{-|
  The FileBase module provides basic operations that can be used
  on file-related objects.

  This module provides the utility operators '///' and 'pathsplit'.
  The former is used to join two path elements, providing a path
  separator as needed, and the latter splits a path into the directory
  and filename portions.

  >   pathsplit ("foo" /// "bar" /// "cow") == ("foo/bar", "cow")

  >   snd . pathsplit . fst . pathsplit "foo/bar/cow" == "bar"

-}

module FSOps.FileBase (
                 -- ** Utility Functions
                 (///), pathsplit,
		 )
    where

import Data.List

-- |Join two path elements without duplicating path separator chars

(///) :: String -> String -> String
(///) dir file = if   (isSuffixOf "/" dir) 
                 then dir ++ file 
                 else dir ++ "/" ++ file

-- |Split a path into a tuple (directory, filename).

pathsplit :: String -> (String, String)
pathsplit p = let    pathto   = reverse . snd . rsplit . reverse
                     filename = reverse . fst . rsplit . reverse
                     rsplit :: String -> (String, String)
                     rsplit ('/':rs) = rsplit rs
                     rsplit r@_      = span (\c -> c /= '/') r
                 in ((pathto p), (filename p))