{- This module was generated from data in the Kate syntax highlighting file noweb.xml, version 1.0,
   by  Scott Collins (scc@scottcollins.net) -}

module Text.Highlighting.Kate.Syntax.Noweb ( highlight, parseExpression, syntaxName, syntaxExtensions ) where
import Text.Highlighting.Kate.Definitions
import Text.Highlighting.Kate.Common
import qualified Text.Highlighting.Kate.Syntax.Html
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 = "noweb"

-- | Filename extensions for this language.
syntaxExtensions :: String
syntaxExtensions = "*.w;*.nw"

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

parseSourceLine = manyTill parseExpressionInternal pEndLine

pEndLine = do
  lookAhead $ newline <|> (eof >> return '\n')
  context <- currentContext
  case context of
    "RawDocumentation" -> return () >> pHandleEndLine
    "CodeQuote" -> return () >> pHandleEndLine
    "CodeSection" -> return () >> pHandleEndLine
    "SectionNames" -> 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 = [("Punctuation","re"),("SectionName","re")]

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


regex_'3c'3c'2e'2a'3e'3e'3d'24 = compileRegex "<<.*>>=$"
regex_'5c'5d'5c'5d'28'3f'21'5c'5d'29 = compileRegex "\\]\\](?!\\])"
regex_'40'24 = compileRegex "@$"
regex_'40'28'3f'3d'5b'5cs'25'5d'29 = compileRegex "@(?=[\\s%])"
regex_'40'3c'3c = compileRegex "@<<"
regex_'3c'3c'2e'2a'5b'5e'40'5d'3e'3e'28'3f'21'3d'29 = compileRegex "<<.*[^@]>>(?!=)"

defaultAttributes = [("RawDocumentation","Prose"),("CodeQuote","Code"),("CodeSection","Code"),("SectionNames","Prose")]

parseRules "RawDocumentation" = 
  do (attr, result) <- (((pColumn 0 >> pRegExpr regex_'3c'3c'2e'2a'3e'3e'3d'24 >>= withAttribute "SectionName") >>~ pushContext "CodeSection")
                        <|>
                        ((pDetect2Chars False '@' '[' >>= withAttribute "Prose"))
                        <|>
                        ((pDetect2Chars False '[' '[' >>= withAttribute "Punctuation") >>~ pushContext "CodeQuote")
                        <|>
                        ((Text.Highlighting.Kate.Syntax.Html.parseExpression)))
     return (attr, result)

parseRules "CodeQuote" = 
  do (attr, result) <- (((pDetect2Chars False '@' ']' >>= withAttribute "Code"))
                        <|>
                        ((pRegExpr regex_'5c'5d'5c'5d'28'3f'21'5c'5d'29 >>= withAttribute "Punctuation") >>~ (popContext))
                        <|>
                        ((parseRules "SectionNames"))
                        <|>
                        ((Text.Highlighting.Kate.Syntax.Cpp.parseExpression)))
     return (attr, result)

parseRules "CodeSection" = 
  do (attr, result) <- (((pColumn 0 >> pRegExpr regex_'40'24 >>= withAttribute "Punctuation") >>~ pushContext "RawDocumentation")
                        <|>
                        ((pColumn 0 >> pRegExpr regex_'40'28'3f'3d'5b'5cs'25'5d'29 >>= withAttribute "Punctuation") >>~ pushContext "RawDocumentation")
                        <|>
                        ((pColumn 0 >> lookAhead (pRegExpr regex_'3c'3c'2e'2a'3e'3e'3d'24) >> return ([],"") ) >>~ pushContext "RawDocumentation")
                        <|>
                        ((parseRules "SectionNames"))
                        <|>
                        ((Text.Highlighting.Kate.Syntax.Cpp.parseExpression)))
     return (attr, result)

parseRules "SectionNames" = 
  do (attr, result) <- (((pRegExpr regex_'40'3c'3c >>= withAttribute "Prose"))
                        <|>
                        ((pRegExpr regex_'3c'3c'2e'2a'5b'5e'40'5d'3e'3e'28'3f'21'3d'29 >>= withAttribute "SectionName")))
     return (attr, result)

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