ModernUO/Projects/Scripts/Commands/BoundingBoxPicker.cs

using Server.Targeting;

namespace Server.Commands
{
  public delegate void BoundingBoxCallback(Map map, Point3D start, Point3D end);

  public static class BoundingBoxPicker
  {
    public static void Begin(Mobile from, BoundingBoxCallback callback)
    {
      from.SendMessage("Target the first location of the bounding box.");
      from.Target = new PickTarget(callback);
    }

    private class PickTarget : Target
    {
      private BoundingBoxCallback m_Callback;
      private bool m_First;
      private Map m_Map;
      private Point3D m_Store;

      public PickTarget(BoundingBoxCallback callback) : this(Point3D.Zero, true, null, callback)
      {
      }

      public PickTarget(Point3D store, bool first, Map map, BoundingBoxCallback callback) : base(-1, true, TargetFlags.None)
      {
        m_Store = store;
        m_First = first;
        m_Map = map;
        m_Callback = callback;
      }

      protected override void OnTarget(Mobile from, object targeted)
      {
        if (!(targeted is IPoint3D p))
          return;

        if (p is Item item)
          p = item.GetWorldTop();

        if (m_First)
        {
          from.SendMessage("Target another location to complete the bounding box.");
          from.Target = new PickTarget(new Point3D(p), false, from.Map, m_Callback);
        }
        else if (from.Map != m_Map)
        {
          from.SendMessage("Both locations must reside on the same map.");
        }
        else if (m_Map != null && m_Map != Map.Internal && m_Callback != null)
        {
          Point3D start = m_Store;
          Point3D end = new Point3D(p);

          Utility.FixPoints(ref start, ref end);

          m_Callback(m_Map, start, end);
        }
      }
    }
  }
}