Enemy Approaching player and then stopping in front??

Hey guys need a quick bit of help. My game is a star fox clone essentally so maybe that'll give you an idea of what I'm trying to do. I was messing around with some code. I wanted the enemy to approach the player and when he gets within the "safe distance" to turn in the opposite direction and match the players speed and then later start attackign but one thing at a time!

 var player:GameObject;

var safeDistance = 20; //How close the player can get

public var speed =10;

function Update()

{

var player = GameObject.Find("Sphere(Clone)");

//transform.LookAt (player.transform); //you look at player with this

//write other codes here

var distanceToPlayer = Vector3.Distance(this.transform.position, player.transform.position);

// this checks to see if the player is too close then runs the fire function

if(distanceToPlayer <= safeDistance){

transform.Translate (Vector3(0,0,2));

print("forward");

}

else{

transform.Translate (Vector3(0,0,Random.Range(-1,-10))); //moves with speed in local z and you are looking toward him so you move toward the player

print("backwards");

}

}

function OnCollisionEnter(collision : Collision)

{

Destroy(gameObject);

}

So what am I doing wrong...?

:(

Thanks in advance guys!