Tile.cs

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

public class Tile : MonoBehaviour
{
    [SerializeField] private GameObject _body;

    private Renderer _bodyRend;

    private Unit _occupant;
    public Unit Occupant => _occupant;

    private Grid grid;
    private int x;
    private int y;

    public int X => x;
    public int Y => y;
    private bool isWalkable;
    private bool isOccupied;

    public int gCost;
    public int hCost;
    public int fCost => gCost + hCost;

    public Tile cameFromTile;

    private void Awake()
    {
        _bodyRend = _body.GetComponent<Renderer>();
    }

    public void SetTileData(Grid grid, int x, int y)
    {
        this.grid = grid;
        this.x = x;
        this.y = y;
    }

    public void SetWalkable(bool isWalkable = true)
    {
        this.isWalkable = isWalkable;
    }

    public bool IsWalkable() => isWalkable && !isOccupied;

    public void SetTileMat(Material mat)
    {
        _bodyRend.material = mat;
    }

    public void SetUnitOnTile(Unit unit)
    {
        _occupant = unit;
        isOccupied = _occupant != null;
    }
}