using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Security.Cryptography;
using System.Text;
using System.Web;
using System.Xml;

/// <summary>
/// WX_Util 的摘要说明
/// </summary>
public class WX_Util
{
    public static string getRandomStr()
    {
        return Guid.NewGuid().ToString().Replace("-", "");
    }
    public static string extract(string str, string key)
    {
        SortedDictionary<string, string> map = new SortedDictionary<string, string>();
        XmlDocument xmlDoc = new XmlDocument();
        xmlDoc.LoadXml(str);
        XmlNode xmlNode = xmlDoc.FirstChild;//获取到根节点<xml>
        XmlNodeList nodes = xmlNode.ChildNodes;
        foreach (XmlNode xn in nodes)
        {
            XmlElement xe = (XmlElement)xn;
            if (key.Equals(xe.Name))
            {
                return xe.InnerText;
            }
        }
        return "";
    }

    public static ReturnBean submit(SortedDictionary<string, string> map, string key)
    {
        string str = null;
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create("https://api.mch.weixin.qq.com/pay/unifiedorder");
        request.Method = "POST";
        Stream requestStream = request.GetRequestStream();
        StreamWriter streamWriter = new StreamWriter(requestStream);
        streamWriter.Write(getXML(map, key));
        streamWriter.Flush();

        HttpWebResponse response = (HttpWebResponse)request.GetResponse();
        Stream responseStream = response.GetResponseStream();
        StreamReader streamReader = new StreamReader(responseStream);
        str = streamReader.ReadToEnd();

        streamWriter.Close();
        streamReader.Close();
        WX_Util.log(str);
        return new ReturnBean(str);
    }

    public static void log(string str)
    {
        System.IO.FileStream file = new System.IO.FileStream(HttpContext.Current.Server.MapPath("/upload/log.txt"), System.IO.FileMode.Append);
        System.IO.StreamWriter writer = new System.IO.StreamWriter(file);
        writer.WriteLine(str + "\n\r");
        writer.Close();
    }

    public static string getXML(SortedDictionary<string, string> map, string key)
    {
        string xml = "<xml>";
        xml += "<sign>" + sign(map, key) + "</sign>";
        foreach (KeyValuePair<string, string> pair in map)
        {
            if (pair.Value != null)
            {
                if (pair.Value.GetType() == typeof(int))
                {
                    xml += "<" + pair.Key + ">" + pair.Value + "</" + pair.Key + ">";
                }
                else if (pair.Value.GetType() == typeof(string))
                {
                    xml += "<" + pair.Key + ">" + "<![CDATA[" + pair.Value + "]]></" + pair.Key + ">";
                }
            }
        }
        xml += "</xml>";
        return xml;
    }

    public static string sign(SortedDictionary<string, string> map, string key)
    {
        string strb = "";
        foreach (KeyValuePair<string, string> pair in map)
        {
            if (pair.Key != "sign" && pair.Value != "")
            {
                strb += pair.Key + "=" + pair.Value + "&";
            }
        }
        strb += "key=" + key;

        return md5(strb);
    }

    public static string md5(string str)
    {
        var md5 = MD5.Create();
        var bs = md5.ComputeHash(Encoding.UTF8.GetBytes(str));
        var sb = new StringBuilder();
        foreach (byte b in bs)
        {
            sb.Append(b.ToString("x2"));
        }
        //所有字符转为大写
        return sb.ToString().ToUpper();
    }
    public static string getRequestStr(HttpRequest request)
    {
        System.IO.Stream s = request.InputStream;
        int count = 0;
        byte[] buffer = new byte[1024];
        StringBuilder builder = new StringBuilder();
        while ((count = s.Read(buffer, 0, 1024)) > 0)
        {
            builder.Append(Encoding.UTF8.GetString(buffer, 0, count));
        }
        s.Flush();
        s.Close();
        s.Dispose();

        return builder.ToString();
    }
    public WX_Util()
    {
        //
        // TODO: 在此处添加构造函数逻辑
        //
    }
}