OpenTween.Twitter.userStream_StatusArrived C# (CSharp) Method

        private void userStream_StatusArrived(string line)
        {
            this._lastUserstreamDataReceived = DateTime.Now;
            if (string.IsNullOrEmpty(line)) return;

            if (line.First() != '{' || line.Last() != '}')
            {
                MyCommon.TraceOut("Invalid JSON (StatusArrived):" + Environment.NewLine + line);
                return;
            }

            var isDm = false;

            try
            {
                using (var jsonReader = JsonReaderWriterFactory.CreateJsonReader(Encoding.UTF8.GetBytes(line), XmlDictionaryReaderQuotas.Max))
                {
                    var xElm = XElement.Load(jsonReader);
                    if (xElm.Element("friends") != null)
                    {
                        Debug.WriteLine("friends");
                        return;
                    }
                    else if (xElm.Element("delete") != null)
                    {
                        Debug.WriteLine("delete");
                        Int64 id;
                        XElement idElm;
                        if ((idElm = xElm.Element("delete").Element("direct_message")?.Element("id")) != null)
                        {
                            id = 0;
                            long.TryParse(idElm.Value, out id);

                            this.PostDeleted?.Invoke(this, new PostDeletedEventArgs(id));
                        }
                        else if ((idElm = xElm.Element("delete").Element("status")?.Element("id")) != null)
                        {
                            id = 0;
                            long.TryParse(idElm.Value, out id);

                            this.PostDeleted?.Invoke(this, new PostDeletedEventArgs(id));
                        }
                        else
                        {
                            MyCommon.TraceOut("delete:" + line);
                            return;
                        }
                        for (int i = this.StoredEvent.Count - 1; i >= 0; i--)
                        {
                            var sEvt = this.StoredEvent[i];
                            if (sEvt.Id == id && (sEvt.Event == "favorite" || sEvt.Event == "unfavorite"))
                            {
                                this.StoredEvent.RemoveAt(i);
                            }
                        }
                        return;
                    }
                    else if (xElm.Element("limit") != null)
                    {
                        Debug.WriteLine(line);
                        return;
                    }
                    else if (xElm.Element("event") != null)
                    {
                        Debug.WriteLine("event: " + xElm.Element("event").Value);
                        CreateEventFromJson(line);
                        return;
                    }
                    else if (xElm.Element("direct_message") != null)
                    {
                        Debug.WriteLine("direct_message");
                        isDm = true;
                    }
                    else if (xElm.Element("retweeted_status") != null)
                    {
                        var sourceUserId = xElm.XPathSelectElement("/user/id_str").Value;
                        var targetUserId = xElm.XPathSelectElement("/retweeted_status/user/id_str").Value;

                        // 自分に関係しないリツイートの場合は無視する
                        var selfUserId = this.UserId.ToString();
                        if (sourceUserId == selfUserId || targetUserId == selfUserId)
                        {
                            // 公式 RT をイベントとしても扱う
                            var evt = CreateEventFromRetweet(xElm);
                            if (evt != null)
                            {
                                this.StoredEvent.Insert(0, evt);

                                this.UserStreamEventReceived?.Invoke(this, new UserStreamEventReceivedEventArgs(evt));
                            }
                        }

                        // 従来通り公式 RT の表示も行うため return しない
                    }
                    else if (xElm.Element("scrub_geo") != null)
                    {
                        try
                        {
                            TabInformations.GetInstance().ScrubGeoReserve(long.Parse(xElm.Element("scrub_geo").Element("user_id").Value),
                                                                        long.Parse(xElm.Element("scrub_geo").Element("up_to_status_id").Value));
                        }
                        catch(Exception)
                        {
                            MyCommon.TraceOut("scrub_geo:" + line);
                        }
                        return;
                    }
                }

                if (isDm)
                {
                    try
                    {
                        var message = TwitterStreamEventDirectMessage.ParseJson(line).DirectMessage;
                        this.CreateDirectMessagesFromJson(new[] { message }, MyCommon.WORKERTYPE.UserStream, false);
                    }
                    catch (SerializationException ex)
                    {
                        throw TwitterApiException.CreateFromException(ex, line);
                    }
                }
                else
                {
                    try
                    {
                        var status = TwitterStatusCompat.ParseJson(line);
                        this.CreatePostsFromJson(new[] { status.Normalize() }, MyCommon.WORKERTYPE.UserStream, null, false);
                    }
                    catch (SerializationException ex)
                    {
                        throw TwitterApiException.CreateFromException(ex, line);
                    }
                }
            }
            catch (WebApiException ex)
            {
                MyCommon.TraceOut(ex);
                return;
            }
            catch(NullReferenceException)
            {
                MyCommon.TraceOut("NullRef StatusArrived: " + line);
            }

            this.NewPostFromStream?.Invoke(this, EventArgs.Empty);
        }