mixed VAT in BOM sales

Hello, I need your help on an issue we have with a client.

They are selling gift packs with food and non food items in the pack. Packs are set as BOM in SAP.

In the packs, some items are taxed at a VAT rate of 5% (food) and others at 20%(wine).

We would need to calculate the VAT rate as the sum of the 5% VAT applied on food items and the 20% VAT applied on the wine.

However, the price of the pack is not the sum of the price of the materials in it, there is a reduction. For exemple, the pack at 30 euros contains a paté at 20 euros and a bottle of wine at 15 euros. The theoretical price of the pack is 35 euros but sold at 30 euros.

We would need to calculate the VAT at the prorata of the item prices in the pack.

for exemple, here, the price of paté in the pack is 20 * 30(price of pack)/35 (total price of items) and we would calculate the 5% VAT on this amount. Same thing for the 20% VAT rate.

On the invoice, we would need to have the net price, the 5% VAT and the 20% VAT, all at the BOM header level.

In france, we can not declare a custom VAT rate like 17.2%, it has to be 20% and 5%.

Do you have an idea on how to do this in SAP please ?

Thank you