Facebook.FacebookClient.ProcessResponse C# (CSharp) Method

        private object ProcessResponse(HttpHelper httpHelper, string responseString, Type resultType, bool containsEtag, IList<int> batchEtags)
        {
            try
            {
                object result = null;

                Exception exception = null;
                if (httpHelper == null)
                {
                    // batch row
                    result = DeserializeJson(responseString, resultType);
                }
                else
                {
                    var response = httpHelper.HttpWebResponse;

                    if (response == null)
                        throw new InvalidOperationException(UnknownResponse);

                    if (response.ContentType.Contains("text/javascript") ||
                        response.ContentType.Contains("application/json"))
                    {
                        result = DeserializeJson(responseString, null);
                        exception = GetException(httpHelper, result);
                        if (exception == null)
                        {
                            if (resultType != null)
                                result = DeserializeJson(responseString, resultType);
                        }
                    }
                    else if (response.StatusCode == HttpStatusCode.OK && response.ContentType.Contains("text/plain"))
                    {
                        if (response.ResponseUri.AbsolutePath.EndsWith("/oauth/access_token"))
                        {
                            var body = new JsonObject();
                            foreach (var kvp in responseString.Split('&'))
                            {
                                var split = kvp.Split('=');
                                if (split.Length == 2)
                                    body[split[0]] = split[1];
                            }

                            if (body.ContainsKey("expires"))
                                body["expires"] = Convert.ToInt64(body["expires"], CultureInfo.InvariantCulture);

                            result = DeserializeJson(body.ToString(), resultType);

                            return result;
                        }
                        else
                        {
                            throw new InvalidOperationException(UnknownResponse);
                        }
                    }
                    else
                    {
                        throw new InvalidOperationException(UnknownResponse);
                    }
                }

                if (exception == null)
                {
                    if (containsEtag && httpHelper != null)
                    {
                        var json = new JsonObject();
                        var response = httpHelper.HttpWebResponse;

                        var headers = new JsonObject();
                        foreach (var headerName in response.Headers.AllKeys)
                            headers[headerName] = response.Headers[headerName];

                        json["headers"] = headers;
                        json["body"] = result;

                        return json;
                    }

                    return batchEtags == null ? result : ProcessBatchResponse(result, batchEtags);
                }

                throw exception;
            }
            catch (FacebookApiException)
            {
                throw;
            }
            catch (Exception)
            {
                if (httpHelper != null && httpHelper.InnerException != null)
                    throw httpHelper.InnerException;

                throw;
            }
        }