----------------------------------------------------------------------
-- |
-- Module      : Compile
-- Maintainer  : AR
-- Stability   : (stable)
-- Portability : (portable)
--
-- > CVS $Date: 2005/09/18 22:55:46 $
-- > CVS $Author: aarne $
-- > CVS $Revision: 1.42 $
--
-- The top-level compilation chain from source file to gfc\/gfr.
-----------------------------------------------------------------------------

module GF.Compile.Compile (compileModule, compileEnvShSt, compileOne,
		CompileEnv, TimedCompileEnv,gfGrammarPathVar,pathListOpts,
	       getGFEFiles) where

import GF.Grammar.Grammar
import GF.Infra.Ident
import GF.Infra.Option
import GF.Grammar.PrGrammar
import GF.Compile.Update
import GF.Grammar.Lookup
import GF.Infra.Modules
import GF.Infra.ReadFiles
import GF.Compile.ShellState
import GF.Compile.MkResource
---- import MkUnion

-- the main compiler passes
import GF.Compile.GetGrammar
import GF.Compile.Extend
import GF.Compile.Rebuild
import GF.Compile.Rename
import GF.Grammar.Refresh
import GF.Compile.CheckGrammar
import GF.Compile.Optimize
import GF.Compile.GrammarToCanon
import GF.Canon.Share
import GF.Canon.Subexpressions (elimSubtermsMod)

import qualified GF.Canon.CanonToGrammar as CG

import qualified GF.Canon.GFC as GFC
import qualified GF.Canon.MkGFC as MkGFC
import GF.Canon.GetGFC

import GF.Data.Operations
import GF.Infra.UseIO
import GF.System.Arch

import Control.Monad
import System.Directory

-- | environment variable for grammar search path
gfGrammarPathVar = "GF_GRAMMAR_PATH"

-- | in batch mode: write code in a file
batchCompile f = liftM fst $ compileModule defOpts emptyShellState f
  where
    defOpts = options [emitCode] 
batchCompileOpt f = liftM fst $ compileModule defOpts emptyShellState f
  where
    defOpts = options [emitCode, optimizeCanon] 

batchCompileOld f = compileOld defOpts f
  where
    defOpts = options [emitCode] 

-- | compile with one module as starting point
-- command-line options override options (marked by --#) in the file
-- As for path: if it is read from file, the file path is prepended to each name.
-- If from command line, it is used as it is.
compileModule :: Options -> ShellState -> FilePath -> IOE TimedCompileEnv
----             IOE (GFC.CanonGrammar, (SourceGrammar,[(FilePath,ModTime)]))

compileModule opts st0 file | 
     oElem showOld opts || 
     elem suff ["cf","ebnf"] = do
  let putp  = putPointE opts
  let putpp = putPointEsil opts
  let path = [] ----
  grammar1 <- if suff == "cf"
              then putp ("- parsing" +++ suff +++ file) $ getCFGrammar opts file
              else if suff == "ebnf"
              then putp ("- parsing" +++ suff +++ file) $ getEBNFGrammar opts file
              else putp ("- parsing old gf" +++ file) $ getOldGrammar opts file
  let mods = modules grammar1
  let env = compileEnvShSt st0 []
  foldM (comp putpp path) env mods
 where
   suff = fileSuffix file
   comp putpp path env sm0 = do
     (k',sm)  <- makeSourceModule opts (fst env) sm0
     cm  <- putpp "  generating code... " $ generateModuleCode opts path sm
     ft <- getReadTimes file ---
     extendCompileEnvInt env (k',sm,cm) ft

compileModule opts1 st0 file = do
  opts0 <- ioeIO $ getOptionsFromFile file
  let useFileOpt = maybe False (const True) $ getOptVal opts0 pathList
  let useLineOpt = maybe False (const True) $ getOptVal opts1 pathList
  let opts = addOptions opts1 opts0 
  let fpath = justInitPath file
  ps0 <- ioeIO $ pathListOpts opts fpath

  let ps1 = if (useFileOpt && not useLineOpt) 
              then (map (prefixPathName fpath) ps0)
              else ps0
  ps <- ioeIO $ extendPathEnv gfLibraryPath gfGrammarPathVar ps1
  let ioeIOIf = if oElem beVerbose opts then ioeIO else (const (return ()))
  ioeIOIf $ putStrLn $ "module search path:" +++ show ps ----
  let st = st0 --- if useFileOpt then emptyShellState else st0
  let rfs = readFiles st
  let file' = if useFileOpt then justFileName file else file -- to find file itself
  files <- getAllFiles opts ps rfs file'
  ioeIOIf $ putStrLn $ "files to read:" +++ show files ----
  let names = map justModuleName files
  ioeIOIf $ putStrLn $ "modules to include:" +++ show names ----
  let env0 = compileEnvShSt st names
  (e,mm) <- foldIOE (compileOne opts) env0 files
  maybe (return ()) putStrLnE mm
  return e

getReadTimes file = do
  t <- ioeIO getNowTime
  let m = justModuleName file
  return $ (m,t) : [(resModName m,t) | not (isGFC file)]

compileEnvShSt :: ShellState -> [ModName] -> TimedCompileEnv
compileEnvShSt st fs = ((0,sgr,cgr),fts) where
  cgr = MGrammar [m | m@(i,_) <- modules (canModules st), notInc i]
  sgr = MGrammar [m | m@(i,_) <- modules (srcModules st), notIns i]
  notInc i = notElem (prt i) $ map fileBody fs
  notIns i = notElem (prt i) $ map fileBody fs
  fts = readFiles st

pathListOpts :: Options -> FileName -> IO [InitPath]
pathListOpts opts file = return $ maybe [file] pFilePaths $ getOptVal opts pathList

reverseModules (MGrammar ms) = MGrammar $ reverse ms

keepResModules :: Options -> SourceGrammar -> SourceGrammar
keepResModules opts gr = 
  if oElem retainOpers opts 
    then MGrammar $ reverse [(i,mi) | (i,mi@(ModMod m)) <- modules gr, isModRes m]
    else emptyMGrammar


-- | the environment
type CompileEnv = (Int,SourceGrammar, GFC.CanonGrammar)

emptyCompileEnv :: TimedCompileEnv
emptyCompileEnv = ((0,emptyMGrammar,emptyMGrammar),[])

extendCompileEnvInt ((_,MGrammar ss, MGrammar cs),fts) (k,sm,cm) ft = 
  return ((k,MGrammar (sm:ss), MGrammar (cm:cs)),ft++fts) --- reverse later

extendCompileEnv e@((k,_,_),_) (sm,cm) = extendCompileEnvInt e (k,sm,cm)

extendCompileEnvCanon ((k,s,c),fts) cgr ft = 
  return ((k,s, MGrammar (modules cgr ++ modules c)),ft++fts)

type TimedCompileEnv = (CompileEnv,[(FilePath,ModTime)])

compileOne :: Options -> TimedCompileEnv -> FullPath -> IOE TimedCompileEnv
compileOne opts env@((_,srcgr,_),_) file = do

  let putp = putPointE opts
  let putpp = putPointEsil opts
  let putpOpt v m act
       | oElem beVerbose opts =  putp v act
       | oElem beSilent opts  =  putpp v act
       | otherwise = ioeIO (putStrFlush m) >> act

  let gf   = fileSuffix file
  let path = justInitPath file
  let name = fileBody file
  let mos  = modules srcgr

  case gf of
    -- for multilingual canonical gf, just read the file and update environment
    "gfcm" -> do
       cgr <- putp ("+ reading" +++ file) $ getCanonGrammar file
       ft <- getReadTimes file
       extendCompileEnvCanon env cgr ft

    -- for canonical gf, read the file and update environment, also source env
    "gfc" -> do
       cm <- putp ("+ reading" +++ file) $ getCanonModule file
       sm <- ioeErr $ CG.canon2sourceModule cm
       ft <- getReadTimes file
       extendCompileEnv env (sm, cm) ft

    -- for compiled resource, parse and organize, then update environment
    "gfr" -> do
       sm0 <- putp ("| reading" +++ file) $ getSourceModule file
       sm <- {- putp "creating indirections" $ -} ioeErr $ extendModule mos sm0
---- experiment with not optimizing gfr 
----      sm:_  <- putp "  optimizing " $ ioeErr $ evalModule mos sm1
       let gfc = gfcFile name 
       cm  <- putp ("+ reading" +++ gfc) $ getCanonModule gfc
       ft  <- getReadTimes file
       extendCompileEnv env (sm,cm) ft

    -- for gf source, do full compilation
    _ -> do
       sm0 <- putpOpt ("- parsing" +++ file) ("- compiling" +++ file ++ "... ") $ getSourceModule file
       (k',sm)  <- makeSourceModule opts (fst env) sm0
       cm  <- putpp "  generating code... " $ generateModuleCode opts path sm
       ft <- getReadTimes file

       sm':_ <- case snd sm of
----         ModMod n | isModRes n -> putp "  optimizing " $ ioeErr $ evalModule mos sm
         _ -> return [sm]

       extendCompileEnvInt env (k',sm',cm) ft

-- | dispatch reused resource at early stage
makeSourceModule :: Options -> CompileEnv -> SourceModule -> IOE (Int,SourceModule)
makeSourceModule opts env@(k,gr,can) mo@(i,mi) = case mi of

  ModMod m -> case mtype m of
    MTReuse c -> do
      sm <- ioeErr $ makeReuse gr i (extend m) c
      let mo2 = (i, ModMod sm)
          mos = modules gr
      --- putp "  type checking reused" $ ioeErr $ showCheckModule mos mo2
      return $ (k,mo2)
{- ---- obsolete
    MTUnion ty imps -> do
      mo' <- ioeErr $ makeUnion gr i ty imps
      compileSourceModule opts env mo'
-}

    _ -> compileSourceModule opts env mo
  _ -> compileSourceModule opts env mo
 where
   putp = putPointE opts

compileSourceModule :: Options -> CompileEnv -> 
                       SourceModule -> IOE (Int,SourceModule)
compileSourceModule opts env@(k,gr,can) mo@(i,mi) = do

  let putp  = putPointE opts
      putpp = putPointEsil opts
      mos   = modules gr

  if (oElem showOld opts && oElem emitCode opts) 
    then do
      let (file,out) = (gfFile (prt i), prGrammar (MGrammar [mo]))
      putp ("  wrote file" +++ file) $ ioeIO $ writeFile file out
    else return ()

  mo1   <- ioeErr $ rebuildModule mos mo

  mo1b  <- ioeErr $ extendModule mos mo1

  case mo1b of
    (_,ModMod n) | not (isCompleteModule n) -> do
      return (k,mo1b)   -- refresh would fail, since not renamed
    _ -> do
      mo2:_ <- putpp "  renaming " $ ioeErr $ renameModule mos mo1b

      (mo3:_,warnings) <- putpp "  type checking" $ ioeErr $ showCheckModule mos mo2
      if null warnings then return () else putp warnings $ return ()

      (k',mo3r:_) <- ioeErr $ refreshModule (k,mos) mo3

      mo4 <- 
----        case snd mo1b of
----          ModMod n | isModCnc n -> 
        putpp "  optimizing " $ ioeErr $ optimizeModule opts mos mo3r
----        _ -> return [mo3r]
      return (k',mo4)
 where
   ----   prDebug mo = ioeIO $ putStrLn $ prGrammar $ MGrammar [mo] ---- debug
   prDebug mo = ioeIO $ print $ length $ lines $ prGrammar $ MGrammar [mo]

generateModuleCode :: Options -> InitPath -> SourceModule -> IOE GFC.CanonModule
generateModuleCode opts path minfo@(name,info) = do
  let pname = prefixPathName path (prt name)
  minfo0     <- ioeErr $ redModInfo minfo
  let oopts = addOptions opts (iOpts (flagsModule minfo))
      optim = maybe "share" id $ getOptVal oopts useOptimizer
  minfo1     <- return $ 
    case optim of
      "parametrize" -> shareModule paramOpt minfo0  -- parametrization and sharing
      "values"      -> shareModule valOpt minfo0    -- tables as courses-of-values
      "share"       -> shareModule shareOpt minfo0  -- sharing of branches
      "all"         -> shareModule allOpt minfo0    -- first parametrize then values
      "none"        -> minfo0                       -- no optimization
      _             -> shareModule shareOpt minfo0  -- sharing; default

  -- do common subexpression elimination if required by flag "subs"
  minfo' <- 
    if oElem elimSubs opts
      then ioeErr $ elimSubtermsMod minfo1
      else return minfo1

  -- for resource, also emit gfr. 
  --- Also for incomplete, to create timestamped gfc/gfr files
  case info of
    ModMod m | emitsGFR m && emit && nomulti -> do
      let rminfo = if isCompilable info then minfo 
                   else (name,emptyModInfo) 
      let (file,out) = (gfrFile pname, prGrammar (MGrammar [rminfo]))
      putp ("  wrote file" +++ file) $ ioeIO $ writeFile file out
    _ -> return ()
  (file,out) <- do
      code <- return $ MkGFC.prCanonModInfo minfo'
      return (gfcFile pname, code)
  if emit && nomulti ---- && isCompilable info 
     then putp  ("  wrote file" +++ file) $ ioeIO $ writeFile file out
     else putpp ("no need to save module" +++ prt name) $ return ()
  return minfo'
 where 
   putp  = putPointE opts
   putpp = putPointEsil opts

   emitsGFR m = isModRes m ---- && isCompilable info
     ---- isModRes m || (isModCnc m && mstatus m == MSIncomplete)
   isCompilable mi = case mi of
     ModMod m -> not $ isModCnc m && mstatus m == MSIncomplete 
     _ -> True
   nomulti = not $ oElem makeMulti opts
   emit  = oElem emitCode opts && not (oElem notEmitCode opts)

-- for old GF: sort into modules, write files, compile as usual

compileOld :: Options -> FilePath -> IOE GFC.CanonGrammar
compileOld opts file = do
  let putp = putPointE opts
  grammar1 <- putp ("- parsing old gf" +++ file) $ getOldGrammar opts file
  files <- mapM writeNewGF $ modules grammar1
  ((_,_,grammar),_) <- foldM (compileOne opts) emptyCompileEnv files
  return grammar

writeNewGF :: SourceModule -> IOE FilePath
writeNewGF m@(i,_) = do
  let file = gfFile $ prt i
  ioeIO $ writeFile file $ prGrammar (MGrammar [m])
  ioeIO $ putStrLn $ "wrote file" +++ file
  return file

--- this function duplicates a lot of code from compileModule.
--- It does not really belong here either.
-- It selects those .gfe files that a grammar depends on and that
-- are younger than corresponding gf

getGFEFiles :: Options -> FilePath -> IO [FilePath]
getGFEFiles opts1 file = useIOE [] $ do
  opts0 <- ioeIO $ getOptionsFromFile file
  let useFileOpt = maybe False (const True) $ getOptVal opts0 pathList
  let useLineOpt = maybe False (const True) $ getOptVal opts1 pathList
  let opts = addOptions opts1 opts0 
  let fpath = justInitPath file
  ps0 <- ioeIO $ pathListOpts opts fpath

  let ps1 = if (useFileOpt && not useLineOpt) 
              then (map (prefixPathName fpath) ps0)
              else ps0
  ps <- ioeIO $ extendPathEnv gfLibraryPath gfGrammarPathVar ps1
  let file' = if useFileOpt then justFileName file else file -- to find file itself
  files <- getAllFiles opts ps [] file'
  efiles <- ioeIO $ filterM doesFileExist [suffixFile "gfe" (unsuffixFile f) | f <- files]
  es <- ioeIO $ mapM (uncurry selectLater) [(f, init f) | f <- efiles] -- init gfe == gf
  return $ filter ((=='e') . last) es