    -----------------------------------------------------------------------------
    -- |
    -- Module      :  Distribution.Simple.LocalBuildInfo
    -- Copyright   :  Isaac Jones 2003-2004
    --
    -- Maintainer  :  cabal-devel@haskell.org
    -- Portability :  portable
    --
    -- Once a package has been configured we have resolved conditionals and
    -- dependencies, configured the compiler and other needed external programs.
    -- The 'LocalBuildInfo' is used to hold all this information. It holds the
    -- install dirs, the compiler, the exact package dependencies, the configured
    -- programs, the package database to use and a bunch of miscellaneous configure
    -- flags. It gets saved and reloaded from a file (@dist\/setup-config@). It gets
    -- passed in to very many subsequent build actions.

    {- 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.LocalBuildInfo (
            LocalBuildInfo(..),
            externalPackageDeps,
            inplacePackageId,
            withLibLBI,
            withExeLBI,
            withTestLBI,
            ComponentLocalBuildInfo(..),
            -- * Installation directories
            module Distribution.Simple.InstallDirs,
            absoluteInstallDirs, prefixRelativeInstallDirs,
            substPathTemplate
      ) where

    import Distribution.Simple.InstallDirs hiding (absoluteInstallDirs,
                                                   prefixRelativeInstallDirs,
                                                   substPathTemplate, )
    import qualified Distribution.Simple.InstallDirs as InstallDirs
    import Distribution.Simple.Program (ProgramConfiguration)
    import Distribution.PackageDescription
             ( PackageDescription(..), withLib, Library, withExe
             , Executable(exeName), withTest, TestSuite(..) )
    import Distribution.Package
             ( PackageId, Package(..), InstalledPackageId(..) )
    import Distribution.Simple.Compiler
             ( Compiler(..), PackageDBStack, OptimisationLevel )
    import Distribution.Simple.PackageIndex
             ( PackageIndex )
    import Distribution.Simple.Utils
             ( die )
    import Distribution.Simple.Setup
             ( ConfigFlags )
    import Distribution.Text
             ( display )

    import Data.List (nub)

    -- | Data cached after configuration step.  See also
    -- 'Distribution.Simple.Setup.ConfigFlags'.
    data LocalBuildInfo = LocalBuildInfo {
            configFlags   :: ConfigFlags,
            -- ^ Options passed to the configuration step.
            -- Needed to re-run configuration when .cabal is out of date
            extraConfigArgs     :: [String],
            -- ^ Extra args on the command line for the configuration step.
            -- Needed to re-run configuration when .cabal is out of date
            installDirTemplates :: InstallDirTemplates,
                    -- ^ The installation directories for the various differnt
                    -- kinds of files
            --TODO: inplaceDirTemplates :: InstallDirs FilePath
            compiler      :: Compiler,
                    -- ^ The compiler we're building with
            buildDir      :: FilePath,
                    -- ^ Where to build the package.
            --TODO: eliminate hugs's scratchDir, use builddir
            scratchDir    :: FilePath,
                    -- ^ Where to put the result of the Hugs build.
            libraryConfig       :: Maybe ComponentLocalBuildInfo,
            executableConfigs   :: [(String, ComponentLocalBuildInfo)],
            testSuiteConfigs    :: [(String, ComponentLocalBuildInfo)],
            installedPkgs :: PackageIndex,
                    -- ^ All the info about the installed packages that the
                    -- current package depends on (directly or indirectly).
            pkgDescrFile  :: Maybe FilePath,
                    -- ^ the filename containing the .cabal file, if available
            localPkgDescr :: PackageDescription,
                    -- ^ The resolved package description, that does not contain
                    -- any conditionals.
            withPrograms  :: ProgramConfiguration, -- ^Location and args for all programs
            withPackageDB :: PackageDBStack,  -- ^What package database to use, global\/user
            withVanillaLib:: Bool,  -- ^Whether to build normal libs.
            withProfLib   :: Bool,  -- ^Whether to build profiling versions of libs.
            withSharedLib :: Bool,  -- ^Whether to build shared versions of libs.
            withProfExe   :: Bool,  -- ^Whether to build executables for profiling.
            withOptimization :: OptimisationLevel, -- ^Whether to build with optimization (if available).
            withGHCiLib   :: Bool,  -- ^Whether to build libs suitable for use with GHCi.
            splitObjs     :: Bool,  -- ^Use -split-objs with GHC, if available
            stripExes     :: Bool,  -- ^Whether to strip executables during install
            progPrefix    :: PathTemplate, -- ^Prefix to be prepended to installed executables
            progSuffix    :: PathTemplate -- ^Suffix to be appended to installed executables
      } deriving (Read, Show)

    data ComponentLocalBuildInfo = ComponentLocalBuildInfo {
        -- | Resolved internal and external package dependencies for this component.
        -- The 'BuildInfo' specifies a set of build dependencies that must be
        -- satisfied in terms of version ranges. This field fixes those dependencies
        -- to the specific versions available on this machine for this compiler.
        componentPackageDeps :: [(InstalledPackageId, PackageId)]
      }
      deriving (Read, Show)

    -- | External package dependencies for the package as a whole. This is the
    -- union of the individual 'componentPackageDeps', less any internal deps.
    externalPackageDeps :: LocalBuildInfo -> [(InstalledPackageId, PackageId)]
    externalPackageDeps lbi = filter (not . internal . snd) $ nub $
      -- TODO:  what about non-buildable components?
           maybe [] componentPackageDeps (libraryConfig lbi)
        ++ concatMap (componentPackageDeps . snd) (executableConfigs lbi)
      where
        -- True if this dependency is an internal one (depends on the library
        -- defined in the same package).
        internal pkgid = pkgid == packageId (localPkgDescr lbi)

    -- | The installed package Id we use for local packages registered in the local
    -- package db. This is what is used for intra-package deps between components.
    --
    inplacePackageId :: PackageId -> InstalledPackageId
    inplacePackageId pkgid = InstalledPackageId (display pkgid ++ "-inplace")

    -- |If the package description has a library section, call the given
    --  function with the library build info as argument.  Extended version of
    -- 'withLib' that also gives corresponding build info.
    withLibLBI :: PackageDescription -> LocalBuildInfo
               -> (Library -> ComponentLocalBuildInfo -> IO ()) -> IO ()
    withLibLBI pkg_descr lbi f = withLib pkg_descr $ \lib ->
      case libraryConfig lbi of
        Just clbi -> f lib clbi
        Nothing   -> die $ "internal error: the package contains a library "
                        ++ "but there is no corresponding configuration data"

    -- | Perform the action on each buildable 'Executable' in the package
    -- description.  Extended version of 'withExe' that also gives corresponding
    -- build info.
    withExeLBI :: PackageDescription -> LocalBuildInfo
               -> (Executable -> ComponentLocalBuildInfo -> IO ()) -> IO ()
    withExeLBI pkg_descr lbi f = withExe pkg_descr $ \exe ->
      case lookup (exeName exe) (executableConfigs lbi) of
        Just clbi -> f exe clbi
        Nothing   -> die $ "internal error: the package contains an executable "
                        ++ exeName exe ++ " but there is no corresponding "
                        ++ "configuration data"

    withTestLBI :: PackageDescription -> LocalBuildInfo
                -> (TestSuite -> ComponentLocalBuildInfo -> IO ()) -> IO ()
    withTestLBI pkg_descr lbi f =
        let wrapper test = case lookup (testName test) (testSuiteConfigs lbi) of
                Just clbi -> f test clbi
                Nothing -> die $ "internal error: the package contains a test suite "
                                ++ testName test ++ " but there is no corresponding "
                                ++ "configuration data"
        in withTest pkg_descr wrapper

    -- -----------------------------------------------------------------------------
    -- Wrappers for a couple functions from InstallDirs

    -- |See 'InstallDirs.absoluteInstallDirs'
    absoluteInstallDirs :: PackageDescription -> LocalBuildInfo -> CopyDest
                        -> InstallDirs FilePath
    absoluteInstallDirs pkg lbi copydest =
      InstallDirs.absoluteInstallDirs
        (packageId pkg)
        (compilerId (compiler lbi))
        copydest
        (installDirTemplates lbi)

    -- |See 'InstallDirs.prefixRelativeInstallDirs'
    prefixRelativeInstallDirs :: PackageId -> LocalBuildInfo
                              -> InstallDirs (Maybe FilePath)
    prefixRelativeInstallDirs pkg_descr lbi =
      InstallDirs.prefixRelativeInstallDirs
        (packageId pkg_descr)
        (compilerId (compiler lbi))
        (installDirTemplates lbi)

    substPathTemplate :: PackageId -> LocalBuildInfo
                      -> PathTemplate -> FilePath
    substPathTemplate pkgid lbi = fromPathTemplate
                                    . ( InstallDirs.substPathTemplate env )
        where env = initialPathTemplateEnv
                       pkgid
                       (compilerId (compiler lbi))