module Main where

#ifndef ghcjs_HOST_OS
import Language.Javascript.JSaddle.Warp as JSaddle
#endif

import Data.ByteString.UTF8 qualified as B
import Data.Maybe
import Miso
import Miso.String

#ifndef ghcjs_HOST_OS
import Network.HTTP.Simple
import Data.String
#else
import JavaScript.Web.XMLHttpRequest
#endif

type Model = Maybe Schema

type Schema = String

data Action
  = FetchSchema
  | SetSchema Schema
  deriving (Show, Eq)

#ifndef ghcjs_HOST_OS
runApp :: JSM () -> IO ()
runApp f = JSaddle.debugOr 8080 (f >> syncPoint) JSaddle.jsaddleApp
#else
runApp :: IO () -> IO ()
runApp app = app
#endif

main :: IO ()
main = runApp $ startApp App {..}
  where
    initialAction = FetchSchema
    model = Nothing
    update = updateModel
    view = viewModel
    events = defaultEvents
    subs = []
    mountPoint = Nothing
    logLevel = Off

updateModel :: Action -> Model -> Effect Action Model
updateModel action m =
  case action of
    FetchSchema -> m <# do SetSchema <$> fetchSchema
    SetSchema schema -> noEff (Just schema)

fetchSchema :: JSM String
fetchSchema = fetch "http://localhost:8081/posts.schema.json"

#ifndef ghcjs_HOST_OS
fetch :: String -> JSM String
fetch url = B.toString . getResponseBody <$> httpBS (fromString url)
#else
fetch :: String -> JSM String
fetch url = maybe "" B.toString . contents <$> xhrByteString req
  where
    req =
      Request
        { reqMethod = GET,
          reqURI = pack url,
          reqLogin = Nothing,
          reqHeaders = [],
          reqWithCredentials = False,
          reqData = NoData
        }
#endif

viewModel :: Model -> View Action
viewModel schema =
  div_ [] [text (toMisoString (fromMaybe ".." schema))]