content: -----------------------------------------------------------------------------
  -- |
  -- Module      :  Distribution.Simple.NHC
  -- Copyright   :  Isaac Jones 2003-2006
  --                Duncan Coutts 2009
  --
  -- Maintainer  :  cabal-devel@haskell.org
  -- Portability :  portable
  --
  -- This module contains most of the NHC-specific code for configuring, building
  -- and installing packages.
  
  {- Copyright (c) 2003-2005, Isaac Jones
  All rights reserved.
  
  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are
  met:
  
      * Redistributions of source code must retain the above copyright
        notice, this list of conditions and the following disclaimer.
  
      * Redistributions in binary form must reproduce the above
        copyright notice, this list of conditions and the following
        disclaimer in the documentation and/or other materials provided
        with the distribution.
  
      * Neither the name of Isaac Jones nor the names of other
        contributors may be used to endorse or promote products derived
        from this software without specific prior written permission.
  
  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -}
  
  module Distribution.Simple.NHC (
      configure,
      getInstalledPackages,
      buildLib,
      buildExe,
      installLib,
      installExe,
    ) where
  
  import Distribution.Package
           ( PackageName, PackageIdentifier(..), InstalledPackageId(..)
           , packageId, packageName )
  import Distribution.InstalledPackageInfo
           ( InstalledPackageInfo
           , InstalledPackageInfo_( InstalledPackageInfo, installedPackageId
                                  , sourcePackageId )
           , emptyInstalledPackageInfo, parseInstalledPackageInfo )
  import Distribution.PackageDescription
          ( PackageDescription(..), BuildInfo(..), Library(..), Executable(..)
          , hcOptions, usedExtensions )
  import Distribution.ModuleName (ModuleName)
  import qualified Distribution.ModuleName as ModuleName
  import Distribution.Simple.LocalBuildInfo
          ( LocalBuildInfo(..), ComponentLocalBuildInfo(..) )
  import Distribution.Simple.BuildPaths
          ( mkLibName, objExtension, exeExtension )
  import Distribution.Simple.Compiler
           ( CompilerFlavor(..), CompilerId(..), Compiler(..)
           , Flag, languageToFlags, extensionsToFlags
           , PackageDB(..), PackageDBStack )
  import qualified Distribution.Simple.PackageIndex as PackageIndex
  import Distribution.Simple.PackageIndex (PackageIndex)
  import Language.Haskell.Extension
           ( Language(Haskell98), Extension(..), KnownExtension(..) )
  import Distribution.Simple.Program
           ( ProgramConfiguration, userMaybeSpecifyPath, programPath
           , requireProgram, requireProgramVersion, lookupProgram
           , nhcProgram, hmakeProgram, ldProgram, arProgram
           , rawSystemProgramConf )
  import Distribution.Simple.Utils
          ( die, info, findFileWithExtension, findModuleFiles
          , installOrdinaryFile, installExecutableFile, installOrdinaryFiles
          , createDirectoryIfMissingVerbose, withUTF8FileContents )
  import Distribution.Version
          ( Version(..), orLaterVersion )
  import Distribution.Verbosity
  import Distribution.Text
           ( display, simpleParse )
  import Distribution.ParseUtils
           ( ParseResult(..) )
  
  import System.FilePath
          ( (</>), (<.>), normalise, takeDirectory, dropExtension )
  import System.Directory
           ( doesFileExist, doesDirectoryExist, getDirectoryContents
           , removeFile, getHomeDirectory )
  
  import Data.Char ( toLower )
  import Data.List ( nub )
  import Data.Maybe    ( catMaybes )
  import Data.Monoid   ( Monoid(..) )
  import Control.Monad ( when, unless )
  import Distribution.Compat.Exception
  
  -- -----------------------------------------------------------------------------
  -- Configuring
  
  configure :: Verbosity -> Maybe FilePath -> Maybe FilePath
            -> ProgramConfiguration -> IO (Compiler, ProgramConfiguration)
  configure verbosity hcPath _hcPkgPath conf = do
  
    (_nhcProg, nhcVersion, conf') <-
      requireProgramVersion verbosity nhcProgram
        (orLaterVersion (Version [1,20] []))
        (userMaybeSpecifyPath "nhc98" hcPath conf)
  
    (_hmakeProg, _hmakeVersion, conf'') <-
      requireProgramVersion verbosity hmakeProgram
       (orLaterVersion (Version [3,13] [])) conf'
    (_ldProg, conf''')   <- requireProgram verbosity ldProgram conf''
    (_arProg, conf'''')  <- requireProgram verbosity arProgram conf'''
  
    --TODO: put this stuff in a monad so we can say just:
    -- requireProgram hmakeProgram (orLaterVersion (Version [3,13] []))
    -- requireProgram ldProgram anyVersion
    -- requireProgram ldPrograrProgramam anyVersion
    -- unless (null (cSources bi)) $ requireProgram ccProgram anyVersion
  
    let comp = Compiler {
          compilerId         = CompilerId NHC nhcVersion,
          compilerLanguages  = nhcLanguages,
          compilerExtensions     = nhcLanguageExtensions
        }
    return (comp, conf'''')
  
  nhcLanguages :: [(Language, Flag)]
  nhcLanguages = [(Haskell98, "-98")]
  
  -- | The flags for the supported extensions
  nhcLanguageExtensions :: [(Extension, Flag)]
  nhcLanguageExtensions =
      -- TODO: pattern guards in 1.20
       -- NHC doesn't enforce the monomorphism restriction at all.
       -- Technically it therefore doesn't support MonomorphismRestriction,
       -- but that would mean it doesn't support Haskell98, so we pretend
       -- that it does.
      [(EnableExtension  MonomorphismRestriction,   "")
      ,(DisableExtension MonomorphismRestriction,   "")
       -- Similarly, I assume the FFI is always on
      ,(EnableExtension  ForeignFunctionInterface,  "")
      ,(DisableExtension ForeignFunctionInterface,  "")
       -- Similarly, I assume existential quantification is always on
      ,(EnableExtension  ExistentialQuantification, "")
      ,(DisableExtension ExistentialQuantification, "")
       -- Similarly, I assume empty data decls is always on
      ,(EnableExtension  EmptyDataDecls,            "")
      ,(DisableExtension EmptyDataDecls,            "")
      ,(EnableExtension  NamedFieldPuns,            "-puns")
      ,(DisableExtension NamedFieldPuns,            "-nopuns")
       -- CPP can't actually be turned off, but we pretend that it can
      ,(EnableExtension  CPP,                       "-cpp")
      ,(DisableExtension CPP,                       "")
      ]
  
  getInstalledPackages :: Verbosity -> PackageDBStack -> ProgramConfiguration
                       -> IO PackageIndex
  getInstalledPackages verbosity packagedbs conf = do
    homedir      <- getHomeDirectory
    (nhcProg, _) <- requireProgram verbosity nhcProgram conf
    let bindir = takeDirectory (programPath nhcProg)
        incdir = takeDirectory bindir </> "include" </> "nhc98"
        dbdirs = nub (concatMap (packageDbPaths homedir incdir) packagedbs)
    indexes  <- mapM getIndividualDBPackages dbdirs
    return $! mconcat indexes
  
    where
      getIndividualDBPackages :: FilePath -> IO PackageIndex
      getIndividualDBPackages dbdir = do
        pkgdirs <- getPackageDbDirs dbdir
        pkgs    <- sequence [ getInstalledPackage pkgname pkgdir
                            | (pkgname, pkgdir) <- pkgdirs ]
        let pkgs' = map setInstalledPackageId (catMaybes pkgs)
        return (PackageIndex.fromList pkgs')
  
  packageDbPaths :: FilePath -> FilePath -> PackageDB -> [FilePath]
  packageDbPaths _home incdir db = case db of
    GlobalPackageDB        -> [ incdir </> "packages" ]
    UserPackageDB          -> [] --TODO any standard per-user db?
    SpecificPackageDB path -> [ path ]
  
  getPackageDbDirs :: FilePath -> IO [(PackageName, FilePath)]
  getPackageDbDirs dbdir = do
    dbexists <- doesDirectoryExist dbdir
    if not dbexists
      then return []
      else do
        entries  <- getDirectoryContents dbdir
        pkgdirs  <- sequence
          [ do pkgdirExists <- doesDirectoryExist pkgdir
               return (pkgname, pkgdir, pkgdirExists)
          | (entry, Just pkgname) <- [ (entry, simpleParse entry)
                                     | entry <- entries ]
          , let pkgdir = dbdir </> entry ]
        return [ (pkgname, pkgdir) | (pkgname, pkgdir, True) <- pkgdirs ]
  
  getInstalledPackage :: PackageName -> FilePath -> IO (Maybe InstalledPackageInfo)
  getInstalledPackage pkgname pkgdir = do
    let pkgconfFile = pkgdir </> "package.conf"
    pkgconfExists <- doesFileExist pkgconfFile
  
    let cabalFile = pkgdir <.> "cabal"
    cabalExists <- doesFileExist cabalFile
  
    case () of
      _ | pkgconfExists -> getFullInstalledPackageInfo pkgname pkgconfFile
        | cabalExists   -> getPhonyInstalledPackageInfo pkgname cabalFile
        | otherwise     -> return Nothing
  
  getFullInstalledPackageInfo :: PackageName -> FilePath
                              -> IO (Maybe InstalledPackageInfo)
  getFullInstalledPackageInfo pkgname pkgconfFile =
    withUTF8FileContents pkgconfFile $ \contents ->
      case parseInstalledPackageInfo contents of
        ParseOk _ pkginfo | packageName pkginfo == pkgname
                          -> return (Just pkginfo)
        _                 -> return Nothing
  
  -- | This is a backup option for existing versions of nhc98 which do not supply
  -- proper installed package info files for the bundled libs. Instead we look
  -- for the .cabal file and extract the package version from that.
  -- We don't know any other details for such packages, in particular we pretend
  -- that they have no dependencies.
  --
  getPhonyInstalledPackageInfo :: PackageName -> FilePath
                               -> IO (Maybe InstalledPackageInfo)
  getPhonyInstalledPackageInfo pkgname pathsModule = do
    content <- readFile pathsModule
    case extractVersion content of
      Nothing      -> return Nothing
      Just version -> return (Just pkginfo)
        where
          pkgid   = PackageIdentifier pkgname version
          pkginfo = emptyInstalledPackageInfo { sourcePackageId = pkgid }
    where
      -- search through the .cabal file, looking for a line like:
      --
      -- > version: 2.0
      --
      extractVersion :: String -> Maybe Version
      extractVersion content =
        case catMaybes (map extractVersionLine (lines content)) of
          [version] -> Just version
          _         -> Nothing
      extractVersionLine :: String -> Maybe Version
      extractVersionLine line =
        case words line of
          [versionTag, ":", versionStr]
            | map toLower versionTag == "version"  -> simpleParse versionStr
          [versionTag,      versionStr]
            | map toLower versionTag == "version:" -> simpleParse versionStr
          _                                        -> Nothing
  
  -- Older installed package info files did not have the installedPackageId
  -- field, so if it is missing then we fill it as the source package ID.
  setInstalledPackageId :: InstalledPackageInfo -> InstalledPackageInfo
  setInstalledPackageId pkginfo@InstalledPackageInfo {
                          installedPackageId = InstalledPackageId "",
                          sourcePackageId    = pkgid
                        }
                      = pkginfo {
                          --TODO use a proper named function for the conversion
                          -- from source package id to installed package id
                          installedPackageId = InstalledPackageId (display pkgid)
                        }
  setInstalledPackageId pkginfo = pkginfo
  
  -- -----------------------------------------------------------------------------
  -- Building
  
  -- |FIX: For now, the target must contain a main module.  Not used
  -- ATM. Re-add later.
  buildLib :: Verbosity -> PackageDescription -> LocalBuildInfo
                        -> Library            -> ComponentLocalBuildInfo -> IO ()
  buildLib verbosity pkg_descr lbi lib clbi = do
    let conf = withPrograms lbi
        Just nhcProg = lookupProgram nhcProgram conf
    let bi = libBuildInfo lib
        modules = exposedModules lib ++ otherModules bi
        -- Unsupported extensions have already been checked by configure
        languageFlags = languageToFlags (compiler lbi) (defaultLanguage bi)
                     ++ extensionsToFlags (compiler lbi) (usedExtensions bi)
    inFiles <- getModulePaths lbi bi modules
    let targetDir = buildDir lbi
        srcDirs  = nub (map takeDirectory inFiles)
        destDirs = map (targetDir </>) srcDirs
    mapM_ (createDirectoryIfMissingVerbose verbosity True) destDirs
    rawSystemProgramConf verbosity hmakeProgram conf $
         ["-hc=" ++ programPath nhcProg]
      ++ nhcVerbosityOptions verbosity
      ++ ["-d", targetDir, "-hidir", targetDir]
      ++ maybe [] (hcOptions NHC . libBuildInfo)
                             (library pkg_descr)
      ++ languageFlags
      ++ concat [ ["-package", display (packageName pkgid) ]
                | (_, pkgid) <- componentPackageDeps clbi ]
      ++ inFiles
  {-
    -- build any C sources
    unless (null (cSources bi)) $ do
       info verbosity "Building C Sources..."
       let commonCcArgs = (if verbosity >= deafening then ["-v"] else [])
                       ++ ["-I" ++ dir | dir <- includeDirs bi]
                       ++ [opt | opt <- ccOptions bi]
                       ++ (if withOptimization lbi then ["-O2"] else [])
       flip mapM_ (cSources bi) $ \cfile -> do
         let ofile = targetDir </> cfile `replaceExtension` objExtension
         createDirectoryIfMissingVerbose verbosity True (takeDirectory ofile)
         rawSystemProgramConf verbosity hmakeProgram conf
           (commonCcArgs ++ ["-c", cfile, "-o", ofile])
  -}
    -- link:
    info verbosity "Linking..."
    let --cObjs = [ targetDir </> cFile `replaceExtension` objExtension
        --        | cFile <- cSources bi ]
        libFilePath = targetDir </> mkLibName (packageId pkg_descr)
        hObjs = [ targetDir </> ModuleName.toFilePath m <.> objExtension
                | m <- modules ]
  
    unless (null hObjs {-&& null cObjs-}) $ do
      -- first remove library if it exists
      removeFile libFilePath `catchIO` \_ -> return ()
  
      let arVerbosity | verbosity >= deafening = "v"
                      | verbosity >= normal = ""
                      | otherwise = "c"
  
      rawSystemProgramConf verbosity arProgram (withPrograms lbi) $
           ["q"++ arVerbosity, libFilePath]
        ++ hObjs
  --    ++ cObjs
  
  -- | Building an executable for NHC.
  buildExe :: Verbosity -> PackageDescription -> LocalBuildInfo
                        -> Executable         -> ComponentLocalBuildInfo -> IO ()
  buildExe verbosity pkg_descr lbi exe clbi = do
    let conf = withPrograms lbi
        Just nhcProg = lookupProgram nhcProgram conf
    when (dropExtension (modulePath exe) /= exeName exe) $
      die $ "hmake does not support exe names that do not match the name of "
         ++ "the 'main-is' file. You will have to rename your executable to "
         ++ show (dropExtension (modulePath exe))
    let bi = buildInfo exe
        modules = otherModules bi
        -- Unsupported extensions have already been checked by configure
        languageFlags = languageToFlags (compiler lbi) (defaultLanguage bi)
                     ++ extensionsToFlags (compiler lbi) (usedExtensions bi)
    inFiles <- getModulePaths lbi bi modules
    let targetDir = buildDir lbi </> exeName exe
        exeDir    = targetDir </> (exeName exe ++ "-tmp")
        srcDirs   = nub (map takeDirectory (modulePath exe : inFiles))
        destDirs  = map (exeDir </>) srcDirs
    mapM_ (createDirectoryIfMissingVerbose verbosity True) destDirs
    rawSystemProgramConf verbosity hmakeProgram conf $
         ["-hc=" ++ programPath nhcProg]
      ++ nhcVerbosityOptions verbosity
      ++ ["-d", targetDir, "-hidir", targetDir]
      ++ maybe [] (hcOptions NHC . libBuildInfo)
                             (library pkg_descr)
      ++ languageFlags
      ++ concat [ ["-package", display (packageName pkgid) ]
                | (_, pkgid) <- componentPackageDeps clbi ]
      ++ inFiles
      ++ [exeName exe]
  
  nhcVerbosityOptions :: Verbosity -> [String]
  nhcVerbosityOptions verbosity
       | verbosity >= deafening = ["-v"]
       | verbosity >= normal    = []
       | otherwise              = ["-q"]
  
  --TODO: where to put this? it's duplicated in .Simple too
  getModulePaths :: LocalBuildInfo -> BuildInfo -> [ModuleName] -> IO [FilePath]
  getModulePaths lbi bi modules = sequence
     [ findFileWithExtension ["hs", "lhs"] (buildDir lbi : hsSourceDirs bi)
         (ModuleName.toFilePath module_) >>= maybe (notFound module_) (return . normalise)
     | module_ <- modules ]
     where notFound module_ = die $ "can't find source for module " ++ display module_
  
  -- -----------------------------------------------------------------------------
  -- Installing
  
  -- |Install executables for NHC.
  installExe :: Verbosity -- ^verbosity
             -> FilePath  -- ^install location
             -> FilePath  -- ^Build location
             -> (FilePath, FilePath)  -- ^Executable (prefix,suffix)
             -> Executable
             -> IO ()
  installExe verbosity pref buildPref (progprefix,progsuffix) exe
      = do createDirectoryIfMissingVerbose verbosity True pref
           let exeBaseName = exeName exe
               exeFileName = exeBaseName <.> exeExtension
               fixedExeFileName = (progprefix ++ exeBaseName ++ progsuffix) <.> exeExtension
           installExecutableFile verbosity
             (buildPref </> exeBaseName </> exeFileName)
             (pref </> fixedExeFileName)
  
  -- |Install for nhc98: .hi and .a files
  installLib    :: Verbosity -- ^verbosity
                -> FilePath  -- ^install location
                -> FilePath  -- ^Build location
                -> PackageIdentifier
                -> Library
                -> IO ()
  installLib verbosity pref buildPref pkgid lib
      = do let bi = libBuildInfo lib
               modules = exposedModules lib ++ otherModules bi
           findModuleFiles [buildPref] ["hi"] modules
             >>= installOrdinaryFiles verbosity pref
           let libName = mkLibName pkgid
           installOrdinaryFile verbosity (buildPref </> libName) (pref </> libName)
  