-- Copyright (C) 2002-2003 David Roundy
--
-- 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 2, 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; see the file COPYING.  If not, write to
-- the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
-- Boston, MA 02110-1301, USA.

{-# OPTIONS_GHC -cpp #-}
{-# LANGUAGE CPP #-}

module Main (main) where

import System.IO ( hSetBinaryMode)
import System.IO ( stdin, stdout )
import System.Exit ( exitWith, ExitCode(..) )
import System.Environment ( getArgs )
import Control.Monad ( when )
import Control.Exception ( Exception( AssertionFailed ), handleJust, catchDyn )

import Darcs.RunCommand ( run_the_command )
import Darcs.Flags ( DarcsFlag(Verbose) )
import Darcs.Commands.Help ( help_cmd, list_available_commands, print_version )
import Autoconf( darcs_version )
import Darcs.SignalHandler ( withSignalsHandled )
import Context ( context )
import Darcs.Global ( with_atexit )
import Exec ( ExecException(..) )
#include "impossible.h"

assertions :: Control.Exception.Exception -> Maybe String
assertions (AssertionFailed s) = Just s
assertions _ = Nothing

execExceptionHandler :: ExecException -> IO a
execExceptionHandler (ExecException cmd args redirects reason) =
    do putStrLn $ "Failed to execute external command: " ++ unwords (cmd:args) ++ "\n"
                    ++ "Lowlevel error: " ++ reason ++ "\n"
                    ++ "Redirects: " ++ show redirects ++"\n"
       exitWith $ ExitFailure 3

main :: IO ()
main = with_atexit $ withSignalsHandled $
  flip catchDyn execExceptionHandler $
  handleJust assertions bug $ do
  argv <- getArgs;
  when (length argv < 1) $
       do print_version
          help_cmd [] []
  when (length argv == 1 && (argv!!0 == "-h" || argv!!0 == "--help")) $
       help_cmd [] []
  when (length argv == 1 && (argv!!0 == "--overview")) $
       help_cmd [Verbose] []
  when (length argv == 1 && (argv!!0 == "-v" || argv!!0 == "--version")) $
       do putStrLn darcs_version
          exitWith $ ExitSuccess
  when (length argv == 1 && (argv!!0 == "--exact-version")) $
       do putStrLn $ "darcs compiled on "++__DATE__++", at "++__TIME__
          putStrLn context
          exitWith $ ExitSuccess
  when (length argv == 1 && argv!!0 == "--commands") $
       do list_available_commands
          exitWith $ ExitSuccess
  hSetBinaryMode stdin True
  hSetBinaryMode stdout True
  run_the_command (head argv) (tail argv)