module Login where

import Prelude (Unit, bind, not, pure, show, unit, ($), (&&), (<$>), (=<<), discard)
import Control.Monad.Aff (runAff)
import Control.Monad.Eff (Eff)
import Control.Monad.Eff.Console (CONSOLE, log)
import Control.Monad.Eff.JQuery (JQuery, JQueryEvent, display, getValue, hide, on, preventDefault, ready, select, setProp)

import DOM (DOM)

import Data.Function.Uncurried (runFn2)
import Data.Maybe (Maybe(..), fromJust, isNothing)
import Data.Either (Either(..), either)
import Data.Tuple (Tuple(..))

import Data.Argonaut as A
import Data.Argonaut.Decode (decodeJson)

import Network.HTTP.Affjax (AJAX, post)

import Data.FormURLEncoded as UE

import Partial.Unsafe (unsafePartial)

import Common (Challenge(..), Elem(..), Err(..), fail, fromForeign, fromHex, fromUtf8, hmacSha3, progress, welcome, getAttr)

-- main :: forall e. Eff (console :: CONSOLE | e) Unit
-- main = do
--   log "Hello sailor!"

-- main :: forall eff. Eff ( ajax :: AJAX
--                         , dom :: DOM
--                         , console :: CONSOLE
--                         | eff
--                         ) Unit
-- main =
--   ready $ do
--     log "logging in"
--     display =<< select ".js-hidden"
--     hide =<< select ".noscript"
--     login <- select "#login"
--     on "click" (onLoginClick login) login

onLoginClick
  :: forall eff. JQuery
  -> JQueryEvent
  -> JQuery
  -> Eff ( dom :: DOM
    , console :: CONSOLE
    , ajax :: AJAX
    | eff
    ) Unit
onLoginClick login ev x = unsafePartial $ do
  log "click!"
  preventDefault ev
  hide login
  _ <- setProp "disabled" true <$> select ".login input"
  fusername <- getValue =<< select "#username"
  fpassword <- getValue =<< select "#password"
  formAction <- getAttr "action" =<< select "#loginform"
  log formAction
  let username = fromForeign fusername
      password = fromForeign fpassword
  if not (isNothing username && isNothing password)
    then do
      progress "Obtaining Challenge..."
      let data1 = UE.fromArray $ [ Tuple "username" username ]
      _ <- runAff
          (\e -> fail Login $ show e)
          (\y -> resp1Success (fromJust password) y.response formAction)
          $ post formAction data1
      log "success so far"
    else
      log "error"

resp1Success :: forall eff. String
  -> A.Json
  -> String
  -> Eff ( dom :: DOM
    , console :: CONSOLE
    , ajax :: AJAX
    | eff
    ) Unit
resp1Success pass j loc = do
  log $ show j
  let eitherChallenge = decodeJson j
  case eitherChallenge of
    Left _ -> do
      let eitherErr = decodeJson j
      either (fail Login) (\(Err e) -> fail Login e.err) eitherErr
    Right (Challenge challenge) -> do
      progress "HMAC 1"
      let salted = runFn2 hmacSha3 (fromUtf8 pass) (fromHex challenge.salt)
      -- log $ "salted: " <> salted
      progress "HMAC 2"
      let response = runFn2 hmacSha3 (fromUtf8 salted) (fromUtf8 challenge.token)
      -- log $ "resp: " <> response
      progress "sending response"
      let data2 = UE.fromArray $ [ Tuple "token" (Just challenge.token), Tuple "response" (Just response) ]
      _ <- runAff
          (\e -> fail Login $ show e)
          (\x -> welcome x.response Login)
          $ post loc data2
      pure unit