Do you know any patrolling AI script for a navmesh?

I would like to have a script that allows the enemy to patroll on a navmesh, but as soon as he “sees” the player, another script gets activated (the chasing script that i have already made). It would be cool if the script had the function that if the player is (for example) 5 meters away, then the chasing script is deactivating (false) again until he sees the player again…

Something like this:

using UnityEngine;
using System.Collections;

public class EnemyScript : MonoBehaviour {
	public GameObject player;
	public Vector3[] patrolPoints; //Add in inspector
	private int patrolPoint = 0;
	private NavMeshAgent agent;
	void Patrol(){
		if(patrolPoints.Length > 0){
			if(transform.position == patrolPoints[patrolPoint] || Vector3.Distance(transform.position,patrolPoints[patrolPoint])<0.2f){
				patrolPoint++;    //use distance if needed(lower precision)
			if(patrolPoint >= patrolPoints.Length){
				patrolPoint = 0;
	void Attack(){
		//??? your job...
		agent.Stop(); //maybe not needed
		Debug.Log("Whaaaaaaa");	//just to get informed
	void Start() {
		agent = GetComponent<NavMeshAgent>();
	void Update(){
		if(!Physics.Linecast(transform.position,player.transform.position,1)){ //check if we see player by linecasting,move player to another layer so the ray won't hit it. 
		}else {