/***************************************************************************
 *                               BufferPool.cs
 *                            -------------------
 *   begin                : May 1, 2002
 *   copyright            : (C) The RunUO Software Team
 *   email                : info@runuo.com
 *
 *   $Id$
 *
 ***************************************************************************/

/***************************************************************************
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 ***************************************************************************/

using System.Collections.Generic;

namespace Server.Network
{
  public class BufferPool
  {
    private int m_BufferSize;

    private Queue<byte[]> m_FreeBuffers;

    private int m_InitialCapacity;

    private int m_Misses;

    private string m_Name;

    public BufferPool(string name, int initialCapacity, int bufferSize)
    {
      m_Name = name;

      m_InitialCapacity = initialCapacity;
      m_BufferSize = bufferSize;

      m_FreeBuffers = new Queue<byte[]>(initialCapacity);

      for (int i = 0; i < initialCapacity; ++i)
        m_FreeBuffers.Enqueue(new byte[bufferSize]);

      lock (Pools)
      {
        Pools.Add(this);
      }
    }

    public static List<BufferPool> Pools{ get; set; } = new List<BufferPool>();

    public void GetInfo(out string name, out int freeCount, out int initialCapacity, out int currentCapacity,
      out int bufferSize, out int misses)
    {
      lock (this)
      {
        name = m_Name;
        freeCount = m_FreeBuffers.Count;
        initialCapacity = m_InitialCapacity;
        currentCapacity = m_InitialCapacity * (1 + m_Misses);
        bufferSize = m_BufferSize;
        misses = m_Misses;
      }
    }

    public byte[] AcquireBuffer()
    {
      lock (this)
      {
        if (m_FreeBuffers.Count > 0)
          return m_FreeBuffers.Dequeue();

        ++m_Misses;

        for (int i = 0; i < m_InitialCapacity; ++i)
          m_FreeBuffers.Enqueue(new byte[m_BufferSize]);

        return m_FreeBuffers.Dequeue();
      }
    }

    public void ReleaseBuffer(byte[] buffer)
    {
      if (buffer == null)
        return;

      lock (this)
      {
        m_FreeBuffers.Enqueue(buffer);
      }
    }

    public void Free()
    {
      lock (Pools)
      {
        Pools.Remove(this);
      }
    }
  }
}