{- This module was generated from data in the Kate syntax highlighting file eiffel.xml, version 1.02,
   by  Sebastian Vuorinen -}

module Text.Highlighting.Kate.Syntax.Eiffel ( highlight, parseExpression, syntaxName, syntaxExtensions ) where
import Text.Highlighting.Kate.Definitions
import Text.Highlighting.Kate.Common
import Text.ParserCombinators.Parsec
import Data.List (nub)
import qualified Data.Set as Set
import Data.Map (fromList)
import Data.Maybe (fromMaybe)

-- | Full name of language.
syntaxName :: String
syntaxName = "Eiffel"

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

-- | 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 = "Eiffel" }
  context <- currentContext <|> (pushContext "Normal" >> 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 [("Eiffel",["Normal"])], synStLanguage = "Eiffel", synStCurrentLine = "", synStCharsParsedInLine = 0, synStPrevChar = '\n', synStCaseSensitive = True, synStKeywordCaseSensitive = True, synStCaptures = []}

parseSourceLine = manyTill parseExpressionInternal pEndLine

pEndLine = do
  newline <|> (eof >> return '\n')
  context <- currentContext
  case context of
    "Normal" -> return ()
    "Quoted String" -> (popContext >> return ())
    "Documentation" -> (popContext >> return ())
    _ -> return ()
  lineContents <- lookAhead wholeLine
  updateState $ \st -> st { synStCurrentLine = lineContents, synStCharsParsedInLine = 0, synStPrevChar = '\n' }

withAttribute attr txt = do
  if null txt
     then fail "Parser matched no text"
     else return ()
  let style = fromMaybe "" $ lookup attr styles
  st <- getState
  let oldCharsParsed = synStCharsParsedInLine st
  let prevchar = if null txt then '\n' else last txt
  updateState $ \st -> st { synStCharsParsedInLine = oldCharsParsed + length txt, synStPrevChar = prevchar } 
  return (nub [style, attr], txt)

styles = [("Normal Text","Normal"),("Keyword","Keyword"),("Predefined entities","Others"),("Assertions","Others"),("Decimal","DecVal"),("Float","Float"),("Char","Char"),("String","String"),("Comment","Comment")]

parseExpressionInternal = do
  context <- currentContext
  parseRules context <|> (pDefault >>= withAttribute (fromMaybe "" $ lookup context defaultAttributes))

list_keywords = Set.fromList $ words $ "agent alias all and as assign class convert create creation debug deferred do else elseif end expanded export external feature from frozen if implies indexing infix inherit inspect is like local loop not obsolete old once or prefix pure redefine reference rename rescue retry separate then undefine"
list_predefined'2dentities = Set.fromList $ words $ "Current False Precursor Result True TUPLE"
list_assertions = Set.fromList $ words $ "check ensure require variant invariant"


defaultAttributes = [("Normal","Normal Text"),("Quoted String","String"),("Documentation","Comment")]

parseRules "Normal" = 
  do (attr, result) <- (((pKeyword " \n\t.():!+,-<=>%&*/;?[]^{|}~\\" list_keywords >>= withAttribute "Keyword"))
                        <|>
                        ((pKeyword " \n\t.():!+,-<=>%&*/;?[]^{|}~\\" list_predefined'2dentities >>= withAttribute "Predefined entities"))
                        <|>
                        ((pKeyword " \n\t.():!+,-<=>%&*/;?[]^{|}~\\" list_assertions >>= withAttribute "Assertions"))
                        <|>
                        ((pInt >>= withAttribute "Decimal"))
                        <|>
                        ((pFloat >>= withAttribute "Float"))
                        <|>
                        ((pHlCChar >>= withAttribute "Char"))
                        <|>
                        ((pDetectChar False '"' >>= withAttribute "String") >>~ pushContext "Quoted String")
                        <|>
                        ((pDetect2Chars False '-' '-' >>= withAttribute "Comment") >>~ pushContext "Documentation"))
     return (attr, result)

parseRules "Quoted String" = 
  do (attr, result) <- ((pDetectChar False '"' >>= withAttribute "String") >>~ (popContext >> return ()))
     return (attr, result)

parseRules "Documentation" = 
  pzero

parseRules x = fail $ "Unknown context" ++ x