package cc.mrbird.febs.pay.util;

import cc.mrbird.febs.rabbit.producter.AgentProducer;
import org.dom4j.io.SAXReader;

import javax.servlet.http.HttpServletRequest;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import java.util.HashMap;
import org.dom4j.Document;
import org.dom4j.Element;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.io.InputStream;
import java.util.*;

/**
 * <pre>
 * 微信消息工具类：事件通知、自动回复、
 * </pre>
 *
 * @author shenshao
 */
@Service(value="wechatEventUtil")
public class WechatEventUtil {


    @Autowired
    private AgentProducer agentProducer;

    private static Logger log = LoggerFactory.getLogger(WechatEventUtil.class);

    /**
     * 公众号《事件通知》服务器校验
     *
     * @param req 请求
     * @return 校验结果
     */
    public String verification(HttpServletRequest req, String wechatToken) {
        // 接收微信服务器发送请求时传递过来的参数
        String signature = req.getParameter("signature");
        String timestamp = req.getParameter("timestamp");
        String nonce = req.getParameter("nonce");

        // 将token、timestamp、nonce三个参数进行字典序排序，并拼接为一个字符串
        String sortStr = sort(wechatToken, timestamp, nonce);

        // 字符串进行shal加密
        String mySignature = shal(sortStr);
        // 校验微信服务器传递过来的签名 和  加密后的字符串是否一致, 若一致则签名通过
        if (!"".equals(signature) && !"".equals(mySignature) && signature.equals(mySignature)) {
            log.info("-----签名校验通过-----");
            return req.getParameter("echostr");
        } else {
            log.error("-----校验签名失败-----");
            return "";
        }
    }

    /**
     * 消息事件监控：关注、取消关注等事件
     * @param req
     * @return
     */
    public String messageEvent(HttpServletRequest req) {
        String result = null;
        Map<String, String> map = xmlToMap(req);
        String fromUserName = map.get("FromUserName");
        String toUserName = map.get("ToUserName");
        String msgType = map.get("MsgType");
        String content = map.get("Content");
        String eventType = map.get("Event");
        log.info("事件处理：event:{}、msgType：{}、toUserName：{}、fromUserName：{}", eventType, msgType, toUserName, fromUserName);
        if ("event".equals(msgType)) {
            if ("subscribe".equals(eventType)) {
                result = imgTextMsg(toUserName, fromUserName, "新用户注册", "欢迎光临【药王谷铺子】，点击总下角【药王谷铺子】-【商城】。", "图片地址", "点击后跳转的路径");
                log.info("新增关注事件：toUserName{}、fromUserName{}", toUserName, fromUserName);
                StringBuffer stringBuffer = new StringBuffer();
                if(map.containsKey("EventKey")){
                    /**
                     * 扫带参数二维码
                     */
                    String eventKey = map.get("EventKey");
                    stringBuffer.append(eventKey);
                    stringBuffer.append("-");
                    stringBuffer.append(fromUserName);
                    agentProducer.sendMemberSubScanMsg(stringBuffer.toString());
                }
                /**
                 * 普通关注事件
                 */
                agentProducer.sendMemberSubMsg(fromUserName);
            } else if ("unsubscribe".equals(eventType)) {
                log.info("取消关注事件：toUserName{}、fromUserName{}", toUserName, fromUserName);
            }
        }
        return result;
    }

    /**
     * 组装图文消息（懒得封装对象转XML方法，直接字符串拼装，大伙勿喷）
     * @param toUserName    开发者微信号
     * @param fromUserName  接收人openId
     * @param title         图文消息上的备注
     * @param description   图文消息上的备注
     * @param picUrl        图文消息上的图片
     * @param url           点击图文消息跳转的路径
     * @return
     */
    public static String imgTextMsg(String toUserName, String fromUserName, String title, String description, String picUrl, String url){
        return "<xml>"
                + "<ToUserName><![CDATA["+fromUserName+"]]></ToUserName>"
                + "<FromUserName><![CDATA["+toUserName+"]]></FromUserName>"
                + "<CreateTime>"+new Date().getTime()+"</CreateTime>"
                + "<MsgType><![CDATA[news]]></MsgType>"
                + "<ArticleCount>1</ArticleCount>"
                + "<Articles>"
                + "<item>"
                + "<Title><![CDATA["+title+"]]></Title>"
                + "<Description><![CDATA["+description+"]]></Description>"
                + "<PicUrl><![CDATA["+picUrl+"]]></PicUrl>"
                + "<Url><![CDATA["+url+"]]></Url>"
                + "</item>"
                + "</Articles>"
                + "</xml>";
    }

    /**
     * 解析微信发来的请求（XML）
     *
     * @param request 请求
     * @return map
     * @throws Exception 异常
     */
    public static Map<String, String> xmlToMap(HttpServletRequest request) {
        // 将解析结果存储在HashMap中
        Map<String, String> map = new HashMap<>(16);
        // 从request中取得输入流
        try (InputStream inputStream = request.getInputStream()) {
            System.out.println("获取输入流");
            // 读取输入流
            SAXReader reader = new SAXReader();
            Document document = reader.read(inputStream);
            // 得到xml根元素
            Element root = document.getRootElement();
            // 得到根元素的所有子节点
            List<Element> elementList = root.elements();

            // 遍历所有子节点
            for (Element e : elementList) {
                System.out.println(e.getName() + " | " + e.getText());
                map.put(e.getName(), e.getText());
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return map;
    }

    /**
     * 参数排序
     *
     * @param token     服务器配置，自定义的Token
     * @param timestamp timestamp
     * @param nonce     nonce
     * @return 排序后拼接字符串
     */
    public static String sort(String token, String timestamp, String nonce) {
        String[] strArray = {token, timestamp, nonce};
        Arrays.sort(strArray);
        StringBuilder sb = new StringBuilder();
        for (String str : strArray) {
            sb.append(str);
        }
        return sb.toString();
    }

    /**
     * 字符串进行shal加密
     *
     * @param str 字符串
     * @return 密文
     */
    public static String shal(String str) {
        try {
            MessageDigest digest = MessageDigest.getInstance("SHA-1");
            digest.update(str.getBytes());
            byte messageDigest[] = digest.digest();

            StringBuilder hexString = new StringBuilder();
            // 字节数组转换为 十六进制 数
            for (int i = 0; i < messageDigest.length; i++) {
                String shaHex = Integer.toHexString(messageDigest[i] & 0xFF);
                if (shaHex.length() < 2) {
                    hexString.append(0);
                }
                hexString.append(shaHex);
            }
            return hexString.toString();

        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
        return "";
    }

}