/***************************************************************************
 *                               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;
using System.Collections;
using System.Collections.Generic;

namespace Server.Network
{
	public class BufferPool
	{
		private static List<BufferPool> m_Pools = new List<BufferPool>();

		public static List<BufferPool> Pools{ get{ return m_Pools; } set{ m_Pools = value; } }

		private string m_Name;

		private int m_InitialCapacity;
		private int m_BufferSize;

		private int m_Misses;

		private Queue<byte[]> m_FreeBuffers;

		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 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 ( m_Pools )
				m_Pools.Add( this );
		}

		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 ( m_Pools )
				m_Pools.Remove( this );
		}
	}
}