module Main( main ) where

import System.Console.GetOpt

import System.Environment

import System.Exit

import System.IO

import Data.Maybe( fromMaybe )

import Pas2C

main = do

    args <- getArgs

    if length args == 0

    then do

        name <- getProgName

        hPutStrLn stderr $ usageInfo header options

        exitFailure

    else do

        case getOpt RequireOrder options args of

          (flags, [],      [])     ->

            if length args == 8 then do

                pas2C (args !! 1) ((args !! 3)++"/") ((args !! 5)++"/") ((args !! 7)++"/")

            else do

                if length args == 6 then do

                    pas2C (args !! 1) ((args !! 3)++"/") ((args !! 5)++"/") "./"

                else do

                    error $ usageInfo header options

          (_,     nonOpts, [])     -> error $ "unrecognized arguments: " ++ unwords nonOpts

          (_,     _,       msgs)   -> error $ usageInfo header options

    where header = "Freepascal to C conversion! Please use -n -i -o -a options in this order.\n"

data Flag = HelpMessage | Name String | Input String | Output String | Alternate String

options :: [OptDescr Flag]

options = [

    Option ['h'] ["help"]      (NoArg HelpMessage)      "print this help message",

    Option ['n'] ["name"]      (ReqArg Name "MAIN")     "name of the main Pascal module",

    Option ['i'] ["input"]     (ReqArg Input "DIR")     "input directory, where .pas files will be read",

    Option ['o'] ["output"]    (ReqArg Output "DIR")    "output directory, where .c/.h files will be written",

    Option ['a'] ["alternate"] (ReqArg Alternate "DIR") "alternate input directory, for out of source builds"

  ]