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Sounds very simple....

You definitly not set that up using default behavior. You would need an extenstion and then store information on the order on the user choice of the possible products. And then add some. Alternatively you can consider creating a BOM "Free gift" where the option is to choose ProdA or ProdB as part of the config - probably not easy and also requires some coding against the orderlines.

A third option is to create 2 discounts - one for proda and one for prodb - and then let each of them trigger on a hidden voucher field (or custom field) where you stamp the user selection into that hidden field?

Thanks for your reply Nicolai. I agree it's not an easy task.

Can you elaborate on "You would need an extenstion and then store information on the order on the user choice of the possible products. And then add some."? Are you talking about a DiscountExtender or a fully custom (old) discount provider? And what do I need to add?

The other two options don't seem attractive at the moment as I could have a large number of products that are eligible as well as a large number of products that can be a gift. I simplified to ProdA and ProdB to explain the setup.

Thanks!

Imar

A custom DiscountExtender - not the old salesdiscountproviders.

Sorry to keep coming back to this but I am not sure how to implement this completely. 

With a DiscountExtender I get access to DiscountValidForProduct and DiscountValidForOrder which I can use to determine if the user is a first time subscriber. That's working currently (I use DiscountValidForProduct for that at the moment).

But then what? Should I use DiscountValidForProduct and then change the discount that is available on the extender? Or always return false from this method but manually add a discount line to the user's cart using Context.Cart when my code determines we should discount one of the products?

Thanks!

Imar

With the help from some black magic voodoo witch doctors, I think I have it working. Here's what I did in case someone else wants to try this:

1. Inherited from DiscountExtenderBase

2. Implemented the IDiscountExtenderCalculateOrderDiscount interface

3. When adding the gift to the cart, I add an OrderLineField to it called IsGift and set it to true. That way, I can have a normal product at any quantity and the same product as a gift in the cart side by side.

4. In DiscountValidForProduct, I check if the cart contains the gift product (by checking the OrderLineField and return true when it does. One tricky point here is that DiscountValidForProduct can be called multiple times for the same product: the one added as a regular product and the other as a gift. I return true on the first call only (using HttpContext items) and false on the other calls. This applies this discount just once.

5. One side effect of calling it multiple times is that the discount can be associated with the wrong order line (the regular product, not the gift as the order isn't guaranteed). So I also added a subscriber for Discounts.AfterDiscountCalculation where I check if the discount line points to the gift line correctly, and update it when it doesn't.

6. Finally, in GetDiscount of IDiscountExtenderCalculateOrderDiscount I return 0 when the cart doesn't contain a gift or I return a discount value which I derive from the gifted product at a quantity of 1.

On top of that I made a few changes to templates to highlight gifts and make sure you can't add more than one gift but these changes didn't have much to do with the discount calculation, more with the overall user flow.

If anyone ever needs functionality like this let me know and I can supply code and a walkthrough. You may have to give up your firstborn to make it work :-)

Thanks for the guidance Nicolai!

Imar

Well done Imar.

I am also assuming you changed the templates to determine when to show the options for Gifts. I assume that's #6, that by returning a dummy discount value, you render the gift card options/products (previously described in bullet #3 of how to add them). Is that accurate?

Best Regards,

Nuno Aguiar

>> I assume that's #6, that by returning a dummy discount value, you render the gift card options/products (previously described in bullet #3 of how to add them).

I have no idea what you are saying so it's probably not accurate :-)

I have a three step process:

1. Show normal products

2. Select a gift

3. Continue checkout

When you are allowed to add a gift, step 1 takes you to step 2. Otherwise, you are taken to step 3.

On step 2 we render a list of products from a specific group using a customized template that sets the IsGift order line field to true for the product you are adding. It also ensures you can add only one product by using radio buttons to select the gift. 

That's pretty much all.

Imar

Ah I see, you select the gifts when adding to Cart. I thought you were trying to do so within the cart, after considering the entire cart content, in case you were only entitled to a Gift if both Prod A and Prod B were in the cart (which would be harder to solve for).

Thanks for explaining that.