-- | This module provides type-safe access to directory manipulations.
--
--   It is designed to be imported instead of "System.Directory".
--   (It is intended to provide versions of functions from that
--   module which have equivalent functionality but are more
--   typesafe). "System.Path" is a companion module providing
--   a type-safe alternative to "System.FilePath".
--
--   You will typically want to import as follows:
--
--   > import Prelude hiding (FilePath)
--   > import System.Path
--   > import System.Path.Directory
--   > import System.Path.IO
--
--
-- Ben Moseley - (c) 2009
--
module System.Path.Directory
(
  -- * Actions on directories
  createDirectory,
  createDirectoryIfMissing,
  removeDirectory,
  removeDirectoryRecursive,
  renameDirectory,

  getDirectoryContents,
  absDirectoryContents,
  relDirectoryContents,
  filesInDir,
  dirsInDir,

  getCurrentDirectory,
  setCurrentDirectory,

  -- * Pre-defined directories
  getHomeDirectory,
  getAppUserDataDirectory,
  getUserDocumentsDirectory,
  getTemporaryDirectory,

  -- * Actions on files
  removeFile,
  renameFile,
  copyFile,
  canonicalizePath,
  makeRelativeToCurrentDirectory,
  findExecutable,

  -- * Existence tests
  doesFileExist,
  doesDirectoryExist,

  -- * Permissions
  Permissions,
  getPermissions,
  setPermissions,

  -- * Timestamps
  getModificationTime
)

where

import System.Path
import System.Path.ModificationTime (convertTime)
import Data.Time (UTCTime)

import qualified System.Directory as SD
import System.Directory (Permissions)

import Control.Applicative ((<$>))

import Data.List (partition)

import Prelude hiding (FilePath)


------------------------------------------------------------------------
-- Actions on directories

createDirectory :: AbsRelClass ar => DirPath ar -> IO ()
createDirectory = SD.createDirectory . getPathString

createDirectoryIfMissing :: AbsRelClass ar => Bool -> DirPath ar -> IO ()
createDirectoryIfMissing flag = SD.createDirectoryIfMissing flag . getPathString

removeDirectory :: AbsRelClass ar => DirPath ar -> IO ()
removeDirectory = SD.removeDirectory . getPathString

removeDirectoryRecursive :: AbsRelClass ar => DirPath ar -> IO ()
removeDirectoryRecursive = SD.removeDirectoryRecursive . getPathString

renameDirectory :: (AbsRelClass ar1, AbsRelClass ar2) => DirPath ar1 -> DirPath ar2 -> IO ()
renameDirectory p1 p2 = SD.renameDirectory (getPathString p1) (getPathString p2)

-- | An alias for 'relDirectoryContents'.
getDirectoryContents :: AbsRelClass ar => DirPath ar -> IO ([RelDir], [RelFile])
getDirectoryContents = relDirectoryContents

-- | Retrieve the contents of a directory path (which may be relative) as absolute paths
absDirectoryContents :: AbsRelClass ar => DirPath ar -> IO ([AbsDir], [AbsFile])
absDirectoryContents p = do
  cd <- asAbsDir <$> SD.getCurrentDirectory
  let dir = absRel id (cd </>) p
  (rds, rfs) <- relDirectoryContents dir
  return (map (dir </>) rds, map (dir </>) rfs)

-- | Returns paths relative /to/ the supplied (abs or relative) directory path.
--   eg (for current working directory of @\/somewhere\/cwd\/@):
--
-- > show (relDirectoryContents "d/e/f/") == (["subDir1A","subDir1B"],
-- >                                                      ["file1A","file1B"])
--
relDirectoryContents :: AbsRelClass ar => DirPath ar -> IO ([RelDir], [RelFile])
relDirectoryContents dir = do
  filenames <- filter (not . flip elem [".",".."]) <$> SD.getDirectoryContents (getPathString dir)
  dirFlags  <- mapM (doesDirectoryExist . (dir </>) . asRelPath) filenames
  let fileinfo = zip filenames dirFlags
      (dirs, files) = partition snd fileinfo
  return (map (combine currentDir . asRelDir . fst) dirs,
          map (combine currentDir . asRelFile . fst) files)

-- | A convenient alternative to 'relDirectoryContents' if you only want files.
filesInDir :: AbsRelClass ar => DirPath ar -> IO [RelFile]
filesInDir dir = snd <$> relDirectoryContents dir

-- | A convenient alternative to 'relDirectoryContents' if you only want directories.
dirsInDir :: AbsRelClass ar => DirPath ar -> IO [RelDir]
dirsInDir dir = fst <$> relDirectoryContents dir


getCurrentDirectory :: IO AbsDir
getCurrentDirectory = asAbsDir <$> SD.getCurrentDirectory

setCurrentDirectory :: AbsRelClass ar => DirPath ar -> IO ()
setCurrentDirectory = SD.setCurrentDirectory . getPathString


------------------------------------------------------------------------
-- Pre-defined directories

getHomeDirectory :: IO AbsDir
getHomeDirectory = asAbsDir <$> SD.getHomeDirectory

getAppUserDataDirectory :: String -> IO AbsDir
getAppUserDataDirectory user = asAbsDir <$> SD.getAppUserDataDirectory user

getUserDocumentsDirectory :: IO AbsDir
getUserDocumentsDirectory = asAbsDir <$> SD.getUserDocumentsDirectory

getTemporaryDirectory :: IO AbsDir
getTemporaryDirectory = asAbsDir <$> SD.getTemporaryDirectory


------------------------------------------------------------------------
-- Actions on files

removeFile :: AbsRelClass ar => FilePath ar -> IO ()
removeFile = SD.removeFile . getPathString

renameFile :: (AbsRelClass ar1, AbsRelClass ar2) => FilePath ar1 -> FilePath ar2 -> IO ()
renameFile p1 p2 = SD.renameFile (getPathString p1) (getPathString p2)

copyFile :: (AbsRelClass ar1, AbsRelClass ar2) => FilePath ar1 -> FilePath ar2 -> IO ()
copyFile p1 p2 = SD.copyFile (getPathString p1) (getPathString p2)

canonicalizePath :: AbsRelClass ar => Path ar fd -> IO (AbsPath fd)
canonicalizePath p = asPath <$> SD.canonicalizePath (getPathString p)

makeRelativeToCurrentDirectory :: AbsRelClass ar => Path ar fd -> IO (RelPath fd)
makeRelativeToCurrentDirectory p = asPath <$> SD.makeRelativeToCurrentDirectory (getPathString p)

findExecutable :: String -> IO (Maybe AbsFile)
findExecutable s = fmap asPath <$> SD.findExecutable s


------------------------------------------------------------------------
-- Existence tests

doesFileExist :: AbsRelClass ar => FilePath ar -> IO Bool
doesFileExist = SD.doesFileExist . getPathString

doesDirectoryExist :: AbsRelClass ar => DirPath ar -> IO Bool
doesDirectoryExist = SD.doesDirectoryExist . getPathString


------------------------------------------------------------------------
-- Permissions

getPermissions :: AbsRelClass ar => Path ar fd -> IO Permissions
getPermissions p = SD.getPermissions (getPathString p)

setPermissions :: AbsRelClass ar => Path ar fd -> Permissions -> IO ()
setPermissions p perms = SD.setPermissions (getPathString p) perms


------------------------------------------------------------------------
-- Timestamps

getModificationTime :: AbsRelClass ar => Path ar fd -> IO UTCTime
getModificationTime p = convertTime <$> SD.getModificationTime (getPathString p)