o = LanguagePragmas.step
<$> pure (configColumns config)
<*> (o A..:? "style" >>= parseEnum styles LanguagePragmas.Vertical)
<*> o A..:? "remove_redundant" A..!= True
where
styles =
[ ("vertical", LanguagePragmas.Vertical)
, ("compact", LanguagePragmas.Compact)
]
parseRecords :: Config -> A.Object -> A.Parser Step
parseRecords _ _ = return Records.step
parseTabs :: Config -> A.Object -> A.Parser Step
parseTabs _ o = Tabs.step
<$> o A..:? "spaces" A..!= 8
parseTrailingWhitespace :: Config -> A.Object -> A.Parser Step
parseTrailingWhitespace _ _ = return TrailingWhitespace.step
parseUnicodeSyntax :: Config -> A.Object -> A.Parser Step
parseUnicodeSyntax _ o = UnicodeSyntax.step
<$> o A..:? "add_language_pragma" A..!= True