package com.doumee.core.wx;

import cn.hutool.core.util.RandomUtil;
import cn.hutool.core.util.XmlUtil;
import cn.hutool.crypto.digest.DigestUtil;
import cn.hutool.http.HttpUtil;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

import java.math.BigDecimal;
import java.math.RoundingMode;
import java.util.*;

/**
 * 微信公众号 JSAPI 支付（V2）
 */
@Component
@Slf4j
public class WxJsapiPayUtil {

    private static final String UNIFIED_ORDER_URL = "https://api.mch.weixin.qq.com/pay/unifiedorder";
    private static final String ORDER_QUERY_URL = "https://api.mch.weixin.qq.com/pay/orderquery";

    @Value("${wx.pay.appId:}")
    private String appId;
    @Value("${wx.pay.mchId:}")
    private String mchId;
    @Value("${wx.pay.mchKey:}")
    private String mchKey;
    @Value("${wx.pay.notifyUrl:}")
    private String notifyUrl;

    public Map<String, String> createJsapiOrder(String orderNo, String openid, String body, BigDecimal amountYuan, String clientIp) {
        int totalFee = amountYuan.multiply(BigDecimal.valueOf(100)).setScale(0, RoundingMode.HALF_UP).intValue();
        Map<String, String> params = new TreeMap<>();
        params.put("appid", appId);
        params.put("mch_id", mchId);
        params.put("nonce_str", RandomUtil.randomString(32));
        params.put("body", StringUtils.defaultIfBlank(body, "商户缴费"));
        params.put("out_trade_no", orderNo);
        params.put("total_fee", String.valueOf(totalFee));
        params.put("spbill_create_ip", StringUtils.defaultIfBlank(clientIp, "127.0.0.1"));
        params.put("notify_url", notifyUrl);
        params.put("trade_type", "JSAPI");
        params.put("openid", openid);
        params.put("sign", sign(params));

        String xml = mapToXml(params);
        String respXml = HttpUtil.post(UNIFIED_ORDER_URL, xml);
        Map<String, String> resp = xmlToMap(respXml);
        if (!"SUCCESS".equals(resp.get("return_code")) || !"SUCCESS".equals(resp.get("result_code"))) {
            throw new RuntimeException(StringUtils.defaultIfBlank(resp.get("err_code_des"), resp.get("return_msg")));
        }
        String prepayId = resp.get("prepay_id");
        return buildJsapiPayParams(prepayId);
    }

    public Map<String, String> queryOrder(String orderNo) {
        Map<String, String> params = new TreeMap<>();
        params.put("appid", appId);
        params.put("mch_id", mchId);
        params.put("out_trade_no", orderNo);
        params.put("nonce_str", RandomUtil.randomString(32));
        params.put("sign", sign(params));
        String respXml = HttpUtil.post(ORDER_QUERY_URL, mapToXml(params));
        return xmlToMap(respXml);
    }

    public boolean verifyNotifySign(Map<String, String> data) {
        if (data == null || !data.containsKey("sign")) {
            return false;
        }
        String sign = data.get("sign");
        Map<String, String> copy = new TreeMap<>(data);
        copy.remove("sign");
        return sign.equals(sign(copy));
    }

    public Map<String, String> parseNotifyXml(String xml) {
        return xmlToMap(xml);
    }

    private Map<String, String> buildJsapiPayParams(String prepayId) {
        Map<String, String> pay = new LinkedHashMap<>();
        pay.put("appId", appId);
        pay.put("timeStamp", String.valueOf(System.currentTimeMillis() / 1000));
        pay.put("nonceStr", RandomUtil.randomString(32));
        pay.put("package", "prepay_id=" + prepayId);
        pay.put("signType", "MD5");
        Map<String, String> signMap = new TreeMap<>();
        signMap.put("appId", pay.get("appId"));
        signMap.put("timeStamp", pay.get("timeStamp"));
        signMap.put("nonceStr", pay.get("nonceStr"));
        signMap.put("package", pay.get("package"));
        signMap.put("signType", pay.get("signType"));
        pay.put("paySign", sign(signMap));
        return pay;
    }

    private String sign(Map<String, String> params) {
        StringBuilder sb = new StringBuilder();
        for (Map.Entry<String, String> e : params.entrySet()) {
            if (StringUtils.isNotBlank(e.getValue())) {
                sb.append(e.getKey()).append("=").append(e.getValue()).append("&");
            }
        }
        sb.append("key=").append(mchKey);
        return DigestUtil.md5Hex(sb.toString()).toUpperCase();
    }

    private String mapToXml(Map<String, String> params) {
        StringBuilder sb = new StringBuilder("<xml>");
        for (Map.Entry<String, String> e : params.entrySet()) {
            sb.append("<").append(e.getKey()).append("><![CDATA[")
                    .append(e.getValue()).append("]]></").append(e.getKey()).append(">");
        }
        sb.append("</xml>");
        return sb.toString();
    }

    @SuppressWarnings("unchecked")
    private Map<String, String> xmlToMap(String xml) {
        Map<String, String> map = new HashMap<>();
        if (StringUtils.isBlank(xml)) {
            return map;
        }
        Map<String, Object> raw = XmlUtil.xmlToMap(xml);
        for (Map.Entry<String, Object> e : raw.entrySet()) {
            map.put(e.getKey(), e.getValue() == null ? null : String.valueOf(e.getValue()));
        }
        return map;
    }
}