package com.happy.common.util;


import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
// vo实体类参数

import com.happy.Model.weixin.CodeEntityVo;
import com.happy.Model.weixin.WeiXinUtil;
import org.bouncycastle.util.encoders.Base64;
import lombok.extern.slf4j.Slf4j;
import org.apache.http.util.TextUtils;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.springframework.stereotype.Component;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.security.AlgorithmParameters;
import java.security.Security;
import java.util.*;

public class WechatUtil {

    /**
     * 获取小程序code换取openid、session_key
     *
     * @param code
     * @return
     */
    public static JSONObject getOpenId(String code) {

        String url = "https://api.weixin.qq.com/sns/jscode2session?appid=" + WeiXinUtil.appid_c
                + "&secret=" + WeiXinUtil.screct_c + "&js_code=" + code + "&grant_type=authorization_code";
        PrintWriter out = null;
        BufferedReader in = null;
        String line;
        StringBuffer stringBuffer = new StringBuffer();
        try {
            URL realUrl = new URL(url);
            // 打开和URL之间的连接
            URLConnection conn = realUrl.openConnection();

            // 设置通用的请求属性 设置请求格式
            //设置返回类型
            conn.setRequestProperty("contentType", "text/plain");
            //设置请求类型
            conn.setRequestProperty("content-type", "application/x-www-form-urlencoded");
            //设置超时时间
            conn.setConnectTimeout(1000);
            conn.setReadTimeout(1000);
            conn.setDoOutput(true);
            conn.connect();
            // 获取URLConnection对象对应的输出流
            out = new PrintWriter(conn.getOutputStream());
            // flush输出流的缓冲
            out.flush();
            // 定义BufferedReader输入流来读取URL的响应    设置接收格式
            in = new BufferedReader(
                    new InputStreamReader(conn.getInputStream(), "UTF-8"));
            while ((line = in.readLine()) != null) {
                stringBuffer.append(line);
            }
            JSONObject jsonObject = JSONObject.parseObject(stringBuffer.toString());
            return jsonObject;

        } catch (Exception e) {
            e.printStackTrace();
        }
        //使用finally块来关闭输出流、输入流
        finally {
            try {
                if (out != null) {
                    out.close();
                }
                if (in != null) {
                    in.close();
                }
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
        return null;
    }

    /**
     *   在上面的代码中我们已经获取到了openid和session_key了，而code信息中是不能获取到用户的手机号码的，
     *   解析微信手机号的相关数据需要openid和session_key才行，所以在上面代码中，我将相关数据返回给了前端，
     *   前端将我传回的参数，还有第二次请求中的iv、encryptedData一起传回给后端，然后我们进行解密
     * **/
    public static Map<String, Object> getPhoneNumber(CodeEntityVo vo,String openid,String session_key) {
        Map<String,Object> map=new HashMap<>();
        if (openid!=null) {
            if(session_key==null){
                return null;
            }
            map.put("openid",openid);
            // 被加密的数据
            byte[] dataByte = Base64.decode(vo.getEncryptedData());
            // 加密秘钥
            byte[] keyByte = Base64.decode(session_key);
            // 偏移量
            byte[] ivByte = Base64.decode(vo.getIv());
            try {
                // 如果密钥不足16位，那么就补足. 这个if 中的内容很重要
                int base = 16;
                String result = null;
                if (keyByte.length % base != 0) {
                    int groups = keyByte.length / base + (keyByte.length % base != 0 ? 1 : 0);
                    byte[] temp = new byte[groups * base];
                    Arrays.fill(temp, (byte) 0);
                    System.arraycopy(keyByte, 0, temp, 0, keyByte.length);
                    keyByte = temp;
                }
                // 初始化
                Security.addProvider(new BouncyCastleProvider());
                Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding", "BC");
                SecretKeySpec spec = new SecretKeySpec(keyByte, "AES");
                AlgorithmParameters parameters = AlgorithmParameters.getInstance("AES");
                parameters.init(new IvParameterSpec(ivByte));
                // 初始化
                cipher.init(Cipher.DECRYPT_MODE, spec, parameters);
                byte[] resultByte = cipher.doFinal(dataByte);
                if (null != resultByte && resultByte.length > 0) {
                    result = new String(resultByte, "UTF-8");
                    JSONObject jsonObject = JSONObject.parseObject(result);
                    map.put("param",jsonObject);
                    return map;
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        return null;
    }
}