using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Web.Script.Serialization;

namespace SiteCore
{
    public class JSAPI
    {
        public static string appid = "wxec9d729c4e1b1af3";
        public static string appsec = "11870bcbff21b21f27be06b99e3aa7c8";
        static string tokenUrl = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid={0}&secret={1}";
        static string jsapiUrl = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?access_token={0}&type=jsapi";
        static object jsObj = new Object();
        private static object getAt(HttpHelper http)
        {
            object cat = WebCache.GetRunCache("jsAt");
            if (cat == null)
            {
                lock (jsObj)
                {
                    //http = new HttpHelper();
                    HttpItem item = new HttpItem()
                    {
                        URL = string.Format(tokenUrl, appid, appsec)
                    };
                    HttpResult hResult = http.GetHtml(item);
                    string html = hResult.Html;
                    JavaScriptSerializer jss = new JavaScriptSerializer();
                    Dictionary<string, object> jObj = jss.Deserialize<Dictionary<string, object>>(html);
                    if (!jObj.ContainsKey("errcode"))
                    {
                        string at = jObj["access_token"].ToString();
                        WebCache.AddRunCacheTime("jsAt", at, 100);
                        cat = at;
                    }
                }
            }
            return cat;
        }

        /// <summary>
        /// 获取jsapi_ticket
        /// jsapi_ticket是公众号用于调用微信JS接口的临时票据。
        /// 正常情况下，jsapi_ticket的有效期为7200秒，通过access_token来获取。
        /// 由于获取jsapi_ticket的api调用次数非常有限，频繁刷新jsapi_ticket会导致api调用受限，影响自身业务，开发者必须在自己的服务全局缓存jsapi_ticket 。
        /// </summary>
        /// <param name="access_token">BasicAPI获取的access_token,也可以通过TokenHelper获取</param>
        /// <returns></returns>
        public static dynamic GetTickect()
        {

            HttpHelper http = new HttpHelper();
            object acc = getAt(http);
            if (acc == null)
            {
                return "";
            }
            string access_token = getAt(http).ToString();
            HttpItem item = new HttpItem()
            {
                URL = string.Format(jsapiUrl, access_token)
            };
            HttpResult hResult = http.GetHtml(item);
            string html = hResult.Html;

            string jsapi_ticket = "";
            JavaScriptSerializer serializer = new JavaScriptSerializer();
            Dictionary<string, object> json = (Dictionary<string, object>)serializer.DeserializeObject(html);
            object value;
            if (json.TryGetValue("ticket", out value))
            {
                jsapi_ticket = value.ToString();
            }
            return jsapi_ticket;
        }

        #region 获取时间戳
        public static string GetTimeStamp()
        {
            TimeSpan ts = DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0, 0);
            return Convert.ToInt64(ts.TotalSeconds).ToString();
        }
        #endregion

        #region 生成随机字符串nonceStr
        ///<summary>
        ///生成随机字符串
        ///</summary>
        ///<param name="length">目标字符串的长度</param>
        ///<param name="useNum">是否包含数字，1=包含，默认为包含</param>
        ///<param name="useLow">是否包含小写字母，1=包含，默认为包含</param>
        ///<param name="useUpp">是否包含大写字母，1=包含，默认为包含</param>
        ///<param name="useSpe">是否包含特殊字符，1=包含，默认为不包含</param>
        ///<param name="custom">要包含的自定义字符，直接输入要包含的字符列表</param>
        ///<returns>指定长度的随机字符串</returns>
        public static string GetRnd(int length, bool useNum, bool useLow, bool useUpp, bool useSpe, string custom)
        {
            byte[] b = new byte[4];
            new System.Security.Cryptography.RNGCryptoServiceProvider().GetBytes(b);
            Random r = new Random(BitConverter.ToInt32(b, 0));
            string s = null, str = custom;
            if (useNum == true) { str += "0123456789"; }
            if (useLow == true) { str += "abcdefghijklmnopqrstuvwxyz"; }
            if (useUpp == true) { str += "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; }
            if (useSpe == true) { str += "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~"; }
            for (int i = 0; i < length; i++)
            {
                s += str.Substring(r.Next(0, str.Length - 1), 1);
            }
            return s;
        }
        #endregion

        #region SHA1加密
        private static string GetPwd(string str)
        {
            byte[] cleanBytes = Encoding.Default.GetBytes(str);
            byte[] hashedBytes = System.Security.Cryptography.SHA1.Create().ComputeHash(cleanBytes);
            return BitConverter.ToString(hashedBytes).Replace("-", "");
        }
        #endregion


        /// <summary>
        /// 签名算法
        /// </summary>
        /// <param name="jsapi_ticket">jsapi_ticket</param>
        /// <param name="noncestr">随机字符串(必须与wx.config中的nonceStr相同)</param>
        /// <param name="timestamp">时间戳(必须与wx.config中的timestamp相同)</param>
        /// <param name="url">当前网页的URL，不包含#及其后面部分(必须是调用JS接口页面的完整URL)</param>
        /// <returns></returns>
        public static string GetSignature(string jsapi_ticket, string noncestr, long timestamp, string url, out string string1)
        {
            var string1Builder = new StringBuilder();
            string1Builder.Append("jsapi_ticket=").Append(jsapi_ticket).Append("&")
                          .Append("noncestr=").Append(noncestr).Append("&")
                          .Append("timestamp=").Append(timestamp).Append("&")
                          .Append("url=").Append(url.IndexOf("#") >= 0 ? url.Substring(0, url.IndexOf("#")) : url);
            string1 = string1Builder.ToString();
            return GetPwd(string1);
        }

        //public static string GetSignature()
        //{
        //    int nonceStrLength = 16;
        //    string timestamp = GetTimeStamp();
        //    string nonceStr = GetRnd(nonceStrLength, true, true, true, false, "");
        //    string url = Request.Url.AbsoluteUri.ToString() + "?params=value";
        //    string jsapi_ticket = GetTickect();
        //    //拼接字符串
        //    string string1 = "jsapi_ticket=" + jsapi_ticket + "&noncestr=" + nonceStr + "&timestamp=" + timestamp + "&url=" + url;
        //    //进行SHA1加密
        //    return GetPwd(string1);
        //}

    }
}