{- Copyright © 2015 Benjamin Barenblat

This program is free software: you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation, either version 3 of the License, or (at your option) any later
version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.  See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with
this program.  If not, see <http://www.gnu.org/licenses/>. -}

module Main where

import System.Environment (getArgs)
import System.Exit (exitFailure)

import Fragment (parseFile, parseStdin)
import Tangle (tangle)

main :: IO ()
main = do
  args <- getArgs
  parsed <- case args of
              [] -> parseStdin
              [f] -> parseFile f
              _ -> usage >> exitFailure
  case parsed of
    Left err -> print err >> exitFailure
    Right ok -> print $ tangle ok

usage :: IO ()
usage = putStrLn "usage: lyt [file]"