using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.DependencyInjection;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http.Headers;
using System.Net;
using System.Text;
using System.Threading.Tasks;
using System.Security.Policy;
using System.Text.Json;
using Learn.Archives.Core.Model.Dto;
using Microsoft.AspNetCore.Mvc.RazorPages;

namespace Learn.Archives.Core.Common
{
    public static class UserCenterServiceExpand
    {

        /// <summary>
        /// 添加 当前作用域登录用户信息
        /// </summary>
        /// <param name="services"></param>
        public static void AddUserCenterServiceExpand(this IServiceCollection services)
        {
            services.AddScoped<UserCenterService>();
        }
    }
    /// <summary>
    /// 调用 UserCenter服务的接口
    /// </summary>
    public class UserCenterService
    {
        private readonly IHttpClientFactory _httpClientFactory;

        public UserCenterService(IHttpClientFactory httpClientFactory)
        {
            _httpClientFactory = httpClientFactory;
        }

        const string API_getpageuserlist = "back/users/getpageuserlist";
        const string API_ImportJsonData = "back/users/importjsondata";
        /// <summary>
        /// 请求用户中心 接口
        /// </summary>
        /// <param name="context"></param>
        /// <returns></returns>
        public async Task<PageResult<UserInfoResponceDto>> CallAPI_GetPageUserList(HttpContext context)
        {
            var res = await ForwardRequestAsync<BaseReturn<PageResult<UserInfoResponceDto>>>(API_getpageuserlist, context);
            if (res==null || res.Code != 200)
                Oh.Error(res.Message, res.Code);
            return res.Data;
        }
        /// <summary>
        /// 请求用户中心 接口
        /// </summary>
        /// <param name="context"></param>
        /// <returns></returns>
        public async Task<UserImportRes> CallAPI_ImportJsonData(HttpContext context,object data)
        {

            var httpClient = _httpClientFactory.CreateClient();

            var targetUri = new Uri(AppCommon.Config.UserCenterService.API +"/"+ API_ImportJsonData);
            var requestMessage = new HttpRequestMessage(new HttpMethod("POST"), targetUri);

            if (context.Request.Headers.TryGetValue("Authorization", out var authValues))
                requestMessage.Headers.Authorization = AuthenticationHeaderValue.Parse(authValues.FirstOrDefault());
            requestMessage.Content = new StringContent(data.ToJson(), Encoding.UTF8, "application/json");
            
            var responseMessage = await httpClient.SendAsync(requestMessage, HttpCompletionOption.ResponseHeadersRead);
            var resStr = string.Empty;
            try
            {
                resStr= await responseMessage?.Content?.ReadAsStringAsync();
              
            }
            catch (Exception ex)
            {
                return Oh.Error<UserImportRes>($"请求用户中心出现异常 {resStr} {ex.Message}");
            }
            if(string.IsNullOrEmpty(resStr))
                return Oh.Error<UserImportRes>($"请求用户中心出现异常 返回了空数据");
            var res = JsonSerializer.Deserialize<BaseReturn<UserImportRes>>(resStr);
            if (res == null || res.Code != 200)
                Oh.Error(res.Message, res.Code);
            return res.Data;
        }
        /// <summary>
        /// 转发请求
        /// </summary>
        /// <param name="url">用户中心API</param>
        /// <param name="context">上下文</param>
        /// <returns></returns>
        public async Task<T> ForwardRequestAsync<T>(string url, HttpContext context) where T : class, new()
        {
            var httpClient = _httpClientFactory.CreateClient();
            var Request = context.Request;
            try
            {
                // ========== 1. 准备目标请求 ==========
                var targetUri = new Uri(AppCommon.Config.UserCenterService.API+"/"+ url);

                // 创建 HttpRequestMessage，使用与当前请求相同的 HttpMethod
                var requestMessage = new HttpRequestMessage(new HttpMethod(Request.Method), targetUri);

                // ========== 2. 复制请求头 ==========
                // ========== 3. 处理请求体（Body）==========
                if (Request.Body != null && (Request.Method == "POST" || Request.Method == "PUT" || Request.Method == "PATCH"))
                {
                    // 由于 Request.Body 只能读取一次，我们需要缓存它（ASP.NET Core 默认不缓存）
                    // 如果你希望多次读取 Body，可以使用 EnableBuffering() 中间件，或者在这里直接读取并重新赋值
                    Request.EnableBuffering(); // 允许重新读取请求流
                    Request.Body.Position = 0; // 重置 Stream 位置，以便后续中间件或框架再次读取（如有必要）
                    using var reader = new System.IO.StreamReader(Request.Body);
                    var body = await reader.ReadToEndAsync();
                    if (!string.IsNullOrEmpty(body))
                        requestMessage.Content = new StringContent(body, Encoding.UTF8, Request.ContentType);
                }
                // ========== 4. 添加 Authorization 等自定义 Header（可选）==========
                if (Request.Headers.TryGetValue("Authorization", out var authValues))
                    requestMessage.Headers.Authorization = AuthenticationHeaderValue.Parse(authValues.FirstOrDefault());
                // ========== 5. 发送请求到目标服务器 ==========
                var responseMessage = await httpClient.SendAsync(requestMessage, HttpCompletionOption.ResponseHeadersRead);
                var resStr = await responseMessage.Content?.ReadAsStringAsync();
                return JsonSerializer.Deserialize<T>(resStr);
            }
            catch
            {
                throw;
            }
        }

    }
}