Auto apply a coupon for a specific product based on Woocommerce cart subtotal

Question

Referring to this question: Apply a coupon programmatically in Woocommerce and then this one:How to apply an automatic discount in WooCommerce based on cart total?

Complete rookie here. I need to auto-apply an already existing coupon to one particular product when the subtotal of other products in the cart is $40. And I need to make sure that applying the discount doesn't create a loop by taking the coupon out due to dropping the total below the $40 threshold.

I'm not sure how to modify this code to do that:

add_action('woocommerce_before_checkout_process','add_discount_at_checkout');

function add_discount_at_checkout(){
global $woocommerce;
$minorder = 99;
if( $woocommerce->cart->get_cart()->cart_contents_total>$minorder){

 //APPLY COUPON HERE

}
}

I suggest you do add some of the code variations you have tried. And explain the subsequent results. Just adding some code you think you could use does not hold much water. Also, this question was perhaps better placed at wordpress.stackexchange.com . — rhand
I haven't tried any code yet as I am not a coder, the cart is an unstable one (long story) so trying things at random is dangerous, and I've not found code that does specifically what I am asking. — SilkRoadDog

LoicTheAztec LoicTheAztec · Accepted Answer · 2019-03-02T08:47:25

First the targeted coupon code need to be set as restricted to the targeted product only:

The following code will apply a specific coupon (a discount) just to a specific cart item if the cart subtotal (excluding this specific cart item) is up to $40:

add_action('woocommerce_before_calculate_totals', 'discount_based_on_total_threshold');
function discount_based_on_total_threshold( $cart ) {
    if ( is_admin() && ! defined( 'DOING_AJAX' ) )
        return;

    if ( did_action( 'woocommerce_before_calculate_totals' ) >= 2 )
        return;

    // Your settings
    $coupon_code      = 'summer'; // Coupon code
    $amount_threshold = 40; // Total amount threshold
    $targeted_product = 37; // Targeted product ID

    // Initializing variables
    $total_amount     = 0;
    $applied_coupons  = $cart->get_applied_coupons();
    $coupon_code      = sanitize_text_field( $coupon_code );
    $found            = false;

    // Loop through cart items
    foreach( $cart->get_cart() as $cart_item ) {
        if( ! in_array( $targeted_product, array( $cart_item['product_id'], $cart_item['data']->get_id() ) ) ) {
            // Get the cart total amount (excluding the targeted product)
            $total_amount += $cart_item['line_total'] + $cart_item['line_tax'];
        } else {
            // Targeted product is found
            $found = true;
        }
    }

    // Applying coupon
    if( ! in_array($coupon_code, $applied_coupons) && $found && $total_amount >= $amount_threshold ){
        $cart->add_discount( $coupon_code );
    }
    // Removing coupon
    elseif( in_array($coupon_code, $applied_coupons) && ( $total_amount < $amount_threshold || ! $found ) ){
        $cart->remove_coupon( $coupon_code );
    }
}

Code goes in function.php file of your active child theme (or active theme). Tested and works.

Auto apply a coupon for a specific product based on Woocommerce cart subtotal

1 Answers