How to change a variable in a shared script, without affecting all the other game objects that share that script?

Question

Ive been at it all day trying to solve this, because I dont want to make a separate script for every bullet, instead I want to have a single EnemyBulletMovement script, that can move each bullet in a different way, depending on the BulletType int that I feed into it when I instantiate it.

The problem is that if I fire multiple bullets at the same time, they will all change BulletType as soon as another bullet is instantiated, because they are all sharing the same script.

My goal is to have all bullets have a private script, but no matter what I try the variable will still be changed for all active bullets every time I try to change it for just one of them.

EnemyController script that Instantiates the bullets and gives them a BulletType value:

 GameObject enemyBullet = ObjectPooler.SharedInstance.GetPooledEnemyBullet();
        if (enemyBullet != null)
        {
            Quaternion rotationAmount = Quaternion.Euler(0, 0, 0);
            Quaternion postRotation = transform.rotation * rotationAmount;
            enemyBullet.transform.position = transform.position;
            enemyBullet.transform.rotation = postRotation;
            enemyBullet.SetActive(true);
            enemyBullet.GetComponent<EnemyBulletMovement>().SetBullet(2);

        }
        GameObject enemyBullet2 = ObjectPooler.SharedInstance.GetPooledEnemyBullet();
        if (enemyBullet2 != null)
        {
            Quaternion rotationAmount = Quaternion.Euler(0, 3, 0);
            Quaternion postRotation = transform.rotation * rotationAmount;
            enemyBullet2.transform.position = transform.position;
            enemyBullet2.transform.rotation = postRotation;
            enemyBullet2.SetActive(true);
            enemyBullet2.GetComponent<EnemyBulletMovement>().SetBullet(0);
        }

Shared EnemyBulletMotion script, that gets the bulletType from the above script. This is the problem:

public void SetBullet(int typeIndex)
{
    bulletType = typeIndex;
    Debug.Log(bulletType);
}
private void BulletMotion()
{
    
    if (bulletType == 0)
    {
        rb.velocity = pos;
    }
    if (bulletType == 1)
    {
        axis = Mathf.Sin(Time.deltaTime * -frequency) * magnitude * transform.up;  // Up down Wave motion
        transform.Rotate(Vector3.forward * sideMag);                               // Side Sway Motion (+ Wave = Spiral Motion)
        rb.velocity = pos + axis;                                                  // Combine all Motions
    }
    if (bulletType == 2)
    {
        Debug.Log("Shootin");
        axis = Mathf.Sin(Time.deltaTime * -frequency) * magnitude * transform.up;  // Up down Wave motion
        transform.Rotate(Vector3.forward * -sideMag);                              // Side Sway Motion (+ Wave = Spiral Motion)
        rb.velocity = pos + axis;                                                  // Combine all Motions
    }

}

EDIT: This Debug Shootin never appears in my console though, so maybe the bulletType is not being read correctly here after all? For Clarification, the first Debug.Log(bulletType); return a 0 or a 2 so it is working. But the second Debug.Log("Shootin"); does not get printed, ever.

I tried private, static, and made an Instance out of the whole EnemyBulletMovement script but nothing works.

When I debug this code, the script works, the bulletType will change from 2 to 0 and back, but when it does it will change both bullets, so both will fly the same way, when what I want is to have each bullet follow its own motion. If there is no way to do this I will have to create a separate script for each bulletmotion, but im only showing 2 here and I already have a lot of them, thats why I wanted to try this out and make it work with if statements and then use case statements later.

EDIT: Added ObjectPooler script below.

public List<GameObject> pooledEnemyBullets;
public GameObject EnemyBulletToPool;
public int EnemyBulletAmountToPool;
  pooledEnemyBullets = new List<GameObject>();
public static ObjectPooler SharedInstance;

void Awake()
{
    SharedInstance = this;
}


void Start()
{
    for (int i = 0; i < EnemyBulletAmountToPool; i++)
    {
        GameObject obj3 = (GameObject)Instantiate(EnemyBulletToPool);
        obj3.SetActive(false);
        pooledEnemyBullets.Add(obj3);
    }
}
public GameObject GetPooledEnemyBullet()
{
    //1
    for (int i = 0; i < pooledEnemyBullets.Count; i++)
    {
        //2
        if (!pooledEnemyBullets[i].activeInHierarchy)
        {
            return pooledEnemyBullets[i];
        }
    }
    //3   
    return null;
}
}

Answer 1

Bullet type should be declared as private int bulletType. If you declare bullet type as private static int bulletType it will be same for all bullets.

If it is already declared as private int bulletType, then you should check the logic where you use object pooler. You may be processing the same bullet over and over, or processing all bullets in the pool.