Coupon Discount Calculation Error?

[chris.tikkos@.....com]

Hello,

I noticed that even though i have selected Virtuemart to substract the discount BEFORE shipping and tax (i can confirm this in the basket), OPC calculates the discount always AFTER shipping and tax! So there is an inconsistency. Is this a bug or am i missing some configuration option?

You may confirm this at http://www.quality-tuning.com (you may use test coupon code 2TEST4 also select a European Union country for VAT)

Regards,
Chris

[admin]

Hello chris,
for the problems with javascript and validation of user input, i recommend to update to latest version 261. For the coupon issues: are you using awo coupons or vm coupons?

Regards,
Stan Scholtz

[chris.tikkos@.....com]

Hi Stan,

We are using vm coupons.

Rgrds,
Chris

[chris.tikkos@.....com]

We checked also with Awo Coupons and we have the same error

[chris.tikkos@.....com]

We noticed that problem exists only with Percentage coupons, not with Total Coupons.

Rgrds,
Chris

[chris.tikkos@.....com]

Hi Stan,

Any news regarding this bug? It still remains in the latest version of OPC; the calculation of Percentage type coupons is wrong unfortunately.

Thanks in advance,
Chris

[admin]

Hello Chris,
i started to investigate this bug, the main coupon function is called from /components/com_onepage/ajax/ajaxhelper.php depending on whether you use awo or not. The total is sent with $_POST variable, but i am afraid, that having turned on "payment discout before tax" option does not concern ordinary discounts, because it decides whether to count the percentual coupons from price with or without price accourding to setting in the shopper group which in your case is most probably "show prices including taxes". Therefore this is not considered a bug at the moment, but rather a new feature where i could modify the total for your special case.

Awo counts taxes and totals from their own function and it also decides percentual coupons according to shopper group settings instead of "payment discount before tax" VM glogal setting.

I can work on this feature, but will take another couple of days.

Best Regards,
Stan

[chris.tikkos@.....com]

Stan,

Thanks for starting investigation for this issue. To make things easier we have completely uninstalled AWO coupons and using virtuemart's coupons only. The problem is the same: if we disable OPC, percentage coupons are calculated correctly, however when we enable OPC the discounts are calculated wrongly! So we still think that there is some issue with OPC, you can verify this anytime in our website if you like.

For your info, we need the discount to be calculated prior to shipping and taxes (we have checked this in VM config) and in our website the prices are shown WITHOUT tax.

Thanks in advance for your help!

Chris

[admin]

Ok, now 1.2.276 version and above counts percentual coupons from product subtotal when "payment discount before tax and shipping" is turned on in VM config.

[chris.tikkos@.....com]

This is great news, we confirm that it's now working properly, thanks!!