don't store database file in home directory

Instead of being stored in ~/.passman.json, it will be stored in
~/.passman/database.json on *NIX and as database.json in the app data
directory on Windows

app/Main.hs

@@ -24,9 +24,12 @@ module Main where
 
 import Control.Monad (mapM_)
 import Control.Monad.Trans.State as S
-import Data.Maybe (maybe)
-import System.Console.HCL (Request, reqFail, reqIO, runRequest)
-import System.Environment (lookupEnv)
+import System.Console.HCL (Request, reqIO, runRequest)
+import System.EasyFile
+  ( createDirectoryIfMissing
+  , getAppUserDataDirectory
+  , (</>)
+  )
 import System.Random (getStdGen)
 
 import Types
@@ -45,24 +48,9 @@ setup = do
   return $ Status g pw p db
 
 getDBPath :: Request FilePath
-getDBPath = reqIO (lookupEnv "HOME") >>= maybe
-  (do
-    reqIO $ putStrLn "ERROR: can't find home directory"
-    reqFail)
-  (\home -> case pathDelim home of
-    Nothing -> do
-      reqIO $ putStrLn "ERROR: unsupported home path"
-      reqFail
-    Just delim -> return $ home ++
-      (if last home == delim then "" else [delim]) ++
-      ".passman.json")
-
-pathDelim :: FilePath -> Maybe Char
-pathDelim = foldr
-  (\x a -> case x of
-    '/'  -> Just '/'
-    '\\' -> Just '\\'
-    _    -> a)
-  Nothing
+getDBPath = reqIO $ do
+  path <- getAppUserDataDirectory "passman"
+  createDirectoryIfMissing True path
+  return $ path </> "database.json"
 
 --jl