LearnDash Nested Lesson URLs #2

/**
 * Fix lesson query if "Nested URLs" are enabled (add original course name to the query)
 */
function pm_query_lesson_url($query, $old_query = '') {
    global $wpdb, $wp, $pm_query;

    if(empty($wp->request)) {
        return $query;
    }

    $lesson_cpt_slug = pm_get_ldms_rewrite_slug('lesson');

    // A. Detect nested lesson URLs
    if(strpos($wp->request, "/{$lesson_cpt_slug}/") !== false) {
        preg_match("/([^\/]+)\/{$lesson_cpt_slug}\/([^\/]+)(?:.+?([^\/]+)$)?/", $wp->request, $parts);

        if(!empty($parts[2])) {
            $query = array(
                'do_not_redirect' => 1,
                'sfwd-courses' => $parts[1],
                'sfwd-lessons' => $parts[2],
                'name' => $parts[2],
                'post_type' => 'sfwd-lessons'
            );
        }

        if(!empty($parts[3])) {
            $topic_quiz = sanitize_title($parts[3]);
            $post_type = $wpdb->get_var($wpdb->prepare("SELECT post_type FROM {$wpdb->posts} WHERE post_name = %s", $topic_quiz));

            if(!empty($post_type) && in_array($post_type, array('sfwd-topic', 'sfwd-quiz'))) {
                $query[$post_type] = $topic_quiz;
                $query['post_type'] = $post_type;
            }
        }
    }
    // B. Check if requested slug is used by any lesson/topic/quiz
    else if(strpos($wp->request, "/") === false) {
        $lesson = $wpdb->get_row($wpdb->prepare("
            SELECT * FROM {$wpdb->posts}
            WHERE post_name = %s
            AND post_type IN ('sfwd-lessons', 'sfwd-topic', 'sfwd-quiz')
            ",
            basename($wp->request)
        ));

        if(!empty($lesson->post_type)) {
            $course_id = learndash_get_course_id($lesson->ID);
            $course_name = get_post_field('post_name', $course_id);

            $query = array(
                $lesson->post_type => $lesson->post_name,
                'name' => $lesson->post_name,
                'post_type' => $lesson->post_type
            );

            if(!empty($course_name)) {
                $query['sfwd-courses'] = $course_name;
                $query['do_not_redirect'] = 1;
            } else {
                $query['do_not_redirect'] = 1;
            }
        }
    }

    return $query;
}
add_filter('request', 'pm_query_lesson_url', 10, 2);

/**
 * Get rewrite slug for 'lesson'
 */
function pm_get_ldms_rewrite_slug($post_type = '') {
    if(function_exists('learndash_get_post_type_slug') && !empty($post_type)) {
        $lesson_cpt_slug = learndash_get_post_type_slug('lesson');
        $lesson_cpt_obj = get_post_type_object($lesson_cpt_slug);
        $lesson_cpt_slug = apply_filters('learndash_post_type_rewrite_slug', $lesson_cpt_obj->rewrite['slug'], $lesson_cpt_slug);
    } else {
        $lesson_cpt_slug = $post_type;
    }

    return $lesson_cpt_slug;
}

/**
 * Add course URL to lesson URL if "Nested URLs" are enabled
 */
function pm_append_course_name($permalink, $post) {
    if(empty($post->post_type)) {
        return $permalink;
    }

    // Get the dynamically generated course name
    if(in_array($post->post_type, array('sfwd-lessons', 'sfwd-topic', 'sfwd-quiz')) && function_exists('learndash_get_course_id')) {
        // Keep the old permalink in a separate variable
        $old_permalink = $permalink;
        $permalink_base = trim(get_option('home'), "/");

        $course_id = apply_filters('learndash_post_link_course_id', learndash_get_course_id($post->ID), $old_permalink, $post);

        if(!empty($course_id)) {
            $course_name = get_post_field('post_name', $course_id);
            $lesson_cpt_slug = pm_get_ldms_rewrite_slug('lesson');
        }

        // A. Change 'Lesson' permalink
        if($post->post_type == 'sfwd-lessons') {
            $sfwd_lessons = get_post_meta($post->ID, '_sfwd-lessons', true);

            if(!empty($course_name) && empty($sfwd_lessons['sfwd-lessons_sample_lesson'])) {
                $new_permalink = sprintf('%s/%s/%s/%s', $permalink_base, $course_name, $lesson_cpt_slug, $post->post_name);
            } else {
                $new_permalink = sprintf('%s/%s', $permalink_base, $post->post_name);
            }
        }

        // B. Change 'Topic' & 'Quiz' permalink
        if(in_array($post->post_type, array('sfwd-topic', 'sfwd-quiz')) && !empty($course_name) && class_exists('LearnDash_Settings_Section')) {
            if(LearnDash_Settings_Section::get_section_setting('LearnDash_Settings_Courses_Builder', 'shared_steps') == 'yes' && function_exists('learndash_course_get_single_parent_step')) {
                $lesson_id = learndash_course_get_single_parent_step($course_id, $post->ID);
            } else if(function_exists('learndash_get_lesson_id')) {
                $lesson_id = learndash_get_lesson_id($post->ID);
            }

            $sfwd_lessons = get_post_meta($lesson_id, '_sfwd-lessons', true);

            if(!empty($lesson_id)) {
                $lesson_name = get_post_field('post_name', $lesson_id);

                if(empty($sfwd_lessons['sfwd-lessons_sample_lesson'])) {
                    $new_permalink = sprintf('%s/%s/%s/%s/%s', $permalink_base, $course_name, $lesson_cpt_slug, $lesson_name, $post->post_name);
                } else {
                    $new_permalink = sprintf('%s/%s/%s', $permalink_base, $lesson_name, $post->post_name);
                }
            }
        }
    }

    return (!empty($new_permalink)) ? user_trailingslashit($new_permalink) : $permalink;
}
add_filter('post_type_link', 'pm_append_course_name', 150, 3);