module Html.SyntaxColoring
  ( Program, Code (..), TypeKind (..), ConstructorKind (..)
  , IdentifierKind (..), FunctionKind (..)
  , genProgram, code2string, getQualIdent, position2code, area2codes
  ) where

import Data.Char hiding (Space)
import Data.Function (on)
import Data.Maybe (fromMaybe, mapMaybe)
import Data.List (intersperse, nubBy, partition)
import Debug.Trace (trace)

import Curry.Base.Ident
import Curry.Base.Position
import Curry.Base.MessageMonad
import Curry.Syntax hiding (infixOp)
import Curry.Syntax.Lexer

debug :: Bool
debug = False -- mergen von Token und Codes

trace' :: String -> a -> a
trace' s x = if debug then trace s x else x

debug' :: Bool
debug' = False -- messages

trace'' :: String -> a -> a
trace'' s x = if debug' then trace s x else x

type Program = [(Int, Int, Code)]

data Code =  Keyword String
           | Space Int
           | NewLine
           | ConstructorName ConstructorKind QualIdent
           | TypeConstructor TypeKind QualIdent
           | Function FunctionKind QualIdent
           | ModuleName ModuleIdent
           | Commentary String
           | NumberCode String
           | StringCode String
           | CharCode String
           | Symbol String
           | Identifier IdentifierKind QualIdent
           | CodeWarning [Message] Code
           | NotParsed String
             deriving Show

data TypeKind = TypeDecla
              | TypeUse
              | TypeExport deriving Show

data ConstructorKind = ConstrPattern
                     | ConstrCall
                     | ConstrDecla
                     | OtherConstrKind deriving Show

data IdentifierKind = IdDecl
                    | IdOccur
                    | UnknownId  deriving Show

data FunctionKind = InfixFunction
                  | TypSig
                  | FunDecl
                  | FunctionCall
                  | OtherFunctionKind deriving Show

--- @param plaintext
--- @param list with parse-Results with descending quality  e.g. [typingParse, fullParse, parse]
--- @param lex-Result
--- @return program
genProgram :: String -> [MsgMonad Module] -> MsgMonad [(Position, Token)] -> Program
genProgram plainText parseResults m = case runMsg m of
  (Left e, msgs) -> buildMessagesIntoPlainText (e : msgs) plainText
  (Right posNtokList, mess) ->
    let messages = (prepareMessages (concatMap getMessages parseResults ++ mess))
        mergedMessages = (mergeMessages' (trace' ("Messages: " ++ show messages) messages) posNtokList)
        (nameList,codes) = catIdentifiers parseResults
    in tokenNcodes2codes nameList 1 1 mergedMessages codes

--- @param Program
--- @param line
--- @param col
--- @return Code at this Position
position2code :: Program -> Int -> Int -> Maybe Code
position2code []  _ _ = Nothing
position2code [_] _ _ = Nothing
position2code ((l,c,code):xs@((_,c2,_):_)) lin col
     | lin == l && col >= c && col < c2 = Just code
     | l > lin = Nothing
     | otherwise = position2code xs lin col

area2codes :: Program -> Position -> Position -> [Code]
area2codes [] _ _ = []
area2codes xxs@((l,c,code):xs) p1@Position{file=f} p2
     | p1 > p2 = area2codes xxs p2 p1
     | posEnd >= p1 && posBegin <= p2  = code : area2codes xs p1 p2
     | posBegin > p2 = []
     | otherwise = area2codes xs p1 p2
   where
      posBegin = Position f l c noRef
      posEnd   = Position f l (c + length (code2string code)) noRef
area2codes _ _ _ = error "SyntaxColoring.area2codes: no pattern match"

--- @param code
--- @return qualIdent if available
getQualIdent :: Code -> Maybe QualIdent
getQualIdent (ConstructorName _ qualIdent) = Just qualIdent
getQualIdent (Function _ qualIdent) = Just qualIdent
getQualIdent (Identifier _ qualIdent) = Just qualIdent
getQualIdent (TypeConstructor _ qualIdent) = Just qualIdent
getQualIdent  _ = Nothing

-- DEBUGGING----------- wird bald nicht mehr gebraucht

setMessagePosition :: Message -> Message
setMessagePosition m@(Message (Just p) _) = trace'' ("pos:" ++ show p ++ ":" ++ show m) m
setMessagePosition (Message _ m) =
        let mes@(Message pos _) =  (Message (getPositionFromString m) m) in
        trace'' ("pos:" ++ show pos ++ ":" ++ show mes) mes

getPositionFromString :: String -> Maybe Position
getPositionFromString message =
     if l > 0 && c > 0
          then Just Position{file=f,line=l,column=c,astRef=noRef}
          else Nothing
  where
      f = takeWhile (/= '"') (tail (dropWhile (/= '"') message))
      l = readInt (takeWhile (/= '.') (drop 7 (dropWhile (/= ',') message)))
      c = readInt (takeWhile (/= ':') (tail (dropWhile (/= '.') (drop 7 (dropWhile (/= ',') message)))))


readInt :: String -> Int
readInt s =
      let onlyNum = filter isDigit s in
      if null onlyNum
         then 0
         else read onlyNum :: Int

flatCode :: Code -> Code
flatCode (CodeWarning _ code) = code
flatCode code = code

-- ----------Message---------------------------------------

getMessages :: MsgMonad a -> [Message]
getMessages = snd . runMsg --(Result mess _) = mess
-- getMessages (Failure mess) = mess

lessMessage :: Message -> Message -> Bool
lessMessage (Message mPos1 _) (Message mPos2 _) = mPos1 < mPos2

nubMessages :: [Message] -> [Message]
nubMessages = nubBy eqMessage

eqMessage :: Message -> Message -> Bool
eqMessage (Message p1 s1) (Message p2 s2) = (p1 == p2) && (s1 == s2)

prepareMessages :: [Message] -> [Message]
prepareMessages = qsort lessMessage . map setMessagePosition . nubMessages


buildMessagesIntoPlainText :: [Message] -> String -> Program
buildMessagesIntoPlainText messages text =
    buildMessagesIntoPlainText' messages (lines text) [] 1
 where
    buildMessagesIntoPlainText' :: [Message] -> [String] -> [String] -> Int -> Program
    buildMessagesIntoPlainText' _ [] [] _ =
          []
    buildMessagesIntoPlainText' _ [] postStrs ln =
          [(ln,1,NotParsed (unlines postStrs))]
    buildMessagesIntoPlainText' [] preStrs postStrs ln =
          [(ln,1,NotParsed (unlines (preStrs ++ postStrs)))]

    buildMessagesIntoPlainText' messages1 (str:preStrs) postStrs ln =
          let (pre,post) = partition isLeq messages1 in
          if null pre
             then buildMessagesIntoPlainText' post preStrs (postStrs ++ [str]) (ln + 1)
             else (ln,1,NotParsed (unlines postStrs)) :
                  (ln,1,CodeWarning pre (NotParsed str)) :
                  (ln,1,NewLine) :
                  buildMessagesIntoPlainText' post preStrs [] (ln + 1)
      where
         isLeq (Message (Just p) _) = line p <= ln
         isLeq _ = True

--- @param parse-Modules  [typingParse,fullParse,parse]
catIdentifiers :: [MsgMonad Module] -> ([(ModuleIdent,ModuleIdent)],[Code])
catIdentifiers = catIds . rights_sc . map (fst . runMsg)
    where
      catIds [] = ([],[])
      catIds [m] =
          catIdentifiers' m Nothing
      catIds rs@(m:_:_) =
          catIdentifiers' (last rs) (Just m)

-- not in base befoer base4
rights_sc :: [Either a b] -> [b]
rights_sc  xs = [ x | Right x <- xs]

--- @param parse-Module
--- @param Maybe betterParse-Module
catIdentifiers' :: Module -> Maybe Module -> ([(ModuleIdent,ModuleIdent)],[Code])
catIdentifiers' (Module moduleIdent maybeExportSpec decls)
                Nothing =
      let codes = (concatMap decl2codes (qsort lessDecl decls)) in
      (concatMap renamedImports decls,
      ModuleName moduleIdent :
       maybe [] exportSpec2codes maybeExportSpec ++ codes)
catIdentifiers' (Module moduleIdent maybeExportSpec1 _)
                (Just (Module _ maybeExportSpec2 decls)) =
      let codes = (concatMap decl2codes (qsort lessDecl decls)) in
      (concatMap renamedImports decls,
      replaceFunctionCalls $
        map (addModuleIdent moduleIdent)
          ([ModuleName moduleIdent] ++
           mergeExports2codes
              (maybe [] (\(Exporting _ i) -> i)  maybeExportSpec1)
              (maybe [] (\(Exporting _ i) -> i)  maybeExportSpec2) ++
           codes))


renamedImports :: Decl -> [(ModuleIdent,ModuleIdent)]
renamedImports decl =
    case decl of
        (ImportDecl _ oldName _ (Just newName) _) -> [(oldName,newName)]
        _ -> []


replaceFunctionCalls :: [Code] -> [Code]
replaceFunctionCalls codes = map (idOccur2functionCall qualIdents) codes
   where
      qualIdents = findFunctionDecls codes


findFunctionDecls :: [Code] -> [QualIdent]
findFunctionDecls  =  mapMaybe getQualIdent .
                      filter isFunctionDecl .
                      map flatCode

isFunctionDecl  :: Code -> Bool
isFunctionDecl  (Function FunDecl _)  = True
isFunctionDecl  _ = False

idOccur2functionCall :: [QualIdent] -> Code -> Code
idOccur2functionCall qualIdents ide@(Identifier IdOccur qualIdent)
   | isQualified qualIdent = Function FunctionCall qualIdent
   | elem qualIdent qualIdents = Function FunctionCall qualIdent
   | otherwise = ide
idOccur2functionCall qualIdents (CodeWarning mess code) =
       CodeWarning mess (idOccur2functionCall qualIdents code)
idOccur2functionCall _ code = code


addModuleIdent :: ModuleIdent -> Code -> Code
addModuleIdent moduleIdent c@(Function x qualIdent)
    | uniqueId (unqualify qualIdent) == 0 =
        Function x (qualQualify moduleIdent qualIdent)
    | otherwise = c
addModuleIdent moduleIdent cn@(ConstructorName x qualIdent)
    | not $ isQualified qualIdent =
        ConstructorName x (qualQualify moduleIdent qualIdent)
    | otherwise = cn
addModuleIdent moduleIdent tc@(TypeConstructor TypeDecla qualIdent)
    | not $ isQualified qualIdent =
        TypeConstructor TypeDecla (qualQualify moduleIdent qualIdent)
    | otherwise = tc
addModuleIdent moduleIdent (CodeWarning mess code) =
    CodeWarning mess (addModuleIdent moduleIdent code)
addModuleIdent _ c = c

-- ----------------------------------------

mergeMessages' :: [Message] -> [(Position,Token)] -> [([Message],Position,Token)]
mergeMessages' _ [] = []
mergeMessages' [] ((p,t):ps) = ([],p,t) : mergeMessages' [] ps
mergeMessages' mss@(m@(Message mPos x):ms) ((p,t):ps)
    | mPos <= Just p = trace' (show mPos ++ " <= " ++ show (Just p) ++ " Message: " ++ x) ([m],p,t) : mergeMessages' ms ps
    | otherwise = ([],p,t) : mergeMessages' mss ps


tokenNcodes2codes :: [(ModuleIdent,ModuleIdent)] -> Int -> Int -> [([Message],Position,Token)] -> [Code] -> [(Int,Int,Code)]
tokenNcodes2codes _ _ _ [] _ = []
tokenNcodes2codes nameList currLine currCol toks@((messages,Position{line=row,column=col},token):ts) codes
    | currLine < row =
           trace' " NewLine: "
           ((currLine,currCol,NewLine) :
           tokenNcodes2codes nameList (currLine + 1) 1 toks codes)
    | currCol < col =
           trace' (" Space " ++ show (col - currCol))
           ((currLine,currCol,Space (col - currCol)) :
           tokenNcodes2codes nameList currLine col toks codes)
    | isTokenIdentifier token && null codes =
           trace' ("empty Code-List, Token: " ++ show (row,col) ++ show token)
           (addMessage [(currLine,currCol,NotParsed tokenStr)] ++ tokenNcodes2codes nameList newLine newCol ts codes)
    | not (isTokenIdentifier token) =
           trace' (" Token ist kein Identifier: " ++ tokenStr )
           (addMessage [(currLine,currCol,token2code token)] ++ tokenNcodes2codes nameList newLine newCol ts codes)
    | tokenStr == code2string (head codes) =
           trace' (" Code wird genommen: " ++ show (head codes) )
           (addMessage [(currLine,currCol,head codes)] ++ tokenNcodes2codes nameList newLine newCol ts (tail codes))
    | tokenStr == code2qualString (renameModuleIdents nameList (head codes)) =
           let mIdent = maybe Nothing rename (getModuleIdent (head codes))
               lenMod = maybe 0 (length . moduleName) mIdent
               startPos = maybe currCol (const (currCol + lenMod + 1)) mIdent
               symbol = [(currLine,currCol + lenMod,Symbol ".")]
               prefix = maybe []
                              ( (: symbol) .
                                ( \i -> (currLine,
                                         currCol,
                                         ModuleName i)))
                              mIdent in
           trace' (" Code wird genommen: " ++ show (head codes) )
           (addMessage (prefix ++ [(currCol,startPos,head codes)]) ++ tokenNcodes2codes nameList newLine newCol ts (tail codes))
    | elem tokenStr (codeQualifiers (head codes)) =
           trace' (" Token: "++ tokenStr ++" ist Modulname von: " ++ show (head codes) )
           (addMessage [(currLine,currCol,ModuleName (mkMIdent [tokenStr]))] ++
                    tokenNcodes2codes nameList newLine newCol ts codes)
    | otherwise =
           trace' (" Token: "++
                   tokenStr ++
                   ",Code faellt weg:" ++
                   code2string (head codes) ++
                   "|" ++
                   code2qualString (head codes))
           (tokenNcodes2codes nameList currLine currCol toks (tail codes))
  where
      tokenStr = token2string token
      newLine  = (currLine + length (lines tokenStr)) - 1
      newCol   = currCol + length tokenStr

      rename mid = Just $ fromMaybe mid (lookup mid nameList)

      addMessage [] = []
      addMessage ((l,c,code):cs)
         | null messages = (l,c,code):cs
         | otherwise = trace' ("Warning bei code: " ++ show codes ++ ":" ++ show messages)
                              ((l,c,CodeWarning messages code): addMessage cs)
tokenNcodes2codes _ _ _ _ _ = error "SyntaxColoring.tokenNcodes2codes: no pattern match"


renameModuleIdents :: [(ModuleIdent,ModuleIdent)] -> Code -> Code
renameModuleIdents nameList c =
    case c of
        Function x qualIdent -> Function x (rename qualIdent (qualidMod qualIdent))
        Identifier x qualIdent -> Identifier x (rename qualIdent (qualidMod qualIdent))
        _ -> c
  where
    rename x (Nothing) = x
    rename x (Just m) = maybe x (\ m' -> qualifyWith m' (qualidId x)) (lookup m nameList)

{-
codeWithoutUniqueID ::  Code -> String
codeWithoutUniqueID code = maybe (code2string code) (name . unqualify) $ getQualIdent code


codeUnqualify :: Code -> Code
codeUnqualify code = maybe code (setQualIdent code . qualify . unqualify)  $ getQualIdent code
-}

codeQualifiers :: Code -> [String]
codeQualifiers = maybe [] moduleQualifiers . getModuleIdent

getModuleIdent :: Code -> Maybe ModuleIdent
getModuleIdent (ConstructorName _ qualIdent) = qualidMod qualIdent
getModuleIdent (Function _ qualIdent) = qualidMod qualIdent
getModuleIdent (ModuleName moduleIdent) = Just moduleIdent
getModuleIdent (Identifier _ qualIdent) = qualidMod qualIdent
getModuleIdent (TypeConstructor _ qualIdent) = qualidMod qualIdent
getModuleIdent _ = Nothing



{-
setQualIdent :: Code -> QualIdent -> Code
setQualIdent (Keyword str) _ = (Keyword str)
setQualIdent (Space i) _ = (Space i)
setQualIdent NewLine _ = NewLine
setQualIdent (ConstructorName kind _) qualIdent = (ConstructorName kind qualIdent)
setQualIdent (Function kind _) qualIdent = (Function kind qualIdent)
setQualIdent (ModuleName moduleIdent) _ = (ModuleName moduleIdent)
setQualIdent (Commentary str) _ = (Commentary str)
setQualIdent (NumberCode str) _ = (NumberCode str)
setQualIdent (Symbol str) _ = (Symbol str)
setQualIdent (Identifier kind _) qualIdent = (Identifier kind qualIdent)
setQualIdent (TypeConstructor kind _) qualIdent = (TypeConstructor kind qualIdent)
setQualIdent (StringCode str) _ = (StringCode str)
setQualIdent (CharCode str) _ = (CharCode str)
-}

code2string :: Code -> String
code2string (Keyword str) = str
code2string (Space i)= concat (replicate i " ")
code2string NewLine = "\n"
code2string (ConstructorName _ qualIdent) = name $ unqualify qualIdent
code2string (Function _ qualIdent) = name $ unqualify qualIdent
code2string (ModuleName moduleIdent) = moduleName moduleIdent
code2string (Commentary str) = str
code2string (NumberCode str) = str
code2string (Symbol str) = str
code2string (Identifier _ qualIdent) = name $ unqualify qualIdent
code2string (TypeConstructor _ qualIdent) = name $ unqualify qualIdent
code2string (StringCode str) = str
code2string (CharCode str) = str
code2string (NotParsed str) = str
code2string _ = "" -- error / warning

code2qualString :: Code -> String
code2qualString (ConstructorName _ qualIdent) = qualName qualIdent
code2qualString (Function _ qualIdent) = qualName qualIdent
code2qualString (Identifier _ qualIdent) = qualName qualIdent
code2qualString (TypeConstructor _ qualIdent) = qualName qualIdent
code2qualString x = code2string x



token2code :: Token -> Code
token2code tok@(Token cat _)
    | elem cat [IntTok,FloatTok,IntegerTok]
         = NumberCode (token2string tok)
    | elem cat [KW_case,KW_choice,KW_data,KW_do,KW_else,KW_eval,KW_external,
                KW_free,KW_if,KW_import,KW_in,KW_infix,KW_infixl,KW_infixr,
                KW_let,KW_module,KW_newtype,KW_of,KW_rigid,KW_then,KW_type,
                KW_where,Id_as,Id_ccall,Id_forall,Id_hiding,Id_interface,Id_primitive,
                Id_qualified]
         =  Keyword (token2string tok)
    | elem cat [LeftParen,RightParen,Semicolon,LeftBrace,RightBrace,LeftBracket,
                RightBracket,Comma,Underscore,Backquote,
                At,Colon,DotDot,DoubleColon,Equals,Backslash,Bar,LeftArrow,RightArrow,
                Tilde]
         = Symbol (token2string tok)
    | elem cat [LineComment, NestedComment]
         = Commentary (token2string tok)
    | isTokenIdentifier tok
         = Identifier UnknownId $ qualify $ mkIdent $ token2string tok
    | cat == StringTok
         = StringCode (token2string tok)
    | cat == CharTok
         = CharCode (token2string tok)
    | elem cat [EOF,VSemicolon,VRightBrace] = Space 0
    | otherwise = error "SyntaxColoring.token2code: no pattern match"

isTokenIdentifier :: Token -> Bool
isTokenIdentifier (Token cat _) =
  elem cat [Id, QId, Sym, QSym, SymDot, SymMinus, SymMinusDot]

-- DECL Position

getPosition :: Decl -> Position
getPosition (ImportDecl pos _ _ _ _) = pos
getPosition (InfixDecl pos _ _ _) = pos
getPosition (DataDecl pos _ _ _) = pos
getPosition (NewtypeDecl pos _ _ _) = pos
getPosition (TypeDecl pos _ _ _) = pos
getPosition (TypeSig pos _ _) = pos
getPosition (EvalAnnot pos _ _) = pos
getPosition (FunctionDecl pos _ _) = pos
getPosition (ExternalDecl pos _ _ _ _) = pos
getPosition (FlatExternalDecl pos _) = pos
getPosition (PatternDecl pos _ _) = pos
getPosition (ExtraVariables pos _) = pos


lessDecl :: Decl -> Decl -> Bool
lessDecl = (<) `on` getPosition

qsort :: (a -> a -> Bool) -> [a] -> [a]
qsort _ []     = []
qsort less (x:xs) = qsort less [y | y <- xs, less y x] ++ [x] ++ qsort less [y | y <- xs, not $ less y x]


-- DECL TO CODE --------------------------------------------------------------------



exportSpec2codes ::  ExportSpec -> [Code]
exportSpec2codes (Exporting _ exports) = concatMap (export2codes [])  exports

--- @param parse-Exports
--- @param betterParse-Exports
mergeExports2codes :: [Export] -> [Export]  -> [Code]
mergeExports2codes [] _ = []
mergeExports2codes (e:es) xs = concatMap (export2codes xs)  (e:es)


export2codes :: [Export] -> Export -> [Code]
export2codes exports (Export qualIdent)
    | length (filter checkDouble exports) /= 1 =
       [Identifier UnknownId qualIdent]
    | otherwise =
       let [export] = (filter checkDouble exports) in
       export2c export
  where
    checkDouble (ExportTypeWith q _) = eqQualIdent qualIdent q
    checkDouble (Export q) = eqQualIdent qualIdent q
    checkDouble _ = False

    eqQualIdent q1 q2
      | q1 == q2 = True
      | not (isQualified q1) = unqualify q1 == unqualify q2
      | otherwise = False

    export2c (Export qualIdent1) =
         [Function OtherFunctionKind qualIdent1]
    export2c _ =
         [TypeConstructor TypeExport qualIdent]




export2codes _ (ExportTypeWith qualIdent idents) =
     TypeConstructor TypeExport qualIdent : map (Function OtherFunctionKind . qualify) idents
export2codes _ (ExportTypeAll  qualIdent) =
     [TypeConstructor TypeExport qualIdent]
export2codes _ (ExportModule moduleIdent) =
     [ModuleName moduleIdent]

decl2codes :: Decl -> [Code]
decl2codes (ImportDecl _ moduleIdent _ mModuleIdent importSpec) =
     [ModuleName moduleIdent] ++
     maybe [] ((:[]) . ModuleName) mModuleIdent ++
     maybe [] (importSpec2codes moduleIdent)  importSpec
decl2codes (InfixDecl _ _ _ idents) =
     map (Function InfixFunction . qualify) idents
decl2codes (DataDecl _ ident idents constrDecls) =
     TypeConstructor TypeDecla (qualify ident) :
     map (Identifier UnknownId . qualify) idents ++
     concatMap constrDecl2codes constrDecls
decl2codes (NewtypeDecl _ _ _ _) =
     []
decl2codes (TypeDecl _ ident idents typeExpr) =
     TypeConstructor TypeDecla (qualify ident) :
     map (Identifier UnknownId . qualify) idents ++
     typeExpr2codes typeExpr
decl2codes (TypeSig _ idents typeExpr) =
     map (Function TypSig . qualify) idents ++ typeExpr2codes typeExpr
decl2codes (EvalAnnot _ idents _) =
     map (Function FunDecl . qualify) idents
decl2codes (FunctionDecl _ _ equations) =
     concatMap equation2codes equations
decl2codes (ExternalDecl _ _ _ _ _) =
     []
decl2codes (FlatExternalDecl _ idents) =
     map (Function FunDecl . qualify) idents
decl2codes (PatternDecl _ constrTerm rhs) =
     constrTerm2codes constrTerm ++ rhs2codes rhs
decl2codes (ExtraVariables _ idents) =
     map (Identifier IdDecl . qualify) idents

equation2codes :: Equation -> [Code]
equation2codes (Equation _ lhs rhs) =
     lhs2codes lhs ++ rhs2codes rhs

lhs2codes :: Lhs -> [Code]
lhs2codes (FunLhs ident constrTerms) =
    Function FunDecl (qualify ident) : concatMap constrTerm2codes constrTerms
lhs2codes (OpLhs constrTerm1 ident constrTerm2) =
    constrTerm2codes constrTerm1 ++ [Function FunDecl $ qualify ident] ++ constrTerm2codes constrTerm2
lhs2codes (ApLhs lhs constrTerms) =
    lhs2codes lhs ++ concatMap constrTerm2codes constrTerms

rhs2codes :: Rhs -> [Code]
rhs2codes (SimpleRhs _ expression decls) =
    expression2codes expression ++ concatMap decl2codes decls
rhs2codes (GuardedRhs condExprs decls) =
    concatMap condExpr2codes condExprs ++ concatMap decl2codes decls

condExpr2codes :: CondExpr -> [Code]
condExpr2codes (CondExpr _ expression1 expression2) =
   expression2codes expression1 ++ expression2codes expression2

constrTerm2codes :: ConstrTerm -> [Code]
constrTerm2codes (LiteralPattern _) = []
constrTerm2codes (NegativePattern _ _) = []
constrTerm2codes (VariablePattern ident) = [Identifier IdDecl (qualify ident)]
constrTerm2codes (ConstructorPattern qualIdent constrTerms) =
    ConstructorName ConstrPattern qualIdent : concatMap constrTerm2codes constrTerms
constrTerm2codes (InfixPattern constrTerm1 qualIdent constrTerm2) =
    constrTerm2codes constrTerm1 ++ [ConstructorName ConstrPattern qualIdent] ++ constrTerm2codes constrTerm2
constrTerm2codes (ParenPattern constrTerm) = constrTerm2codes constrTerm
constrTerm2codes (TuplePattern _ constrTerms) = concatMap constrTerm2codes constrTerms
constrTerm2codes (ListPattern _ constrTerms) = concatMap constrTerm2codes constrTerms
constrTerm2codes (AsPattern ident constrTerm) =
    Function OtherFunctionKind (qualify ident) : constrTerm2codes constrTerm
constrTerm2codes (LazyPattern _ constrTerm) = constrTerm2codes constrTerm
constrTerm2codes (FunctionPattern qualIdent constrTerms) =
    Function OtherFunctionKind qualIdent : concatMap constrTerm2codes constrTerms
constrTerm2codes (InfixFuncPattern constrTerm1 qualIdent constrTerm2) =
    constrTerm2codes constrTerm1 ++ [Function InfixFunction qualIdent] ++ constrTerm2codes constrTerm2
constrTerm2codes (RecordPattern _ _) =
  error "SyntaxColoring.constrTerm2codes: record pattern"

expression2codes :: Expression -> [Code]
expression2codes (Literal _) = []
expression2codes (Variable qualIdent) =
    [Identifier IdOccur qualIdent]
expression2codes (Constructor qualIdent) =
    [ConstructorName ConstrCall qualIdent]
expression2codes (Paren expression) =
    expression2codes expression
expression2codes (Typed expression typeExpr) =
    expression2codes expression ++ typeExpr2codes typeExpr
expression2codes (Tuple _ expressions) =
    concatMap expression2codes expressions
expression2codes (List _ expressions) =
    concatMap expression2codes expressions
expression2codes (ListCompr _ expression statements) =
    expression2codes expression ++ concatMap statement2codes statements
expression2codes (EnumFrom expression) =
    expression2codes expression
expression2codes (EnumFromThen expression1 expression2) =
    expression2codes expression1 ++ expression2codes expression2
expression2codes (EnumFromTo expression1 expression2) =
    expression2codes expression1 ++ expression2codes expression2
expression2codes (EnumFromThenTo expression1 expression2 expression3) =
    expression2codes expression1 ++
    expression2codes expression2 ++
    expression2codes expression3
expression2codes (UnaryMinus ident expression) =
    Symbol (name ident) : expression2codes expression
expression2codes (Apply expression1 expression2) =
    expression2codes expression1 ++ expression2codes expression2
expression2codes (InfixApply expression1 infixOp expression2) =
    expression2codes expression1 ++ infixOp2codes infixOp ++ expression2codes expression2
expression2codes (LeftSection expression infixOp) =
    expression2codes expression ++ infixOp2codes infixOp
expression2codes (RightSection infixOp expression) =
    infixOp2codes infixOp ++ expression2codes expression
expression2codes (Lambda _ constrTerms expression) =
    concatMap constrTerm2codes constrTerms ++ expression2codes expression
expression2codes (Let decls expression) =
    concatMap decl2codes decls ++ expression2codes expression
expression2codes (Do statements expression) =
    concatMap statement2codes statements ++ expression2codes expression
expression2codes (IfThenElse _ expression1 expression2 expression3) =
    expression2codes expression1 ++ expression2codes expression2 ++ expression2codes expression3
expression2codes (Case _ expression alts) =
    expression2codes expression ++ concatMap alt2codes alts
expression2codes _ = error "SyntaxColoring.expression2codes: no pattern match"

infixOp2codes :: InfixOp -> [Code]
infixOp2codes (InfixOp qualIdent) = [Function InfixFunction qualIdent]
infixOp2codes (InfixConstr qualIdent) = [ConstructorName OtherConstrKind qualIdent]


statement2codes :: Statement -> [Code]
statement2codes (StmtExpr _ expression) =
    expression2codes expression
statement2codes (StmtDecl decls) =
    concatMap decl2codes decls
statement2codes (StmtBind _ constrTerm expression) =
     constrTerm2codes constrTerm ++ expression2codes expression


alt2codes :: Alt -> [Code]
alt2codes (Alt _ constrTerm rhs) =
    constrTerm2codes constrTerm ++ rhs2codes rhs

constrDecl2codes :: ConstrDecl -> [Code]
constrDecl2codes (ConstrDecl _ _ ident typeExprs) =
    ConstructorName ConstrDecla (qualify ident) : concatMap typeExpr2codes typeExprs
constrDecl2codes (ConOpDecl _ _ typeExpr1 ident typeExpr2) =
    typeExpr2codes typeExpr1 ++ [ConstructorName ConstrDecla $ qualify ident] ++ typeExpr2codes typeExpr2


importSpec2codes :: ModuleIdent -> ImportSpec -> [Code]
importSpec2codes moduleIdent (Importing _ imports) = concatMap (import2codes moduleIdent) imports
importSpec2codes moduleIdent (Hiding _ imports) = concatMap (import2codes moduleIdent) imports

import2codes :: ModuleIdent -> Import -> [Code]
import2codes moduleIdent (Import ident) =
     [Function OtherFunctionKind $ qualifyWith moduleIdent ident]
import2codes moduleIdent (ImportTypeWith ident idents) =
     ConstructorName OtherConstrKind (qualifyWith moduleIdent ident) :
     map (Function OtherFunctionKind . qualifyWith moduleIdent) idents
import2codes moduleIdent (ImportTypeAll  ident) =
     [ConstructorName OtherConstrKind $ qualifyWith moduleIdent ident]

typeExpr2codes :: TypeExpr -> [Code]
typeExpr2codes (ConstructorType qualIdent typeExprs) =
    TypeConstructor TypeUse qualIdent : concatMap typeExpr2codes typeExprs
typeExpr2codes (VariableType ident) =
    [Identifier IdOccur (qualify ident)]
typeExpr2codes (TupleType typeExprs) =
    concatMap typeExpr2codes typeExprs
typeExpr2codes (ListType typeExpr) =
    typeExpr2codes typeExpr
typeExpr2codes (ArrowType typeExpr1 typeExpr2) =
    typeExpr2codes typeExpr1 ++ typeExpr2codes typeExpr2
typeExpr2codes (RecordType _ _) = error "SyntaxColoring.typeExpr2codes: Record pattern"

-- TOKEN TO STRING ------------------------------------------------------------
token2string :: Token -> [Char]
token2string (Token Id a) = attributes2string a
token2string (Token QId a) = attributes2string a
token2string (Token Sym a) = attributes2string a
token2string (Token QSym a) = attributes2string a
token2string (Token IntTok a) = attributes2string a
token2string (Token FloatTok a) = attributes2string a
token2string (Token CharTok a) = attributes2string a
token2string (Token IntegerTok a) = attributes2string a
token2string (Token StringTok a) = attributes2string a
token2string (Token LeftParen _) = "("
token2string (Token RightParen _) = ")"
token2string (Token Semicolon _) = ";"
token2string (Token LeftBrace _) = "{"
token2string (Token RightBrace _) = "}"
token2string (Token LeftBracket _) = "["
token2string (Token RightBracket _) = "]"
token2string (Token Comma _) = ","
token2string (Token Underscore _) = "_"
token2string (Token Backquote _) = "`"
token2string (Token VSemicolon _) = ""
token2string (Token VRightBrace _) = ""
token2string (Token At _) = "@"
token2string (Token Colon _) = ":"
token2string (Token DotDot _) = ".."
token2string (Token DoubleColon _) = "::"
token2string (Token Equals _) = "="
token2string (Token Backslash _) = "\\"
token2string (Token Bar _) = "|"
token2string (Token LeftArrow _) = "<-"
token2string (Token RightArrow _) = "->"
token2string (Token Tilde _) = "~"
token2string (Token SymDot _) = "."
token2string (Token SymMinus _) = "-"
token2string (Token SymMinusDot _) = "-."
token2string (Token KW_case _) = "case"
token2string (Token KW_choice _) = "choice"
token2string (Token KW_data _) = "data"
token2string (Token KW_do _) = "do"
token2string (Token KW_else _) = "else"
token2string (Token KW_eval _) = "eval"
token2string (Token KW_external _) = "external"
token2string (Token KW_free _) = "free"
token2string (Token KW_if _) = "if"
token2string (Token KW_import _) = "import"
token2string (Token KW_in _) = "in"
token2string (Token KW_infix _) = "infix"
token2string (Token KW_infixl _) = "infixl"
token2string (Token KW_infixr _) = "infixr"
token2string (Token KW_let _) = "let"
token2string (Token KW_module _) = "module"
token2string (Token KW_newtype _) = "newtype"
token2string (Token KW_of _) = "of"
token2string (Token KW_rigid _) = "rigid"
token2string (Token KW_then _) = "then"
token2string (Token KW_type _) = "type"
token2string (Token KW_where _) = "where"
token2string (Token Id_as _) = "as"
token2string (Token Id_ccall _) = "ccall"
token2string (Token Id_forall _) = "forall"
token2string (Token Id_hiding _) = "hiding"
token2string (Token Id_interface _) = "interface"
token2string (Token Id_primitive _) = "primitive"
token2string (Token Id_qualified _) = "qualified"
token2string (Token EOF _) = ""
token2string (Token LineComment (StringAttributes sv _)) = sv
token2string (Token LineComment a) = attributes2string a
token2string (Token NestedComment (StringAttributes sv _)) = sv
token2string (Token NestedComment a) = attributes2string a
token2string (Token LeftBraceSemicolon _) = "{;"
token2string (Token Binds _) = ":="
token2string (Token Pragma a) = "{-#" ++ attributes2string a ++ "#-}"

attributes2string :: Attributes -> [Char]
attributes2string NoAttributes = ""
attributes2string (CharAttributes cv _) = showCh cv
attributes2string (IntAttributes iv _) = show iv
attributes2string (FloatAttributes fv _) = show fv
attributes2string (IntegerAttributes iv _) = show iv
attributes2string (StringAttributes sv _) = showSt sv
attributes2string (IdentAttributes mIdent ident) =concat (intersperse "." (mIdent ++ [ident]))

showCh :: Char -> [Char]
showCh c
   | c == '\\' = "'\\\\'"
   | elem c ('\127' : ['\001' .. '\031']) = show c
   | otherwise = toString c
  where
    toString c' = '\'' : c' : "'"

showSt :: [Char] -> [Char]
showSt = addQuotes . concatMap toGoodChar
   where
      addQuotes x = "\"" ++ x ++ "\""

toGoodChar :: Char -> [Char]
toGoodChar c
   | c == '\\' = "\\\\"
   | elem c ('\127' : ['\001' .. '\031']) = justShow c
   | c == '"' = "\\\""
   | otherwise = c : ""
 where
     justShow = init . tail . show