Supplession of unneeded imports

[Lucu.git] / Network / HTTP / Lucu / MIMEType / Guess.hs

diff --git a/Network/HTTP/Lucu/MIMEType/Guess.hs b/Network/HTTP/Lucu/MIMEType/Guess.hs
index 309f7fe0621a427ca1fb1ed0bb1ec09e90e3acee..a0ea1646b4e8e3c29493e0e89743145db825b0c5 100644 (file)
--- a/Network/HTTP/Lucu/MIMEType/Guess.hs
+++ b/Network/HTTP/Lucu/MIMEType/Guess.hs
@@ -1,11 +1,17 @@
+-- |MIME Type guesser which guesses by a file extension. This is a
+-- poor man's way of guessing MIME Types. It is simple and fast.
+--
+-- In general you don't have to use this module directly.
 module Network.HTTP.Lucu.MIMEType.Guess
-    ( parseExtMapFile  -- FilePath -> IO (Map String MIMEType)
-    , outputExtMapAsHS -- Map String MIMEType -> FilePath -> IO ()
+    ( ExtMap
+    , guessTypeByFileName
+
+    , parseExtMapFile
+    , serializeExtMap
     )
     where
 
 import qualified Data.ByteString.Lazy.Char8 as B
-import           Data.ByteString.Lazy.Char8 (ByteString)
 import qualified Data.Map as M
 import           Data.Map (Map)
 import           Data.Maybe
@@ -14,13 +20,25 @@ import           Language.Haskell.Syntax
 import           Network.HTTP.Lucu.MIMEType
 import           Network.HTTP.Lucu.Parser
 import           Network.HTTP.Lucu.Parser.Http
+import           Network.HTTP.Lucu.Utils
 import           System.IO
 
-import Debug.Trace
+-- |Map from extension to MIME Type.
+type ExtMap = Map String MIMEType
+
+-- |Guess the MIME Type of file.
+guessTypeByFileName :: ExtMap -> FilePath -> Maybe MIMEType
+guessTypeByFileName extMap fpath
+    = extMap `seq` fpath `seq`
+      let ext = last $ splitBy (== '.') fpath
+      in
+        M.lookup ext extMap >>= return
 
-parseExtMapFile :: FilePath -> IO (Map String MIMEType)
+-- |Read an Apache mime.types and parse it.
+parseExtMapFile :: FilePath -> IO ExtMap
 parseExtMapFile fpath
-    = do file <- B.readFile fpath
+    = fpath `seq`
+      do file <- B.readFile fpath
          case parse (allowEOF extMapP) file of
            (Success xs, _) -> return $ compile xs
            (_, input')     -> let near = B.unpack $ B.take 100 input'
@@ -55,29 +73,37 @@ compile = M.fromList . foldr (++) [] . map tr
       tr :: (MIMEType, [String]) -> [ (String, MIMEType) ]
       tr (mime, exts) = [ (ext, mime) | ext <- exts ]
 
-
-outputExtMapAsHS :: Map String MIMEType -> FilePath -> IO ()
-outputExtMapAsHS extMap fpath
+-- |@'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 = HsModule undefined modName (Just exports) imports decls
-          modName  = Module "Network.HTTP.Lucu.MIMEType.DefaultExtensionMap"
-          exports  = [HsEVar (UnQual (HsIdent "defaultExtensionMap"))]
+          modName  = Module moduleName
+          exports  = [HsEVar (UnQual (HsIdent variableName))]
           imports  = [ HsImportDecl undefined (Module "Network.HTTP.Lucu.MIMEType") False Nothing Nothing
+                     , HsImportDecl undefined (Module "Network.HTTP.Lucu.MIMEType.Guess") False Nothing Nothing
                      , HsImportDecl undefined (Module "Data.Map") True (Just (Module "M")) Nothing
-                     , HsImportDecl undefined (Module "Data.Map") False Nothing (Just (False, [HsIAbs (HsIdent "Map")]))
                      ]
-          decls    = [ HsTypeSig undefined [HsIdent "defaultExtensionMap"]
-                                     (HsQualType [] (HsTyApp (HsTyApp (HsTyCon (UnQual (HsIdent "Map")))
-                                                                      (HsTyCon (UnQual (HsIdent "String"))))
-                                                             (HsTyCon (UnQual (HsIdent "MIMEType")))))
-                     , HsFunBind [HsMatch undefined (HsIdent "defaultExtensionMap")
+          decls    = [ HsTypeSig undefined [HsIdent variableName]
+                                     (HsQualType []
+                                      (HsTyCon (UnQual (HsIdent "ExtMap"))))
+                     , HsFunBind [HsMatch undefined (HsIdent variableName)
                                   [] (HsUnGuardedRhs extMapExp) []]
                      ]
           extMapExp = HsApp (HsVar (Qual (Module "M") (HsIdent "fromList"))) (HsList records)
           comment =    "{- !!! WARNING !!!\n"
-                    ++ "   This file is automatically generated from data/mime.types.\n"
+                    ++ "   This file is automatically generated.\n"
                     ++ "   DO NOT EDIT BY HAND OR YOU WILL REGRET -}\n\n"
       in
-        writeFile fpath $ comment ++ prettyPrint hsModule ++ "\n"
+        comment ++ prettyPrint hsModule ++ "\n"
     where
       records :: [HsExp]
       records = map record $ M.assocs extMap
@@ -90,16 +116,16 @@ outputExtMapAsHS extMap fpath
       mimeToExp (MIMEType maj min params)
           = foldl appendParam (HsInfixApp
                                (HsLit (HsString maj))
-                               (HsQVarOp (UnQual (HsSymbol "+/+")))
+                               (HsQVarOp (UnQual (HsSymbol "</>")))
                                (HsLit (HsString min))) params
 
       appendParam :: HsExp -> (String, String) -> HsExp
       appendParam x param
-          = HsInfixApp x (HsQVarOp (UnQual (HsSymbol "+:+"))) $ paramToExp param
+          = HsInfixApp x (HsQVarOp (UnQual (HsSymbol "<:>"))) $ paramToExp param
 
       paramToExp :: (String, String) -> HsExp
       paramToExp (name, value)
           = HsInfixApp
             (HsLit (HsString name))
-            (HsQVarOp (UnQual (HsSymbol "+=+")))
+            (HsQVarOp (UnQual (HsSymbol "<=>")))
             (HsLit (HsString value))
\ No newline at end of file