using System.Runtime.InteropServices;
using JNPF.Common.Cache;
using JNPF.Common.Const;
using JNPF.FriendlyException;
using Yitter.IdGenerator;

namespace JNPF.Common.Security;

/// <summary>
/// 分布式雪花ID帮助类.
/// </summary>
public class SnowflakeIdHelper
{
  // 定义dll路径
  public const string RegWorkerId_DLL_NAME = "lib\\regworkerid_lib_v1.3.1\\yitidgengo.dll";

  // 根据文档定义三个接口

  // 注册一个 WorkerId，会先注销所有本机已注册的记录
  // ip: redis 服务器地址
  // port: redis 端口
  // password: redis 访问密码，可为空字符串“”
  // maxWorkerId: 最大 WorkerId
  [DllImport(RegWorkerId_DLL_NAME, EntryPoint = "RegisterOne", CallingConvention = CallingConvention.Cdecl, ExactSpelling = false)]
  private static extern ushort RegisterOne(string ip, int port, string password, int maxWorkerId);

  // 注销本机已注册的 WorkerId
  [DllImport(RegWorkerId_DLL_NAME, EntryPoint = "UnRegister", CallingConvention = CallingConvention.Cdecl, ExactSpelling = false)]
  private static extern void UnRegister();

  // 检查本地WorkerId是否有效（0-有效，其它-无效）
  [DllImport(RegWorkerId_DLL_NAME, EntryPoint = "Validate", CallingConvention = CallingConvention.Cdecl, ExactSpelling = false)]
  private static extern int Validate(int workerId);

  /// <summary>
  /// 初始化YitId配置
  /// </summary>
  public static void InitYitIdWorker()
  {
    //var option = new IdGeneratorOptions
    //{
    //  WorkerId = 1, //必须 全局唯一,必须 程序设定,理论最大值 2^WorkerIdBitLength-1
    //  //BaseTime = new DateTime(2023, 1, 1, 0, 0, 0, DateTimeKind.Utc), //用生成ID时的系统时间与基础时间的差值(毫秒数)作为生成ID的时间戳
    //  WorkerIdBitLength = 16, //机器码位长,决定 WorkerId 的最大值,默认值6,取值范围 [1, 16]
    //  //SeqBitLength = 4, //序列数位长,默认值6,取值范围 [3, 21](建议不小于4),决定每毫秒基础生成的ID个数
    //  //MinSeqNumber = 5, //最小序列数,默认值5,取值范围 [5, MaxSeqNumber]
    //  //MaxSeqNumber 最大序列数，设置范围 [MinSeqNumber, 2^SeqBitLength-1]，默认值0
    //};
    var option = App.GetConfig<IdGeneratorOptions>("YitId");
    if (option.WorkerId == 0)
    {
      CacheOptions _cacheOptions = App.GetConfig<CacheOptions>("Cache", true);
      option.WorkerId = RegisterOne(_cacheOptions.ip, _cacheOptions.port, _cacheOptions.password, 63);
    }
    YitIdHelper.SetIdGenerator(option);
  }

  /// <summary>
  /// 生成ID.
  /// </summary>
  /// <returns></returns>
  public static string NextId()
  {
    return YitIdHelper.NextId().ToString();
  }
}