using System;
using System.Collections.Generic;
using System.Linq;
using System.Management;
using System.Text;
using System.Threading.Tasks;
using Zxd.SqlSugar;

namespace ToDoWorker.Helper
{
    public class SeqIdGen
    {
        //起始的时间戳 2020-01-01 00 00 00 开始
        private static long START_STMP = 1577808000000L;

        //每一部分占用的位数
        private static int SEQUENCE_BIT = 12; //序列号占用的位数

        private static int MACHINE_BIT = 6;   //机器标识占用的位数
        private static int DATACENTER_BIT = 3;//数据中心占用的位数

        //每一部分的最大值
        private static long MAX_DATACENTER_NUM = -1L ^ (-1L << DATACENTER_BIT);

        private static long MAX_MACHINE_NUM = -1L ^ (-1L << MACHINE_BIT);
        private static long MAX_SEQUENCE = -1L ^ (-1L << SEQUENCE_BIT);

        //每一部分向左的位移
        private static int MACHINE_LEFT = SEQUENCE_BIT;

        private static int DATACENTER_LEFT = SEQUENCE_BIT + MACHINE_BIT;
        private static int TIMESTMP_LEFT = DATACENTER_LEFT + DATACENTER_BIT;

        private long datacenterId = 1;  //数据中心
        private long machineId = 1;     //机器标识
        private long sequence = 0L; //序列号
        private long lastStmp = -1L;//上一次时间戳

        private static Random r = new Random();

        private static readonly object _locker = new object();
        private static readonly object _Idlocker = new object();
        private static SeqIdGen _instance = (SeqIdGen)null;

        public static SeqIdGen Instance
        {
            get
            {
                if (_instance == null)
                {
                    lock (_locker)
                    {
                        if (_instance == null)
                            _instance = new SeqIdGen();
                    }
                }
                return SeqIdGen._instance;
            }
        }

        private SeqIdGen()
        {
            // SeqIdGenInitRedis();
            SeqIdGenInitConfig(); //从appsetting取
        }

        public void SeqIdGenInitConfig()
        {
            var _machineId = long.Parse(InitConfiguration.GetSection("machineId").Value.ToString());
            var _datacenterId = long.Parse(InitConfiguration.GetSection("datacenterId").Value.ToString());
            SeqIdGenInit(_machineId, _datacenterId);
        }

        /*  public void SeqIdGenInitRedis()
          {
              var cpukey = getCpu();
              var rdc = RedisManager.GetRedisClient2();
              var mechineSeq = rdc.GetValueFromHash("Num:MechineSeq", cpukey);
              if (string.IsNullOrEmpty(mechineSeq))
              {
                  mechineSeq = rdc.IncrementValue("Num:MSeq").ToString();
                  rdc.SetEntryInHash("Num:MechineSeq", cpukey, mechineSeq);
              }
              SeqIdGenInit(long.Parse(mechineSeq), datacenterId);
          }*/

        public string GetDiskVolumeSerialNumber()
        {
            ManagementClass mc = new ManagementClass("Win32_NetworkAdapterConfiguration");
            ManagementObject disk = new ManagementObject("win32_LogHelpericaldisk.deviceid=\"c:\"");
            disk.Get();
            return disk.GetPropertyValue("VolumeSerialNumber").ToString();
        }

        //获得CPU的序列号
        public string getCpu()
        {
            string strCpu = null;
            ManagementClass myCpu = new ManagementClass("win32_Processor");
            ManagementObjectCollection myCpuConnection = myCpu.GetInstances();
            foreach (ManagementObject myObject in myCpuConnection)
            {
                strCpu = myObject.Properties["Processorid"].Value.ToString();
                break;
            }
            return strCpu;
        }

        public void SeqIdGenInit(long cid, long mid)
        {
            if (cid > MAX_DATACENTER_NUM || cid < 0) throw new Exception($"中心Id应在(0,{MAX_DATACENTER_NUM})之间");
            if (mid > MAX_MACHINE_NUM || mid < 0) throw new Exception($"机器Id应在(0,{MAX_MACHINE_NUM})之间");
            datacenterId = cid;
            machineId = mid;
        }

        /// <summary>
        /// 产生下一个ID
        /// </summary>
        /// <returns></returns>
        public long nextId()
        {
            lock (_Idlocker)
            {
                long currStmp = getNewstmp();
                if (currStmp < lastStmp) throw new Exception("时钟倒退，Id生成失败！");

                if (currStmp == lastStmp)
                {
                    //相同毫秒内，序列号自增
                    sequence = (sequence + 1) & MAX_SEQUENCE;
                    //同一毫秒的序列数已经达到最大
                    if (sequence == 0L) currStmp = getNextMill();
                }
                else
                {
                    //不同毫秒内，序列号置为0
                    sequence = 0L;
                }

                lastStmp = currStmp;

                return (currStmp - START_STMP) << TIMESTMP_LEFT       //时间戳部分
                              | datacenterId << DATACENTER_LEFT       //数据中心部分
                              | machineId << MACHINE_LEFT             //机器标识部分
                              | sequence;                             //序列号部分
            }
        }

        private long getNextMill()
        {
            long mill = getNewstmp();
            while (mill <= lastStmp)
            {
                mill = getNewstmp();
            }
            return mill;
        }

        private long getNewstmp()
        {
            return (long)(DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc)).TotalMilliseconds;
        }
    }
}