Feature/add usergroupid for product tax calculation

[ResuBaka]

I have updated the calculateProductTax to get the new feature to work.
This does only work when you set the tax.userGroupId to a number and have sourcePriceIncludesTax and calculateServerSide set to false.

Short description and why it's useful

This is adds tax calculation with product_tax_class_ids and customer_tax_class_ids.
We had the problem that when only the product_tax_class_ids we get the wrong taxes on a product to so we need to use both product_tax_class_ids and customer_tax_class_ids to get the right tax class for a product.

Which environment this relates to

Check your case. In case of any doubts please read about Release Cycle

• Test version (https://test.storefrontcloud.io) - this is a new feature or improvement for Vue Storefront. I've created branch from develop branch and want to merge it back to develop
• RC version (https://next.storefrontcloud.io) - this is a stabilisation fix for Release Candidate of Vue Storefront. I've created branch from release branch and want to merge it back to release
• Stable version (https://demo.storefrontcloud.io) - this is an important fix for current stable version. I've created branch from hotfix or master branch and want to merge it back to hotfix

Upgrade Notes and Changelog

• No upgrade steps required (100% backward compatibility and no breaking changes)
• I've updated the Upgrade notes and Changelog on how to port existing VS sites with this new feature

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Contribution and currently important rules acceptance

• I read and followed contribution rules
• I read the TypeScript Action Plan and adjusted my PR according to it
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[pkarw]

Cool; but two more things:

• we should take the user group from currently logged-in user - how to get it? https://github.com/DivanteLtd/vue-storefront/blob/c17c4ef7f59117692dea5d1649c8f399f6d9c3ce/core/lib/search.ts#L52
• we should apply this logic to vue-storefront-api to the taxcalc.js helper. The groupId in the API needs to be taken out from the request parameter - reference https://github.com/DivanteLtd/vue-storefront-api/blob/d1532f7eeac229da9e00733d0c9bc7f307fdbc12/src/api/catalog.js#L78

[pkarw]

Please do apply this logic to vue-storefront-api as well + add the support for dynamic groupId

[ResuBaka]

Did something change in vue-storefront because when I use my local Installation 1.9.0-rc2 then $vm0.$store.state.user.current.group_id is set but $vm0.$store.state.user.groupId is null.
Is that maybe something which is not set because we use magento1? @pkarw

For the api I would make an Issue for or i need to see how much time I have to work on it.

Then what do you mean by dynamic groupId?

[pkarw]

To be poerfectly honest with you - I'm not sure how this is being set :) @mdanilowicz was in charge of tier prices few months ago and add this dynamic groups mechanism by this change. But youre' right the group_id property should be on user as well so we could use it - but please just make sure it's the same with m2 and m1 as well

[ResuBaka]

I just found out to things first $vm0.$store.state.user.groupId is only set with the user.current.group_id when usePriceTiers is set to true and magento1 and magento2 has both user.current.group_id set.

The second one is that we need to redo all our tax calculation when a user login and his groupId is different from the one that is in the config.

[ResuBaka]

I need to change the code of PriceTiers a bit as I need to use the user groupId/groupToken as well and not only PriceTiers alone.

So we need to test that too after I am finished with the implementation.

[ResuBaka]

The PR for adding this also to the API can be found here.

[patzick]

Thanks @ResuBaka !