content: -----------------------------------------------------------------------------
  -- |
  -- Module      :  Distribution.Simple.UHC
  -- Copyright   :  Andres Loeh 2009
  --
  -- Maintainer  :  cabal-devel@haskell.org
  -- Portability :  portable
  --
  -- This module contains most of the UHC-specific code for configuring, building
  -- and installing packages.
  --
  -- Thanks to the authors of the other implementation-specific files, in
  -- particular to Isaac Jones, Duncan Coutts and Henning Thielemann, for
  -- inspiration on how to design this module.
  
  {-
  Copyright (c) 2009, Andres Loeh
  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.UHC (
      configure, getInstalledPackages,
      buildLib, buildExe, installLib, registerPackage
    ) where
  
  import Control.Monad
  import Data.List
  import Distribution.Compat.ReadP
  import Distribution.InstalledPackageInfo
  import Distribution.Package
  import Distribution.PackageDescription
  import Distribution.Simple.BuildPaths
  import Distribution.Simple.Compiler as C
  import Distribution.Simple.LocalBuildInfo
  import Distribution.Simple.PackageIndex
  import Distribution.Simple.Program
  import Distribution.Simple.Utils
  import Distribution.Text
  import Distribution.Verbosity
  import Distribution.Version
  import Language.Haskell.Extension
  import System.Directory
  import System.FilePath
  import Distribution.System ( Platform )
  
  -- -----------------------------------------------------------------------------
  -- Configuring
  
  configure :: Verbosity -> Maybe FilePath -> Maybe FilePath
            -> ProgramConfiguration -> IO (Compiler, Maybe Platform, ProgramConfiguration)
  configure verbosity hcPath _hcPkgPath conf = do
  
    (_uhcProg, uhcVersion, conf') <-
      requireProgramVersion verbosity uhcProgram
      (orLaterVersion (Version [1,0,2] []))
      (userMaybeSpecifyPath "uhc" hcPath conf)
  
    let comp = Compiler {
                 compilerId         =  CompilerId UHC uhcVersion,
                 compilerLanguages  =  uhcLanguages,
                 compilerExtensions =  uhcLanguageExtensions
               }
        compPlatform = Nothing
    return (comp, compPlatform, conf')
  
  uhcLanguages :: [(Language, C.Flag)]
  uhcLanguages = [(Haskell98, "")]
  
  -- | The flags for the supported extensions.
  uhcLanguageExtensions :: [(Extension, C.Flag)]
  uhcLanguageExtensions =
      let doFlag (f, (enable, disable)) = [(EnableExtension  f, enable),
                                           (DisableExtension f, disable)]
          alwaysOn = ("", ""{- wrong -})
      in concatMap doFlag
      [(CPP,                          ("--cpp", ""{- wrong -})),
       (PolymorphicComponents,        alwaysOn),
       (ExistentialQuantification,    alwaysOn),
       (ForeignFunctionInterface,     alwaysOn),
       (UndecidableInstances,         alwaysOn),
       (MultiParamTypeClasses,        alwaysOn),
       (Rank2Types,                   alwaysOn),
       (PatternSignatures,            alwaysOn),
       (EmptyDataDecls,               alwaysOn),
       (ImplicitPrelude,              ("", "--no-prelude"{- wrong -})),
       (TypeOperators,                alwaysOn),
       (OverlappingInstances,         alwaysOn),
       (FlexibleInstances,            alwaysOn)]
  
  getInstalledPackages :: Verbosity -> Compiler -> PackageDBStack -> ProgramConfiguration
                       -> IO PackageIndex
  getInstalledPackages verbosity comp packagedbs conf = do
    let compilerid = compilerId comp
    systemPkgDir <- rawSystemProgramStdoutConf verbosity uhcProgram conf ["--meta-pkgdir-system"]
    userPkgDir   <- getUserPackageDir
    let pkgDirs    = nub (concatMap (packageDbPaths userPkgDir systemPkgDir) packagedbs)
    -- putStrLn $ "pkgdirs: " ++ show pkgDirs
    -- call to "lines" necessary, because pkgdir contains an extra newline at the end
    pkgs <- liftM (map addBuiltinVersions . concat) .
            mapM (\ d -> getDirectoryContents d >>= filterM (isPkgDir (display compilerid) d)) .
            concatMap lines $ pkgDirs
    -- putStrLn $ "pkgs: " ++ show pkgs
    let iPkgs =
          map mkInstalledPackageInfo $
          concatMap parsePackage $
          pkgs
    -- putStrLn $ "installed pkgs: " ++ show iPkgs
    return (fromList iPkgs)
  
  getUserPackageDir :: IO FilePath
  getUserPackageDir =
    do
      homeDir <- getHomeDirectory
      return $ homeDir </> ".cabal" </> "lib"  -- TODO: determine in some other way
  
  packageDbPaths :: FilePath -> FilePath -> PackageDB -> [FilePath]
  packageDbPaths user system db =
    case db of
      GlobalPackageDB         ->  [ system ]
      UserPackageDB           ->  [ user ]
      SpecificPackageDB path  ->  [ path ]
  
  -- | Hack to add version numbers to UHC-builtin packages. This should sooner or
  -- later be fixed on the UHC side.
  addBuiltinVersions :: String -> String
  {-
  addBuiltinVersions "uhcbase"  = "uhcbase-1.0"
  addBuiltinVersions "base"  = "base-3.0"
  addBuiltinVersions "array" = "array-0.2"
  -}
  addBuiltinVersions xs      = xs
  
  -- | Name of the installed package config file.
  installedPkgConfig :: String
  installedPkgConfig = "installed-pkg-config"
  
  -- | Check if a certain dir contains a valid package. Currently, we are
  -- looking only for the presence of an installed package configuration.
  -- TODO: Actually make use of the information provided in the file.
  isPkgDir :: String -> String -> String -> IO Bool
  isPkgDir _ _   ('.' : _)  = return False  -- ignore files starting with a .
  isPkgDir c dir xs         = do
                                let candidate = dir </> uhcPackageDir xs c
                                -- putStrLn $ "trying: " ++ candidate
                                doesFileExist (candidate </> installedPkgConfig)
  
  parsePackage :: String -> [PackageId]
  parsePackage x = map fst (filter (\ (_,y) -> null y) (readP_to_S parse x))
  
  -- | Create a trivial package info from a directory name.
  mkInstalledPackageInfo :: PackageId -> InstalledPackageInfo
  mkInstalledPackageInfo p = emptyInstalledPackageInfo
    { installedPackageId = InstalledPackageId (display p),
      sourcePackageId    = p }
  
  
  -- -----------------------------------------------------------------------------
  -- Building
  
  buildLib :: Verbosity -> PackageDescription -> LocalBuildInfo
                        -> Library            -> ComponentLocalBuildInfo -> IO ()
  buildLib verbosity pkg_descr lbi lib clbi = do
  
    systemPkgDir <- rawSystemProgramStdoutConf verbosity uhcProgram (withPrograms lbi) ["--meta-pkgdir-system"]
    userPkgDir   <- getUserPackageDir
    let runUhcProg = rawSystemProgramConf verbosity uhcProgram (withPrograms lbi)
    let uhcArgs =    -- set package name
                     ["--pkg-build=" ++ display (packageId pkg_descr)]
                     -- common flags lib/exe
                  ++ constructUHCCmdLine userPkgDir systemPkgDir
                                         lbi (libBuildInfo lib) clbi
                                         (buildDir lbi) verbosity
                     -- source files
                     -- suboptimal: UHC does not understand module names, so
                     -- we replace periods by path separators
                  ++ map (map (\ c -> if c == '.' then pathSeparator else c))
                         (map display (libModules lib))
  
    runUhcProg uhcArgs
    
    return ()
  
  buildExe :: Verbosity -> PackageDescription -> LocalBuildInfo
                        -> Executable         -> ComponentLocalBuildInfo -> IO ()
  buildExe verbosity _pkg_descr lbi exe clbi = do
    systemPkgDir <- rawSystemProgramStdoutConf verbosity uhcProgram (withPrograms lbi) ["--meta-pkgdir-system"]
    userPkgDir   <- getUserPackageDir
    let runUhcProg = rawSystemProgramConf verbosity uhcProgram (withPrograms lbi)
    let uhcArgs =    -- common flags lib/exe
                     constructUHCCmdLine userPkgDir systemPkgDir
                                         lbi (buildInfo exe) clbi
                                         (buildDir lbi) verbosity
                     -- output file
                  ++ ["--output", buildDir lbi </> exeName exe]
                     -- main source module
                  ++ [modulePath exe]
    runUhcProg uhcArgs
  
  constructUHCCmdLine :: FilePath -> FilePath
                      -> LocalBuildInfo -> BuildInfo -> ComponentLocalBuildInfo
                      -> FilePath -> Verbosity -> [String]
  constructUHCCmdLine user system lbi bi clbi odir verbosity =
       -- verbosity
       (if      verbosity >= deafening then ["-v4"]
        else if verbosity >= normal    then []
        else                                ["-v0"])
    ++ hcOptions UHC bi
       -- flags for language extensions
    ++ languageToFlags   (compiler lbi) (defaultLanguage bi)
    ++ extensionsToFlags (compiler lbi) (usedExtensions bi)
       -- packages
    ++ ["--hide-all-packages"]
    ++ uhcPackageDbOptions user system (withPackageDB lbi)
    ++ ["--package=uhcbase"]
    ++ ["--package=" ++ display (pkgName pkgid) | (_, pkgid) <- componentPackageDeps clbi ]
       -- search paths
    ++ ["-i" ++ odir]
    ++ ["-i" ++ l | l <- nub (hsSourceDirs bi)]
    ++ ["-i" ++ autogenModulesDir lbi]
       -- output path
    ++ ["--odir=" ++ odir]
       -- optimization
    ++ (case withOptimization lbi of
          NoOptimisation       ->  ["-O0"]
          NormalOptimisation   ->  ["-O1"]
          MaximumOptimisation  ->  ["-O2"])
  
  uhcPackageDbOptions :: FilePath -> FilePath -> PackageDBStack -> [String]
  uhcPackageDbOptions user system db = map (\ x -> "--pkg-searchpath=" ++ x)
                                           (concatMap (packageDbPaths user system) db)
  
  -- -----------------------------------------------------------------------------
  -- Installation
  
  installLib :: Verbosity -> LocalBuildInfo
             -> FilePath -> FilePath -> FilePath
             -> PackageDescription -> Library -> IO ()
  installLib verbosity _lbi targetDir _dynlibTargetDir builtDir pkg _library = do
      -- putStrLn $ "dest:  " ++ targetDir
      -- putStrLn $ "built: " ++ builtDir
      installDirectoryContents verbosity (builtDir </> display (packageId pkg)) targetDir
  
  -- currently hardcoded UHC code generator and variant to use
  uhcTarget, uhcTargetVariant :: String
  uhcTarget        = "bc"
  uhcTargetVariant = "plain"
  
  -- root directory for a package in UHC
  uhcPackageDir    :: String -> String -> FilePath
  uhcPackageSubDir ::           String -> FilePath
  uhcPackageDir    pkgid compilerid = pkgid </> uhcPackageSubDir compilerid
  uhcPackageSubDir       compilerid = compilerid </> uhcTarget </> uhcTargetVariant
  
  -- -----------------------------------------------------------------------------
  -- Registering
  
  registerPackage
    :: Verbosity
    -> InstalledPackageInfo
    -> PackageDescription
    -> LocalBuildInfo
    -> Bool
    -> PackageDBStack
    -> IO ()
  registerPackage verbosity installedPkgInfo pkg lbi inplace _packageDbs = do
      let installDirs = absoluteInstallDirs pkg lbi NoCopyDest
          pkgdir  | inplace   = buildDir lbi       </> uhcPackageDir    (display pkgid) (display compilerid)
                  | otherwise = libdir installDirs </> uhcPackageSubDir                 (display compilerid)
      createDirectoryIfMissingVerbose verbosity True pkgdir
      writeUTF8File (pkgdir </> installedPkgConfig)
                    (showInstalledPackageInfo installedPkgInfo)
    where
      pkgid      = packageId pkg
      compilerid = compilerId (compiler lbi)
  