using System;
using System.Collections.Generic;
using System.Linq;
using System.Security.Principal;
using System.Text;
using System.Threading;
using System.Web;
using NewLife.Common;
using NewLife.Model;
using NewLife.Web;
using XCode.Model;
#if !__CORE__
using System.Web.SessionState;
#endif

namespace XCode.Membership
{
    /// <summary>管理提供者接口</summary>
    /// <remarks>
    /// 管理提供者接口主要提供（或统一规范）用户提供者定位、用户查找登录等功能。
    /// 只需要一个实现IManageUser接口的用户类即可实现IManageProvider接口。
    /// IManageProvider足够精简，使得大多数用户可以自定义实现；
    /// 也因为其简单稳定，大多数需要涉及用户与权限功能的操作，均可以直接使用该接口。
    /// </remarks>
    public interface IManageProvider : IServiceProvider
    {
        /// <summary>当前登录用户，设为空则注销登录</summary>
        IManageUser Current { get; set; }

        /// <summary>获取当前用户</summary>
        /// <param name="context"></param>
        /// <returns></returns>
        IManageUser GetCurrent(IServiceProvider context);

        /// <summary>设置当前用户</summary>
        /// <param name="user"></param>
        /// <param name="context"></param>
        void SetCurrent(IManageUser user, IServiceProvider context);

        /// <summary>根据用户编号查找</summary>
        /// <param name="userid"></param>
        /// <returns></returns>
        IManageUser FindByID(Object userid);

        /// <summary>根据用户帐号查找</summary>
        /// <param name="name"></param>
        /// <returns></returns>
        IManageUser FindByName(String name);

        /// <summary>登录</summary>
        /// <param name="name"></param>
        /// <param name="password"></param>
        /// <param name="rememberme">是否记住密码</param>
        /// <returns></returns>
        IManageUser Login(String name, String password, Boolean rememberme = false);

        /// <summary>注销</summary>
        void Logout();

        /// <summary>注册用户</summary>
        /// <param name="name">用户名</param>
        /// <param name="password">密码</param>
        /// <param name="roleid">角色</param>
        /// <param name="enable">是否启用</param>
        /// <returns></returns>
        IManageUser Register(String name, String password, Int32 roleid = 0, Boolean enable = false);

        /// <summary>获取服务</summary>
        /// <remarks>
        /// 其实IServiceProvider有该扩展方法，但是在FX2里面不方面使用，所以这里保留
        /// </remarks>
        /// <typeparam name="TService"></typeparam>
        /// <returns></returns>
        TService GetService<TService>();
    }

    /// <summary>管理提供者</summary>
#if !__CORE__
    public abstract class ManageProvider : IManageProvider, IErrorInfoProvider
#else
    public abstract class ManageProvider : IManageProvider
#endif
    {
        #region 静态实例
        static ManageProvider()
        {
            var ioc = ObjectContainer.Current;
            // 外部管理提供者需要手工覆盖
            ioc.Register<IManageProvider, DefaultManageProvider>();

            ioc.AutoRegister<IRole, Role>()
                .AutoRegister<IMenu, Menu>()
                .AutoRegister<ILog, Log>()
                .AutoRegister<IUser, UserX>();
        }

        /// <summary>当前管理提供者</summary>
        public static IManageProvider Provider => ObjectContainer.Current.ResolveInstance<IManageProvider>();

        /// <summary>当前登录用户</summary>
        public static IUser User { get => Provider.Current as IUser; set => Provider.Current = value as IManageUser; }

        /// <summary>菜单工厂</summary>
        public static IMenuFactory Menu => GetFactory<IMenu>() as IMenuFactory;
        #endregion

        #region 属性
        /// <summary>保存于Cookie的凭证</summary>
        public String CookieKey { get; set; } = "Admin";

        /// <summary>保存于Session的凭证</summary>
        public String SessionKey { get; set; } = "Admin";
        #endregion

        #region IManageProvider 接口
        /// <summary>当前用户</summary>
        public virtual IManageUser Current { get => GetCurrent(); set => SetCurrent(value); }

        /// <summary>获取当前用户</summary>
        /// <param name="context"></param>
        /// <returns></returns>
        public virtual IManageUser GetCurrent(IServiceProvider context = null)
        {
#if !__CORE__
            if (context == null) context = HttpContext.Current;
            var ss = context.GetService<HttpSessionState>();
            if (ss == null) return null;

            // 从Session中获取
            return ss[SessionKey] as IManageUser;
#else
            return null;
#endif
        }

        /// <summary>设置当前用户</summary>
        /// <param name="user"></param>
        /// <param name="context"></param>
        public virtual void SetCurrent(IManageUser user, IServiceProvider context = null)
        {
#if !__CORE__
            if (context == null) context = HttpContext.Current;
            var ss = context.GetService<HttpSessionState>();
            if (ss == null) return;

            var key = SessionKey;
            // 特殊处理注销
            if (user == null)
            {
                // 修改Session
                ss.Remove(key);

                if (ss[key] is IAuthUser au)
                {
                    au.Online = false;
                    au.Save();
                }
            }
            else
            {
                // 修改Session
                ss[key] = user;
            }
#else
#endif
        }

        /// <summary>根据用户编号查找</summary>
        /// <param name="userid"></param>
        /// <returns></returns>
        public abstract IManageUser FindByID(Object userid);

        /// <summary>根据用户帐号查找</summary>
        /// <param name="name"></param>
        /// <returns></returns>
        public abstract IManageUser FindByName(String name);

        /// <summary>登录</summary>
        /// <param name="name"></param>
        /// <param name="password"></param>
        /// <param name="rememberme">是否记住密码</param>
        /// <returns></returns>
        public abstract IManageUser Login(String name, String password, Boolean rememberme);

        /// <summary>注销</summary>
        public virtual void Logout()
        {
            Current = null;

#if !__CORE__
            // 注销时销毁所有Session
            var context = HttpContext.Current;
            var ss = context?.Session;
            ss?.Clear();
#endif

            // 销毁Cookie
            this.SaveCookie(null, TimeSpan.FromDays(-1));
        }

        /// <summary>注册用户</summary>
        /// <param name="name">用户名</param>
        /// <param name="password">密码</param>
        /// <param name="roleid">角色</param>
        /// <param name="enable">是否启用。某些系统可能需要验证审核</param>
        /// <returns></returns>
        public abstract IManageUser Register(String name, String password, Int32 roleid, Boolean enable);

        /// <summary>获取服务</summary>
        /// <typeparam name="TService"></typeparam>
        /// <returns></returns>
        public TService GetService<TService>() => (TService)GetService(typeof(TService));

        /// <summary>获取服务</summary>
        /// <param name="serviceType"></param>
        /// <returns></returns>
        public virtual Object GetService(Type serviceType)
        {
            var container = XCodeService.Container;
            return container.Resolve(serviceType);
        }
        #endregion

#if !__CORE__
        #region IErrorInfoProvider 成员
        void IErrorInfoProvider.AddInfo(Exception ex, StringBuilder builder)
        {
            var user = Current;
            if (user != null)
            {
                var e = user as IEntity;
                if (e["RoleName"] != null)
                    builder.AppendFormat("登录：{0}({1})\r\n", user.Name, e["RoleName"]);
                else
                    builder.AppendFormat("登录：{0}\r\n", user.Name);
            }
        }
        #endregion
#endif

        #region 实体类扩展
        /// <summary>根据实体类接口获取实体工厂</summary>
        /// <typeparam name="TIEntity"></typeparam>
        /// <returns></returns>
        internal static IEntityOperate GetFactory<TIEntity>()
        {
            var container = XCodeService.Container;
            var type = container.ResolveType<TIEntity>();
            if (type == null) return null;

            return EntityFactory.CreateOperate(type);
        }

        internal static T Get<T>()
        {
            var eop = GetFactory<T>();
            if (eop == null) return default(T);

            return (T)eop.Default;
        }
        #endregion
    }

    /// <summary>基于User实体类的管理提供者</summary>
    /// <typeparam name="TUser"></typeparam>
    public class ManageProvider<TUser> : ManageProvider where TUser : User<TUser>, new()
    {
        /// <summary>根据用户编号查找</summary>
        /// <param name="userid"></param>
        /// <returns></returns>
        public override IManageUser FindByID(Object userid) => User<TUser>.FindByID((userid + "").ToInt(-1));

        /// <summary>根据用户帐号查找</summary>
        /// <param name="name"></param>
        /// <returns></returns>
        public override IManageUser FindByName(String name) => User<TUser>.FindByName(name);

        /// <summary>登录</summary>
        /// <param name="name"></param>
        /// <param name="password"></param>
        /// <param name="rememberme">是否记住密码</param>
        /// <returns></returns>
        public override IManageUser Login(String name, String password, Boolean rememberme)
        {
            var user = User<TUser>.Login(name, password, rememberme);

            Current = user;

            var expire = TimeSpan.FromDays(0);
            if (rememberme && user != null) expire = TimeSpan.FromDays(365);
            this.SaveCookie(user, expire);

#if !__CORE__
            //if (rememberme && user != null) this.SetCookie(TimeSpan.FromDays(365));
            //{
            //    var cookie = HttpContext.Current.Response.Cookies[CookieKey];
            //    if (cookie != null) cookie.Expires = DateTime.Now.Date.AddYears(1);
            //}
#endif

            return user;
        }

        ///// <summary>注销</summary>
        //public override void Logout()
        //{
        //    base.Logout();

        //    this.SaveCookie(null);
        //}

        /// <summary>注册用户</summary>
        /// <param name="name">用户名</param>
        /// <param name="password">密码</param>
        /// <param name="roleid">角色</param>
        /// <param name="enable">是否启用。某些系统可能需要验证审核</param>
        /// <returns></returns>
        public override IManageUser Register(String name, String password, Int32 roleid, Boolean enable)
        {
            var user = new TUser
            {
                Name = name,
                Password = password,
                Enable = enable,
                RoleID = roleid
            };

            user.Register();

            return user;
        }
    }

    class DefaultManageProvider : ManageProvider<UserX> { }

    /// <summary>管理提供者助手</summary>
    public static class ManagerProviderHelper
    {
        /// <summary>设置当前用户</summary>
        /// <param name="provider">提供者</param>
        /// <param name="context">Http上下文，兼容NetCore</param>
        public static void SetPrincipal(this IManageProvider provider, IServiceProvider context = null)
        {
#if !__CORE__
            //var ctx = context as Microsoft.AspNetCore.Http.HttpContext;
            var ctx = context as HttpContext ?? HttpContext.Current;
            if (ctx == null) return;

            var user = provider.GetCurrent(context);
            if (user == null) return;

            if (!(user is IIdentity id) || ctx.User?.Identity == id) return;

            // 角色列表
            var roles = new List<String>();
            if (user is IUser user2) roles.AddRange(user2.Roles.Select(e => e + ""));

            var up = new GenericPrincipal(id, roles.ToArray());
            ctx.User = up;
            Thread.CurrentPrincipal = up;
#endif
        }

        /// <summary>尝试登录。如果Session未登录则借助Cookie</summary>
        /// <param name="provider">提供者</param>
        /// <param name="context">Http上下文，兼容NetCore</param>
        public static IManageUser TryLogin(this IManageProvider provider, IServiceProvider context = null)
        {
            // 判断当前登录用户
            var user = provider.GetCurrent(context);
            if (user == null)
            {
                // 尝试从Cookie登录
                user = provider.LoadCookie(true, context);
                if (user != null) provider.SetCurrent(user, context);
            }

            // 设置前端当前用户
            if (user != null) provider.SetPrincipal(context);

            return user;
        }

        #region Cookie
        private static String GetCookieKey(IManageProvider provider)
        {
            var key = (provider as ManageProvider)?.CookieKey;
            if (key.IsNullOrEmpty()) key = "cube_user";

            return key;
        }

        /// <summary>从Cookie加载用户信息</summary>
        /// <param name="provider">提供者</param>
        /// <param name="autologin">是否自动登录</param>
        /// <param name="context">Http上下文，兼容NetCore</param>
        /// <returns></returns>
        public static IManageUser LoadCookie(this IManageProvider provider, Boolean autologin = true, IServiceProvider context = null)
        {
#if !__CORE__
            var key = GetCookieKey(provider);

            if (context == null) context = HttpContext.Current;
            var req = context.GetService<HttpRequest>();
            var cookie = req?.Cookies[key];
            if (cookie == null) return null;

            var m = new CookieModel();
            if (!m.Read(cookie, SysConfig.Current.InstallTime.ToFullString())) return null;

            var user = HttpUtility.UrlDecode(m.UserName);
            //var user = HttpUtility.UrlDecode(cookie["u"]);
            //var pass = cookie["p"];
            //var exp = cookie["e"].ToInt(-1);
            if (user.IsNullOrEmpty() || m.Password.IsNullOrEmpty()) return null;

            // 判断有效期
            //var expire = exp.ToDateTime();
            if (m.Expire < DateTime.Now) return null;

            var u = provider.FindByName(user);
            if (u == null || !u.Enable) return null;

            var mu = u as IAuthUser;
            if (!m.Password.EqualIgnoreCase(mu.Password.MD5())) return null;

            // 保存登录信息
            if (autologin)
            {
                mu.SaveLogin(null);
                LogProvider.Provider.WriteLog("用户", "自动登录", $"{user} Time={m.Time} Expire={m.Expire}", u.ID, u + "");
            }

            return u;
#else
            return null;
#endif
        }

        /// <summary>保存用户信息到Cookie</summary>
        /// <param name="provider">提供者</param>
        /// <param name="user">用户</param>
        /// <param name="expire">过期时间</param>
        /// <param name="context">Http上下文，兼容NetCore</param>
        public static void SaveCookie(this IManageProvider provider, IManageUser user, TimeSpan expire, IServiceProvider context = null)
        {
#if !__CORE__
            if (context == null) context = HttpContext.Current;

            var req = context?.GetService<HttpRequest>();
            var res = context?.GetService<HttpResponse>();
            if (req == null || res == null) return;

            var key = GetCookieKey(provider);
            var reqcookie = req.Cookies[key];
            if (user is IAuthUser au)
            {
                var u = HttpUtility.UrlEncode(user.Name);
                var p = !au.Password.IsNullOrEmpty() ? au.Password.MD5() : null;

                var m = new CookieModel
                {
                    UserName = u,
                    Password = p,
                    Time = DateTime.Now,
                    Expire = DateTime.Now.Add(expire)
                };
                m.Write(res.Cookies[key], SysConfig.Current.InstallTime.ToFullString());
            }
            else
            {
                var cookie = res.Cookies[key];
                cookie.Value = null;
                cookie.Expires = DateTime.Now.AddYears(-1);
            }
#endif
        }

#if !__CORE__
        class CookieModel
        {
        #region 属性
            public String UserName { get; set; }
            public String Password { get; set; }
            public DateTime Time { get; set; }
            public DateTime Expire { get; set; }
            public String Sign { get; set; }
        #endregion

        #region 方法
            public Boolean Read(HttpCookie cookie, String key)
            {
                UserName = cookie["u"];
                Password = cookie["p"];
                Time = (cookie["t"] + "").ToInt().ToDateTime();
                Expire = (cookie["e"] + "").ToInt().ToDateTime();
                Sign = cookie["s"];

                var str = $"u={UserName}&p={Password}&t={Time.ToInt()}&e={Expire.ToInt()}&k={key}";

                return str.MD5() == Sign;
            }

            public void Write(HttpCookie cookie, String key)
            {
                cookie.HttpOnly = true;
                cookie["u"] = UserName;
                cookie["p"] = Password;

                var dt = Time;
                cookie["t"] = dt.ToInt() + "";

                var exp = Expire;
                cookie.Expires = exp;
                cookie["e"] = exp.ToInt() + "";

                var str = $"u={UserName}&p={Password}&t={Time.ToInt()}&e={Expire.ToInt()}&k={key}";
                Sign = str.MD5();

                cookie["s"] = Sign;
            }
        #endregion
        }
#endif
        #endregion
    }
}