module Main ( main ) where

import           MainNoPaths       ( getYavieDir )
import qualified MainNoPaths as NP ( main )

import System.Environment      ( getArgs )
import System.Directory        ( doesDirectoryExist, doesFileExist,
                                 createDirectory, createDirectoryIfMissing,
                                 copyFile )
import Control.Monad           ( when )

import Data.Version            ( showVersion )
import Paths_yavie             ( getDataFileName, version )

uuidFileName :: String
uuidFileName = "uuid_yavie"

defaultMains :: [ ( String, [ String ] ) ]
defaultMains = [ vtyFileNames, x11FileNames, gtkFileNames ]

vtyFileNames :: ( String, [ String ] )
vtyFileNames = ( "vty", [ "yavie-vty.hs", "yavie-vty.cabal" ] )

x11FileNames :: ( String, [ String ] )
x11FileNames = ( "x11", [ "yavie-x11.hs", "yavie-x11.cabal" ] )

gtkFileNames :: ( String, [ String ] )
gtkFileNames = ( "gtk", [ "yavie-gtk.hs", "yavie-gtk.cabal" ] )

main :: IO ()
main = do
  args      <- getArgs
  yavieDir  <- getYavieDir
  uuidYavie <- getDataFileName uuidFileName >>= readFile
  existYDir <- doesDirectoryExist yavieDir
  if existYDir then    checkYDir      yavieDir uuidYavie
               else do createUUIDFile yavieDir uuidYavie
                       mapM_ ( copyDefault yavieDir ) defaultMains
  case args of
       [ "--version" ] -> putStrLn $ "yavie " ++ showVersion version
       [ "--reset"   ] -> mapM_ ( copyDefault yavieDir ) defaultMains
       _               -> NP.main

checkYDir :: FilePath -> String -> IO ()
checkYDir yavieDir uuidYavie = do
  let uuidFile      = yavieDir ++ "/" ++ uuidFileName
      errMsg        = "checkYDir: bad yavie directory"
      errMsg2 yu du = "checkYDir : bad yavie directory " ++ show yu ++ " "
                                                         ++ show du
  existUFile <- doesFileExist uuidFile
  if not existUFile then error errMsg else do
    uuid <- readFile uuidFile
    when ( uuid /= uuidYavie ) $ error ( errMsg2 uuidYavie uuid )

createUUIDFile :: FilePath -> String -> IO ()
createUUIDFile yavieDir uuidYavie = do
  let uuidFile    = yavieDir ++ "/" ++ uuidFileName
      defaultFile = yavieDir ++ "/default"
  createDirectory yavieDir
  writeFile uuidFile uuidYavie
  writeFile defaultFile "vty\n"

copyDefault :: FilePath -> ( String, [ String ] ) -> IO ()
copyDefault yavieDir ( dirName, files ) = do
  let dir = yavieDir ++ "/" ++ dirName
  createDirectoryIfMissing False dir
  mapM_ ( copyToHome ( "src/" ++ dirName ) dir ) files

copyToHome :: FilePath -> FilePath -> FilePath -> IO ()
copyToHome fd td fn = do
  fromFile <- getDataFileName $ fd ++ "/" ++ fn
  let toFile   = td ++ "/" ++ fn
  copyFile fromFile toFile