{- This module was generated from data in the Kate syntax highlighting file yacc.xml, version 1.03,
   by  Jan Villat (jan.villat@net2000.ch) -}

module Text.Highlighting.Kate.Syntax.Yacc ( highlight, parseExpression, syntaxName, syntaxExtensions ) where
import Text.Highlighting.Kate.Definitions
import Text.Highlighting.Kate.Common
import qualified Text.Highlighting.Kate.Syntax.Cpp
import Text.ParserCombinators.Parsec
import Control.Monad (when)
import Data.Map (fromList)
import Data.Maybe (fromMaybe, maybeToList)

-- | Full name of language.
syntaxName :: String
syntaxName = "Yacc/Bison"

-- | Filename extensions for this language.
syntaxExtensions :: String
syntaxExtensions = "*.y"

-- | Highlight source code using this syntax definition.
highlight :: String -> Either String [SourceLine]
highlight input =
  case runParser parseSource startingState "source" input of
    Left err     -> Left $ show err
    Right result -> Right result

-- | Parse an expression using appropriate local context.
parseExpression :: GenParser Char SyntaxState LabeledSource
parseExpression = do
  st <- getState
  let oldLang = synStLanguage st
  setState $ st { synStLanguage = "Yacc/Bison" }
  context <- currentContext <|> (pushContext "Pre Start" >> currentContext)
  result <- parseRules context
  updateState $ \st -> st { synStLanguage = oldLang }
  return result

parseSource = do 
  lineContents <- lookAhead wholeLine
  updateState $ \st -> st { synStCurrentLine = lineContents }
  result <- manyTill parseSourceLine eof
  return $ map normalizeHighlighting result

startingState = SyntaxState {synStContexts = fromList [("Yacc/Bison",["Pre Start"e="parseExpression">