CatStation/Content.Server/Construction/AnchorOnlyOnStationSystem.cs

using System.Linq;
using Content.Shared.Construction.Components;
using Content.Shared.Station.Systems;
using Robust.Server.GameObjects;

namespace Content.Server.Construction;

public sealed partial class AnchorOnlyOnStationSystem : EntitySystem
{
    [Dependency] private StationSystem _stationSystem = null!;
    [Dependency] private TransformSystem _transform = null!;

    public override void Initialize()
    {
        base.Initialize();

        SubscribeLocalEvent<GridSplitEvent>(OnGridSplit);
    }

    private void OnGridSplit(ref GridSplitEvent args)
    {
        var allGrids = args.NewGrids.ToList();

        var query = AllEntityQuery<AnchorOnlyOnStationComponent, TransformComponent>();
        while (query.MoveNext(out var ent, out var anchorOnlyOnStationComp, out var entXform))
        {
            if (entXform.GridUid == null)
                continue;

            if (!allGrids.Contains(entXform.GridUid.Value))
                continue;

            if (_stationSystem.IsOnStation(ent, anchorOnlyOnStationComp.OnlyCountLargestGrid))
                continue;

            _transform.Unanchor(ent, entXform);
        }
    }
}