Apply WooCommerce Coupon code to checkout - php

Question

I am trying to create a "Product Redeem Page as shown in this tutorial on SitePoint.
Problem is that the product does indeed gets added to the cart and you can proceed to the checkout, but the discount that is associated with the coupon code is not automagically applied. In the coupon code I created the value is set to 100% discount.
You could apply te coupon code again via the "Do you have a coupon code" fly out on the checkout page, but this defeats the whole purpose.
I also did not get this code working to begin with, but I was able to figure out that:
// Check coupon to make determine if its valid or not
if( ! $coupon->id && ! isset( $coupon->id ) ) {
...Rest of code here...
should be:
// Check coupon to make determine if its valid or not
if( ! $coupon->id && ! isset( $coupon_id ) ) {
Please note the second Not isset variable name. Maybe this does work, but is not the proper way of handling things, everybody knows, but me.
Sadly I am out of my comfort zone a.t.m., but I am willing to learn by making mistakes and figuring out how to fix them and learn from people who are way smarter then me and/or way more advanced. In my direct cirlce of friends I have no one that I could aks and get any other answer then: "Huh?!?", so I am giving it a shot here on Stackoverflow.
A link to the tutorial on SitePoint only is probably not appreciated, so here is the complete code I am using:
The Ajax handlers added in functions.php
add_action( 'wp_ajax_spyr_coupon_redeem_handler', 'spyr_coupon_redeem_handler' );
add_action( 'wp_ajax_nopriv_spyr_coupon_redeem_handler', 'spyr_coupon_redeem_handler' );
The coupon login also added to functions.php
function spyr_coupon_redeem_handler() {
// Get the value of the coupon code
$code = $_REQUEST['coupon_code'];
// Check coupon code to make sure is not empty
if( empty( $code ) || !isset( $code ) ) {
// Build our response
$response = array(
'result' => 'error',
'message' => 'Code text field can not be empty.'
);
header( 'Content-Type: application/json' );
echo json_encode( $response );
// Always exit when doing ajax
exit();
}
// Create an instance of WC_Coupon with our code
$coupon = new WC_Coupon( $code );
// Check coupon to make determine if its valid or not
if( ! $coupon->id && ! isset( $coupon_id ) ) {
// Build our response
$response = array(
'result' => 'error',
'message' => 'Invalid code entered. Please try again.'
);
header( 'Content-Type: application/json' );
echo json_encode( $response );
// Always exit when doing ajax
exit();
} else {
// Attempting to add the coupon code as a discount.
WC()->cart->add_discount( $code );
// Coupon must be valid so we must
// populate the cart with the attached products
foreach( $coupon->product_ids as $prod_id ) {
WC()->cart->add_to_cart( $prod_id );
}
// Build our response
$response = array(
'result' => 'success',
'href' => WC()->cart->get_cart_url()
);
header( 'Content-Type: application/json' );
echo json_encode( $response );
// Always exit when doing ajax
exit();
}
}
The jQuery form submission code, enqueued via the registered Ajax handlers in functions.php
jQuery( document ).ready( function() {
jQuery( '#ajax-coupon-redeem input[type="submit"]').click( function( ev ) {
// Get the coupon code
var code = jQuery( 'input#coupon').val();
// We are going to send this for processing
data = {
action: 'spyr_coupon_redeem_handler',
coupon_code: code
}
// Send it over to WordPress.
jQuery.post( woocommerce_params.ajax_url, data, function( returned_data ) {
if( returned_data.result == 'error' ) {
jQuery( 'p.result' ).html( returned_data.message );
} else {
// Hijack the browser and redirect user to cart page
window.location.href = returned_data.href;
}
})
// Prevent the form from submitting
ev.preventDefault();
});
});
Thanks in advance of pointing me in the right direction.

Answer 1

Update: At this moment I got the wanted functionality working.
What needed to be done is to add:
// Let's add the discount to the cart.
global $woocommerce;
WC()->cart->add_discount( $code );
inside the foreach statement. The complete else statement now looks like this:
} else {
// Coupon must be valid so we must
// populate the cart with the attached products
foreach( $coupon->product_ids as $prod_id ) {
WC()->cart->add_to_cart( $prod_id );
// Let's add the discount to the cart.
global $woocommerce;
WC()->cart->add_discount( $code );
}
// Build our response
$response = array(
'result' => 'success',
'href' => WC()->cart->get_cart_url()
);
header( 'Content-Type: application/json' );
echo json_encode( $response );
// Always exit when doing ajax
exit();
I'm still not sure if this is the correct way of handeling this, but it seems to work.
For instance I am calling(?!) the global $woocommerce variable, but below I am using the global(?!) class WC() to add the coupon. Not sure if this is as clean and logical as it gets.
If anybody knows of a better/cleaner way, please let me know! I am happy to learn from you guys and maybe one day I may be able to return the favour, who knows.