using System;
using System.Collections.Generic;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Net;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using ThoughtWorks.QRCode.Codec;

public partial class SystemManage_openid : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!Page.IsPostBack)
        {
            string code = Request.QueryString["code"];
            string state = Request.QueryString["state"];
            if (!string.IsNullOrEmpty(code) && !string.IsNullOrEmpty(state))
            {
                string openid = GetOAuthOpenId(code);
                if (openid == "")
                {
                    Response.Write("<h1>获取openid失败</h1>");
                    Response.End();
                }
                ZWL.BLL.ERPUser bll = new ZWL.BLL.ERPUser();
                bool result = bll.Setopenid(state, openid);
                if (result)
                {
                    Response.Write("<h1>绑定成功</h1>");
                    Response.End();
                }
                else
                {
                    Response.Write("<h1>绑定失败</h1>");
                    Response.End();
                }
            }
            else
            {
                string id = Request.QueryString["ID"];
                if (string.IsNullOrEmpty(id))
                    id = ZWL.Common.PublicMethod.GetSessionValue("UserID");
                if(id== "NoLogin")
                {
                    Response.Write("请先登录");
                    Response.End();
                }
                ZWL.BLL.ERPUser bll = new ZWL.BLL.ERPUser();
                string openid = bll.Getopenid(id);
                if (!string.IsNullOrEmpty(openid))
                    lbl_pic.Text = "目前绑定：" + openid;
                //生成二维码
                //https://open.weixin.qq.com/connect/oauth2/authorize?appid=wxb79cf945835c07e3&redirect_uri=http://dc.51csharp.com/SystemManage/openid.aspx&response_type=code&scope=snsapi_base&state=1&connect_redirect=1#wechat_redirect
                string url = "https://open.weixin.qq.com/connect/oauth2/authorize?appid=wxb79cf945835c07e3&redirect_uri=http://dc.51csharp.com/SystemManage/openid.aspx&response_type=code&scope=snsapi_base&state="+id+"&connect_redirect=1#wechat_redirect";
                getImg(url);
            }
        }
    }

    private string GetOAuthOpenId(string code)
    {
        string url = "https://api.weixin.qq.com/sns/oauth2/access_token?appid=wxb79cf945835c07e3&secret=e7ff8220aaae27b4dc88862bdf0a0087&code=" + code + "&grant_type=authorization_code";
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
        HttpWebResponse response = (HttpWebResponse)request.GetResponse();
        Stream stream = response.GetResponseStream();   //获取响应的字符串流
        if (stream != null)
        {
            StreamReader sr = new StreamReader(stream); //创建一个stream读取流
            string html = sr.ReadToEnd();   //从头读到尾，放到字符串html李米
            sr.Close();
            stream.Close();
            Dictionary<string, object> jsDict = Newtonsoft.Json.JsonConvert.DeserializeObject<Dictionary<string, object>>(html);
            if (jsDict.ContainsKey("openid"))
                return jsDict["openid"].ToString();
            else
                return "";
        }
        return "";
    }

    private void getImg(string url)
    {
        QRCodeEncoder endocder = new QRCodeEncoder();
        //二维码背景颜色
        //endocder.QRCodeBackgroundColor = System.Drawing.Color.ForestGreen;
        //二维码编码方式
        endocder.QRCodeEncodeMode = QRCodeEncoder.ENCODE_MODE.BYTE;
        //每个小方格的宽度
        endocder.QRCodeScale = 5;
        //二维码版本号
        //endocder.QRCodeVersion = 5;
        //二维码版本号 改成0能解决长字符串“索引超出了数组界限”问题
        endocder.QRCodeVersion = 0;
        //纠错等级
        endocder.QRCodeErrorCorrect = QRCodeEncoder.ERROR_CORRECTION.M;
        //将json串做成二维码
        try
        {
            using (Bitmap bitmap = endocder.Encode(url, System.Text.Encoding.UTF8))
            {
                using (System.IO.MemoryStream ms = new System.IO.MemoryStream())
                {
                    bitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
                    string base64 = Convert.ToBase64String(ms.ToArray());
                    Image1.ImageUrl = "data:image/png;base64," + base64;
                }
            }
        }
        catch (Exception ex)
        {
            Response.Write("生成二维码失败");
            Response.End();
        }
    }

}