module Propellor.PrivData where

import qualified Data.Map as M
import Control.Applicative
import System.FilePath
import System.IO
import System.Directory
import Data.Maybe
import Control.Monad

import Propellor.Types
import Propellor.Property
import Utility.Monad
import Utility.PartialPrelude
import Utility.Exception
import Utility.Process
import Utility.Tmp
import Utility.SafeCommand
import Utility.Misc

{- | Note that removing or changing field names will break the
 - serialized privdata files, so don't do that!
 - It's fine to add new fields. -}
data PrivDataField
	= DockerAuthentication
	| SshPrivKey UserName
	| Password UserName
	deriving (Read, Show, Ord, Eq)

withPrivData :: PrivDataField -> (String -> IO Result) -> IO Result
withPrivData field a = maybe missing a =<< getPrivData field
  where
	missing = do
		warningMessage $ "Missing privdata " ++ show field
		return FailedChange

getPrivData :: PrivDataField -> IO (Maybe String)
getPrivData field = do
	m <- catchDefaultIO Nothing $ readish <$> readFile privDataLocal
	return $ maybe Nothing (M.lookup field) m

setPrivData :: HostName -> PrivDataField -> IO ()
setPrivData host field = do
	putStrLn "Enter private data on stdin; ctrl-D when done:"
	value <- hGetContentsStrict stdin
	makePrivDataDir
	let f = privDataFile host
	m <- fromMaybe M.empty . readish <$> gpgDecrypt f
	let m' = M.insert field value m
	gpgEncrypt f (show m')
	putStrLn "Private data set."
	void $ boolSystem "git" [Param "add", File f]

makePrivDataDir :: IO ()
makePrivDataDir = createDirectoryIfMissing False privDataDir

privDataDir :: FilePath
privDataDir = "privdata"

privDataFile :: HostName -> FilePath
privDataFile host = privDataDir </> host ++ ".gpg"

privDataLocal :: FilePath
privDataLocal = privDataDir </> "local"

privDataMarker :: String
privDataMarker = "PRIVDATA "

gpgDecrypt :: FilePath -> IO String
gpgDecrypt f = ifM (doesFileExist f)
	( readProcess "gpg" ["--decrypt", f]
	, return ""
	)

gpgEncrypt :: FilePath -> String -> IO ()
gpgEncrypt f s = do
	encrypted <- writeReadProcessEnv "gpg"
		[ "--default-recipient-self"
		, "--armor"
		, "--encrypt"
		]
		Nothing
		(Just $ flip hPutStr s)
		Nothing
	viaTmp writeFile f encrypted