Remove Dhall dependency and ReaderT; use dotenv; create encryption key on startup if it doesn't exist

src/Core/Configuration.hs

@@ -1,11 +1,36 @@
-module Core.Configuration ( main ) where
+module Core.Configuration where
+
+import qualified Data.ByteString               as B
 
 import           Core.Types
+import           Crypto.Saltine.Core.SecretBox (newKey)
+import           Crypto.Saltine.Class          (encode)
+import           Configuration.Dotenv
+import           System.Directory              (doesFileExist)
+import           System.Environment            (getEnv)
 
-import           Dhall
-
-instance FromDhall DhallConfig
-
-main :: IO DhallConfig
+main :: IO ()
 main = do
-  input auto "./config.dhall"
+  loadFile defaultConfig
+
+keyFileInit :: IO ()
+keyFileInit = do
+  keyExists <- doesFileExist "./data/encryptionKey"
+  case keyExists of
+    True -> putStrLn "Using existing key"
+    False -> do
+      key <- newKey
+      B.writeFile "./data/encryptionKey" (encode key)
+      putStrLn "Creating new encryption key; any pre-existing DB entries will not decrypt"
+
+dbPath :: IO String
+dbPath = getEnv "dbFile"
+
+confLinkLength :: IO String
+confLinkLength = getEnv "linkLength"
+
+adminEmail :: IO String
+adminEmail = getEnv "adminEmail"
+
+appPort :: IO String
+appPort = getEnv "applicationPort"