ModernUO/Projects/Scripts/Items/Misc/EffectItem.cs

using System;
using System.Collections.Generic;

namespace Server.Items
{
  public class EffectItem : Item
  {
    private static List<EffectItem> m_Free = new List<EffectItem>(); // List of available EffectItems

    public static readonly TimeSpan DefaultDuration = TimeSpan.FromSeconds(5.0);

    private EffectItem() : base(1) // nodraw
      =>
        Movable = false;

    public EffectItem(Serial serial) : base(serial)
    {
    }

    public override bool Decays => true;

    public static EffectItem Create(Point3D p, Map map, TimeSpan duration)
    {
      EffectItem item = null;

      for (int i = m_Free.Count - 1; item == null && i >= 0; --i) // We reuse new entries first so decay works better
      {
        EffectItem free = m_Free[i];

        m_Free.RemoveAt(i);

        if (!free.Deleted && free.Map == Map.Internal)
          item = free;
      }

      if (item == null)
        item = new EffectItem();
      else
        item.ItemID = 1;

      item.MoveToWorld(p, map);
      item.BeginFree(duration);

      return item;
    }

    public void BeginFree(TimeSpan duration)
    {
      new FreeTimer(this, duration).Start();
    }

    public override void Serialize(GenericWriter writer)
    {
      base.Serialize(writer);

      writer.Write(0); // version
    }

    public override void Deserialize(GenericReader reader)
    {
      base.Deserialize(reader);

      int version = reader.ReadInt();

      Delete();
    }

    private class FreeTimer : Timer
    {
      private EffectItem m_Item;

      public FreeTimer(EffectItem item, TimeSpan delay) : base(delay)
      {
        m_Item = item;
        Priority = TimerPriority.OneSecond;
      }

      protected override void OnTick()
      {
        m_Item.Internalize();

        m_Free.Add(m_Item);
      }
    }
  }
}