EnemyMovement.cs

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

public class EnemyMovement : MonoBehaviour
{
    [SerializeField] private float speed;
    [SerializeField] private float rotationSpeed;
    [SerializeField] private float screenBorder;

    private Rigidbody2D rigidbody;
    private PlayerAwarenessController playerAwarenessController;

    private Vector2 targetDirection;

    private float changeDirectionCooldown;
    private Camera camera;

    private void Awake()
    {
        rigidbody = GetComponent<Rigidbody2D>();
        playerAwarenessController = GetComponent<PlayerAwarenessController>();

        targetDirection = transform.up;

        camera = Camera.main;
    }

    private void FixedUpdate()
    {
        UpdateTargetDirection();
        RotateTowardsTarget();
        SetVelocity();
    }

    private void UpdateTargetDirection()
    {
        HandleRandomDirectionChange();
        HandlePlayerTargeting();
        HandleEnemyOffScreen();
    }

    private void HandleRandomDirectionChange()
    {
        changeDirectionCooldown -= Time.deltaTime;

        if (changeDirectionCooldown <= 0)
        {
            float angleChange = Random.Range(-90f, 90f);
            UnityEngine.Quaternion rotation = UnityEngine.Quaternion.Euler(0, 0, angleChange);

            targetDirection = rotation * targetDirection;

            changeDirectionCooldown = Random.Range(1f, 5f);
        }
    }

    private void HandlePlayerTargeting()
    {
        if (playerAwarenessController.AwareOfPlayer)
        {
            targetDirection = playerAwarenessController.DirectionTopPlayer;
        }
    }

    private void HandleEnemyOffScreen()
    {

        UnityEngine.Vector2 screenPosition = camera.WorldToScreenPoint(transform.position);

        if ((screenPosition.x < screenBorder && targetDirection.x < 0) || (screenPosition.x > camera.pixelWidth - screenBorder && targetDirection.x > 0))
        {
            targetDirection = new UnityEngine.Vector2(-targetDirection.x, targetDirection.y);

        }
         if ((screenPosition.y < screenBorder && targetDirection.y < 0) || (screenPosition.y > camera.pixelHeight - screenBorder && targetDirection.y > 0))
        {
            targetDirection = new UnityEngine.Vector2(targetDirection.x, -targetDirection.y);

        }

    }

    private void RotateTowardsTarget()
    {
        float angle = Mathf.Atan2(targetDirection.y, targetDirection.x) * Mathf.Rad2Deg - 90f;
        UnityEngine.Quaternion targetRotation = UnityEngine.Quaternion.Euler(0, 0, angle);
        rigidbody.MoveRotation(Mathf.LerpAngle(rigidbody.rotation, targetRotation.eulerAngles.z, rotationSpeed * Time.deltaTime));
    }

    private void SetVelocity()
    {
        rigidbody.velocity = targetDirection * speed;
    }
}