dwds/web/reloader/legacy_restarter.dart

// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'dart:async';
import 'dart:html';
import 'dart:js';

import 'restarter.dart';

class LegacyRestarter implements Restarter {
  @override
  Future<bool> restart() async {
    var dartLibrary = context['dart_library'] as JsObject;
    dartLibrary.callMethod('reload');
    var reloadCompleter = Completer<bool>();
    StreamSubscription sub;
    sub = window.onMessage.listen((event) {
      var message = event.data;
      if (message is Map &&
          message['type'] == 'DDC_STATE_CHANGE' &&
          message['state'] == 'restart_end') {
        reloadCompleter.complete(true);
        sub.cancel();
      }
    });
    return reloadCompleter.future;
  }
}