module T = Opentelemetry
let spf = Printf.sprintf
let (let@) f x = f x

let run () =
  Printf.printf "collector is on %S\n%!" (Opentelemetry_client_ocurl.get_url());
  let i = ref 0 in
  while true do
    let@ scope = T.Trace.with_ ~kind:T.Span.Span_kind_producer
        "loop.outer" ~attrs:["i", `Int !i] in

    for j=0 to 4 do

      let@ scope = T.Trace.with_ ~kind:T.Span.Span_kind_internal
          ~trace_id:scope.trace_id ~parent:scope.span_id
          ~attrs:["j", `Int j]
          "loop.inner" in
      Unix.sleepf 2.;

      let gc = Gc.stat() in
      T.Metrics.(
        emit [
          gauge ~name:"ocaml_opentracing.test.i" [int !i];
          gauge ~name:"ocaml_opentracing.test.major_heap_words" [int gc.Gc.heap_words];
          sum ~name:"ocaml_opentracing.test.minor_allocated" [float gc.Gc.minor_words];
        ]);

      incr i;

      (try
        let@ _ =
          T.Trace.with_ ~kind:T.Span.Span_kind_internal
            ~trace_id:scope.trace_id ~parent:scope.span_id
            "alloc" in
        (* allocate some stuff *)
        let _arr = Sys.opaque_identity @@ Array.make (25 * 25551) 42.0 in
        ignore _arr;
        Unix.sleepf 0.1;
        if j=4 && !i mod 13 = 0 then failwith "oh no"; (* simulate a failure *)

        T.Trace.add_event scope @@ T.Event.make "done with alloc";
      with Failure _ ->
        ());
    done;
  done

let () =
  T.Globals.service_name := "t1";
  T.Globals.service_namespace := Some "ocaml-otel.test";
  Opentelemetry_client_ocurl.with_setup run