ExtruderPiston.cs

using UnityEngine;

public class ExtruderPiston : MonoBehaviour
{
    public GameObject extruder;
    private StateManager stateManager;
    private Vector3 originalPosition;
    private Vector3 endPosition;
    private bool setEndPosition;
    private bool movingForward = true;
    private bool movingBack;
    private bool soundPlayed;

    //! Called by unity engine on start up to initialize variables.
    public void Start()
    {
        stateManager = FindObjectOfType<StateManager>();
        originalPosition = transform.position;
    }

    //! Called once per frame by unity engine.
    public void Update()
    {
        if (!stateManager.Busy())
        {
            if (extruder.GetComponent<Light>().enabled == true)
            {
                float startDistance = Vector3.Distance(transform.position, originalPosition);
                if (startDistance < 1.2f && movingForward == true)
                {
                    if (soundPlayed == false)
                    {
                        extruder.GetComponent<AudioSource>().Play();
                        soundPlayed = true;
                    }
                    transform.position += transform.right * 1.1f * Time.deltaTime;
                }
                else
                {
                    if (setEndPosition == false)
                    {
                        endPosition = transform.position;
                        setEndPosition = true;
                    }
                    movingBack = true;
                    movingForward = false;
                }

                float endDistance = Vector3.Distance(transform.position, endPosition);
                if (endDistance < 1.2f && movingBack == true)
                {
                    if (soundPlayed == true)
                    {
                        soundPlayed = false;
                    }
                    transform.position -= transform.right * 1.1f * Time.deltaTime;
                }
                else
                {
                    setEndPosition = false;
                    movingBack = false;
                    movingForward = true;
                }
            }
        }
    }
}