{-# LANGUAGE Rank2Types #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE NoMonomorphismRestriction #-}
{-# LANGUAGE TupleSections #-}
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE ImplicitParams #-}
{-# LANGUAGE ConstraintKinds #-}
{-# LANGUAGE TypeFamilies #-}

module Web.Apiary.Cookie 
    ( -- * setter
      setCookie
    , deleteCookie
    -- * filter
    , cookie
    , cookie'
    -- * Reexport
    -- | SetCookie(..)
    , module Web.Cookie
    ) where

import Web.Apiary.Wai
import Web.Apiary
import Web.Cookie (SetCookie(..))
import qualified Web.Cookie as Cookie

import Data.Apiary.Param
import Control.Monad.Apiary.Filter

import Data.Maybe
import Data.Time
import Data.Monoid
import Data.Apiary.Compat
import Blaze.ByteString.Builder
import Text.Blaze.Html
import qualified Data.ByteString as S
import qualified Data.ByteString.Char8 as SC

cond :: (a -> Bool) -> (a -> b) -> (a -> b) -> a -> b
cond p t f a = if p a then t a else f a

-- | cookie filter. since 0.5.1.0.
--
-- can use like 'query' function.
--
-- example:
--
-- @
-- cookie "foo" (pFirst pInt)  -- get first Int parameter from foo.
-- cookie "bar" (pOption pDouble)  -- get first Double parameter from bar, allows no cookie.
-- cookie "baz" (pMany (pMaybe pString))  -- get zero or more baz cookies. allows cookie decrypt failure.
-- cookie "baz" (Proxy :: Proxy (LimitSome [int|100|] ByteString)) -- get raw cookies up to 100 entries.
-- @
cookie :: (Strategy w, Monad actM, NotMember k prms, KnownSymbol k)
       => proxy k
       -> w S.ByteString
       -> ApiaryT exts (SNext w k S.ByteString prms) actM m ()
       -> ApiaryT exts prms actM m ()
cookie k p = function (DocPrecondition $ toHtml (symbolVal k) <> " cookie required") $ \l r ->
    strategy p k (map (Just . snd) . filter ((SC.pack (symbolVal k) ==) . fst) $ cookie' r) l

cookie' :: Request -> [(S.ByteString, S.ByteString)]
cookie' = 
    concatMap Cookie.parseCookies .
    mapMaybe (cond (("cookie" ==) . fst) (Just . snd) (const Nothing)) .
    requestHeaders

-- | delete cookie. since 0.6.1.0.
deleteCookie :: Monad m => S.ByteString -> ActionT exts prms m ()
deleteCookie k = setCookie def { setCookieName    = k 
                               , setCookieExpires = Just $ UTCTime (ModifiedJulianDay 0) 0
                               , setCookieMaxAge  = Just 0
                               }

-- | set raw cookie header.
setCookie :: Monad m => SetCookie -> ActionT exts prms m ()
setCookie =
    addHeader "set-cookie" . toByteString . Cookie.renderSetCookie