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

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

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

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

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

parseSourceLine = manyTill parseExpressionInternal pEndLine

pEndLine = do
  lookAhead $ newline <|> (eof >> return '\n')
  context <- currentContext
  case context of
    "Normal Text" -> return () >> pHandleEndLine
    "Attribute" -> return () >> pHandleEndLine
    "Value" -> return () >> pHandleEndLine
    "Value 2" -> return () >> pHandleEndLine
    "Comment" -> return () >> pHandleEndLine
    _ -> pHandleEndLine

withAttribute attr txt = do
  when (null txt) $ fail "Parser matched no text"
  let labs = attr : maybeToList (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 (labs, txt)

styles = [("Tag","kw"),("Attribute Name","ot"),("Attribute Value","dt"),("Comment","co")]

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


regex_'3c'5cs'2a'5c'2f'3f'5cs'2a'5ba'2dzA'2dZ'5f'3a'5d'5ba'2dzA'2dZ0'2d9'2e'5f'3a'2d'5d'2a = compileRegex "<\\s*\\/?\\s*[a-zA-Z_:][a-zA-Z0-9._:-]*"
regex_'5cs'2a'3d'5cs'2a = compileRegex "\\s*=\\s*"

defaultAttributes = [("Normal Text","Normal Text"),("Attribute","Attribute Name"),("Value","Attribute Value"),("Value 2","Attribute Value"),("Comment","Comment")]

parseRules "Normal Text" = 
  do (attr, result) <- (((pString False "<!--" >>= withAttribute "Comment") >>~ pushContext "Comment")
                        <|>
                        ((pRegExpr regex_'3c'5cs'2a'5c'2f'3f'5cs'2a'5ba'2dzA'2dZ'5f'3a'5d'5ba'2dzA'2dZ0'2d9'2e'5f'3a'2d'5d'2a >>= withAttribute "Tag") >>~ pushContext "Attribute"))
     return (attr, result)

parseRules "Attribute" = 
  do (attr, result) <- (((pDetect2Chars False '/' '>' >>= withAttribute "Tag") >>~ (popContext))
                        <|>
                        ((pDetectChar False '>' >>= withAttribute "Tag") >>~ (popContext))
                        <|>
                        ((pRegExpr regex_'5cs'2a'3d'5cs'2a >>= withAttribute "Normal Text") >>~ pushContext "Value"))
     return (attr, result)

parseRules "Value" = 
  do (attr, result) <- (((pDetect2Chars False '/' '>' >>= withAttribute "Tag") >>~ (popContext >> popContext))
                        <|>
                        ((pDetectChar False '>' >>= withAttribute "Tag") >>~ (popContext >> popContext))
                        <|>
                        ((pDetectChar False '"' >>= withAttribute "Attribute Value") >>~ pushContext "Value 2"))
     return (attr, result)

parseRules "Value 2" = 
  do (attr, result) <- ((pDetectChar False '"' >>= withAttribute "Attribute Value") >>~ (popContext >> popContext))
     return (attr, result)

parseRules "Comment" = 
  do (attr, result) <- ((pString False "-->" >>= withAttribute "Comment") >>~ (popContext))
     return (attr, result)

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