improve gemini protocol cases

src/Gemini.hs

@@ -8,13 +8,16 @@ import System.Directory (doesDirectoryExist, doesFileExist)
 import Text.Regex
 import Text.Regex.PCRE
 
-
 getFile :: FilePath -> IO (Maybe String)
 getFile s = do
-  result <- try (readFile s) :: IO (Either SomeException String)
-  case result of
-    Left ex -> return Nothing
-    Right ex -> return (pure ex)
+  exists <- doesFileExist s
+  case exists of
+    True -> do
+      result <- try (readFile s) :: IO (Either SomeException String)
+      case result of
+        Left ex -> return Nothing
+        Right ex -> return (Just ex)
+    False -> return Nothing
 
 -- return components of the url
 -- gemini:// | hostname | uri | ? | query
@@ -66,9 +69,14 @@ parse_to_gemini tab =
       query = tab !! 0 !! 5
     }
 
-create_answer :: Gemini -> String -> String -> IO Answer
-create_answer (MkGemini domain file query) language basedir = do
-  content <- getFile $ basedir ++ file
+create_answer :: Gemini -> String -> String -> Bool -> IO Answer
+create_answer (MkGemini domain file query) language baseDir vhost = do
+  let baseDir' =
+        if vhost
+          then domain ++ "/" ++ baseDir
+          else baseDir
+
+  content <- getFile $ baseDir' ++ file
   case content of
     Just x ->
       return