Cell.cs

using System;
using MessagePack;

namespace Simulation.Features.Buildings
{
    [Serializable]
    [MessagePackObject]
    public readonly struct Cell : IEquatable<Cell>, IComparable<Cell>
    {
        [Key(0)] public readonly int x;
        [Key(1)] public readonly int y;
        private readonly int _hashCode;

        public override string ToString() => $"Cell(x={x}, y={y})";

        public Cell(int x, int y)
        {
            this.x = x;
            this.y = y;
            _hashCode = HashUtils.CombineHashCodes(x.GetHashCode(), y.GetHashCode());
        }

        public bool Equals(Cell other)
        {
            return x == other.x && y == other.y;
        }

        public override bool Equals(object obj)
        {
            return !ReferenceEquals(null, obj) && Equals((Cell)obj);
        }

        public static bool operator !=(Cell a, Cell b)
        {
            return !a.Equals(b);
        }

        public static bool operator ==(Cell a, Cell b)
        {
            return a.Equals(b);
        }

        public static Cell operator +(Cell a, Cell b)
        {
            return new Cell(a.x + b.x, a.y + b.y);
        }

        public override int GetHashCode() => _hashCode;

        public int CompareTo(Cell other)
        {
            return _hashCode.CompareTo(other._hashCode);
        }
    }

    public static class CellRelativePositionExtensions
    {
        public static Cell Above(this Cell cell)
        {
            return new Cell(cell.x, cell.y + 1);
        }

        public static Cell Below(this Cell cell)
        {
            return new Cell(cell.x, cell.y - 1);
        }

        public static Cell Left(this Cell cell)
        {
            return new Cell(cell.x - 1, cell.y);
        }

        public static Cell Right(this Cell cell)
        {
            return new Cell(cell.x + 1, cell.y);
        }
    }
}