{-# LANGUAGE CPP #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE Strict #-}
module Main where

import Foreign.C.Types (CInt)
import qualified Network.HTTP.Types as HTTPTypes
import qualified Network.ServerStarter.Socket as Starter
import qualified Network.Socket as Socket
import qualified Network.Wai as Wai
import qualified Network.Wai.Handler.Warp as Warp


ioFdSocket :: Socket.Socket -> IO CInt
#if MIN_VERSION_network(3, 1, 0)
ioFdSocket = Socket.unsafeFdSocket
#else
ioFdSocket = return . Socket.fdSocket
#endif

app :: Wai.Application
app _ respond = do
  putStrLn "Got request"
  respond $ Wai.responseLBS
    HTTPTypes.status200
    [("Content-Type", "text/plain")]
    "Hello, Web!"

main :: IO ()
main = do
  (socket:_) <- Starter.listenAll
  print =<< ioFdSocket socket
  port <- flip fmap (Socket.getSocketName socket) $ \addr -> case addr of
    Socket.SockAddrInet p _ -> p
    Socket.SockAddrUnix _   -> 0
  print port
  let setting = Warp.setHTTP2Disabled
              . Warp.setPort (fromEnum port)
              $ Warp.defaultSettings
  Warp.runSettingsSocket setting socket app
  putStrLn "Finished an old server"
  return ()