1 files changed, 45 insertions, 0 deletions
diff --git a/src/Mail/Header.hs b/src/Mail/Header.hs
new file mode 100644
index 0000000..e7265b2
--- /dev/null
+++ b/src/Mail/Header.hs
@@ -0,0 +1,45 @@
+module Mail.Header
+  ( ContentType (..)
+  , Header
+  , contentType
+  , contentTransferEncoding
+  )
+where
+
+import Common (findVal, split2, splitOn, toLower, trim, trimWith)
+import Intro
+
+type Header = (String, String)
+
+data ContentType = ContentType
+  { mime :: String
+  , boundary :: Maybe String
+  , charset :: Maybe String
+  }
+  deriving (Show)
+
+newContentType :: String -> ContentType
+newContentType m = ContentType{mime = m, boundary = Nothing, charset = Nothing}
+
+contentType :: [Header] -> Maybe ContentType
+contentType xs = do
+  v <- findValIns "content-type" xs
+  case (fmap trim . splitOn (== ';')) v of
+    [y] -> pure (newContentType y)
+    y : ys ->
+      let kv = fmap (split2 (== '=')) ys
+       in pure
+            $ (newContentType y)
+              { boundary = trimQuotes <$> findValIns "boundary" kv
+              , charset = findValIns "charset" kv
+              }
+    [] -> Nothing
+
+contentTransferEncoding :: [Header] -> Maybe String
+contentTransferEncoding = findValIns "content-transfer-encoding"
+
+findValIns :: String -> [Header] -> Maybe String
+findValIns k = findVal ((== k) . toLower)
+
+trimQuotes :: String -> String
+trimQuotes = trimWith (\x -> x == '"' || x == ' ')