private double GetPrice(SkuCart cart)
        {
            // Getting popilated prices for each product (master data)
            IDictionary <char, double> priceOfEachItem = cart.GetAvailableProductsWithPrice();

            double totalPrice  = 0;
            bool   IsComboRule = checkForComboRule();

            foreach (var Product in _purchasedProductCount)
            {
                //Getting Rule defined for each product (sku id's)
                Tuple <int, double> Rule = PromotionRules.GetRule(Product.Key);
                if (Rule != null)
                {
                    //applying rule and calculating total price
                    totalPrice += (Product.Value / Rule.Item1) * Rule.Item2 + (Product.Value % Rule.Item1) * priceOfEachItem[Product.Key];
                }
                else
                //if there is no rule and it is not combo product(sku id) then calculating it's price
                if (!IsComboRule)
                {
                    totalPrice += priceOfEachItem[Product.Key] * Product.Value;
                }
            }

            if (!IsComboRule)
            {
                return(totalPrice);
            }
            else
            {
                return(caluculateComboRule(totalPrice, priceOfEachItem));
            }
        }