public bool CanSale(string passport, string valueForSale, string currencyForSale)
        {
            RestrictionsRep restrictions = new RestrictionsRep();
            ClientRep       clientRep    = new ClientRep();
            Client          client       = new Client();

            double currencyRestriction = restrictions.GetCurrencyRestriction(currencyForSale);

            client = clientRep.SearchClientInFile(passport);
            double saleCurrency = Convert.ToDouble(client.SoldCurrency[currencyForSale]);
            double value        = Convert.ToDouble(valueForSale);

            double valueAfterSale = value + saleCurrency;

            double availableValue = currencyRestriction - valueAfterSale;

            if (availableValue > 0)
            {
                return(true);
            }
            else
            {
                return(false);
            }
        }
        public bool CanBuy(string passport, string valueForBuy, string currencyForBuy)
        {
            RestrictionsRep restrictions = new RestrictionsRep();
            ClientRep       clientRep    = new ClientRep();
            Client          client       = new Client();

            double currencyRestriction = restrictions.GetCurrencyRestriction(currencyForBuy);

            client = clientRep.SearchClientInFile(passport);
            double purchCurrency = Convert.ToDouble(client.PurchasedCurrency[currencyForBuy]);
            double value         = Convert.ToDouble(valueForBuy);

            double valueAfterPurch = value + purchCurrency;

            double availableValue = currencyRestriction - valueAfterPurch;

            if (availableValue > 0)
            {
                return(true);
            }
            else
            {
                return(false);
            }
        }