Clean up a bunch of code and comments.

[dead/halcyon.git] / src / OptionalConfiguration.hs

diff --git a/src/OptionalConfiguration.hs b/src/OptionalConfiguration.hs
index 53635439ac354c76bc1f9d96d074fac6ee89254c..8fd9f6c68319d204a94efc4e3a9d17f052124758 100644 (file)
--- a/src/OptionalConfiguration.hs
+++ b/src/OptionalConfiguration.hs
@@ -1,20 +1,42 @@
+{-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE OverloadedStrings #-}
 
--- | The program will parse ~/.twatrc for any available configuration
+-- | The program will parse ~/.halcyonrc for any available configuration
 --   directives, resulting in an OptionalCfg. The command-line
 --   arguments will be used to create another OptionalCfg, and the two
 --   will be merged. Finally, a default_config will be updated from
 --   the merged OptionalCfgs.
 --
 
-module OptionalConfiguration
+module OptionalConfiguration (
+  OptionalCfg(..),
+  from_rc )
 where
 
-import Data.Monoid (Monoid(..))
-import qualified Data.Configurator as DC
+import qualified Data.Configurator as DC (
+  Worth (Optional),
+  load,
+  lookup )
 
--- The same as Cfg, except everything is optional. It's easy to merge
--- two of these by simply dropping the Nothings in favor of the Justs.
+import Data.Data ( Data )
+import Data.Maybe ( fromMaybe )
+import Data.Monoid ( Monoid(..) )
+import Data.Typeable ( Typeable )
+import Paths_halcyon ( getSysconfDir )
+import System.Directory ( getHomeDirectory )
+import System.FilePath ( (</>) )
+import System.IO ( hPutStrLn, stderr )
+import System.IO.Error ( catchIOError )
+
+import Usernames ( Usernames(..) )
+
+
+-- | The same as Cfg, except everything is optional. It's easy to
+--   merge two of these by simply dropping the Nothings in favor of
+--   the Justs. The 'usernames' are left un-maybed so that cmdargs
+--   can parse more than one of them.
+--
 data OptionalCfg =
   OptionalCfg { consumer_key :: Maybe String,
                 consumer_secret :: Maybe String,
@@ -26,7 +48,9 @@ data OptionalCfg =
                 sendmail_path :: Maybe String,
                 from_address :: Maybe String,
                 to_address :: Maybe String,
-                verbose :: Maybe Bool }
+                verbose :: Maybe Bool,
+                usernames :: Usernames }
+    deriving (Show, Data, Typeable)
 
 instance Monoid OptionalCfg where
   mempty = OptionalCfg
@@ -41,6 +65,7 @@ instance Monoid OptionalCfg where
              Nothing
              Nothing
              Nothing
+             (Usernames [])
 
   cfg1 `mappend` cfg2 =
     OptionalCfg
@@ -55,6 +80,7 @@ instance Monoid OptionalCfg where
       (merge (from_address cfg1) (from_address cfg2))
       (merge (to_address cfg1) (to_address cfg2))
       (merge (verbose cfg1) (verbose cfg2))
+      all_usernames
     where
       merge :: (Maybe a) -> (Maybe a) -> (Maybe a)
       merge Nothing Nothing   = Nothing
@@ -62,9 +88,35 @@ instance Monoid OptionalCfg where
       merge Nothing (Just x)  = Just x
       merge (Just _) (Just y) = Just y
 
+      -- Use only the latter usernames if there are any.
+      all_usernames =
+        usernames $ if (null (get_usernames (usernames cfg2)))
+                    then cfg1
+                    else cfg2
+
+
+-- | Obtain an 'OptionalCfg' from halcyonrc in either the global
+--   configuration directory or the user's home directory. The one in
+--   $HOME is prefixed by a dot so that it is hidden.
+--
+--   We make an attempt at cross-platform compatibility; we will try
+--   to find the correct directory even on Windows. But if the calls
+--   to getHomeDirectory/getSysconfDir fail for whatever reason, we
+--   fall back to using the Unix-specific /etc and $HOME.
+--
 from_rc :: IO OptionalCfg
 from_rc = do
-  cfg <- DC.load [ DC.Optional "$(HOME)/.twatrc" ]
+  etc  <- catchIOError getSysconfDir (\e -> do
+                                        hPutStrLn stderr (show e)
+                                        return "/etc")
+  home <- catchIOError getHomeDirectory (\e -> do
+                                           hPutStrLn stderr (show e)
+                                           return "$(HOME)")
+  let global_config_path = etc </> "halcyonrc"
+  let user_config_path = home </> ".halcyonrc"
+  cfg <- DC.load [ DC.Optional global_config_path,
+                   DC.Optional user_config_path ]
+
   cfg_consumer_key <- DC.lookup cfg "consumer-key"
   cfg_consumer_secret <- DC.lookup cfg "consumer-secret"
   cfg_access_token <- DC.lookup cfg "access-token"
@@ -76,6 +128,8 @@ from_rc = do
   cfg_from_address <- DC.lookup cfg "from"
   cfg_to_address <- DC.lookup cfg "to"
   cfg_verbose <- DC.lookup cfg "verbose"
+  cfg_usernames <- DC.lookup cfg "usernames"
+
   return $ OptionalCfg
              cfg_consumer_key
              cfg_consumer_secret
@@ -88,4 +142,4 @@ from_rc = do
              cfg_from_address
              cfg_to_address
              cfg_verbose
-
+             (fromMaybe (Usernames []) cfg_usernames)