    {-# OPTIONS -cpp #-}
    -----------------------------------------------------------------------------
    -- |
    -- Module      :  Distribution.Simple.SrcDist
    -- Copyright   :  Simon Marlow 2004
    --
    -- Maintainer  :  Isaac Jones <ijones@syntaxpolice.org>
    -- Stability   :  alpha
    -- Portability :  portable
    --
    -- Implements the \"@.\/setup sdist@\" command, which creates a source
    -- distribution for this package.  That is, packs up the source code
    -- into a tarball.

    {- Copyright (c) 2003-2004, Simon Marlow
    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. -}

    -- NOTE: FIX: we don't have a great way of testing this module, since
    -- we can't easily look inside a tarball once its created.

    module Distribution.Simple.SrcDist (
    	 sdist
            ,createArchive
            ,prepareTree
            ,tarBallName
            ,copyFileTo
    #ifdef DEBUG
            ,hunitTests
    #endif
      )  where

    import Distribution.PackageDescription
    	(PackageDescription(..), BuildInfo(..), Executable(..), Library(..),
             withLib, withExe, setupMessage)
    import Distribution.Package (showPackageId, PackageIdentifier(pkgVersion))
    import Distribution.Version (Version(versionBranch), VersionRange(AnyVersion))
    import Distribution.Simple.Utils (createDirectoryIfMissingVerbose,
                                      smartCopySources, die, warn, notice,
                                      findPackageDesc, findFile, findFileWithExtension,
                                      copyFileVerbose)
    import Distribution.Simple.Setup (SDistFlags(..))
    import Distribution.Simple.PreProcess (PPSuffixHandler, ppSuffixes, preprocessSources)
    import Distribution.Simple.LocalBuildInfo ( LocalBuildInfo(..) )
    import Distribution.Simple.Program ( defaultProgramConfiguration, requireProgram,
                                  rawSystemProgram, tarProgram )

    #ifndef __NHC__
    import Control.Exception (finally)
    #endif
    import Control.Monad(when)
    import Data.Char (isSpace, toLower)
    import Data.List (isPrefixOf)
    import System.Time (getClockTime, toCalendarTime, CalendarTime(..))
    import Distribution.Compat.Directory (doesFileExist, doesDirectoryExist,
             getCurrentDirectory, removeDirectoryRecursive)
    import Distribution.Verbosity
    import System.FilePath ((</>), takeDirectory, isAbsolute, dropExtension)

    #ifdef DEBUG
    import Test.HUnit (Test)
    #endif

    #ifdef __NHC__
    finally :: IO a -> IO b -> IO a
    x `finally` y = do { a <- x; y; return a }
    #endif

    -- |Create a source distribution.
    sdist :: PackageDescription -- ^information from the tarball
          -> Maybe LocalBuildInfo -- ^Information from configure
          -> SDistFlags -- ^verbosity & snapshot
          -> FilePath -- ^build prefix (temp dir)
          -> FilePath -- ^TargetPrefix
          -> [PPSuffixHandler]  -- ^ extra preprocessors (includes suffixes)
          -> IO ()
    sdist pkg_descr_orig mb_lbi (SDistFlags snapshot verbosity) tmpDir targetPref pps = do
        time <- getClockTime
        ct <- toCalendarTime time
        let date = ctYear ct*10000 + (fromEnum (ctMonth ct) + 1)*100 + ctDay ct
        let pkg_descr
              | snapshot  = updatePackage (updatePkgVersion
                              (updateVersionBranch (++ [date]))) pkg_descr_orig
              | otherwise = pkg_descr_orig
        prepareTree pkg_descr verbosity mb_lbi snapshot tmpDir pps date
        createArchive pkg_descr verbosity mb_lbi tmpDir targetPref
        return ()
      where
        updatePackage f pd = pd { package = f (package pd) }
        updatePkgVersion f pkg = pkg { pkgVersion = f (pkgVersion pkg) }
        updateVersionBranch f v = v { versionBranch = f (versionBranch v) }

    -- |Prepare a directory tree of source files.
    prepareTree :: PackageDescription -- ^info from the cabal file
                -> Verbosity          -- ^verbosity
                -> Maybe LocalBuildInfo
                -> Bool               -- ^snapshot
                -> FilePath           -- ^source tree to populate
                -> [PPSuffixHandler]  -- ^extra preprocessors (includes suffixes)
                -> Int                -- ^date
                -> IO FilePath

    prepareTree pkg_descr verbosity mb_lbi snapshot tmpDir pps date = do
      setupMessage verbosity "Building source dist for" pkg_descr
      ex <- doesDirectoryExist tmpDir
      when ex (die $ "Source distribution already in place. please move: " ++ tmpDir)
      let targetDir = tmpDir </> (nameVersion pkg_descr)
      createDirectoryIfMissingVerbose verbosity True targetDir
      -- maybe move the library files into place
      withLib pkg_descr () $ \ l ->
        prepareDir verbosity targetDir pps (exposedModules l) (libBuildInfo l)
      -- move the executables into place
      withExe pkg_descr $ \ (Executable _ mainPath exeBi) -> do
        prepareDir verbosity targetDir pps [] exeBi
        srcMainFile <- do
          ppFile <- findFileWithExtension (ppSuffixes pps) (hsSourceDirs exeBi) (dropExtension mainPath)
          case ppFile of
            Nothing -> findFile (hsSourceDirs exeBi) mainPath
            Just pp -> return pp
        copyFileTo verbosity targetDir srcMainFile
      flip mapM_ (dataFiles pkg_descr) $ \ file -> do
        let dir = takeDirectory file
        createDirectoryIfMissingVerbose verbosity True (targetDir </> dir)
        copyFileVerbose verbosity file (targetDir </> file)

      when (not (null (licenseFile pkg_descr))) $
        copyFileTo verbosity targetDir (licenseFile pkg_descr)
      flip mapM_ (extraSrcFiles pkg_descr) $ \ fpath -> do
        copyFileTo verbosity targetDir fpath

      -- copy the install-include files
      withLib pkg_descr () $ \ l -> do
        let lbi = libBuildInfo l
            relincdirs = "." : filter (not.isAbsolute) (includeDirs lbi)
        incs <- mapM (findInc relincdirs) (installIncludes lbi)
        flip mapM_ incs $ \(_,fpath) ->
           copyFileTo verbosity targetDir fpath

      -- we have some preprocessors specified, try to generate those files
      when (not (null pps)) $
        case mb_lbi of
          Just lbi -> preprocessSources pkg_descr (lbi { buildDir = targetDir })
                                        True verbosity pps
          Nothing -> warn verbosity
              "Cannot run preprocessors.  Run 'configure' command first."

      -- setup isn't listed in the description file.
      hsExists <- doesFileExist "Setup.hs"
      lhsExists <- doesFileExist "Setup.lhs"
      if hsExists then copyFileTo verbosity targetDir "Setup.hs"
        else if lhsExists then copyFileTo verbosity targetDir "Setup.lhs"
        else writeFile (targetDir </> "Setup.hs") $ unlines [
                    "import Distribution.Simple",
                    "main = defaultMain"]
      -- the description file itself
      descFile <- getCurrentDirectory >>= findPackageDesc verbosity
      let targetDescFile = targetDir </> descFile
      -- We could just writePackageDescription targetDescFile pkg_descr,
      -- but that would lose comments and formatting.
      if snapshot then do
          contents <- readFile descFile
          writeFile targetDescFile $
              unlines $ map (appendVersion date) $ lines $ contents
        else copyFileVerbose verbosity descFile targetDescFile
      return targetDir

      where

        appendVersion :: Int -> String -> String
        appendVersion n line
          | "version:" `isPrefixOf` map toLower line =
                trimTrailingSpace line ++ "." ++ show n
          | otherwise = line

        trimTrailingSpace :: String -> String
        trimTrailingSpace = reverse . dropWhile isSpace . reverse

        findInc [] f = die ("can't find include file " ++ f)
        findInc (d:ds) f = do
          let path = (d </> f)
          b <- doesFileExist path
          if b then return (f,path) else findInc ds f

    -- |Create an archive from a tree of source files, and clean up the tree.
    createArchive :: PackageDescription   -- ^info from cabal file
                  -> Verbosity            -- ^verbosity
                  -> Maybe LocalBuildInfo -- ^info from configure
                  -> FilePath             -- ^source tree to archive
                  -> FilePath             -- ^name of archive to create
                  -> IO FilePath

    createArchive pkg_descr verbosity mb_lbi tmpDir targetPref = do
      let tarBallFilePath = targetPref </> tarBallName pkg_descr

      (tarProg, _) <- requireProgram verbosity tarProgram AnyVersion
                        (maybe defaultProgramConfiguration withPrograms mb_lbi)

       -- Hmm: I could well be skating on thinner ice here by using the -C option (=> GNU tar-specific?)
       -- [The prev. solution used pipes and sub-command sequences to set up the paths correctly,
       -- which is problematic in a Windows setting.]
      rawSystemProgram verbosity tarProg
               ["-C", tmpDir, "-czf", tarBallFilePath, nameVersion pkg_descr]
          -- XXX this should be done back where tmpDir is made, not here
          `finally` removeDirectoryRecursive tmpDir
      notice verbosity $ "Source tarball created: " ++ tarBallFilePath
      return tarBallFilePath

    -- |Move the sources into place based on buildInfo
    prepareDir :: Verbosity -- ^verbosity
               -> FilePath  -- ^TargetPrefix
               -> [PPSuffixHandler]  -- ^ extra preprocessors (includes suffixes)
               -> [String]  -- ^Exposed modules
               -> BuildInfo
               -> IO ()
    prepareDir verbosity inPref pps mods BuildInfo{hsSourceDirs=srcDirs, otherModules=mods', cSources=cfiles}
        = do let suff = ppSuffixes pps  ++ ["hs", "lhs"]
             smartCopySources verbosity srcDirs inPref (mods++mods') suff True True
             mapM_ (copyFileTo verbosity inPref) cfiles

    copyFileTo :: Verbosity -> FilePath -> FilePath -> IO ()
    copyFileTo verbosity dir file = do
      let targetFile = dir </> file
      createDirectoryIfMissingVerbose verbosity True (takeDirectory targetFile)
      copyFileVerbose verbosity file targetFile

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

    -- |The file name of the tarball
    tarBallName :: PackageDescription -> FilePath
    tarBallName p = (nameVersion p) ++ ".tar.gz"

    nameVersion :: PackageDescription -> String
    nameVersion = showPackageId . package

    -- ------------------------------------------------------------
    -- * Testing
    -- ------------------------------------------------------------

    #ifdef DEBUG
    hunitTests :: [Test]
    hunitTests = []
    #endif