{-# LANGUAGE OverloadedStrings #-}
module Network.HTTP.Server.Mini.Printer where

import Data.ByteString (ByteString)
import Data.ByteString qualified as BS
import Data.ByteString.Lazy qualified as BSL
import Data.ByteString.Builder qualified as BSB
import Network.Socket
import Network.Socket.ByteString

import Network.HTTP.Server.Mini.Types


sendResponse :: Socket -> Response -> IO ()
sendResponse conn (Response status hdrs (BodyLBS body)) =
  sendResponseChunks conn status hdrs body
sendResponse conn (Response status hdrs (BodyFile path)) =
  -- lazy IO is fine here because the whole thing is traversed before the end of this function in sendMany
  sendResponseChunks conn status hdrs =<< BSL.readFile path

sendResponseChunks :: Socket -> Status -> [(Header, ByteString)] -> BSL.ByteString -> IO ()
sendResponseChunks conn (Status code reason) hdrs body =
  sendMany conn $
    BSL.toStrict (BSB.toLazyByteString
      (BSB.shortByteString "HTTP/1.1 "
       <> BSB.intDec code
       <> BSB.char8 ' '
       <> BSB.shortByteString reason
       <> BSB.shortByteString "\r\n"
       <> foldMap (\(key, val) ->
                    BSB.shortByteString key <> BSB.shortByteString ": "
                    <> BSB.byteString (wrapHdrVal val) <> BSB.shortByteString "\r\n")
                  hdrs
       <> BSB.shortByteString "Content-Length: " <> BSB.int64Dec (BSL.length body)
       <> BSB.shortByteString "\r\nConnection: close\r\n\r\n"))
    : BSL.toChunks body

wrapHdrVal :: ByteString -> ByteString
wrapHdrVal bs = BS.intercalate (BS.singleton 32) (BS.split 10 bs)