using Microsoft.AspNetCore.Http;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Text.Json;
using System.Threading.Tasks;
using Common;
using Common.Tools;

namespace djy_IsfApi
{
    /*
     使用方法 在startup  Configure中添加
       app.UseMiddleware<MytMiddleware>();
         */
    /// <summary>
    /// 访问管道
    /// </summary>
    public class MytMiddleware
    {
        /// <summary>
        /// 
        /// </summary>
        private readonly RequestDelegate next;
        public MytMiddleware(RequestDelegate next)
        {
            this.next = next;
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="context"></param>
        /// <returns></returns>
        public async Task Invoke(HttpContext context)
        {
            try
            {
                await next(context);
            }
            catch (Exception ex)
            {
                await HandleExceptionAsync(context, ex);
            }
            finally
            {
                var statuscode = context.Response.StatusCode;
                var h = context.Response.HasStarted;
                ReturnResult<string> rr = new ReturnResult<string>();

                if (statuscode == 401|| statuscode == 400)
                {
                    //页面的状态码 根据需求调整是否修改
                    switch (statuscode)
                    {
                        case 400:
                            rr.Message = "请求错误！";
                            rr.Code = 400;
                            break;
                        case 401:
                            rr.Message = "授权验证失败或已过期,请重新登录";
                            rr.Code = 401;
                            break;
                    }
                  
                    rr.Status = false;
                   
                    var response = context.Response;
                   

                    try
                    { response.StatusCode = 200; }
                    catch (Exception ex) {
                        var msg = ex.Message;
                    }
                    response.ContentType = "application/json";
                    await response.WriteAsync(JsonSerializer.Serialize(rr, new JsonSerializerOptions(JsonSerializerDefaults.Web))).ConfigureAwait(false);

                }
                


            }
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="context"></param>
        /// <param name="exception"></param>
        /// <returns></returns>
        private static async Task HandleExceptionAsync(HttpContext context, Exception exception)
        {
            if (exception == null) return;
            await WriteExceptionAsync(context, exception).ConfigureAwait(false);
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="context"></param>
        /// <param name="exception"></param>
        /// <returns></returns>
        private static async Task WriteExceptionAsync(HttpContext context, Exception exception)
        {
            //记录日志

            //返回友好的提示
            var response = context.Response;

            //状态码
            if (exception is UnauthorizedAccessException)
                response.StatusCode = (int)HttpStatusCode.Unauthorized;
            else if (exception is Exception)
                response.StatusCode = (int)HttpStatusCode.BadRequest;

            response.ContentType = context.Request.Headers["Accept"];
            response.StatusCode = 200;
            
            string msg = string.Format("内部错误:{0}", exception.GetBaseException().Message);

            try
            {
                var json = JsonSerializer.Serialize(exception.GetBaseException());
                Tools.ServerWarnMessageErr(msg + "   " + json);
            }
            catch { }

            ReturnResult<string> rr = new ReturnResult<string>();
            rr.Code = 400;
            rr.Status = false;
            rr.Message = msg;
            rr.Data = rr.Message;
            response.ContentType = "application/json";
            await response.WriteAsync(JsonSerializer.Serialize(rr, new JsonSerializerOptions(JsonSerializerDefaults.Web))).ConfigureAwait(false);
        }



    }
}