open Nock_lib

let rec find_project_root dir =
  let pills_dir = Filename.concat dir "pills" in
  if Sys.file_exists pills_dir && Sys.is_directory pills_dir then dir
  else
    let parent = Filename.dirname dir in
    if String.equal parent dir then failwith "unable to locate project root containing pills/"
    else find_project_root parent

let project_root =
  match Sys.getenv_opt "NEOVERE_ROOT" with
  | Some root -> root
  | None ->
      let exe_dir = Filename.dirname Sys.executable_name in
      find_project_root exe_dir

let () =
  Printf.printf "\n╔═══════════════════════════════════════════════════════╗\n";
  Printf.printf "║  Event Replay Test                                    ║\n";
  Printf.printf "╚═══════════════════════════════════════════════════════╝\n\n";

  let pier_path = Filename.concat project_root "test-pier" in

  (* Check if pier exists *)
  if not (Sys.file_exists pier_path) then begin
    Printf.printf "✗ Test pier not found at: %s\n" pier_path;
    Printf.printf "  Run test_pier_boot.exe first to create it\n";
    exit 1
  end;

  Printf.printf "Using test pier at: %s\n\n%!" pier_path;

  (* Step 1: Boot ivory kernel (fresh state, no persistence) *)
  Printf.printf "[1] Booting fresh ivory kernel...\n%!";
  let state = State.create () in
  let ivory_path = Filename.concat project_root "pills/ivory.pill" in
  begin match Boot.boot_ivory state ivory_path with
  | Error (Boot.Invalid_pill msg) ->
      Printf.printf "✗ Ivory boot failed: %s\n%!" msg;
      exit 1
  | Error (Boot.Unsupported msg) ->
      Printf.printf "✗ Unsupported: %s\n%!" msg;
      exit 1
  | Ok () ->
      Printf.printf "✓ Ivory kernel loaded\n\n%!";
  end;

  (* Step 2: Load eventlog and replay events *)
  Printf.printf "[2] Creating eventlog handle and replaying events...\n%!";
  let eventlog = Eventlog.create ~enabled:false pier_path in

  let event_count = ref 0 in
  let replay_callback num event =
    incr event_count;
    if !event_count mod 10 = 0 || !event_count <= 5 then
      Printf.printf "  Replaying event %Ld...\n%!" num;
    (* Poke the event into the state *)
    ignore (State.poke state event)
  in

  Eventlog.replay ~verbose:true eventlog replay_callback;

  let final_eve = State.event_number state in
  Printf.printf "✓ Replay complete!\n%!";
  Printf.printf "  Events replayed: %d\n%!" !event_count;
  Printf.printf "  Final event number: %Ld\n\n%!" final_eve;

  (* Step 3: Verify we can still poke events *)
  Printf.printf "[3] Testing state is functional after replay...\n%!";
  Printf.printf "  (State should be able to process new events)\n%!";

  Printf.printf "\n╔═══════════════════════════════════════════════════════╗\n";
  Printf.printf "║  Event Replay Test SUCCESS! 🎉                        ║\n";
  Printf.printf "╚═══════════════════════════════════════════════════════╝\n\n";

  Printf.printf "Replayed %d events from disk\n" !event_count;
  Printf.printf "State is at event number: %Ld\n\n" final_eve