/// <summary>
/// Shows + AltShows all the planets on a side, that is next to view squares when moved in given direction.
/// Hides + AltHides all the planets on a side, that is next to view squares when moved in opposite direction.
/// </summary>
public State Move(Direction direction)
{
var side = direction.ToSide();
var delta = direction.ToPositionDelta();
var offset = Math.Min(delta.X + delta.Y, 0);
_spaceGrid.Traverse(_regView, side, offset < 0 ? _planets.Show : _planets.Hide, offset);
_spaceGrid.Traverse(_regView, side, offset < 0 ? _planets.Hide : _planets.Show, offset + _regView.Size);
_spaceGrid.Traverse(_altView, side, offset < 0 ? _planets.AltShow : _planets.AltHide, offset);
_spaceGrid.Traverse(_altView, side, offset < 0 ? _planets.AltHide : _planets.AltShow,
offset + _altView.Size);
_altView = _altView.Shift(delta);
_regView = _regView.Shift(delta);
_playerPosition += delta;
_tilesManager.OnViewChanged(_altView);
return(CurrentState());
}
