using DSWeb.Areas.Dispatch.DB;
using log4net;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Configuration;
using System.IO;
using System.Linq;
using System.Text;
using System.Web;

namespace DSWeb.Areas.Dispatch.Helper
{
    public class TokenHelper
    {
        private static readonly int TokenRefreshInMiniute = 5;

        public static bool GetMpToken(string appid, out string token, out string errorMsg)
        {
            ILog logger = LogManager.GetLogger("TokenHelper");
            DataContext dataContext = new DataContext();
            var config = dataContext.MpConfigs.FirstOrDefault(c => c.AppId == appid);
            if (config == null)
            {
                token = null;
                errorMsg = $"未找到指定的AppId配置:{appid}";
                logger.Error(errorMsg);
                return false;
            }

            if (string.IsNullOrWhiteSpace(config.Token) || !config.ExpireTime.HasValue || config.ExpireTime.Value < DateTime.Now.AddMinutes(TokenRefreshInMiniute))
            {
                int expireIn = 0;

                bool success = GetToken(appid, config.AppSecret, out token, out expireIn, out errorMsg);
                if (success)
                {
                    config.Token = token;
                    config.LastUpdate = DateTime.Now;
                    config.ExpireTime = DateTime.Now.AddSeconds(expireIn);
                    dataContext.SaveChanges();

                    return true;
                }
                else
                {
                    return false;
                }
            }
            else
            {
                token = config.Token;
                errorMsg = "";
                return true;
            }
        }

        public static string RefreshTokens()
        {
            ILog logger = LogManager.GetLogger("TokenHelper");
            try
            {
                DataContext dataContext = new DataContext();
                DateTime dtExpire = DateTime.Now.AddMinutes(TokenRefreshInMiniute);
                var list = dataContext.MpConfigs.Where(c => !c.ExpireTime.HasValue || c.ExpireTime.Value < dtExpire).ToList();
                StringBuilder sbError = new StringBuilder();
                foreach (var item in list)
                {
                    string token = string.Empty;
                    int expireIn = 0;
                    string errorMsg = string.Empty;

                    bool success = GetToken(item.AppId, item.AppSecret, out token, out expireIn, out errorMsg);
                    if (success)
                    {
                        logger.Debug($"获取公众号token发送成功：{item.AppId} {token}");
                        item.Token = token;
                        item.LastUpdate = DateTime.Now;
                        item.ExpireTime = DateTime.Now.AddSeconds(expireIn);
                    }
                    else
                    {
                        sbError.AppendLine($"获取AppId为{item.AppId}的token时出错：{errorMsg}");
                    }
                }
                dataContext.SaveChanges();

                if (sbError.Length > 0)
                {
                    logger.Error($"获取公众号token发送错误：{sbError}");
                }
                return sbError.ToString();
            }
            catch (Exception ex)
            {
                logger.Error($"获取公众号token发送错误：{ex.Message}");
                logger.Error(ex.StackTrace);
                return ex.Message;
            }
        }

        private static bool GetToken(string appid, string appsecret, out string token, out int expiresIn, out string errorMsg)
        {
            string tokenUrl = $"https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid={appid}&secret={appsecret}";
            string tokenStr = WebRequestHelper.DoGet(tokenUrl);

            if (tokenStr.IndexOf("errcode") > -1)
            {
                var obj = new { errcode = 0, errmsg = "" };
                var errorJson = JsonConvert.DeserializeAnonymousType(tokenStr, obj);
                errorMsg = errorJson.errmsg;
                token = null;
                expiresIn = 0;

                return false;
            }
            else
            {
                var obj = new { access_token = "", expires_in = 0 };
                var tokenJson = JsonConvert.DeserializeAnonymousType(tokenStr, obj);

                token = tokenJson.access_token;
                expiresIn = tokenJson.expires_in;
                errorMsg = null;

                return true;
            }

        }
    }
}