using PixelCrushers.DialogueSystem;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.AI;

public class NahalController : MonoBehaviour
{
    Transform m_PlayerTransform;
    public float m_TargetHeight = 1.8f;
    public float m_followRate = 1.0f;
    NavMeshAgent m_meshAgent;
    NavMeshPath m_path;// = new NavMeshPath();
    int m_currentPathPoint = -1;
    public float m_pathPointDistance = 1f;
    public float m_randomMotionFreq = 1f;
    public float m_randomMotionScale = 0.2f;
    public float m_maxPlayerDist = 5f;
    public float m_minPlayerDist = 2f;
    public float m_minTargetDistFromPlayer = 1f;
    Vector3 m_destinationPoint;
    
    Vector3 m_randShift = Vector3.zero;
    public Transform m_ballTransform;
    public Transform  m_targetTransformWaypoint;
    // Start is called before the first frame update
    public enum State { IDLE, FOLLOW_PLAYER, FOLLOW_PATH }
    public State m_state = State.FOLLOW_PLAYER;
    IEnumerator GenerateRandomShift()
    {
        while (true)
        {
            m_randShift.x = Random.Range(-m_randomMotionScale, m_randomMotionScale);
            m_randShift.y = Random.Range(-m_randomMotionScale, m_randomMotionScale) + m_TargetHeight;
            m_randShift.z = Random.Range(-m_randomMotionScale, m_randomMotionScale);

            yield return new WaitForSeconds(m_randomMotionFreq);
        }
    }
    void Start()
    {
        m_meshAgent = GetComponent<NavMeshAgent>();

        var p =GameObject.FindGameObjectWithTag("Player");
        if (p)
        {
            m_PlayerTransform = p.transform;
        }
        else
        {
            Debug.LogError("Player not found!");
        }
        StartCoroutine(GenerateRandomShift());
    }
    void SetState(State state)
    {
        m_state = state;
    }

    void MoveBallTowards(Vector3 localPos)
    {
        m_ballTransform.localPosition = Vector3.Lerp(localPos, m_ballTransform.localPosition, Mathf.Exp(-Time.deltaTime * m_followRate));

    }

    Vector3 GetPositionNextToPlayer()
    {
        return m_PlayerTransform.position + m_PlayerTransform.right * m_minTargetDistFromPlayer;
    }
    // Update is called once per frame
    void Update()
    {
       // Vector3 currGroundPos = transform.position - Vector3.up * m_TargetHeight;
        Vector3 playerPos = GetPositionNextToPlayer();
        var diff = playerPos - transform.position;
        diff.y = 0f;
        float playerDist = diff.magnitude;
        switch (m_state)
        {
            case State.FOLLOW_PLAYER:
                //m_meshAgent.
                if (!m_meshAgent.hasPath)
                {
                    if (playerDist > m_minPlayerDist)
                    {
                        m_destinationPoint = playerPos;
                        m_meshAgent.SetDestination(m_destinationPoint);
                    }
                }
                else
                {
                    var dist = (playerPos - m_destinationPoint).magnitude;
                    if (dist > m_maxPlayerDist)
                    {
                        m_destinationPoint = playerPos;
                        m_meshAgent.SetDestination(m_destinationPoint);
                    }
                }
                //Vector3 targetPos = m_PlayerTransform.position + Vector3.up * m_TargetHeight + m_randShift;
                //transform.position = Vector3.Lerp(targetPos, transform.position, 0.9f);
               //MoveTowards(targetPos);
                break;
            case State.FOLLOW_PATH:
                if (m_path != null && m_path.status == NavMeshPathStatus.PathComplete)
                {

                    if (m_meshAgent.hasPath)
                    {
                        return;
                    }

                    var currPoint = m_path.corners[m_currentPathPoint];
                    diff = currPoint - transform.position;
                    diff.y = 0f;
                    if (diff.magnitude < m_pathPointDistance && playerDist < m_maxPlayerDist)
                    {
                        m_currentPathPoint++;
                        if (m_currentPathPoint == m_path.corners.Length)
                        {
                            SetState(State.FOLLOW_PLAYER);
                            m_path = null;
                        }
                    }
                    else
                    {
                        m_meshAgent.SetDestination(currPoint);
                        //targetPos = currPoint + Vector3.up * m_TargetHeight + m_randShift;
                       // MoveTowards(targetPos);
                    }

                }
                else
                {
                    m_path = new NavMeshPath();


                    if (m_meshAgent.CalculatePath(m_targetTransformWaypoint.position, m_path))
                    {
                        m_currentPathPoint = 0;
                      
                    }
                    else
                    {
                        SetState(State.FOLLOW_PLAYER);
                    }
                }
                break;
            case State.IDLE:
                break;
        }
        MoveBallTowards(m_randShift);

    }
}