DoorActivator

using UnityEngine;

namespace DefaultNamespace
{
    public class DoorActivator : MonoBehaviour
    {
        private const string Player = "Player";
        private static readonly int Close = Animator.StringToHash("Close");
        private static readonly int Open = Animator.StringToHash("Open");

        public GameObject Canvas;
        public Animator Door;

        private Animator _anim;

        private bool _canOpenDoor;
        private bool _doorIsOpened;

        [SerializeField] private KeyCode _activationKey = KeyCode.E;

        private void Start()
        {
            _anim = Door.GetComponent<Animator>();
        }

        private void Update()
        {
            if (Input.GetKeyDown(_activationKey) && _canOpenDoor && _doorIsOpened)
            {
                _doorIsOpened = !_doorIsOpened;

                if (_doorIsOpened)
                    _anim.SetTrigger(Close);
                else
                    _anim.SetTrigger(Open);

                _doorIsOpened = false;
            }
        }

        private void OnTriggerStay(Collider other)
        {
            if (other.CompareTag(Player))
            {
                Canvas.SetActive(true);

                _canOpenDoor = true;
            }
        }

        private void OnTriggerExit(Collider other)
        {
            if (other.CompareTag(Player))
            {
                Canvas.SetActive(false);

                _canOpenDoor = false;
            }
        }
    }
}