open Lwt.Syntax
open Js_of_ocaml

(* https://stackoverflow.com/questions/34929382/what-are-the-differences-between-lwt-async-and-lwt-main-run-on-ocaml-node-js *)
let rec run t =
  let next_tick (_callback : unit -> unit) =
    Js.Unsafe.(fun_call
                 (js_expr "process.nextTick")
                 [| inject (Js.wrap_callback _callback) |])
  in Lwt.wakeup_paused ();
     match Lwt.poll t with
     | Some x -> x
     | None ->
        if Lwt.paused_count () > 0
        then next_tick (fun () -> run t)
        else ()

let () =
  run @@
    let* server = Portal_ws.ws_endpoint "telepath.im" in
    let stream, push =
      (* Echo is a websocket that... echoes you stuff. *)
         Portal_ws.ws_stream "wss://echo.websocket.org" in
       push (Some "great text");
       push (Some "other text");
       push (Some "yet another text");
       push (Some "BYE");
       let+ _ = Lwt_stream.iter
               (fun greetings ->
                 match greetings with
                 (* When the websocket sends "BYE", we close. *)
                 | "BYE" -> print_endline "CLOSING BYE"; push None
                 | hello -> print_endline ("> " ^ hello))
               stream
       in print_endline server