using ERP.Framework.Cache;
using ERP.Framework.Config;
using ERP.Framework.Constants;
using ERP.Framework.Exceptions;
using ERP.Framework.Resource;
using ERP.Framework.Security;
using ERP.Framework.Utils;
using ERP.Framework.WebApi;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Configuration;
using Newtonsoft.Json;
using System.IdentityModel.Tokens.Jwt;
using System.Net;
using System.Security.Claims;

namespace ERP.Framework.Middleware
{
    /// <summary>
    /// 验证 (解签 header附带用户id) useJwt
    /// </summary>
    public class AuthenticationMiddleware : IMiddleware
    {
        private readonly IConfiguration _configuration;

        public AuthenticationMiddleware(IConfiguration configuration)
        {
            this._configuration = configuration;
        }

        public async Task InvokeAsync(HttpContext context, RequestDelegate next)
        {
            var path = context.Request.Path.ToString();
            var securityConfig = _configuration.GetSection(FrameworkConstant.SECURITY_CONFIG).Get<SecurityConfig>() ?? new SecurityConfig();

            if (securityConfig.WhiteList != null && UrlUtil.Match(path, securityConfig.WhiteList))
            {
                await next(context);
                return;
            }

            var token = context.Request.Headers[AuthConstant.HEADER].ToString().Replace(FrameworkConstant.TOKEN_PREFIX, "").TrimStart();

            var isValid = TokenHelper.ValidateToken(token, securityConfig.JwtSecurityKey);

            if (!isValid)
            {
                // 返回401状态码和自定义错误信息
                context.Response.StatusCode = (int)HttpStatusCode.Unauthorized;
                context.Response.ContentType = "application/json";

                var errorJson = JsonConvert.SerializeObject(new Result()
                {
                    Code = ErrorCode.TOKEN_VALIDATE,
                    Message = FrameworkI18N.TokenValidate!
                });

                await context.Response.WriteAsync(errorJson);

                return;
            }

            var claims = TokenHelper.GetClaims(token);
            var tokenId = claims.FirstOrDefault(t => t.Type == JwtRegisteredClaimNames.UniqueName)!.Value;
            var userId = claims.FirstOrDefault(t => t.Type == JwtRegisteredClaimNames.NameId)!.Value;
            var userName = claims.FirstOrDefault(t => t.Type == ClaimTypes.Name)!.Value;

            var checkLastActivityResult = CheckLastActivity(tokenId, securityConfig.ActivityTimeOut);

            if (checkLastActivityResult != null)
            {
                context.Response.StatusCode = (int)HttpStatusCode.Unauthorized;
                context.Response.ContentType = "application/json";
                await context.Response.WriteAsync(JsonConvert.SerializeObject(checkLastActivityResult));
                return;
            }

            context.Items["TokenId"] = tokenId;
            context.Items["UserId"] = userId;
            context.Items["UserName"] = userName;

            await next(context);
            return;
        }

        private static Result? CheckLastActivity(string tokenId, int activityTimeOut)
        {
            DateTime date;
            var result = new Result();
            var key = AuthConstant.LAST_ACTIVITY + tokenId;
            var lastActivity = RedisHelper.GetWithExpire(key);

            var value = lastActivity.Value.ToString();
            var expireTime = lastActivity.Expiry;

            if (value.IsNullOrEmpty())
            {
                result.Code = ErrorCode.IDLE_TIME_OUT;
                result.Message = FrameworkI18N.IdleTimeOut!;
                return result;
            }

            if (value == "-1")
            {
                result.Code = ErrorCode.KICKED_OUT;
                result.Message = FrameworkI18N.KickedOut!;
                return result;
            }

            if (value == "-2")
            {
                result.Code = ErrorCode.CONCURRENT_LOGIN;
                result.Message = FrameworkI18N.ConcurrentLogin!;
                return result;
            }

            if (DateTime.TryParse(value, out date))
            {
                var isOnline = DateTime.Now <= date;

                if (isOnline)
                {
                    SetLastActivityCache(tokenId, activityTimeOut, expireTime);
                }
                else
                {
                    result.Code = ErrorCode.IDLE_TIME_OUT;
                    result.Message = FrameworkI18N.IdleTimeOut!;
                    return result;
                }
            }

            return null;
        }

        /// <summary>
        /// 刷新last Activity
        /// </summary>
        /// <param name="tokenId"></param>
        /// <param name="activityTimeOut"></param>
        private static void SetLastActivityCache(
            string tokenId
            , int activityTimeOut
            , TimeSpan? expireTime)
        {
            var key = AuthConstant.LAST_ACTIVITY + tokenId;
            var val = DateTime.Now.AddMinutes(activityTimeOut).ToDateLongString();
            RedisHelper.SaveExpire(key, val, expireTime);
        }
    }

    public static class AuthenticationMiddlewareExtensions
    {
        public static IApplicationBuilder UseAuthenticationMiddleware(this IApplicationBuilder builder)
        {
            return builder.UseMiddleware<AuthenticationMiddleware>();
        }
    }
}