{-# LANGUAGE DoAndIfThenElse #-}
module Main
where

import System.IO (
  Handle,
  IOMode (WriteMode),
  openBinaryFile,
  stdout)

import CommandLine (show_help)
import Configuration (Cfg(..), get_cfg)
import LWN.Page (epublish, page_from_url)


-- | If we're given an empty path, return a handle to
--   'stdout'. Otherwise, open the given file and return a read/write
--   handle to that.
get_output_handle :: FilePath -> IO Handle
get_output_handle path =
  if (null path) then
    return stdout
  else
    openBinaryFile path WriteMode


main :: IO ()
main = do
  cfg <- get_cfg
  page <- page_from_url cfg (article cfg)
  case page of
    Just p -> do
      output_handle <- get_output_handle (output cfg)
      epublish p output_handle
    Nothing -> do
      _ <- show_help
      return ()