using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.IdentityModel.Tokens.Jwt;
using System.Linq;
using System.Security.Claims;
using System.Threading.Tasks;
using VOL.Core.CacheManager;
using VOL.Core.DBManager;
using VOL.Core.Extensions;
using VOL.Core.Extensions.AutofacManager;
using VOL.Entity;
using VOL.Entity.DomainModels;

namespace VOL.Core.ManageUser
{
    public class UserContext
    {
        /// <summary>
        /// 为了尽量减少redis或Memory读取,保证执行效率,将UserContext注入到DI，
        /// 每个UserContext的属性至多读取一次redis或Memory缓存从而提高查询效率
        /// </summary>
        public static UserContext Current
        {
            get
            {
                return Context.RequestServices.GetService(typeof(UserContext)) as UserContext;
            }
        }

        private static Microsoft.AspNetCore.Http.HttpContext Context
        {
            get
            {
                return Utilities.HttpContext.Current;
            }
        }
        private static ICacheService CacheService
        {
            get { return GetService<ICacheService>(); }
        }

        private static T GetService<T>() where T : class
        {
            return AutofacContainerModule.GetService<T>();
        }

        public UserInfo UserInfo
        {
            get
            {
                if (_userInfo != null)
                {
                    return _userInfo;
                }
                return GetUserInfo(UserId).Result;
            }
        }

        private UserInfo _userInfo { get; set; }

        /// <summary>
        /// 角色ID为1的默认为超级管理员
        /// </summary>
        public bool IsSuperAdmin
        {
            get { return this.RoleId == 1; }
        }
        /// <summary>
        /// 角色ID为1的默认为超级管理员
        /// </summary>
        public static bool IsRoleIdSuperAdmin(int roleId)
        {
            return roleId == 1;
        }

        public async Task<UserInfo> GetUserInfo(int userId)
        {
            if (_userInfo != null) return _userInfo;
            if (userId <= 0)
            {
                _userInfo = new UserInfo();
                return _userInfo;
            }
            string key = userId.GetUserIdKey();
            _userInfo = CacheService.Get<UserInfo>(key);
            if (_userInfo != null && _userInfo.User_Id > 0) return _userInfo;

            _userInfo = await DBServerProvider.DbContext.Set<Sys_User>()
                .Where(x => x.User_Id == userId).Select(s => new UserInfo()
                {
                    User_Id = userId,
                    Role_Id = s.Role_Id.GetInt(),
                    RoleName = s.RoleName,
                    Token = s.Token,
                    UserName = s.UserName,
                    UserTrueName = s.UserTrueName,
                    Enable = s.Enable
                }).FirstOrDefaultAsync();

            if (_userInfo != null && _userInfo.User_Id > 0)
            {
                CacheService.AddObject(key, _userInfo);
            }
            return _userInfo;
        }

        /// <summary>
        /// 获取角色权限时通过安全字典锁定的角色id
        /// </summary>
        private static ConcurrentDictionary<string, object> objKeyValue = new ConcurrentDictionary<string, object>();

        /// <summary>
        /// 角色权限的版本号
        /// </summary>
        private static readonly Dictionary<int, string> rolePermissionsVersion = new Dictionary<int, string>();

        /// <summary>
        /// 每个角色ID对应的菜单权限（已做静态化处理）
        /// 每次获取权限时用当前服务器的版本号与redis/memory缓存的版本比较,如果不同会重新刷新缓存
        /// </summary>
        private static readonly Dictionary<int, List<Permissions>> rolePermissions = new Dictionary<int, List<Permissions>>();


        /// <summary>
        /// 获取用户所有的菜单权限
        /// </summary>

        public List<Permissions> Permissions
        {
            get
            {
                return GetPermissions(RoleId);
            }
        }

        /// <summary>
        /// 获取单个表的权限
        /// </summary>
        /// <param name="tableName"></param>
        /// <returns></returns>
        public Permissions GetPermissions(string tableName)
        {
            return GetPermissions(RoleId).Where(x => x.TableName == tableName).FirstOrDefault();
        }

        /// <summary>
        /// 自定条件查询权限
        /// </summary>
        /// <param name="func"></param>
        /// <returns></returns>
        public Permissions GetPermissions(Func<Permissions, bool> func)
        {
            return GetPermissions(RoleId).Where(func).FirstOrDefault();
        }

        private List<Permissions> ActionToArray(List<Permissions> permissions)
        {
            permissions.ForEach(x =>
            {
                try
                {
                    x.UserAuthArr = string.IsNullOrEmpty(x.UserAuth)
                    ? new string[0]
                    : x.UserAuth.Split(",");
                }
                catch { }
                finally
                {
                    if (x.UserAuthArr == null)
                    {
                        x.UserAuthArr = new string[0];
                    }
                }
            });
            return permissions;
        }
        private List<Permissions> MenuActionToArray(List<Permissions> permissions)
        {
            permissions.ForEach(x =>
            {
                try
                {
                    x.UserAuthArr = string.IsNullOrEmpty(x.UserAuth)
                    ? new string[0]
                    : x.UserAuth.DeserializeObject<List<Sys_Actions>>().Select(s => s.Value).ToArray();
                }
                catch { }
                finally
                {
                    if (x.UserAuthArr == null)
                    {
                        x.UserAuthArr = new string[0];
                    }
                }
            });
            return permissions;
        }
        public List<Permissions> GetPermissions(int roleId)
        {
            if (IsRoleIdSuperAdmin(roleId))
            {
                var permissions = DBServerProvider.DbContext.Set<Sys_Menu>().Where(x => x.Enable == 1).Select(a => new Permissions
                {
                    Menu_Id = a.Menu_Id,
                    ParentId = a.ParentId,
                    TableName = a.TableName ?? "",
                    //MenuAuth = a.Auth,
                    UserAuth = a.Auth,
                }).ToList();
                return MenuActionToArray(permissions);
            }
            ICacheService cacheService = CacheService;
            string roleKey = roleId.GetRoleIdKey();

            //角色有缓存，并且当前服务器的角色版本号与redis/memory缓存角色的版本号相同直接返回静态对象角色权限
            string currnetVeriosn = "";
            if (rolePermissionsVersion.TryGetValue(roleId, out currnetVeriosn)
                && currnetVeriosn == cacheService.Get(roleKey))
            {
                return rolePermissions.ContainsKey(roleId) ? rolePermissions[roleId] : new List<Permissions>();
            }

            //锁定每个角色，通过安全字典减少锁粒度，否则多个同时角色获取缓存会导致阻塞
            object objId = objKeyValue.GetOrAdd(roleId.ToString(), new object());
            //锁定每个角色
            lock (objId)
            {
                if (rolePermissionsVersion.TryGetValue(roleId, out currnetVeriosn)
                    && currnetVeriosn == cacheService.Get(roleKey))
                {
                    return rolePermissions.ContainsKey(roleId) ? rolePermissions[roleId] : new List<Permissions>();
                }

                //没有redis/memory缓存角色的版本号或与当前服务器的角色版本号不同时，刷新缓存
                var dbContext = DBServerProvider.DbContext;
                List<Permissions> _permissions = (from a in dbContext.Set<Sys_Menu>()
                                                  join b in dbContext.Set<Sys_RoleAuth>()
                                                  on a.Menu_Id equals b.Menu_Id
                                                  where b.Role_Id == roleId //&& a.ParentId > 0
                                                  && b.AuthValue != ""
                                                  orderby a.ParentId
                                                  select new Permissions
                                                  {
                                                      Menu_Id = a.Menu_Id,
                                                      ParentId = a.ParentId,
                                                      TableName = a.TableName ?? "",
                                                      MenuAuth = a.Auth,
                                                      UserAuth = b.AuthValue ?? ""
                                                  }).ToList();
                ActionToArray(_permissions);
                string _version = cacheService.Get(roleKey);
                //生成一个唯一版本号标识
                if (_version == null)
                {
                    _version = DateTime.Now.ToString("yyyyMMddHHMMssfff");
                    //将版本号写入缓存
                    cacheService.Add(roleKey, _version);
                }
                //刷新当前服务器角色的权限
                rolePermissions[roleId] = _permissions;

                //写入当前服务器的角色最新版本号
                rolePermissionsVersion[roleId] = _version;
                return _permissions;
            }

        }

        /// <summary>
        /// 判断是否有权限
        /// </summary>
        /// <param name="tableName"></param>
        /// <param name="authName"></param>
        /// <param name="roleId"></param>
        /// <returns></returns>
        public bool ExistsPermissions(string tableName, string authName, int roleId = 0)
        {
            if (roleId <= 0) roleId = RoleId;
            tableName = tableName.ToLower();
            authName = authName.ToLower();
            return GetPermissions(roleId).Any(x => x.TableName == tableName && x.UserAuthArr.Contains(authName));
        }

        public int UserId
        {
            get
            {
                //   if (!Context.User.Identity.IsAuthenticated)  return 0;
                return (Context.User.FindFirstValue(JwtRegisteredClaimNames.Jti)
                    ?? Context.User.FindFirstValue(ClaimTypes.NameIdentifier)).GetInt();
            }
        }

        public string UserName
        {
            get { return UserInfo.UserName; }
        }

        public string UserTrueName
        {
            get { return UserInfo.UserTrueName; }
        }

        public string Token
        {
            get { return UserInfo.Token; }
        }

        public int RoleId
        {
            get { return UserInfo.Role_Id; }
        }

        public void LogOut(int userId)
        {
            CacheService.Remove(userId.GetUserIdKey());
        }
    }
}