--- |Utility functions used internally in the Lucu httpd. These
--- functions may be useful too for something else.
+{-# LANGUAGE
+ OverloadedStrings
+ , RecordWildCards
+ , TemplateHaskell
+ , UnicodeSyntax
+ #-}
+-- |Utility functions used internally in this package.
module Network.HTTP.Lucu.Utils
( splitBy
- , joinWith
- , trim
- , noCaseEq
- , isWhiteSpace
, quoteStr
+ , parseWWWFormURLEncoded
+ , splitPathInfo
+ , trim
+
+ , getLastModified
+
+ , liftByteString
+ , liftLazyByteString
+ , liftAscii
+ , liftCIAscii
+ , liftText
+ , liftMap
+ , liftUTCTime
)
where
-
-import Control.Monad.Trans
+import Control.Applicative
+import Control.Monad
+import Data.Ascii (Ascii, CIAscii, AsciiBuilder)
+import qualified Data.Ascii as A
+import Data.ByteString (ByteString)
+import qualified Data.ByteString.Char8 as Strict
+import qualified Data.ByteString.Lazy.Internal as Lazy
import Data.Char
-import Data.List
-import Foreign
-import Foreign.C
+import Data.List hiding (last)
+import Data.Map (Map)
+import qualified Data.Map as M
+import Data.Monoid.Unicode
+import Data.Ratio
+import Data.Text (Text)
+import qualified Data.Text as T
+import Data.Time
+import Data.Time.Clock.POSIX
+import Language.Haskell.TH.Lib
+import Language.Haskell.TH.Syntax
import Network.URI
+import Prelude hiding (last)
+import Prelude.Unicode
+import System.Directory
+import System.Time (ClockTime(..))
+
+-- |>>> splitBy (== ':') "ab:c:def"
+-- ["ab", "c", "def"]
+splitBy ∷ (a → Bool) → [a] → [[a]]
+{-# INLINEABLE splitBy #-}
+splitBy isSep src
+ = case break isSep src of
+ (last , [] ) → [last]
+ (first, _sep:rest) → first : splitBy isSep rest
--- |> splitBy (== ':') "ab:c:def"
--- > ==> ["ab", "c", "def"]
-splitBy :: (a -> Bool) -> [a] -> [[a]]
-splitBy isSeparator src
- = case break isSeparator src
- of (last , [] ) -> last : []
- (first, sep:rest) -> first : splitBy isSeparator rest
-
--- |> joinWith ':' ["ab", "c", "def"]
--- > ==> "ab:c:def"
-joinWith :: [a] -> [[a]] -> [a]
-joinWith separator xs
- = foldr (++) [] $ intersperse separator xs
-
--- |> trim (== '_') "__ab_c__def___"
--- > ==> "ab_c__def"
-trim :: (a -> Bool) -> [a] -> [a]
-trim p = trimTail . trimHead
- where
- trimHead = dropWhile p
- trimTail = reverse . trimHead . reverse
-
--- |@'noCaseEq' a b@ is equivalent to @(map toLower a) == (map toLower
--- b)@
-noCaseEq :: String -> String -> Bool
-noCaseEq a b
- = (map toLower a) == (map toLower b)
-
--- |@'isWhiteSpace' c@ is True iff c is one of SP, HT, CR and LF.
-isWhiteSpace :: Char -> Bool
-isWhiteSpace = flip elem " \t\r\n"
-
--- |> quoteStr "abc"
--- > ==> "\"abc\""
+-- |>>> quoteStr "abc"
+-- "\"abc\""
--
--- > quoteStr "ab\"c"
--- > ==> "\"ab\\\"c\""
-quoteStr :: String -> String
-quoteStr str = foldr (++) "" (["\""] ++ map quote str ++ ["\""])
- where
- quote :: Char -> String
- quote '"' = "\\\""
- quote c = [c]
\ No newline at end of file
+-- >>> quoteStr "ab\"c"
+-- "\"ab\\\"c\""
+quoteStr ∷ Ascii → AsciiBuilder
+quoteStr str = A.toAsciiBuilder "\"" ⊕
+ go (A.toByteString str) (∅) ⊕
+ A.toAsciiBuilder "\""
+ where
+ go ∷ Strict.ByteString → AsciiBuilder → AsciiBuilder
+ go bs ab
+ = case Strict.break (≡ '"') bs of
+ (x, y)
+ | Strict.null y
+ → ab ⊕ b2ab x
+ | otherwise
+ → go (Strict.tail y)
+ (ab ⊕ b2ab x ⊕ A.toAsciiBuilder "\\\"")
+
+ b2ab ∷ Strict.ByteString → AsciiBuilder
+ b2ab = A.toAsciiBuilder ∘ A.unsafeFromByteString
+
+-- |>>> parseWWWFormURLEncoded "aaa=bbb&ccc=ddd"
+-- [("aaa", "bbb"), ("ccc", "ddd")]
+parseWWWFormURLEncoded ∷ Ascii → [(ByteString, ByteString)]
+parseWWWFormURLEncoded src
+ -- THINKME: We could gain some performance by using attoparsec
+ -- here.
+ | src ≡ "" = []
+ | otherwise = do pairStr ← splitBy (\ c → c ≡ ';' ∨ c ≡ '&') (A.toString src)
+ let (key, value) = break (≡ '=') pairStr
+ return ( unescape key
+ , unescape $ case value of
+ ('=':val) → val
+ val → val
+ )
+ where
+ unescape ∷ String → ByteString
+ unescape = Strict.pack ∘ unEscapeString ∘ map plusToSpace
+
+ plusToSpace ∷ Char → Char
+ plusToSpace '+' = ' '
+ plusToSpace c = c
+
+-- |>>> splitPathInfo "http://example.com/foo/bar"
+-- ["foo", "bar"]
+splitPathInfo ∷ URI → [ByteString]
+splitPathInfo uri
+ = let reqPathStr = uriPath uri
+ reqPath = [unEscapeString x | x ← splitBy (≡ '/') reqPathStr, (¬) (null x)]
+ in
+ map Strict.pack reqPath
+
+-- |>>> trim " ab c d "
+-- "ab c d"
+trim ∷ String → String
+trim = reverse ∘ f ∘ reverse ∘ f
+ where
+ f = dropWhile isSpace
+
+-- |Get the modification time of a given file.
+getLastModified ∷ FilePath → IO UTCTime
+getLastModified = (clockTimeToUTC <$>) ∘ getModificationTime
+ where
+ clockTimeToUTC ∷ ClockTime → UTCTime
+ clockTimeToUTC (TOD sec picoSec)
+ = posixSecondsToUTCTime
+ $ fromRational
+ $ sec % 1 + picoSec % (1000 ⋅ 1000 ⋅ 1000 ⋅ 1000)
+
+-- |Convert a 'ByteString' to an 'Exp' representing it as a literal.
+liftByteString ∷ ByteString → Q Exp
+liftByteString bs
+ = [| Strict.pack $(litE $ stringL $ Strict.unpack bs) |]
+
+-- |Convert a 'Lazy.ByteString' to an 'Exp' representing it as a
+-- literal.
+liftLazyByteString ∷ Lazy.ByteString → Q Exp
+liftLazyByteString = Lazy.foldrChunks f [| Lazy.Empty |]
+ where
+ f ∷ ByteString → Q Exp → Q Exp
+ f bs e = [| Lazy.Chunk $(liftByteString bs) $e |]
+
+-- |Convert an 'Ascii' to an 'Exp' representing it as a literal.
+liftAscii ∷ Ascii → Q Exp
+liftAscii a = [| A.unsafeFromByteString $(liftByteString $ A.toByteString a) |]
+
+-- |Convert a 'CIAscii' to an 'Exp' representing it as a literal.
+liftCIAscii ∷ CIAscii → Q Exp
+liftCIAscii a = [| A.toCIAscii $(liftAscii $ A.fromCIAscii a) |]
+
+-- |Convert a 'Text' to an 'Exp' representing it as a literal.
+liftText ∷ Text → Q Exp
+liftText t = [| T.pack $(litE $ stringL $ T.unpack t) |]
+
+-- |Convert an arbitrary 'Map' to an 'Exp' representing it as a
+-- literal, using a given key lifter and a value lifter.
+liftMap ∷ Eq k ⇒ (k → Q Exp) → (v → Q Exp) → Map k v → Q Exp
+liftMap liftK liftV m
+ | M.null m = [| M.empty |]
+ | otherwise = [| M.fromDistinctAscList $(liftPairs (M.toAscList m)) |]
+ where
+ liftPairs = listE ∘ map liftPair
+ liftPair (k, v) = tupE [liftK k, liftV v]
+
+-- |Convert an 'UTCTime' to an 'Exp' representing it as a literal.
+liftUTCTime ∷ UTCTime → Q Exp
+liftUTCTime (UTCTime {..})
+ = [| UTCTime $(liftDay utctDay) $(liftDiffTime utctDayTime) |]
+
+liftDay ∷ Day → Q Exp
+liftDay (ModifiedJulianDay {..})
+ = [| ModifiedJulianDay $(lift toModifiedJulianDay) |]
+
+liftDiffTime ∷ DiffTime → Q Exp
+liftDiffTime dt = [| fromRational ($n % $d) ∷ DiffTime |]
+ where
+ n, d ∷ Q Exp
+ n = lift $ numerator $ toRational dt
+ d = lift $ denominator $ toRational dt