{-# LANGUAGE FlexibleContexts, FlexibleInstances, ScopedTypeVariables, OverloadedStrings #-}
{-# OPTIONS_GHC -Wno-orphans #-}

module Main where

import Prelude hiding (readFile)
import qualified Data.ByteString.Char8 as B
import qualified Data.ByteString.Lazy.Char8 as LB
import Data.Text.Encoding (encodeUtf8, decodeUtf8With)
import Data.Text.Encoding.Error (replace)

import Text.PrettyPrint (render)

import System.Console.GetOpt
import System.IO
import System.Environment
import System.Directory
import System.FilePath
import Text.PrettyPrint.GenericPretty (pp, pretty, Out)
import Text.Read (readMaybe)
import Data.List (sortBy, intercalate, (\\), isSuffixOf)
import Data.Ord (comparing)
import Data.Char (toLower)
import Data.Maybe (listToMaybe, fromMaybe, maybeToList)
import Data.Data
import Data.Generics.Uniplate.Data

import Language.Fortran.ParserMonad (selectFortranVersion, FortranVersion(..), fromRight)
import qualified Language.Fortran.Lexer.FixedForm as FixedForm (collectFixedTokens, Token(..))
import qualified Language.Fortran.Lexer.FreeForm as FreeForm (collectFreeTokens, Token(..))

import Language.Fortran.Parser.Any

import Language.Fortran.Util.ModFile
import Language.Fortran.Util.Position

import Language.Fortran.PrettyPrint
import Language.Fortran.Analysis
import Language.Fortran.AST
import Language.Fortran.Analysis.Types
import Language.Fortran.Analysis.BBlocks
import Language.Fortran.Analysis.DataFlow
import Language.Fortran.Analysis.Renaming
import Data.Graph.Inductive hiding (trc, mf, version)

import qualified Data.IntMap as IM
import qualified Data.Map as M
import Control.Monad
import Text.Printf

programName :: String
programName = "fortran-src"

main :: IO ()
main = do
  args <- getArgs
  (opts, parsedArgs) <- compileArgs args
  case (parsedArgs, action opts) of
    ([path], actionOpt) -> do
      contents <- flexReadFile path
      let version = fromMaybe (deduceVersion path) (fortranVersion opts)
      let (Just parserF0) = lookup version parserWithModFilesVersions
      let parserF m b s = fromRight (parserF0 m b s)
      let outfmt = outputFormat opts
      mods <- decodeModFiles $ includeDirs opts
      let mmap = combinedModuleMap mods
      let tenv = combinedTypeEnv mods
      let pvm = combinedParamVarMap mods

      let runTypes = analyseAndCheckTypesWithEnv tenv . analyseRenamesWithModuleMap mmap . initAnalysis
      let runRenamer = stripAnalysis . rename . analyseRenamesWithModuleMap mmap . initAnalysis
      let runBBlocks pf = showBBlocks pf' ++ "\n\n" ++ showDataFlow pf'
            where pf' = analyseParameterVars pvm . analyseBBlocks . analyseRenamesWithModuleMap mmap . initAnalysis $ pf
      let runSuperGraph pf | outfmt == DOT = superBBGrToDOT sgr
                           | otherwise     = superGraphDataFlow pf' sgr
            where pf' = analyseParameterVars pvm . analyseBBlocks . analyseRenamesWithModuleMap mmap . initAnalysis $ pf
                  bbm = genBBlockMap pf'
                  sgr = genSuperBBGr bbm
      let runCompile = encodeModFile . genModFile . fst . analyseTypesWithEnv tenv . analyseRenamesWithModuleMap mmap . initAnalysis
      let findBlockPU pf astBlockId = listToMaybe
            [ pu | pu <- universeBi pf :: [ProgramUnit (Analysis A0)]
                 , bbgr <- maybeToList (bBlocks (getAnnotation pu))
                 , b <- concatMap snd $ labNodes (bbgrGr bbgr)
                 , insLabel (getAnnotation b) == Just astBlockId ]
      case actionOpt of
        Lex | version `elem` [ Fortran66, Fortran77, Fortran77Extended, Fortran77Legacy ] ->
          print $ FixedForm.collectFixedTokens version contents
        Lex | version `elem` [Fortran90, Fortran2003, Fortran2008] ->
          print $ FreeForm.collectFreeTokens version contents
        Lex        -> ioError $ userError $ usageInfo programName options
        Parse      -> pp $ parserF mods contents path
        Typecheck  -> let (pf, _, errs) = runTypes (parserF mods contents path) in
                        printTypeErrors errs >> printTypes (extractTypeEnv pf)
        Rename     -> pp . runRenamer $ parserF mods contents path
        BBlocks    -> putStrLn . runBBlocks $ parserF mods contents path
        SuperGraph -> putStrLn . runSuperGraph $ parserF mods contents path
        Reprint    -> putStrLn . render . flip (pprint version) (Just 0) $ parserF mods contents path
        Compile    -> do
          let bytes = runCompile $ parserF mods contents path
          let fspath = path <.> modFileSuffix
          LB.writeFile fspath bytes
        DumpModFile -> do
          let path' = if modFileSuffix `isSuffixOf` path then path else path <.> modFileSuffix
          contents' <- LB.readFile path'
          case decodeModFile contents' of
            Left msg -> putStrLn $ "Error: " ++ msg
            Right mf -> putStrLn $ "Filename: " ++ moduleFilename mf ++
                                   "\n\nStringMap:\n" ++ showStringMap (combinedStringMap [mf]) ++
                                   "\n\nModuleMap:\n" ++ showModuleMap (combinedModuleMap [mf]) ++
                                   "\n\nDeclMap:\n" ++ showGenericMap (combinedDeclMap [mf]) ++
                                   "\n\nTypeEnv:\n" ++ showTypes (combinedTypeEnv [mf]) ++
                                   "\n\nParamVarMap:\n" ++ showGenericMap (combinedParamVarMap [mf]) ++
                                   "\n\nOther Data Labels: " ++ show (getLabelsModFileData mf)
        ShowFlows isFrom isSuper astBlockId -> do
          let pf = analyseParameterVars pvm .
                   analyseBBlocks .
                   analyseRenamesWithModuleMap mmap .
                   initAnalysis $ parserF mods contents path
          let bbm = genBBlockMap pf
          case (isSuper, findBlockPU pf astBlockId) of
            (False, Nothing) -> fail "Couldn't find given AST block ID number."
            (False, Just pu)
              | Just bbgr <- M.lookup (puName pu) bbm ->
                  putStrLn $ showFlowsDOT pf bbgr astBlockId isFrom
              | otherwise -> do
                  print $ M.keys bbm
                  fail $ "Internal error: Program Unit " ++ show (puName pu) ++ " is lacking a basic block graph."
            (True, _) -> do
              let sgr = genSuperBBGr bbm
              putStrLn $ showFlowsDOT pf (superBBGrGraph sgr) astBlockId isFrom
        ShowBlocks mlinenum -> do
          let pf = analyseBBlocks .
                   analyseRenamesWithModuleMap mmap .
                   initAnalysis $ parserF mods contents path
          let f :: ([ASTBlockNode], Int) -> ([ASTBlockNode], Int) -> ([ASTBlockNode], Int)
              f (nodes1, len1) (nodes2, len2)
                | len1 < len2 = (nodes1, len1)
                | len2 < len1 = (nodes2, len2)
                | otherwise   = (nodes1 ++ nodes2, len1)
          let lineMap :: IM.IntMap ([ASTBlockNode], Int)  -- ([list of IDs], line-distance of span)
              lineMap = IM.fromListWith f [
                (l, ([i], lineDistance ss))
                | b <- universeBi pf :: [Block (Analysis A0)]
                , i <- maybeToList . insLabel $ getAnnotation b
                , let ss = getSpan b
                , l <- spannedLines ss
                ]
          case mlinenum of
            Just l -> putStrLn . unwords . map show $ fromMaybe [] (fst <$> IM.lookup l lineMap)
            Nothing -> do
              let lineBs = B.lines contents
              let maxLen = maximum (0:map B.length lineBs)
              forM_ (zip lineBs [1..]) $ \ (line, l) -> do
                let nodeIDs = fromMaybe [] (fst <$> IM.lookup l lineMap)
                let nodeStr = B.intercalate "," (map (B.pack . ('B':) . show) nodeIDs)
                let suffix | null nodeIDs = ""
                           | otherwise    = B.replicate (maxLen - B.length line + 1) ' ' <> "!" <> nodeStr
                B.putStrLn $ line <> suffix
    _ -> fail $ usageInfo programName options

-- List files in dir recursively
rGetDirContents :: String -> IO [String]
rGetDirContents d = canonicalizePath d >>= \d' -> go [d'] d'
  where
  go seen d'' = do
    ds <- getDirectoryContents d''
    fmap concat . mapM f $ ds \\ [".", ".."] -- remove '.' and '..' entries
      where
        f x = do
          path <- canonicalizePath $ d ++ "/" ++ x
          g <- doesDirectoryExist path
          if g && notElem path seen then do
            x' <- go (path : seen) path
            return $ map (\ y -> x ++ "/" ++ y) x'
          else return [x]

-- List files in dir
getDirContents :: String -> IO [String]
getDirContents d = do
  d' <- canonicalizePath d
  map (d' </>) `fmap` listDirectory d'

decodeModFiles :: [String] -> IO ModFiles
decodeModFiles = foldM (\ modFiles d -> do
      -- Figure out the camfort mod files and parse them.
      modFileNames <- filter isModFile `fmap` getDirContents d
      addedModFiles <- forM modFileNames $ \ modFileName -> do
        contents <- LB.readFile (d </> modFileName)
        case decodeModFile contents of
          Left msg -> do
            hPutStrLn stderr $ modFileName ++ ": Error: " ++ msg
            return emptyModFile
          Right modFile -> do
            hPutStrLn stderr $ modFileName ++ ": successfully parsed precompiled file."
            return modFile
      return $ addedModFiles ++ modFiles
    ) emptyModFiles

isModFile :: FilePath -> Bool
isModFile = (== modFileSuffix) . takeExtension

superGraphDataFlow :: forall a. (Out a, Data a) => ProgramFile (Analysis a) -> SuperBBGr (Analysis a) -> String
superGraphDataFlow pf sgr = showBBGr (bbgrMap (nmap (map (fmap insLabel))) gr') ++ "\n\n" ++ replicate 50 '-' ++ "\n\n" ++
                            show entries ++ "\n\n" ++ replicate 50 '-' ++ "\n\n" ++
                            dfStr gr'
  where
    gr' = superBBGrGraph sgr
    entries = superBBGrEntries sgr
    dfStr gr = (\ (l, x) -> '\n':l ++ ": " ++ x) =<< [
                 ("callMap",      show cm)
               , ("entries",      show (bbgrEntries gr))
               , ("exits",        show (bbgrExits gr))
               , ("postOrder",    show (postOrder gr))
               , ("revPostOrder", show (revPostOrder gr))
               , ("revPreOrder",  show (revPreOrder gr))
               , ("dominators",   show (dominators gr))
               , ("iDominators",  show (iDominators gr))
               , ("defMap",       show dm)
               , ("lva",          show (IM.toList $ lva gr))
               , ("rd",           show (IM.toList rDefs))
               , ("backEdges",    show bedges)
               , ("topsort",      show (topsort $ bbgrGr gr))
               , ("scc ",         show (scc $ bbgrGr gr))
               , ("loopNodes",    show (loopNodes bedges $ bbgrGr gr))
               , ("duMap",        show (genDUMap bm dm gr rDefs))
               , ("udMap",        show (genUDMap bm dm gr rDefs))
               , ("flowsTo",      show (edges flTo))
               , ("varFlowsTo",   show (genVarFlowsToMap dm flTo))
               , ("ivMap",        show (genInductionVarMap bedges gr))
               , ("blockMap",     unlines [ "AST-block " ++ show i ++ ":\n" ++ pretty b | (i, b) <- IM.toList bm ])
               , ("derivedInd",   unlines [ "Expression " ++ show i ++ " (IE: " ++ show ie ++ "):\n" ++ pretty e
                                          | e <- universeBi bm :: [Expression (Analysis a)]
                                          , i <- maybeToList (insLabel (getAnnotation e))
                                          , let ie = IM.lookup i diMap ])
               , ("constExpMap",  show (genConstExpMap pf))
               ] where
                   bedges = genBackEdgeMap (dominators gr) $ bbgrGr gr
                   flTo   = genFlowsToGraph bm dm gr rDefs
                   rDefs  = rd gr
                   diMap  = genDerivedInductionMap bedges gr
    lva = liveVariableAnalysis
    bm = genBlockMap pf
    dm = genDefMap bm
    rd = reachingDefinitions dm
    cm = genCallMap pf

showGenericMap :: (Show a, Show b) => M.Map a b -> String
showGenericMap = unlines . map (\ (k, v) -> show k ++ " : " ++ show v) . M.toList
showStringMap :: StringMap -> String
showStringMap = showGenericMap
showModuleMap :: ModuleMap -> String
showModuleMap = concatMap (\ (n, m) -> show n ++ ":\n" ++ (unlines . map ("  "++) . lines . showGenericMap $ m)) . M.toList
showTypes :: TypeEnv -> String
showTypes tenv = flip concatMap (M.toList tenv) $ \ (name, IDType { idVType = vt, idCType = ct }) ->
    printf "%s\t\t%s %s\n" name (drop 4 $ maybe "  -" show vt) (drop 2 $ maybe "   " show ct)
printTypes :: TypeEnv -> IO ()
printTypes = putStrLn . showTypes
showTypeErrors :: [TypeError] -> String
showTypeErrors errs = unlines [ show ss ++ ": " ++ msg | (msg, ss) <- sortBy (comparing snd) errs ]
printTypeErrors :: [TypeError] -> IO ()
printTypeErrors = putStrLn . showTypeErrors

data Action
  = Lex | Parse | Typecheck | Rename | BBlocks | SuperGraph | Reprint | DumpModFile | Compile
  | ShowFlows Bool Bool Int | ShowBlocks (Maybe Int)
  deriving Eq

instance Read Action where
  readsPrec _ value =
    let options' = [ ("lex", Lex) , ("parse", Parse) ] in
      tryTypes options'
      where
        tryTypes [] = []
        tryTypes ((attempt,result):xs) =
          if map toLower value == attempt then [(result, "")] else tryTypes xs

data OutputFormat = Default | DOT deriving Eq

data Options = Options
  { fortranVersion  :: Maybe FortranVersion
  , action          :: Action
  , outputFormat    :: OutputFormat
  , includeDirs     :: [String] }

initOptions :: Options
initOptions = Options Nothing Parse Default []

options :: [OptDescr (Options -> Options)]
options =
  [ Option ['v','F']
      ["fortranVersion"]
      (ReqArg (\v opts -> opts { fortranVersion = selectFortranVersion v }) "VERSION")
      "Fortran version to use, format: Fortran[66/77/77Legacy/77Extended/90]"
  , Option ['a']
      ["action"]
      (ReqArg (\a opts -> opts { action = read a }) "ACTION")
      "lex or parse action"
  , Option ['t']
      ["typecheck"]
      (NoArg $ \ opts -> opts { action = Typecheck })
      "parse and run typechecker"
  , Option ['R']
      ["rename"]
      (NoArg $ \ opts -> opts { action = Rename })
      "parse and rename variables"
  , Option ['B']
      ["bblocks"]
      (NoArg $ \ opts -> opts { action = BBlocks })
      "analyse basic blocks"
  , Option ['S']
      ["supergraph"]
      (NoArg $ \ opts -> opts { action = SuperGraph })
      "analyse super graph of basic blocks"
  , Option ['r']
      ["reprint"]
      (NoArg $ \ opts -> opts { action = Reprint })
      "Parse and output using pretty printer"
  , Option []
      ["dot"]
      (NoArg $ \ opts -> opts { outputFormat = DOT })
      "output graphs in GraphViz DOT format"
  , Option []
      ["dump-mod-file"]
      (NoArg $ \ opts -> opts { action = DumpModFile })
      "dump the information contained within mod files"
  , Option ['I']
      ["include-dir"]
      (ReqArg (\ d opts -> opts { includeDirs = d:includeDirs opts }) "DIR")
      "directory to search for precompiled 'mod files'"
  , Option ['c']
      ["compile"]
      (NoArg $ \ opts -> opts { action = Compile })
      "compile an .fsmod file from the input"
  , Option []
      ["show-block-numbers"]
      (OptArg (\a opts -> opts { action = ShowBlocks (a >>= readMaybe) }
              ) "LINE-NUM")
      "Show the corresponding AST-block identifier number next to every line of code."
  , Option []
      ["show-flows-to"]
      (ReqArg (\a opts -> case a of s:num | toLower s == 's' -> opts { action = ShowFlows False True (read num) }
                                    b:num | toLower b == 'b' -> opts { action = ShowFlows False False (read num) }
                                    num                      -> opts { action = ShowFlows False False (read num) }
              ) "AST-BLOCK-ID")
      "dump a graph showing flows-to information from the given AST-block ID; prefix with 's' for supergraph"
  , Option []
      ["show-flows-from"]
      (ReqArg (\a opts -> case a of s:num | toLower s == 's' -> opts { action = ShowFlows True True (read num) }
                                    b:num | toLower b == 'b' -> opts { action = ShowFlows True False (read num) }
                                    num                      -> opts { action = ShowFlows True False (read num) }
              ) "AST-BLOCK-ID")
      "dump a graph showing flows-from information from the given AST-block ID; prefix with 's' for supergraph"
  ]

compileArgs :: [ String ] -> IO (Options, [ String ])
compileArgs args =
  case getOpt Permute options args of
    (o, n, []) -> return (foldl (flip id) initOptions o, n)
    (_, _, errors) -> ioError $ userError $ concat errors ++ usageInfo header options
  where
    header = "Usage: " ++ programName ++ " [OPTION...] <file>"

instance {-# OVERLAPPING #-} Show [ FixedForm.Token ] where
  show = unlines . lines'
    where
      lines' [] = []
      lines' xs =
        let (x, xs') = break isNewline xs
        in case xs' of
             (nl@(FixedForm.TNewline _):xs'') -> ('\t' : (intercalate ", " . map show $ x ++ [nl])) : lines' xs''
             xs'' -> [ show xs'' ]
      isNewline (FixedForm.TNewline _) = True
      isNewline _ = False

instance {-# OVERLAPPING #-} Show [ FreeForm.Token ] where
  show = unlines . lines'
    where
      lines' [] = []
      lines' xs =
        let (x, xs') = break isNewline xs
        in case xs' of
             (nl@(FreeForm.TNewline _):xs'') -> ('\t' : (intercalate ", " . map show $ x ++ [nl])) : lines' xs''
             xs'' -> [ show xs'' ]
      isNewline (FreeForm.TNewline _) = True
      isNewline _ = False

flexReadFile :: String -> IO B.ByteString
flexReadFile = fmap (encodeUtf8 . decodeUtf8With (replace ' ')) . B.readFile