Redirect from Woo Product to associated Course (bi-directional field setup)

gistfile1.txt

// this function redirects users to the course they purchased
// when they try to access the WooCommerce product that sold the course
// as they don't need to see the sales page anymore, they want the lessons
add_action( 'template_redirect', 'c_redirect_to_purchased_course' );
function c_redirect_to_purchased_course() {

    // if it's not a woo product page, return and do nothing
    if( !is_product() ) return;
    // get related courses
    $c_products_related_courses = get_field('c_products_related_courses');
    // if no related courses set, return and continue to show the product page
    if( !$c_products_related_courses ) return;

    // there is only be one item in array as we limited the field in ACF set to 1 item max
    // so we can get the first item in array which gives us the ID of the related course
    $c_products_related_course_id = $c_products_related_courses[0];

    // get current wordpress user
    $current_user = wp_get_current_user();

    // if the current wordpress user has purchase the woo product we are trying to load
    // that sold the online course
    if ( wc_customer_bought_product( wp_get_current_user()->user_email, get_current_user_id(), get_the_ID() ) ) {
        // then lets redirect to the URL of the related course
        wp_redirect( get_permalink($c_products_related_course_id) );
        exit;
    }

}

// we use the true/false return of this function
// to show / hide elements on our course page for people who
// have purchased VS have not purchased
function c_check_user_access_this_course(){
    
    // if its not a single course, do nothing and stop function
    if ( ! is_singular('course') ) return false;

    // always show for admins to help with website management
    if(current_user_can('administrator')) return true;

    // get the current wp user
    $current_user = wp_get_current_user();

    // this will always be an array
    $c_course_related_woo_products = get_field('c_course_related_woo_products');
    // if there are related woo products assigned to this course
    if($c_course_related_woo_products){
        if ( wc_customer_bought_product( wp_get_current_user()->user_email, get_current_user_id(), $c_course_related_woo_products[0] ) ) {
            return true;
        }
    }
    return false;
}