using UnityEngine;
using UnityEngine.AI;

public class WanderingAIWaypointsOld : MonoBehaviour
{
    public Transform[] waypoints;
    public float wanderTimer;
    public float targetScattering = 5.0f; //Streuung

    private Animator anim;
    private NavMeshAgent agent;

    private float timer;
    private int prevWP = -1;
    private Vector3 target;

    // Use this for initialization
    void Start()
    {
        agent = this.GetComponent<NavMeshAgent>();
        anim = this.GetComponent<Animator>();
        anim.SetBool("isWalking", false);
        anim.SetBool("isIdle", true);

        timer = wanderTimer;
    }

    private void FixedUpdate()
    {
        timer += Time.deltaTime;
        
        if (timer >= wanderTimer)
        {
            if (waypoints.Length == 0) return;
            
            int currentWP = Random.Range(0, waypoints.Length);
            // Until previous and current WP are no longer the same, otherwise double waiting time for same WP
            while(prevWP == currentWP)
                currentWP = Random.Range(0, waypoints.Length);
            prevWP = currentWP;

            target = checkTarget(waypoints[currentWP].transform.position, targetScattering);
            if(target.x != float.PositiveInfinity)
            {
                if (agent.isActiveAndEnabled)
                    agent.SetDestination(target);
            
                anim.SetBool("isWalking", true);
                anim.SetBool("isIdle", false);
                timer = 0;
            }
            else
            {
                timer = wanderTimer;
            }
        }
        else
        {
            // if x and z coordinates of newPos are the same as the position, humans reached destination and idle animation can start
            if (target.x == transform.position.x && target.z == transform.position.z)
            {
                anim.SetBool("isWalking", false);
                anim.SetBool("isIdle", true);
            }
        }
    }

    public static Vector3 checkTarget(Vector3 target, float dist)
    {
        Vector3 modifiedTarget = Random.insideUnitSphere * dist + target;
        // SamplePosition also checks the y axis. However, this is not relevant for me, so valid positions (x & z) are also discarded.
        // -3.6f is the only valid entry for y
        modifiedTarget = new Vector3(modifiedTarget.x, 0f, modifiedTarget.z);

        NavMeshHit navHit;
        NavMesh.SamplePosition(modifiedTarget, out navHit, 1.0f, -1);

        return navHit.position;
    }
}