-- | The information from Paths_shake cleaned up
module Development.Shake.Internal.Paths(
    shakeVersionString,
    initDataDirectory,
    hasManualData, copyManualData,
    readDataFileHTML
    ) where

import Paths_shake
import Control.Exception
import Control.Monad.Extra
import Data.Version
import System.Directory
import System.FilePath
import System.Info.Extra
import System.IO.Unsafe
import System.Environment
import General.Extra
import qualified Data.ByteString.Lazy as LBS


shakeVersionString :: String
shakeVersionString = showVersion version


-- We want getDataFileName to be relative to the current directory on program startup,
-- even if we issue a change directory command. Therefore, first call caches, future ones read.
{-# NOINLINE dataDirs #-}
dataDirs :: [String]
dataDirs = unsafePerformIO $ do
    datdir <- getDataDir
    exedir <- takeDirectory <$> getExecutablePath `catchIO` \_ -> return ""
    curdir <- getCurrentDirectory
    return $ [datdir] ++ [exedir | exedir /= ""] ++ [curdir]


-- The data files may be located relative to the current directory, if so cache it in advance
initDataDirectory :: IO ()
initDataDirectory = void $ evaluate dataDirs


getDataFile :: FilePath -> IO FilePath
getDataFile file = do
    let poss = map (</> file) dataDirs
    res <- filterM doesFileExist_ poss
    case res of
        [] -> fail $ unlines $ ("Could not find data file " ++ file ++ ", looked in:") : map ("  " ++) poss
        x:_ -> return x

hasDataFile :: FilePath -> IO Bool
hasDataFile file = anyM (\dir -> doesFileExist_ $ dir </> file) dataDirs


readDataFileHTML :: FilePath -> IO LBS.ByteString
readDataFileHTML file = LBS.readFile =<< getDataFile ("html" </> file)


manualFiles :: [FilePath]
manualFiles = map ("docs/manual" </>) ["Build.hs","main.c","constants.c","constants.h","build" <.> if isWindows then "bat" else "sh"]

hasManualData :: IO Bool
hasManualData = allM hasDataFile manualFiles

copyManualData :: FilePath -> IO ()
copyManualData dest = do
    createDirectoryRecursive dest
    forM_ manualFiles $ \file -> do
        src <- getDataFile file
        copyFile src (dest </> takeFileName file)