protected function get_output() {

		$course  = new LLMS_Course( $this->get_attribute( 'course_id' ) );
		$student = llms_get_student();

		$args = array(
			'collapse'        => $this->get_attribute( 'collapse' ),
			'course'          => $course,
			'current_section' => null,
			'current_lesson'  => null,
			'sections'        => array(),
			'student'         => $student,
			'toggles'         => $this->get_attribute( 'toggles' ),
		);

		if ( ! $course ) {
			return '';
		}

		$next_lesson = $student ? llms_get_post( $student->get_next_lesson( $course->get( 'id' ) ) ) : false;

		if ( 'lesson' === get_post_type() ) {
			$args['current_lesson'] = get_the_ID();
		}

		// show only the current section
		if ( $next_lesson && 'current_section' === $this->get_attribute( 'outline_type' ) ) {

			$section = llms_get_post( $next_lesson->get( 'parent_section' ) );

			$args['sections'][]      = $section;
			$args['current_section'] = $section->get( 'id' );

		} else {

			if ( 'lesson' === get_post_type() ) {
				$lesson = llms_get_post( get_the_ID() );
			} else {
				$lesson = $next_lesson;
			}

			$args['sections']        = $course->get_sections();
			$args['current_section'] = ! empty( $lesson ) && is_a( $lesson, 'LLMS_Post_Model' ) ? $lesson->get( 'parent_section' ) : false;

		}

		ob_start();
		llms_get_template( 'course/outline-list-small.php', $args );
		return ob_get_clean();

	}