using System;

    using System.Diagnostics;

    using System.Net;

    using System.Net.Sockets;

    using System.Threading;

    /// <summary>

    ///     ID 生成器

    /// </summary>

    public class IDFactory

    {

        #region Static Fields

        /// <summary>

        /// The factory.

        /// </summary>

        private static IDFactory factory;

        #endregion

        #region Fields

        /// <summary>

        ///     The init millisecond.

        /// </summary>

        private readonly ulong InitMillisecond;

        /// <summary>

        ///     The m watch.

        /// </summary>

        private readonly Stopwatch mWatch = new Stopwatch();

        /// <summary>

        ///     The m current millisecond.

        /// </summary>

        private ulong mCurrentMillisecond;

        /// <summary>

        ///     The m seed.

        /// </summary>

        private byte mSeed;

        #endregion

        #region Constructors and Destructors

        /// <summary>

        ///     Initializes a new instance of the <see cref="IDFactory" /> class.

        /// </summary>

        public IDFactory()

        {

            this.InitMillisecond = (ulong)(DateTime.Now - DateTime.Parse("2015-1-1")).TotalMilliseconds;

            this.mWatch.Restart();

        }

        static IDFactory()

        {

            LoadIPGroup();

        }

        #endregion

        #region Public Properties

        /// <summary>

        ///     Gets or sets the group.

        /// </summary>

        public static byte Group { get; set; }

        #endregion

        #region Public Methods and Operators

        /// <summary>

        ///     生成 ID 种子

        /// </summary>

        /// <returns>返回ID种子。参见<see cref="long" /></returns>

        public static long Create()

        {

            if (factory == null)

            {

                factory = new IDFactory();

            }

            return (long)factory.Next();

        }

        /// <summary>

        ///     获取IP

        /// </summary>

        public static void LoadIPGroup()

        {

            string hostName = Dns.GetHostName();

            IPAddress[] addressList = Dns.GetHostAddresses(hostName);

            foreach (IPAddress ip in addressList)

            {

                if (ip.AddressFamily == AddressFamily.InterNetwork)

                {

                    byte[] data = ip.GetAddressBytes();

                    uint value = BitConverter.ToUInt32(data, );

                    value = value << ;

                    value = value >> ;

                    Group = (byte)value;

                    break;

                }

            }

        }

        /// <summary>

        ///     生成ID种子

        /// </summary>

        /// <returns>

        ///     The <see cref="ulong" />.

        /// </returns>

        public ulong Next()

        {

            ulong result = ;

            var slock = new SpinLock();

            bool gotLock = false;

            try

            {

                while (!gotLock)

                {

                    slock.Enter(ref gotLock);

                    if (gotLock)

                    {

                        ulong cms = (ulong)this.mWatch.Elapsed.TotalMilliseconds + this.InitMillisecond;

                        if (cms != this.mCurrentMillisecond)

                        {

                            this.mSeed = ;

                            this.mCurrentMillisecond = cms;

                        }

                        //result = ((ulong)this.Group << 58) | (this.mCurrentMillisecond << 8) | this.mSeed;

                        //result = ((ulong)Group << 9) | (this.mCurrentMillisecond << 17) | this.mSeed;

                        //result = this.mCurrentMillisecond * 1000000 + (ulong)Group * 1000 + this.mSeed;

                        result = this.mCurrentMillisecond *  + (ulong)Group *  + this.mSeed;

                        this.mSeed++;

                    }

                }

            }

            finally

            {

                if (gotLock)

                {

                    slock.Exit();

                }

            }

            return result;

        }

        #endregion

    }