private void Border_MouseEnter(object sender, MouseEventArgs e)
        {
            Border b      = sender as Border;
            var    square = b.DataContext as ChessSquare;
            var    vm     = FindResource("vm") as ChessViewModel;
            var    cs     = vm.hasSelected();

            if (cs == null)
            {
                return;
            }

            else
            {
                BoardPosition bp = cs.Position;
                ChessMove     cm = new ChessMove(bp, square.Position);
                foreach (var x in vm.PossibleMoves)
                {
                    if (cm.Equals(x))
                    {
                        square.IsHovered = true;
                    }
                }
            }
        }