{-# LANGUAGE NoImplicitPrelude #-}

module RFC.Wai
  ( defaultMiddleware
  , module Network.Wai
  ) where

import           Network.HTTP.Types.Header
import           Network.HTTP.Types.Method
import           Network.Wai
import           Network.Wai.Middleware.AcceptOverride
import           Network.Wai.Middleware.Approot            ( envFallback )
import           Network.Wai.Middleware.Autohead
import           Network.Wai.Middleware.Cors
import           Network.Wai.Middleware.Gzip
import           Network.Wai.Middleware.Jsonp
import           Network.Wai.Middleware.MethodOverridePost
import           Network.Wai.Middleware.RequestLogger      ( logStdout, logStdoutDev )
import           RFC.Env                                   ( isDevelopment )
import           RFC.Prelude
import           System.IO.Temp
  ( createTempDirectory, getCanonicalTemporaryDirectory )

defaultMiddleware :: IO Middleware
defaultMiddleware = do
  isDev <- isDevelopment
  approot <- envFallback
  tmpDir <- getCanonicalTemporaryDirectory
  gzipDir <- createTempDirectory tmpDir "wai-gzip-middleware"
  return $
    methodOverridePost .
    acceptOverride .
    (cors $ const $ Just corsConfig).
    autohead .
    jsonp .
    approot .
    gzip (gzipConfig gzipDir) .
    (if isDev then logStdoutDev else logStdout)
  where
    corsConfig = simpleCorsResourcePolicy
      { corsRequireOrigin = False
      , corsVaryOrigin = False
      , corsMaxAge = Nothing
      , corsRequestHeaders = hContentType : simpleHeaders
      , corsMethods =
        [ methodGet
        , methodPost
        , methodHead
        , methodDelete
        , methodPatch
        , methodOptions
        , methodPut
        ]
      }
    gzipConfig gzipDir = def
      { gzipFiles = GzipCacheFolder gzipDir
      , gzipCheckMime = const True
      }