using UnityEngine;
using UnityEngine.InputSystem;

public class PlayerMovement : MonoBehaviour
{
    [SerializeField] private float speed = 2f;
    private Rigidbody2D body;

    private void Awake() => body = GetComponent<Rigidbody2D>();

    private void Update()
    {
        Keyboard kb = Keyboard.current;

        float hor = 0f;
        if (kb.dKey.isPressed || kb.rightArrowKey.isPressed) hor += 1f;
        if (kb.aKey.isPressed || kb.leftArrowKey.isPressed)  hor -= 1f;

        float ver = 0f;
        if (kb.wKey.isPressed || kb.upArrowKey.isPressed)    ver += 1f;
        if (kb.sKey.isPressed || kb.downArrowKey.isPressed)  ver -= 1f;

        Vector2 move = new Vector2(hor, ver).normalized;
        body.linearVelocity = move * speed;
    }
}

using UnityEngine;
using UnityEngine.InputSystem;

public class SharkRotation : MonoBehaviour
{
    private SpriteRenderer sprite;

    private void Awake() => sprite = GetComponent<SpriteRenderer>();

    private void Update()
    {
        Vector3 mouseScreen = Mouse.current.position.ReadValue();
        Vector3 mouseWorld = Camera.main.ScreenToWorldPoint(mouseScreen);
        Vector3 look = mouseWorld - transform.position;
        look.z = 0f;

        transform.right = look;        // нос смотрит на курсор

        if (look.x < 0f)               // курсор слева — акула вверх ногами
            sprite.flipY = true;
        else
            sprite.flipY = false;
    }
}

using UnityEngine;

public class CameraFollow : MonoBehaviour
{
    [SerializeField] private Transform target;    // за кем ехать
    [SerializeField] private float smooth = 4f;   // насколько плавно

    private void LateUpdate()
    {
        if (target == null) return;

        Vector3 goal = target.position;
        goal.z = transform.position.z;            // камеру по Z не двигаем!

        transform.position = Vector3.Lerp(transform.position, goal, smooth * Time.deltaTime);
    }
}