public bool AddItem(Product product, double orderQuantity)
{
if (HasCouponApplied || HasCampaignsApplied)
{
return(false); //You cannot add a product in cart after applying campaign or coupon
}
if (product == null || orderQuantity <= 0)
{
return(false); //Invalid item to add
}
if (CartItems.ContainsKey(product.Title))
{
CartItems[product.Title] = CartItems[product.Title].AddQuantity(orderQuantity);
}
else
{
CartItems.Add(product.Title, new ShoppingCartItem(product, orderQuantity));
}
return(true);
}