ScienceLab.TypesOfMotion/Assets/Scripts/CarPatrol.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;

public class CarPatrol : MonoBehaviour
{
    [Header("Waypoints")]
    [SerializeField] private Transform[] waypoints;

    [Header("Movement")]
    [SerializeField] private float patrolSpeed = 5f;
    [SerializeField] private float chaseSpeed = 12f;
    [SerializeField] private float acceleration = 3f;
    [SerializeField] private float rotationSpeed = 6f;

    [Header("Detection")]
    [SerializeField] private float detectionDistance = 20f;

    [Header("Siren Reference")]
    [SerializeField] private PoliceSiren siren;

    private Transform _player;
    private int _currentWaypointIndex;
    private float _currentSpeed;
    private bool _isChasing;

    void Start()
    {
        _player = GameObject.FindGameObjectWithTag("Player")?.transform;

        _currentSpeed = patrolSpeed;

        if (siren != null)
            siren.isSirenOn = false;
    }

    void Update()
    {
        if (_player == null || waypoints.Length == 0) return;

        DetectPlayer();

        if (_isChasing)
            ChasePlayer();
        else
            Patrol();
    }

    private void Patrol()
    {
        _currentSpeed = patrolSpeed;

        Vector3 target = waypoints[_currentWaypointIndex].position;

        MoveTowards(target);
        RotateTowards(target);

        if (Vector3.Distance(transform.position, target) < 0.5f)
        {
            _currentWaypointIndex++;
            if (_currentWaypointIndex >= waypoints.Length)
                _currentWaypointIndex = 0;
        }
    }

    private void ChasePlayer()
    {
        _currentSpeed = Mathf.MoveTowards(
            _currentSpeed,
            chaseSpeed,
            acceleration * Time.deltaTime
        );

        MoveTowards(_player.position);
        RotateTowards(_player.position);
    }

    private void DetectPlayer()
    {
        if (_player == null) return;

        Vector3 toPlayer = _player.position - transform.position;

        float distance = toPlayer.magnitude;
        if (distance > detectionDistance)
        {
            StopChase();
            return;
        }

        Vector3 direction = toPlayer.normalized;
        float dot = Vector3.Dot(transform.forward, direction);
        if (dot < 0.5f)
        {
            StopChase();
            return;
        }

        float lateralDistance = Vector3.Cross(transform.forward, toPlayer).magnitude;

        if (lateralDistance > 2f)   
        {
            StopChase();
            return;
        }

        StartChase();
    }

    private void StartChase()
    {
        if (_isChasing) return;

        _isChasing = true;

        if (siren != null)
            siren.isSirenOn = true;
    }

    private void StopChase()
    {
        if (!_isChasing) return;

        _isChasing = false;
        _currentSpeed = patrolSpeed;

        if (siren != null)
            siren.isSirenOn = false;
    }

    private void MoveTowards(Vector3 target)
    {
        Vector3 targetPos = new Vector3(target.x, transform.position.y, target.z);
        Vector3 direction = (targetPos - transform.position).normalized;

        transform.position += direction * _currentSpeed * Time.deltaTime;
    }

    private void RotateTowards(Vector3 target)
    {
        Vector3 direction = new Vector3(
            target.x - transform.position.x,
            0f,
            target.z - transform.position.z
        );

        if (direction == Vector3.zero) return;

        Quaternion targetRotation = Quaternion.LookRotation(direction);

        transform.rotation = Quaternion.Slerp(
            transform.rotation,
            targetRotation,
            rotationSpeed * Time.deltaTime
        );
    }

    private void OnCollisionEnter(Collision collision)
    {

        if (collision.gameObject.CompareTag("Player"))
        {
            SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex);
        }
    }

}