Quantity Discount with Mix and match groups based on Square Footage

[ragomon]

I am currently going through the existing mods but as this is such a niche I have to look scrutinize anything that is even close. So I figured I would ask here in parallel.

Okay so essentially its combining the 3 key items in the title: Quantity Discount + Groups (mix and match) + SQF.

Lets use carpet for example.  The store sells 10 variations of carpets (A-J).  What we would be looking to do is setup a discount as follows

Discount

• 1 to 49 sqf = $20.00 per square foot
• 50-100 sqf = $19.00
• 100-150 sqf = $18.00

Mixable Groups - Now with the discounts based on total square footage above in mind we now need to be able to assign the discount rule to 1 or multiple products. More importantly any of these carpets in the cart will total together their SQF while exluding other other carpets. 

Example: We would want the discount rule above to apply only to Group 1 which we assigned Carpet type A, B, E, J.

As a customer, I order the following

• 25sqf xCarpet A
• 50sqf xCarpet C
• 25sqf xCarpet D
• 75sqf xCarpet J

So the logics would be 

100sqf @ $18.00 (Carpet A + J)

50spf @ $19.00 (Carpet C)

25sqf @ $20.00 (Carpet D)

= Total.

If anyone has seen a module plugin like this please let me know it would be very much appreciated.