ScienceLab.TypesOfMotion/Assets/Scripts/AnimalChase.cs

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

public class AnimalChase : MonoBehaviour
{    public enum AnimalType
    {
        Cat,
        Dog
    }

    public AnimalType animalType;
    public AnimalChase otherAnimal;
    public PlayZone zone;

    public float walkSpeed = 2f;
    public float runSpeed = 4f;
    public float catchDistance = 1.5f;
    public float restTime = 1f;

    private CharacterController _controller;
    private Animator _animator;

    private bool _isChasing;
    private bool _isResting;
    private bool _isRunningAway;

    private Vector3 _targetPoint;

    private float _gravity = -9.8f;
    private float _verticalVelocity;

    private void Awake()
    {
        _controller = GetComponent<CharacterController>();
        _animator = GetComponent<Animator>();
    }

    private void Start()
    {
        if (animalType == AnimalType.Dog)
            StartChasing();
    }

    private void Update()
    {
        if (zone == null || otherAnimal == null)
            return;

        ApplyGravity();

        if (_isResting)
        {
            UpdateAnimator(0f, 0f);
            return;
        }

        if (_isChasing)
        {
            ChaseTarget();
        }
        else if (_isRunningAway)
        {
            RunToPoint();
        }
        else
        {
            UpdateAnimator(0f, 0f);
        }
    }


    private void ChaseTarget()
    {
        MoveTo(otherAnimal.transform.position, runSpeed);

        float dist = Vector3.Distance(transform.position, otherAnimal.transform.position);

        if (dist <= catchDistance)
        {
            StartCoroutine(RestAndSwitch());
        }
    }

    private void RunToPoint()
    {
        MoveTo(_targetPoint, walkSpeed);

        if (Vector3.Distance(transform.position, _targetPoint) < 0.5f)
        {
            _isRunningAway = false;
        }
    }

    private void MoveTo(Vector3 worldTarget, float speed)
    {
        worldTarget = zone.ClampToZone(worldTarget);

        Vector3 dir = worldTarget - transform.position;
        dir.y = 0f;

        float distance = dir.magnitude;

        if (distance < 0.1f)
        {
            UpdateAnimator(0f, 0f);
            return;
        }

        dir.Normalize();

        Vector3 move = dir * speed;
        move.y = _verticalVelocity;

        _controller.Move(move * Time.deltaTime);

        transform.rotation = Quaternion.LookRotation(dir);


        if (speed >= runSpeed * 0.9f)
        {
            UpdateAnimator(1f, 1f);
        }
        else
        {
            UpdateAnimator(1f, 0f);
        }
    }


    private IEnumerator RestAndSwitch()
    {
        _isChasing = false;
        _isResting = true;

        UpdateAnimator(0f, 0f);

        yield return new WaitForSeconds(restTime);

        _isResting = false;

        _targetPoint = zone.GetRandomPoint();
        _isRunningAway = true;

        otherAnimal.StartChasing();
    }

    public void StartChasing()
    {
        _isChasing = true;
        _isRunningAway = false;
        _isResting = false;
    }

    private void UpdateAnimator(float vert, float state)
    {
        _animator.SetFloat("Vert", vert);
        _animator.SetFloat("State", state);
    }

    private void ApplyGravity()
    {
        if (_controller.isGrounded)
        {
            _verticalVelocity = -1f;
        }
        else
        {
            _verticalVelocity += _gravity * Time.deltaTime;
        }
    }
}