X-Git-Url: http://git.cielonegro.org/gitweb.cgi?p=Lucu.git;a=blobdiff_plain;f=Network%2FHTTP%2FLucu%2FMIMEType%2FGuess.hs;h=05d0cd606f383eccdbef688a39dfa4f1e215b3d5;hp=2664d79b859e853565090f5581e103e7f9fce17f;hb=90fca0675b1694e69b8e431c989343855cbd125d;hpb=6126eb9cbe5b38c300d855d96d2238831e59b5dd

diff --git a/Network/HTTP/Lucu/MIMEType/Guess.hs b/Network/HTTP/Lucu/MIMEType/Guess.hs
index 2664d79..05d0cd6 100644
--- a/Network/HTTP/Lucu/MIMEType/Guess.hs
+++ b/Network/HTTP/Lucu/MIMEType/Guess.hs
@@ -1,138 +1,144 @@
 {-# LANGUAGE
-    UnicodeSyntax
+    DeriveDataTypeable
+  , GeneralizedNewtypeDeriving
+  , MultiParamTypeClasses
+  , TemplateHaskell
+  , UnicodeSyntax
+  , ViewPatterns
   #-}
--- |MIME Type guessing by a file extension. This is a poor man's way
--- of guessing MIME Types. It is simple and fast.
+-- |Guessing MIME Types by file extensions. It's not always accurate
+-- but simple and fast.
 --
 -- In general you don't have to use this module directly.
 module Network.HTTP.Lucu.MIMEType.Guess
-    ( ExtMap
+    ( ExtMap(..)
+    , extMap
     , guessTypeByFileName
-
-    , parseExtMapFile
-    , serializeExtMap
     )
     where
 import Control.Applicative
-import qualified Data.Ascii as A
-import Data.Attoparsec.Char8 as P
+import Data.Attoparsec.Char8
 import qualified Data.Attoparsec.Lazy as LP
-import qualified Data.ByteString.Lazy.Char8 as B
+import qualified Data.ByteString.Lazy.Char8 as Lazy
+import Data.Convertible.Base
+import Data.Convertible.Instances.Text ()
+import Data.Default
 import qualified Data.Map as M
 import Data.Map (Map)
-import Data.Maybe
+import Data.Typeable
+import Data.List
+import Data.Monoid
+import Data.Monoid.Unicode
 import Data.Text (Text)
-import qualified Data.Text as T
 import Data.Text.Encoding
-import Language.Haskell.Exts.Build
-import Language.Haskell.Exts.Extension
-import Language.Haskell.Exts.Pretty
-import Language.Haskell.Exts.Syntax
+import Language.Haskell.TH.Syntax
+import Language.Haskell.TH.Quote
 import Network.HTTP.Lucu.MIMEType
+import Network.HTTP.Lucu.OrphanInstances ()
+import Network.HTTP.Lucu.Parser
 import Prelude.Unicode
 import System.FilePath
 
--- |'Map' from extension to 'MIMEType'.
-type ExtMap = Map Text MIMEType
-
--- |Guess the MIME Type of file.
-guessTypeByFileName ∷ ExtMap → FilePath → Maybe MIMEType
-guessTypeByFileName extMap fpath
-    = let ext = T.pack $ takeExtension fpath
-      in
-        M.lookup ext extMap
+-- |A 'Map' from file extensions to 'MIMEType's.
+newtype ExtMap
+    = ExtMap (Map Text MIMEType)
+    deriving (Eq, Show, Read, Monoid, Typeable)
 
--- |Read an Apache mime.types and parse it.
-parseExtMapFile ∷ FilePath → IO ExtMap
-parseExtMapFile fpath
-    = do file ← B.readFile fpath
-         case LP.parse extMapP file of
-           LP.Done _ xs  → return $ compile xs
-           LP.Fail _ _ e → fail ("Failed to parse: " ⧺ fpath ⧺ ": " ⧺ e)
+instance Lift ExtMap where
+    lift (ExtMap m) = [| ExtMap $(lift m) |]
 
-extMapP ∷ Parser [ (MIMEType, [Text]) ]
-extMapP = do xs ← P.many (comment <|> validLine <|> emptyLine)
-             endOfInput
-             return $ catMaybes xs
+-- |'QuasiQuoter' for 'ExtMap' reading Apache @mime.types@.
+--
+-- @
+--   m :: 'ExtMap'
+--   m = ['extMap'|
+--   # MIME Type            Extensions
+--   application/xhtml+xml  xhtml
+--   image/jpeg             jpeg jpg
+--   image/png              png
+--   image/svg+xml          svg
+--   text/html              html
+--   text/plain             txt
+--   |]
+-- @
+extMap ∷ QuasiQuoter
+extMap = QuasiQuoter {
+             quoteExp  = lift ∘ parseExtMap ∘ Lazy.pack
+           , quotePat  = const unsupported
+           , quoteType = const unsupported
+           , quoteDec  = const unsupported
+         }
     where
-      isSpc ∷ Char → Bool
-      isSpc c = c ≡ '\x20' ∨ c ≡ '\x09'
+      parseExtMap ∷ Lazy.ByteString → ExtMap
+      parseExtMap = convertUnsafe
 
-      comment ∷ Parser (Maybe (MIMEType, [Text]))
-      comment = try $
-                do skipWhile isSpc
-                   _ ← char '#'
-                   skipWhile (≢ '\x0A')
-                   return Nothing
+      unsupported ∷ Monad m ⇒ m α
+      unsupported = fail "Unsupported usage of extMap quasi-quoter."
 
-      validLine ∷ Parser (Maybe (MIMEType, [Text]))
-      validLine = try $
-                  do skipWhile isSpc
-                     mime ← mimeTypeP
-                     skipWhile isSpc
-                     exts ← sepBy extP (skipWhile isSpc)
-                     return $ Just (mime, exts)
+instance ConvertAttempt Lazy.ByteString ExtMap where
+    convertAttempt src
+        = case LP.parse pairs src of
+            LP.Fail _ eCtx e
+                → fail $ "Unparsable extension map: "
+                       ⊕ intercalate ", " eCtx
+                       ⊕ ": "
+                       ⊕ e
+            LP.Done _ xs
+                → case compile xs of
+                     Right m → return $ ExtMap m
+                     Left  e → fail $ "Duplicate extension: " ⊕ show e
+        where
+          pairs ∷ Parser [(MIMEType, [Text])]
+          pairs = do skipMany linebreak
+                     xs ← sepBy pair (skipMany1 linebreak)
+                     skipMany linebreak
+                     endOfInput
+                     return xs
+                  <?>
+                  "pairs"
 
-      extP ∷ Parser Text
-      extP = decodeUtf8 <$> takeWhile1 (\c → (¬) (isSpc c ∨ c ≡ '\x0A'))
+          pair ∷ Parser (MIMEType, [Text])
+          pair = do skipSpace
+                    mime ← def
+                    skipSpace1
+                    exts ← sepBy1 ext $ skipWhile1 (≡ '\x20')
+                    return (mime, exts)
+                 <?>
+                 "pair"
 
-      emptyLine ∷ Parser (Maybe (MIMEType, [Text]))
-      emptyLine = try $
-                  do skipWhile isSpc
-                     _ ← char '\x0A'
-                     return Nothing
+          ext ∷ Parser Text
+          ext = (decodeUtf8 <$> takeWhile1 isAlphaNum)
+                <?>
+                "ext"
 
-compile ∷ [ (MIMEType, [Text]) ] → Map Text MIMEType
-compile = M.fromList ∘ concat ∘ map tr
-    where
-      tr ∷ (MIMEType, [Text]) → [ (Text, MIMEType) ]
-      tr (mime, exts) = [ (ext, mime) | ext ← exts ]
+          linebreak ∷ Parser ()
+          linebreak
+              = ( endOfLine
+                  <|>
+                  try (skipSpace *> char '#' *> skipManyTill anyChar endOfLine)
+                )
+                <?>
+                "linebreak"
 
--- |@'serializeExtMap' extMap moduleName variableName@ generates a
--- Haskell source code which contains the following things:
---
--- * A definition of module named @moduleName@.
---
--- * @variableName :: 'ExtMap'@ whose content is a serialization of
---   @extMap@.
---
--- The module "Network.HTTP.Lucu.MIMEType.DefaultExtensionMap" is
--- surely generated using this function.
-serializeExtMap ∷ ExtMap → String → String → String
-serializeExtMap extMap moduleName variableName
-    = let hsModule  = Module (⊥) (ModuleName moduleName) modPragma
-                      Nothing (Just exports) imports decls
-          modPragma = [ LanguagePragma (⊥) [ name (show OverloadedStrings) ] ]
-          exports   = [ EVar (UnQual (name variableName)) ]
-          imports   = [ ImportDecl (⊥) (ModuleName "Network.HTTP.Lucu.MIMEType")
-                                   False False Nothing Nothing Nothing
-                      , ImportDecl (⊥) (ModuleName "Network.HTTP.Lucu.MIMEType.Guess")
-                                   False False Nothing Nothing Nothing
-                      , ImportDecl (⊥) (ModuleName "Data.Ascii")
-                                   False False Nothing Nothing (Just (False, []))
-                      , ImportDecl (⊥) (ModuleName "Data.Map")
-                                   True False Nothing (Just (ModuleName "M")) Nothing
-                      ]
-          decls     = [ TypeSig (⊥) [name variableName]
-                                    (TyCon (UnQual (name "ExtMap")))
-                      , nameBind (⊥) (name variableName) extMapExp
-                      ]
-          comment   = concat [ "{- !!! WARNING !!!\n"
-                             , "   This file is automatically generated.\n"
-                             , "   DO NOT EDIT BY HAND OR YOU WILL REGRET -}\n\n"
-                             ]
-          extMapExp = qvar (ModuleName "M") (name "fromList") `app` listE records
-      in
-        comment ⧺ prettyPrint hsModule ⧺ "\n"
+compile ∷ Ord k ⇒ [(v, [k])] → Either (k, v, v) (Map k v)
+compile = go (∅) ∘ concat ∘ (tr <$>)
     where
-      records ∷ [Exp]
-      records = map record $ M.assocs extMap
+      tr ∷ (v, [k]) → [(k, v)]
+      tr (v, ks) = [(k, v) | k ← ks]
 
-      record ∷ (Text, MIMEType) → Exp
-      record (ext, mime)
-          = tuple [ strE (T.unpack ext)
-                  , metaFunction "parseMIMEType" [strE $ mimeToString mime]
-                  ]
+      go ∷ Ord k ⇒ Map k v → [(k, v)] → Either (k, v, v) (Map k v)
+      go m []         = Right m
+      go m ((k, v):xs)
+          = case M.insertLookupWithKey' f k v m of
+              (Nothing, m') → go m' xs
+              (Just v0, _ ) → Left (k, v0, v)
 
-      mimeToString ∷ MIMEType → String
-      mimeToString = A.toString ∘ A.fromAsciiBuilder ∘ printMIMEType
+      f ∷ k → v → v → v
+      f _ _ = id
+
+-- |Guess the MIME Type of a file.
+guessTypeByFileName ∷ ExtMap → FilePath → Maybe MIMEType
+guessTypeByFileName (ExtMap m) fpath
+    = case takeExtension fpath of
+        []      → Nothing
+        (_:ext) → M.lookup (cs ext) m