function llms_get_permalink_structure() {
	$saved_permalinks = (array) get_option( 'llms_permalinks', array() );

	$permalinks = wp_parse_args(
		// Remove false or empty entries so we can use the default values.
		array_filter( $saved_permalinks ),
		array(
			'course_base'               => _x( 'course', 'course url slug', 'lifterlms' ),
			'courses_base'              => _x( 'courses', 'course archive url slug', 'lifterlms' ),
			'memberships_base'          => _x( 'memberships', 'membership archive url slug', 'lifterlms' ),
			'lesson_base'               => _x( 'lesson', 'lesson url slug', 'lifterlms' ),
			'quiz_base'                 => _x( 'quiz', 'quiz url slug', 'lifterlms' ),
			'certificate_template_base' => _x( 'certificate-template', 'slug', 'lifterlms' ),
			'certificate_base'          => _x( 'certificate', 'slug', 'lifterlms' ),
			'course_category_base'      => _x( 'course-category', 'slug', 'lifterlms' ),
			'course_tag_base'           => _x( 'course-tag', 'slug', 'lifterlms' ),
			'course_track_base'         => _x( 'course-track', 'slug', 'lifterlms' ),
			'course_difficulty_base'    => _x( 'course-difficulty', 'slug', 'lifterlms' ),
			'membership_category_base'  => _x( 'membership-category', 'slug', 'lifterlms' ),
			'membership_tag_base'       => _x( 'membership-tag', 'slug', 'lifterlms' ),
		)
	);

	array_filter( $permalinks, 'untrailingslashit' );

	if ( $saved_permalinks !== $permalinks ) {
		update_option( 'llms_permalinks', $permalinks );
	}

	return $permalinks;
}