--
-- Haddock - A Haskell Documentation Tool
--
-- (c) Simon Marlow 2003
--


module Haddock.InterfaceFile (
  InterfaceFile(..),
  readInterfaceFile,
  writeInterfaceFile
) where


import Haddock.DocName ()
import Haddock.Types
import Haddock.Exception

import Data.List
import Data.Word
import Data.Array
import Data.IORef
import qualified Data.Map as Map
import System.IO
import Control.Monad

import GHC hiding (NoLink)
import SrcLoc   (noSrcSpan) -- tmp, GHC now exports this
import Binary
import Name
import UniqSupply
import UniqFM
import IfaceEnv
import Module
import Packages
import HscTypes
import FastMutInt
import InstEnv
import HsDoc
import FastString
import Unique


data InterfaceFile = InterfaceFile {
  ifLinkEnv         :: LinkEnv,
  ifInstalledIfaces :: [InstalledInterface]
} 


binaryInterfaceMagic :: Word32
binaryInterfaceMagic = 0xD0Cface


-- Since datatypes in GHC might change between patchlevel versions,
-- and because we store GHC datatypes in our interface files,
-- we need to make sure we version our interface files accordingly.
--
-- Instead of adding one, we add three to all version numbers
-- when one of our own (stored) datatypes is changed. 
binaryInterfaceVersion :: Word16
#if __GLASGOW_HASKELL__ == 608 && __GHC_PATCHLEVEL__ == 2
binaryInterfaceVersion = 2
#endif
#if __GLASGOW_HASKELL__ == 608 && __GHC_PATCHLEVEL__ == 3
binaryInterfaceVersion = 3
#endif
#if __GLASGOW_HASKELL__ >= 609
binaryInterfaceVersion = 4
#endif


initBinMemSize :: Int
initBinMemSize = 1024*1024


writeInterfaceFile :: FilePath -> InterfaceFile -> IO ()
writeInterfaceFile filename iface = do 
  bh <- openBinMem initBinMemSize
  put_ bh binaryInterfaceMagic
  put_ bh binaryInterfaceVersion

  -- remember where the dictionary pointer will go
  dict_p_p <- tellBin bh
  put_ bh dict_p_p	

  -- remember where the symbol table pointer will go
  symtab_p_p <- tellBin bh
  put_ bh symtab_p_p

  -- Make some intial state
#if __GLASGOW_HASKELL__ >= 609
  symtab_next <- newFastMutInt
  writeFastMutInt symtab_next 0
  symtab_map <- newIORef emptyUFM
  let bin_symtab = BinSymbolTable {
                      bin_symtab_next = symtab_next,
                      bin_symtab_map  = symtab_map }
  dict_next_ref <- newFastMutInt
  writeFastMutInt dict_next_ref 0
  dict_map_ref <- newIORef emptyUFM
  let bin_dict = BinDictionary {
                      bin_dict_next = dict_next_ref,
                      bin_dict_map  = dict_map_ref }
  ud <- newWriteState (putName bin_symtab) (putFastString bin_dict)
#else
  ud <- newWriteState
#endif

  -- put the main thing
  bh <- return $ setUserData bh ud
  put_ bh iface

  -- write the symtab pointer at the fornt of the file
  symtab_p <- tellBin bh
  putAt bh symtab_p_p symtab_p
  seekBin bh symtab_p		

  -- write the symbol table itself
#if __GLASGOW_HASKELL__ >= 609
  symtab_next <- readFastMutInt symtab_next
  symtab_map  <- readIORef symtab_map
#else
  symtab_next <- readFastMutInt (ud_symtab_next ud)
  symtab_map  <- readIORef (ud_symtab_map ud)
#endif
  putSymbolTable bh symtab_next symtab_map

  -- write the dictionary pointer at the fornt of the file
  dict_p <- tellBin bh
  putAt bh dict_p_p dict_p
  seekBin bh dict_p

  -- write the dictionary itself
#if __GLASGOW_HASKELL__ >= 609
  dict_next <- readFastMutInt dict_next_ref
  dict_map  <- readIORef dict_map_ref
#else
  dict_next <- readFastMutInt (ud_dict_next ud)
  dict_map  <- readIORef (ud_dict_map ud)
#endif
  putDictionary bh dict_next dict_map

  -- and send the result to the file
  writeBinMem bh filename
  return ()


-- | Read a Haddock (@.haddock@) interface file. Return either an 
-- 'InterfaceFile' or an error message. If given a GHC 'Session', the function
-- registers all read names in the name cache of the session.
readInterfaceFile :: Maybe Session -> FilePath -> IO (Either String InterfaceFile)
readInterfaceFile mbSession filename = do
  bh <- readBinMem filename

  magic   <- get bh
  version <- get bh

  case () of
    _ | magic /= binaryInterfaceMagic -> return . Left $
      "Magic number mismatch: couldn't load interface file: " ++ filename
      | version /= binaryInterfaceVersion -> return . Left $
      "Interface file is of wrong version: " ++ filename
      | otherwise -> do

      -- get the dictionary
      dict_p <- get bh
      data_p <- tellBin bh		
      seekBin bh dict_p
      dict <- getDictionary bh
      seekBin bh data_p		

      -- initialise the user-data field of bh
      ud <- newReadState dict
      bh <- return (setUserData bh ud)

      -- get the name cache from ghc if we have a ghc session,
      -- otherwise create a new one
      (theNC, mbRef) <- case mbSession of
        Just session -> do
          ref <- withSession session (return . hsc_NC)
          nc <- readIORef ref
          return (nc, Just ref)
        Nothing -> do
          -- construct an empty name cache
          u  <- mkSplitUniqSupply 'a' -- ??
          return (initNameCache u [], Nothing)

      -- get the symbol table
      symtab_p <- get bh
      data_p   <- tellBin bh
      seekBin bh symtab_p
      (nc', symtab) <- getSymbolTable bh theNC
      seekBin bh data_p

      -- write back the new name cache if we have a ghc session
      case mbRef of
        Just ref -> writeIORef ref nc'
        Nothing  -> return ()

      -- set the symbol table
      let ud = getUserData bh
      bh <- return $! setUserData bh ud{ud_symtab = symtab}

      -- load the actual data
      iface <- get bh
      return (Right iface)


-------------------------------------------------------------------------------
-- Symbol table
-------------------------------------------------------------------------------


#if __GLASGOW_HASKELL__ >= 609
putName :: BinSymbolTable -> BinHandle -> Name -> IO ()
putName BinSymbolTable{
            bin_symtab_map = symtab_map_ref,
            bin_symtab_next = symtab_next }    bh name
  = do
    symtab_map <- readIORef symtab_map_ref
    case lookupUFM symtab_map name of
      Just (off,_) -> put_ bh off
      Nothing -> do
         off <- readFastMutInt symtab_next
         writeFastMutInt symtab_next (off+1)
         writeIORef symtab_map_ref
             $! addToUFM symtab_map name (off,name)
         put_ bh off


data BinSymbolTable = BinSymbolTable {
        bin_symtab_next :: !FastMutInt, -- The next index to use
        bin_symtab_map  :: !(IORef (UniqFM (Int,Name)))
                                -- indexed by Name
  }


putFastString :: BinDictionary -> BinHandle -> FastString -> IO ()
putFastString BinDictionary { bin_dict_next = j_r,
                              bin_dict_map  = out_r}  bh f
  = do
    out <- readIORef out_r
    let uniq = getUnique f
    case lookupUFM out uniq of
        Just (j, _)  -> put_ bh j
        Nothing -> do
           j <- readFastMutInt j_r
           put_ bh j
           writeFastMutInt j_r (j + 1)
           writeIORef out_r $! addToUFM out uniq (j, f)


data BinDictionary = BinDictionary {
        bin_dict_next :: !FastMutInt, -- The next index to use
        bin_dict_map  :: !(IORef (UniqFM (Int,FastString)))
                                -- indexed by FastString
  }
#endif


putSymbolTable :: BinHandle -> Int -> UniqFM (Int,Name) -> IO ()
putSymbolTable bh next_off symtab = do
  put_ bh next_off
  let names = elems (array (0,next_off-1) (eltsUFM symtab))
  mapM_ (\n -> serialiseName bh n symtab) names

getSymbolTable :: BinHandle -> NameCache -> IO (NameCache, Array Int Name)
getSymbolTable bh namecache = do
  sz <- get bh
  od_names <- sequence (replicate sz (get bh))
  let 
        arr = listArray (0,sz-1) names
        (namecache', names) =    
                mapAccumR (fromOnDiskName arr) namecache od_names
  --
  return (namecache', arr)

type OnDiskName = (PackageId, ModuleName, OccName)

fromOnDiskName
   :: Array Int Name
   -> NameCache
   -> OnDiskName
   -> (NameCache, Name)
fromOnDiskName arr nc (pid, mod_name, occ) =
  let 
        mod   = mkModule pid mod_name
        cache = nsNames nc
  in
  case lookupOrigNameCache cache  mod occ of
     Just name -> (nc, name)
     Nothing   -> 
        let 
                us        = nsUniqs nc
                uniq      = uniqFromSupply us
                name      = mkExternalName uniq mod occ noSrcSpan
                new_cache = extendNameCache cache mod occ name
        in        
        case splitUniqSupply us of { (us',_) -> 
        ( nc{ nsUniqs = us', nsNames = new_cache }, name )
        }

serialiseName :: BinHandle -> Name -> UniqFM (Int,Name) -> IO ()
serialiseName bh name symtab = do
  let mod = nameModule name
  put_ bh (modulePackageId mod, moduleName mod, nameOccName name)


-------------------------------------------------------------------------------
-- GhcBinary instances
-------------------------------------------------------------------------------


instance Binary InterfaceFile where
  put_ bh (InterfaceFile env ifaces) = do
    put_ bh (Map.toList env)
    put_ bh ifaces

  get bh = do
    env    <- get bh
    ifaces <- get bh
    return (InterfaceFile (Map.fromList env) ifaces)


instance Binary InstalledInterface where
  put_ bh (InstalledInterface mod info docMap exps visExps) = do
    put_ bh mod
    put_ bh info
    put_ bh (Map.toList docMap)
    put_ bh exps
    put_ bh visExps

  get bh = do
    mod     <- get bh
    info    <- get bh
    docMap  <- get bh
    exps    <- get bh
    visExps <- get bh
    return (InstalledInterface mod info (Map.fromList docMap) exps visExps)


instance Binary DocOption where
    put_ bh OptHide = do
            putByte bh 0
    put_ bh OptPrune = do
            putByte bh 1
    put_ bh OptIgnoreExports = do
            putByte bh 2
    put_ bh OptNotHome = do
            putByte bh 3
    get bh = do
            h <- getByte bh
            case h of
              0 -> do
                    return OptHide
              1 -> do
                    return OptPrune
              2 -> do
                    return OptIgnoreExports
              3 -> do
                    return OptNotHome
              _ -> fail "invalid binary data found"


{-* Generated by DrIFT : Look, but Don't Touch. *-}
instance (Binary id) => Binary (HsDoc id) where
    put_ bh DocEmpty = do
            putByte bh 0
    put_ bh (DocAppend aa ab) = do
            putByte bh 1
            put_ bh aa
            put_ bh ab
    put_ bh (DocString ac) = do
            putByte bh 2
            put_ bh ac
    put_ bh (DocParagraph ad) = do
            putByte bh 3
            put_ bh ad
    put_ bh (DocIdentifier ae) = do
            putByte bh 4
            put_ bh ae
    put_ bh (DocModule af) = do
            putByte bh 5
            put_ bh af
    put_ bh (DocEmphasis ag) = do
            putByte bh 6
            put_ bh ag
    put_ bh (DocMonospaced ah) = do
            putByte bh 7
            put_ bh ah
    put_ bh (DocUnorderedList ai) = do
            putByte bh 8
            put_ bh ai
    put_ bh (DocOrderedList aj) = do
            putByte bh 9
            put_ bh aj
    put_ bh (DocDefList ak) = do
            putByte bh 10
            put_ bh ak
    put_ bh (DocCodeBlock al) = do
            putByte bh 11
            put_ bh al
    put_ bh (DocURL am) = do
            putByte bh 12
            put_ bh am
    put_ bh (DocAName an) = do
            putByte bh 13
            put_ bh an
    get bh = do
            h <- getByte bh
            case h of
              0 -> do
                    return DocEmpty
              1 -> do
                    aa <- get bh
                    ab <- get bh
                    return (DocAppend aa ab)
              2 -> do
                    ac <- get bh
                    return (DocString ac)
              3 -> do
                    ad <- get bh
                    return (DocParagraph ad)
              4 -> do
                    ae <- get bh
                    return (DocIdentifier ae)
              5 -> do
                    af <- get bh
                    return (DocModule af)
              6 -> do
                    ag <- get bh
                    return (DocEmphasis ag)
              7 -> do
                    ah <- get bh
                    return (DocMonospaced ah)
              8 -> do
                    ai <- get bh
                    return (DocUnorderedList ai)
              9 -> do
                    aj <- get bh
                    return (DocOrderedList aj)
              10 -> do
                    ak <- get bh
                    return (DocDefList ak)
              11 -> do
                    al <- get bh
                    return (DocCodeBlock al)
              12 -> do
                    am <- get bh
                    return (DocURL am)
              13 -> do
                    an <- get bh
                    return (DocAName an)
              _ -> fail "invalid binary data found"


instance Binary name => Binary (HaddockModInfo name) where
  put_ bh hmi = do
    put_ bh (hmi_description hmi)
    put_ bh (hmi_portability hmi)
    put_ bh (hmi_stability   hmi)
    put_ bh (hmi_maintainer  hmi)
  
  get bh = do
    descr <- get bh
    porta <- get bh
    stabi <- get bh
    maint <- get bh
    return (HaddockModInfo descr porta stabi maint)