Setup.hs

{-# LANGUAGE CPP                 #-}
{-# LANGUAGE DataKinds           #-}
{-# LANGUAGE ImportQualifiedPost #-}
{-# LANGUAGE OverloadedRecordDot #-}
{-# LANGUAGE OverloadedStrings   #-}
import Data.Either

import Distribution.Simple
import Distribution.Simple.Setup
import Distribution.Simple.LocalBuildInfo
import Distribution.PackageDescription
import Distribution.Types.BuildInfo
import Distribution.Types.PackageDescription
import Distribution.Types.CondTree
import Distribution.Types.ForeignLib
import Distribution.Types.UnqualComponentName
import Distribution.Utils.Path
import Distribution.Compat.Lens
import Distribution.Types.BuildInfo.Lens qualified as L

import Data.List (intercalate, nub)
import System.Process


main :: IO ()
main = defaultMainWithHooks $ simpleUserHooks
  { confHook = patchedConfHook }



patchedConfHook
  :: (GenericPackageDescription, HookedBuildInfo)
  -> ConfigFlags
  -> IO LocalBuildInfo
patchedConfHook (gpd, hbi) flags
  | Just True <- lookupFlagAssignment ("python3-config") $ configConfigurationsFlags flags
  = do cflags_raw  <- readProcess "python3-config" ["--cflags"] ""
       ldflags_raw <- readProcess "python3-config" ["--embed", "--ldflags"] ""
       -- Split flags
       let (inc_dirs,cflags) = partitionEithers
             [ case flag of
                 '-':'I':path -> Left  path
                 _            -> Right flag
             | flag <- tokenizeArguments cflags_raw
             ]
           (ldflags, (libs, lib_dirs)) = fmap partitionEithers $ partitionEithers
             [ case flag of
                 '-':'l':path -> Right (Left  path)
                 '-':'L':path -> Right (Right path)
                 _            -> Left flag
             | flag <- tokenizeArguments ldflags_raw
             ]
       let tweakLib lib = case lib.libName of
             LMainLibName -> lib & L.ccOptions    %~ (++ cflags)
                                 & L.includeDirs  %~ (++ (toSymb <$> inc_dirs))
                                 & L.ldOptions    %~ (++ ldflags)
                                 & L.extraLibs    %~ (++ libs)
                                 & L.extraLibDirs %~ (++ (toSymb <$> lib_dirs))
             _            -> lib
       confHook simpleUserHooks
         ( gpd { condLibrary = (fmap . fmap) tweakLib (condLibrary  gpd) }
         , hbi
         ) flags
  | otherwise = do
      confHook simpleUserHooks (gpd, hbi) flags

tokenizeArguments :: String -> [String]
tokenizeArguments = words

----------------------------------------------------------------
-- Compatibility

#if MIN_VERSION_Cabal_syntax(3,14,0)
toSymb :: String -> SymbolicPathX 'AllowAbsolute from to
toSymb = makeSymbolicPath
#else
toSymb :: String -> String
toSymb = id
#endif