1 files changed, 66 insertions, 0 deletions
diff --git a/bin/UnsetEnv.hs b/bin/UnsetEnv.hs
new file mode 100644
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--- /dev/null
+++ b/bin/UnsetEnv.hs
@@ -0,0 +1,66 @@
+-- |
+-- Copyright   : (c) 2015 Egor Tensin <Egor.Tensin@gmail.com>
+-- License     : MIT
+-- Maintainer  : Egor.Tensin@gmail.com
+-- Stability   : experimental
+-- Portability : Windows-only
+
+module Main (main) where
+
+import Control.Monad   (void)
+import Control.Monad.Trans.Except (runExceptT)
+import System.IO.Error (ioError)
+
+import Options.Applicative
+
+import qualified WindowsEnv
+
+import Prompt
+import PromptMessage
+
+data Options = Options
+    { optYes    :: Bool
+    , optGlobal :: Bool
+    , optName   :: WindowsEnv.VarName
+    } deriving (Eq, Show)
+
+optionParser :: Parser Options
+optionParser = Options
+    <$> optYesDesc
+    <*> optGlobalDesc
+    <*> optNameDesc
+  where
+    optYesDesc = switch
+         $ long "yes" <> short 'y'
+        <> help "Skip confirmation prompt"
+    optGlobalDesc = switch
+         $ long "global" <> short 'g'
+        <> help "Unset for all users"
+    optNameDesc = argument str
+         $ metavar "NAME"
+        <> help "Variable name"
+
+main :: IO ()
+main = execParser parser >>= unsetEnv
+  where
+    parser = info (helper <*> optionParser) $
+        fullDesc <> progDesc "Delete environment variables"
+
+unsetEnv :: Options -> IO ()
+unsetEnv options = runExceptT doUnsetEnv >>= either ioError return
+  where
+    varName = optName options
+
+    forAllUsers = optGlobal options
+    profile
+        | forAllUsers = WindowsEnv.AllUsers
+        | otherwise   = WindowsEnv.CurrentUser
+
+    skipPrompt = optYes options
+    promptAnd
+        | skipPrompt = withoutPrompt
+        | otherwise  = withPrompt $ wipeMessage profile varName
+
+    wipe = WindowsEnv.wipe profile varName
+
+    doUnsetEnv = void $ promptAnd wipe