Better name-rewriting engine

[Lucu.git] / Network / HTTP / Lucu / Headers.hs

diff --git a/Network/HTTP/Lucu/Headers.hs b/Network/HTTP/Lucu/Headers.hs
index fbab8563852c1efc56e6bab72006257934340938..80b9b1339501d95a08c80511645e3603a5b1d9ea 100644 (file)
--- a/Network/HTTP/Lucu/Headers.hs
+++ b/Network/HTTP/Lucu/Headers.hs
@@ -1,45 +1,158 @@
+{-# LANGUAGE
+    GeneralizedNewtypeDeriving
+  , OverloadedStrings
+  , UnicodeSyntax
+  #-}
+-- |An internal module for HTTP headers.
 module Network.HTTP.Lucu.Headers
     ( Headers
     , HasHeaders(..)
-    , emptyHeaders   -- Headers
+
+    , singleton
+
+    , toHeaders
+    , fromHeaders
+
+    , headers
+    , printHeaders
     )
     where
+import Control.Applicative
+import Control.Monad
+import Data.Ascii (Ascii, AsciiBuilder, CIAscii)
+import qualified Data.Ascii as A
+import Data.Attoparsec.Char8 as P
+import qualified Data.ByteString as BS
+import Data.List
+import Data.Map (Map)
+import qualified Data.Map as M
+import qualified Data.Map.Unicode as M
+import Data.Monoid
+import Data.Monoid.Unicode
+import Network.HTTP.Lucu.Parser.Http
+import Prelude.Unicode
 
-import qualified Data.ByteString.Lazy.Char8 as B
-import           Data.ByteString.Lazy.Char8 (ByteString)
-import           Data.Char
-import           Data.List
-
-type Headers = [ (ByteString, ByteString) ]
+newtype Headers
+    = Headers (Map CIAscii Ascii)
+      deriving (Eq, Show, Monoid)
 
 class HasHeaders a where
-    getHeaders :: a -> Headers
-    setHeaders :: a -> Headers -> a
+    getHeaders ∷ a → Headers
+    setHeaders ∷ a → Headers → a
+
+    getHeader ∷ CIAscii → a → Maybe Ascii
+    getHeader key a
+        = case getHeaders a of
+            Headers m → M.lookup key m
+
+    hasHeader ∷ CIAscii → a → Bool
+    {-# INLINE hasHeader #-}
+    hasHeader key a
+        = case getHeaders a of
+            Headers m → key M.∈ m
+
+    getCIHeader ∷ CIAscii → a → Maybe CIAscii
+    {-# INLINE getCIHeader #-}
+    getCIHeader key a
+        = A.toCIAscii <$> getHeader key a
+
+    deleteHeader ∷ CIAscii → a → a
+    {-# INLINE deleteHeader #-}
+    deleteHeader key a
+        = case getHeaders a of
+            Headers m
+              → setHeaders a $ Headers $ M.delete key m
 
-    getHeader :: a -> ByteString -> Maybe ByteString
-    getHeader a key
-        = fmap snd $ find (noCaseEq key . fst) (getHeaders a)
+    setHeader ∷ CIAscii → Ascii → a → a
+    {-# INLINE setHeader #-}
+    setHeader key val a
+        = case getHeaders a of
+            Headers m
+              → setHeaders a $ Headers $ M.insert key val m
 
-    deleteHeader :: a -> ByteString -> a
-    deleteHeader a key
-        = setHeaders a $ filter (not . noCaseEq key . fst) (getHeaders a)
+instance HasHeaders Headers where
+    getHeaders   = id
+    setHeaders _ = id
 
-    addHeader :: a -> ByteString -> ByteString -> a
-    addHeader a key val
-        = setHeaders a $ (getHeaders a) ++ [(key, val)]
+singleton ∷ CIAscii → Ascii → Headers
+{-# INLINE singleton #-}
+singleton key val
+    = Headers $ M.singleton key val
 
-    setHeader :: a -> ByteString -> ByteString -> a
-    setHeader a key val
-        = let list    = getHeaders a
-              deleted = filter (not . noCaseEq key . fst) list
-              added   = deleted ++ [(key, val)]
-          in 
-            setHeaders a added
+toHeaders ∷ [(CIAscii, Ascii)] → Headers
+{-# INLINE toHeaders #-}
+toHeaders = flip mkHeaders (∅)
 
-noCaseEq :: ByteString -> ByteString -> Bool
-noCaseEq a b
-    = (B.map toLower a) == (B.map toLower b)
+mkHeaders ∷ [(CIAscii, Ascii)] → Headers → Headers
+mkHeaders []              (Headers m) = Headers m
+mkHeaders ((key, val):xs) (Headers m)
+    = mkHeaders xs $ Headers $
+      case M.lookup key m of
+        Nothing  → M.insert key val m
+        Just old → M.insert key (merge old val) m
+    where
+      merge ∷ Ascii → Ascii → Ascii
+      {-# INLINE merge #-}
+      merge a b
+          | nullA a ∧ nullA b = (∅)
+          | nullA a           = b
+          |           nullA b = a
+          | otherwise         = a ⊕ ", " ⊕ b
+
+      nullA ∷ Ascii → Bool
+      {-# INLINE nullA #-}
+      nullA = BS.null ∘ A.toByteString
+
+fromHeaders ∷ Headers → [(CIAscii, Ascii)]
+fromHeaders (Headers m) = M.toList m
+
+{-
+  message-header = field-name ":" [ field-value ]
+  field-name     = token
+  field-value    = *( field-content | LWS )
+  field-content  = <field-value を構成し、*TEXT あるいは
+                    token, separators, quoted-string を連結
+                    したものから成る OCTET>
 
+  field-value の先頭および末尾にある LWS は全て削除され、それ以外の
+  LWS は單一の SP に變換される。
+-}
+headers ∷ Parser Headers
+{-# INLINEABLE headers #-}
+headers = do xs ← P.many header
+             crlf
+             return $ toHeaders xs
+    where
+      header ∷ Parser (CIAscii, Ascii)
+      header = do name ← A.toCIAscii <$> token
+                  void $ char ':'
+                  skipMany lws
+                  values ← content `sepBy` try lws
+                  skipMany (try lws)
+                  crlf
+                  return (name, joinValues values)
+
+      content ∷ Parser Ascii
+      {-# INLINE content #-}
+      content = A.unsafeFromByteString
+                <$>
+                takeWhile1 (\c → isText c ∧ c ≢ '\x20')
 
-emptyHeaders :: Headers
-emptyHeaders = []
\ No newline at end of file
+      joinValues ∷ [Ascii] → Ascii
+      {-# INLINE joinValues #-}
+      joinValues = A.fromAsciiBuilder
+                   ∘ mconcat
+                   ∘ intersperse (A.toAsciiBuilder "\x20")
+                   ∘ map A.toAsciiBuilder
+
+printHeaders ∷ Headers → AsciiBuilder
+printHeaders (Headers m)
+    = mconcat (map printHeader (M.toList m)) ⊕
+      A.toAsciiBuilder "\x0D\x0A"
+    where
+      printHeader ∷ (CIAscii, Ascii) → AsciiBuilder
+      printHeader (name, value)
+          = A.toAsciiBuilder (A.fromCIAscii name) ⊕
+            A.toAsciiBuilder ": "                 ⊕
+            A.toAsciiBuilder value                ⊕
+            A.toAsciiBuilder "\x0D\x0A"