module Main where

import Paths_yjtools_unix (getDataFileName)
import Text.RegexPR       (matchRegexPR)
import System.Directory   (getDirectoryContents)
import Data.List          (isSuffixOf)
import Data.Maybe         (fromJust)
import Distribution.PackageDescription
import Distribution.PackageDescription.Parse
import Distribution.Verbosity
import System.Environment (getArgs)

main :: IO ()
main = do
  [ fn, crYear, mdfYear ] <- getArgs
  cabalCont <- getDirectoryContents "." >>= readFile . head . filter (isSuffixOf ".cabal")
  prgName   <- getDirectoryContents "." >>= readCabal . head . filter (isSuffixOf ".cabal") >>= return
    . fst . head
--    . filter ((==fn).modulePath.condTreeData.snd)
    . condExecutables
  let getField fld = snd . head . snd . fromJust . matchRegexPR ("(?i)" ++ fld ++ "\\:\\s*(.+)")
      synopsis = getField "synopsis" cabalCont
  header <-  mkCopyright prgName synopsis (read crYear) (read mdfYear)
	                 "Yoshikuni Jujo" "PAF01143@nifty.ne.jp"
  putStr header
  cont <- readFile fn
  putStr $ take (length cont - length cont) "dummy"
  writeFile fn $ header ++ cont

-- addCopyright :: FilePath -> String -> String -> Int -> Int -> String -> String -> IO ()
-- addCopyright fn prgName synopsis crYear mdfYear author address

mkCopyright :: String -> String -> Int -> Int -> String -> String -> IO String
mkCopyright prgName synopsis crYear mdfYear author address = do
  gplHeader <- getDataFileName "gpl_header.txt" >>= readFile
  return $
    "{- " ++ prgName ++ ": " ++ synopsis ++ "\n" ++
    "Copyright (C) " ++ show crYear ++ "-" ++ show mdfYear ++ " " ++ author ++
    " <" ++ address ++ ">\n\n" ++ gplHeader ++ "-}\n\n"

readCabal :: FilePath -> IO GenericPackageDescription
readCabal = readPackageDescription normal