Use of gift certificate and coupon together - 1 needs to be disabled.

[PetleyJ]

Hi Guys.
Done a quick search to find nothing.

I want to be able to stop customers from using both gift certificates and coupons together.

Any way to do this?

[Ajeh]

Gift Certificates are Cash that the customer has paid you, been paid by someone else or something you have given the customer the same as Cash ...

Discount Coupons are a discount on Products ...

Why would you want to prevent someone from spending Cash and using a Discount Coupon at the same time?

Perhaps understanding a bit more of what is behind your question would help in working out a solution ...

[PetleyJ]

Hi Ajeh,

I understand what you mean. However we offer gift certificates as prizes for competitions.

So if we offer a gift certificate, and have a coupon a £20 item becomes £10.

I hope you get what I mean. Is there a way to disable one if a coupon is present.. or vice-versa.

[Ajeh]

This may work, but you will really need to test it and consider the implications of blocking Discount Coupons and GVs from being used at the same time ...

Edit the file:
/includes/modules/order_total/ot_coupon.php

and add the code in RED:

  function calculate_deductions($order_total) {
    global $db, $order, $messageStack, $currencies;
    $currencyDecimalPlaces = $currencies->get_decimal_places($_SESSION['currency']);
    $od_amount = array('tax'=>0, 'total'=>0);

    // bof: prevent Discount Coupon and GV from being used at the same time
    if ($_SESSION['cot_gv'] > 0.00 && (int)$_SESSION['cc_id'] > 0) {
      $_SESSION['cc_id'] = 0;
      define('TEXT_INVALID_COUPON_AND_GV', 'No Discount Coupon and GV, please use one or the other');
      $messageStack->add_session('redemptions', TEXT_INVALID_COUPON_AND_GV,'caution');
      $this->clear_posts();
      zen_redirect(zen_href_link(FILENAME_CHECKOUT_PAYMENT, '', 'SSL', true, false));
    }
    // eof: prevent Discount Coupon and GV from being used at the same time

    if ($_SESSION['cc_id'])

You need to test this for all combinations of redeeming GV and Discount Coupons to ensure reguardless of pattern that the GV can be claimed to add the amount to the customer balance, but that the GV and Discount Coupon cannot be used together ...

Example:
1 Add Discount Coupon only, go back to shopping, add GV amount

2 Add GV amount only, go back to shopping, add Discount Coupon

3 Add Discount Coupon and GV amount to claim, try to continue

4 Add Discount Coupon and GV redeem code and GV amount to claim, try to continue

5 Add Discount Coupon and GV redeem code, try to continue ... if taken to checkout_confirmation go back to checkout_payment and try to add GV amount to claim, try to continue

etc. etc. etc.

Results:
Always should be able to redeem GV but never be able to have both Discount Coupon and GV amount to claim at the same time when you get to checkout_confirmation

Issue to consider, I would, as a customer, be ticked off that I have a GV code (or balance) and a Discount Coupon and when I try to use them together I cannot so I would think about packing up my credit card and going home ...