Free Shipping coupon for 1 item makes all shipping free

[Chris Stackhouse]

Anyone ever figure this one out? I'm stuck in this same situation where my client needs to offer a free shipping coupon but only on certain items. It would even be acceptable if instead it would just refuse to validate the coupon and display a warning if the cart contains items that are not specifically allowed by the coupon. I suppose we would need to compare an array of the items in the cart to an array of allowed items in the coupon restrictions. In fact, the basic functionality for this proposed solution should already exist in normal coupon validation as a condition of proceeding beyond Step 2 of the checkout process. I will investigate.

[Chris Stackhouse]

The following solution seems to be working as I intended in my previous post.

Around line 200 of includes/modules/order_total/ot_coupon.php

        $products = $_SESSION['cart']->get_products();
        $foundvalid = true;

        if ($foundvalid == true) {
          $foundvalid = false;
          for ($i=0; $i<sizeof($products); $i++) {
            if (is_product_valid($products[$i]['id'], $coupon_result->fields['coupon_id'])) {
              $foundvalid = true;
              continue;
            }
          }
        }
//BOF Restrictive Free Shipping -- Invalidate Coupon if order contains ANY restricted items
     if ($coupon_result->fields['coupon_type'] == 'S') {
     $products = $_SESSION['cart']->get_products();
     $validproducts = 0;
    $totalproducts= sizeof($products);
          
          for ($i=0; $i<sizeof($products); $i++) {
            if (is_product_valid($products[$i]['id'], $coupon_result->fields['coupon_id'])) {
              $validproducts= $validproducts +1;
              continue;
            }
          }
        }
     

if ($totalproducts > $validproducts) {
          $messageStack->add_session('redemptions', TEXT_INVALID_RESTRICTIVE_FREE_SHIPPING,'caution');
          $this->clear_posts();
          zen_redirect(zen_href_link(FILENAME_CHECKOUT_PAYMENT, '', 'SSL',true, false));
}
//EOF Restrictive Free Shipping

        if (!$foundvalid) {
          $this->clear_posts();
        } 

add the following line somewhere in includes/languages/custom/english.php :

define('TEXT_INVALID_RESTRICTIVE_FREE_SHIPPING', 'Some items in your cart do not qualify for FREE SHIPPING.  Remove them and re-enter coupon code.' 

[Ajeh]

Thanks for the update on how you handled this ... I always assumed that was an obvious thing to do but it helps to know a simple solution like that (but simple is simple to us and not the average store owner) is posted on the Free Forums ...

[Chris Stackhouse]

No problem. I also intend to add an additional configuration value to TABLE_COUPONS and edit admin/coupon_admin.php to insert a checkbox so that Restrictive Free Shipping can be toggled on or off for each individual coupon code. I will post an update when its complete.

[Ajeh]

What specifically is the restriction that you want for the checkbox?

[bislewl]

I had the same issue today where it was desired to have a "Free Shipping" coupon apply only to certain products, and if excluded products where in there they would be charged the difference of the shipping cost. So I thought I would share.

Here is some general direction how to accomplish it, you will need some coding experience to make this work for your store this is just a general idea. This also really only works for stores that don't charge tax on shipping & are restricting the coupon on a per product level, NOT per category. So you would need to modify it further to do that. ALSO it doesn't account for % or additional discount besides to free shipping. But it is here to help provide so general direction.

Everything I did was in the includes/modules/order_total/ot_coupon.php

in the process() function comment out so the customer see the actual complete shipping cost:
if ($od_amount['type'] == 'S' || $od_amount['type'] == 'E' || $od_amount['type'] == 'O') $order->info['shipping_cost'] = 0;

towards then end of the calculate_deductions() function:
After the end of the switch ($this->calculate_tax) {
}

I added this:

$coupon_restrictions = $db->Execute("SELECT * FROM " . TABLE_COUPON_RESTRICT . " WHERE coupon_id='" . (int)$_SESSION['cc_id'] . "'");
                    if (in_array($coupon->fields['coupon_type'], array('S', 'E', 'O')) && $coupon_restrictions->RecordCount() > 0) {
                        $restricted_items = array();
                        $allowed_items = array();
                        $restricted_items_in = array();
                        $allowed_items_in = array();
                        while (!$coupon_restrictions->EOF) {
                            if ($coupon_restrictions->fields['coupon_restrict'] == 'Y') {
                                $restricted_items[] = $coupon_restrictions->fields['product_id'];
                                if ($_SESSION['cart']->get_products($coupon_restrictions->fields['product_id']) > 0) {
                                    $restricted_items_in[] = $coupon_restrictions->fields['product_id'];
                                }
                            } else {
                                $allowed_items[] = $coupon_restrictions->fields['product_id'];
                                if ($_SESSION['cart']->get_products($coupon_restrictions->fields['product_id']) > 0) {
                                    $allowed_items_in[] = array('product_id' => $coupon_restrictions->fields['product_id'],
                                        'quantity' => $_SESSION['cart']->get_quantity($coupon_restrictions->fields['product_id']),
                                        'weight' => zen_products_lookup($coupon_restrictions->fields['product_id'], 'products_weight')
                                    );
                                }
                            }
                            $coupon_restrictions->MoveNext();
                        }
                        if (count($allowed_items_in) > 0 && count($restricted_items_in) > 0) {
                            $od_amount['total'] = $this->_get_ups_cost_for_free_ship_items($allowed_items_in);
                        }
                    } 

In this case using UPS shipping module, so I created a function _get_ups_cost_for_free_ship_items() to basically make a call to UPS and determine the shipping cost for those that are allowed, and the re-adjusting the total discount amount with the shipping cost for those approved products