private ShopInformation()
 {
     Customers = new List<Customer>();
     Customers.Add(new Customer("test", "test"));
     Administrators = new List<Admin>();
     Administrators.Add(new Admin("Root", "qwerty"));
     AvailableProducts = new ProductsList();
     SoldProducts = new ProductsList();
     CurrentPromotion = new Promotion();
 }
 public void MakePromotion(string file)
 {
     if (this.IsLogged)
     {
         Promotion promotion = new Promotion();
         StreamReader reader = new StreamReader(file, Encoding.GetEncoding("UTF-8"));
         using (reader)
         {
             string line = reader.ReadLine();
             while (line != null)
             {
                 int productID = int.Parse(line);
                 string productName = reader.ReadLine();
                 decimal productPrice = decimal.Parse(reader.ReadLine());
                 promotion.PromotionList.Add(new Product(productName, productPrice, productID));
                 line = reader.ReadLine();
             }
         }
         ShopInformation.CurrentPromotion.PromotionList.Clear();
         ShopInformation.CurrentPromotion.PromotionList = promotion.PromotionList;
     }
     else
     {
         Console.WriteLine("This operation is not permitted. You should log on.");
     }
 }