public override async Task ExecuteAsync(Update update, Dictionary<string, string> parsedMessage)
        {
            var responseStream = new StreamReader(await GetCurrencyRates());
            var xmlDeserializer = new XmlSerializer(typeof(CurrencyContainerXml.DailyExRates));
            var currencyContainer = new CurrencyContainerXml() { DailyRates = xmlDeserializer.Deserialize(responseStream) as CurrencyContainerXml.DailyExRates };

            // Get data for previous date for comparison
            if (_previousDayCurrencyContainer == null ||
                DateTime.ParseExact(_previousDayCurrencyContainer.DailyRates.Date, "MM/dd/yyyy", null).AddDays(1) !=
                DateTime.ParseExact(currencyContainer.DailyRates.Date, "MM/dd/yyyy", null))
            {
                var ondate = DateTime.ParseExact(currencyContainer.DailyRates.Date, "MM/dd/yyyy", null).AddDays(-1);
                // Rates do not update on weekend (at least here, duh)
                if (ondate.DayOfWeek == DayOfWeek.Sunday)
                {
                    ondate = ondate.AddDays(-2);
                }
                var ondatestring = ondate.ToString(@"MM\/dd\/yyyy");
                responseStream = new StreamReader(await GetCurrencyRates(OnDateParam + ondatestring));
                _previousDayCurrencyContainer = new CurrencyContainerXml() { DailyRates = xmlDeserializer.Deserialize(responseStream) as CurrencyContainerXml.DailyExRates };
            }

            var sb = new StringBuilder();
            sb.Append("Курсы валют на ");
            sb.AppendLine(DateTime.ParseExact(currencyContainer.DailyRates.Date, "MM/dd/yyyy", null).ToShortDateString());
            sb.Append("По отношению к ");
            sb.AppendLine(DateTime.ParseExact(_previousDayCurrencyContainer.DailyRates.Date, "MM/dd/yyyy", null).ToShortDateString());
            sb.AppendLine();

            List<string> currenciesList = new List<string>();
            if (parsedMessage.ContainsKey("message"))
            {
                var names = parsedMessage["message"].Split(',').ToList();
                currenciesList.AddRange(names.Select(cname => cname.ToUpper()));
            }
            if (currenciesList.Count == 0)
                currenciesList = _defaultCurrenciesList;

            foreach (var currency in currencyContainer.DailyRates.Currency.Where(x => currenciesList.Contains(x.CharCode)))
            {
                sb.Append(currency.CharCode + ": " + currency.Rate);
                if (_previousDayCurrencyContainer != null)
                {
                    var diff = currency.Rate -
                               _previousDayCurrencyContainer.DailyRates.Currency.First(
                                   x => x.CharCode == currency.CharCode).Rate;
                    sb.Append(" _(");
                    sb.Append(diff > 0 ? "+" : "-");
                    sb.Append(Math.Abs(diff));
                    sb.Append(")_");
                }
                sb.AppendLine();
            }

            await Bot.SendTextMessage(update.Message.Chat.Id, sb.ToString(), false, update.Message.MessageId, null, true);
        }
        public override async Task ExecuteAsync(Update update, Dictionary <string, string> parsedMessage)
        {
            var responseStream    = new StreamReader(await GetCurrencyRates());
            var xmlDeserializer   = new XmlSerializer(typeof(CurrencyContainerXml.DailyExRates));
            var currencyContainer = new CurrencyContainerXml()
            {
                DailyRates = xmlDeserializer.Deserialize(responseStream) as CurrencyContainerXml.DailyExRates
            };

            // Get data for previous date for comparison
            if (_previousDayCurrencyContainer == null ||
                DateTime.ParseExact(_previousDayCurrencyContainer.DailyRates.Date, "MM/dd/yyyy", null).AddDays(1) !=
                DateTime.ParseExact(currencyContainer.DailyRates.Date, "MM/dd/yyyy", null))
            {
                var ondate = DateTime.ParseExact(currencyContainer.DailyRates.Date, "MM/dd/yyyy", null).AddDays(-1);
                // Rates do not update on weekend (at least here, duh)
                if (ondate.DayOfWeek == DayOfWeek.Sunday)
                {
                    ondate = ondate.AddDays(-2);
                }
                var ondatestring = ondate.ToString(@"MM\/dd\/yyyy");
                responseStream = new StreamReader(await GetCurrencyRates(OnDateParam + ondatestring));
                _previousDayCurrencyContainer = new CurrencyContainerXml()
                {
                    DailyRates = xmlDeserializer.Deserialize(responseStream) as CurrencyContainerXml.DailyExRates
                };
            }

            var sb = new StringBuilder();

            sb.Append("Курсы валют на ");
            sb.AppendLine(DateTime.ParseExact(currencyContainer.DailyRates.Date, "MM/dd/yyyy", null).ToShortDateString());
            sb.Append("По отношению к ");
            sb.AppendLine(DateTime.ParseExact(_previousDayCurrencyContainer.DailyRates.Date, "MM/dd/yyyy", null).ToShortDateString());
            sb.AppendLine();

            List <string> currenciesList = new List <string>();

            if (parsedMessage.ContainsKey("message"))
            {
                var names = parsedMessage["message"].Split(',').ToList();
                currenciesList.AddRange(names.Select(cname => cname.ToUpper()));
            }
            if (currenciesList.Count == 0)
            {
                currenciesList = _defaultCurrenciesList;
            }

            foreach (var currency in currencyContainer.DailyRates.Currency.Where(x => currenciesList.Contains(x.CharCode)))
            {
                sb.Append(currency.CharCode + ": " + currency.Rate);
                if (_previousDayCurrencyContainer != null)
                {
                    var diff = currency.Rate -
                               _previousDayCurrencyContainer.DailyRates.Currency.First(
                        x => x.CharCode == currency.CharCode).Rate;
                    sb.Append(" _(");
                    sb.Append(diff > 0 ? "+" : "-");
                    sb.Append(Math.Abs(diff));
                    sb.Append(")_");
                }
                sb.AppendLine();
            }

            await Bot.SendTextMessage(update.Message.Chat.Id, sb.ToString(), false, update.Message.MessageId, null, true);
        }