Retain Cart when market is change

A cart is a collection of products that are selected by a website customer.

Working on multi-market site, comes with a problem when we switch from one market to another market it does create new cart for each market.

Note from optimizely :- Carts are market-dependent, so are unique to a user and market, instead of just a user. If a site lets a user switch markets, then switching the market may also switch associate carts to a new or different carts.

So, here is my solution for this instead of recreating the whole cart, we can just change the market fields and payment data in cart and market data in cookie(i.e for users).

Step-1 

Delete if any existing carts are present to your desitination market.

 var userId = _customerContext.CurrentContactId.ToString();
 var cartName = cart.Name;

var previousCart = _orderRepository.LoadCart<ICart>(new Guid(userId), cartName, selectedShippingAddressRegion);

if (previousCart != null)
    _orderRepository.Delete(previousCart.OrderLink);

Step-2

Change Market data in current cart

cart.MarketId = new MarketId(destinationMarket);
var marketName = _marketManager.GetAllActiveMarkets().Where(c => c.IsEnabled)
                .FirstOrDefault(x => x.MarketId.Value == destinationMarket)?.MarketName;

cart.MarketName = marketName;
this._orderRepository.Save(cart);

Step-3 

Update cookie with destinatin market

 var market = GetMarket(marketId);
 SiteContext.Current.Currency = market.DefaultCurrency;
 _cookieService.Set(MarketCookie, marketId.Value);
 MarketEvent.OnChangeMarket(market, new EventArgs());

Step-4 

if (cart != null)
{
     UpdateLineItemPrice(cart);
     _orderRepository.Save(cart);
}

 public void UpdateLineItemPrice(ICart cart)
 {
    if (cart == null)
        return;
     foreach (var lineItem in cart.GetAllLineItems())
      {
        lineItem.PlacedPrice = _priceCalculationManager.GetSalePrice(lineItem.Code, cart.MarketId, cart.Currency).UnitPrice.Amount;
       }
        ValidateCart(cart);
}

Result:- With these steps when we change the market it will carry our current cart to new market with updated market fields and price.

Notes :- 

• All service call made with dependency injection and all of them are present with optimizely liberary.
• Depending with impemention of cart , we might need to update shipping address as well it will be similar like what we did with price.
• Price should be present at the variant level in commerce manager with respect to market.