package com.fzzy.gateway.hx2023.util;

import cn.hutool.crypto.digest.MD5;
import lombok.Data;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;
import org.apache.commons.lang3.StringUtils;

import javax.servlet.http.HttpServletRequest;
import java.io.UnsupportedEncodingException;
import java.nio.charset.StandardCharsets;
import java.security.interfaces.RSAPrivateKey;
import java.util.*;

/**
 * 签名工具类
 */
@Slf4j
@Data
public class OpenApiSignatureUtils {

    public static String getMd5Content(String content, String charset) {
        try {
            byte[] md5 = MD5.create().digest(content);
            return new String(md5, charset);
        } catch (UnsupportedEncodingException e) {
            log.error("getMd5Content(),exception happens.", e);
        }
        return null;
    }

    public static String getSignContent(final Map<String, String> sortedParams) {
        StringBuffer content = new StringBuffer();
        List<String> keys = new ArrayList(sortedParams.keySet());
        Collections.sort(keys);
        int index = 0;
        for (int i = 0; i < keys.size(); i++) {
            String key = keys.get(i);
            String value = sortedParams.get(key);
            if (key.equals("sign") || key.equals("sign_type")) {
                continue;
            }
            if (StringUtils.isNotEmpty(key) && StringUtils.isNotEmpty(value)) {
                content.append((index == 0 ? "" : "&") + key + "=" + value);
                index++;
            }
        }
        return content.toString();
    }

    public static String getSignContentWithQuotes(final Map<String, String> sortedParams) {
        StringBuffer content = new StringBuffer();
        List<String> keys = new ArrayList<String>(sortedParams.keySet());
        Collections.sort(keys);
        int index = 0;
        for (int i = 0; i < keys.size(); i++) {
            String key = keys.get(i);
            String value = sortedParams.get(key);
            if (StringUtils.isNotEmpty(key) && StringUtils.isNotEmpty(value)) {
                content.append((index == 0 ? "" : "&") + key + "=\"" + value + "\"");
                index++;
            }
        }
        return content.toString();
    }

    public static boolean doCheckV1(String appId, Map<String, String> params, String charset, String publicKey, String privateKye) throws Exception {
        String sign = params.get("sign");
        String content = getSignCheckContentWithoutSign(params);
        return doRsaCheckContent(appId, content, sign, charset, publicKey, privateKye);
    }

    public static String doSignByBase64(String appId, String content, String charset, String publicKey, String privateKye) throws RuntimeException {
        try {
            byte[] signData = OpenApiRsaSigner.encrypt((RSAPrivateKey) OpenApiRsaSigner.getInstance(appId, publicKey, privateKye).getPrivateKey(), content.getBytes(charset));
            //return new String(signData, charset);
            return new String(Base64.encodeBase64(signData), StandardCharsets.UTF_8);
        } catch (Exception e) {
            throw new RuntimeException("key=" + appId + ";content=" + content + ";charset=" + charset, e);
        }
    }

    public static String doSignByHex(String appId, String content, String charset, String publicKey, String privateKye) throws RuntimeException {
        try {
            byte[] signData = OpenApiRsaSigner.encrypt((RSAPrivateKey) OpenApiRsaSigner.getInstance(appId, publicKey, privateKye).getPrivateKey(), content.getBytes(charset));
            //return new String(signData, charset);
            return new String(Hex.encodeHex(signData));
        } catch (Exception e) {
            throw new RuntimeException("key=" + appId + ";content=" + content + ";charset=" + charset, e);
        }
    }

    public static String doSignByTranscode(String appId, String content, String charset, String publicKey, String privateKye) throws RuntimeException {
        try {
            byte[] signData = OpenApiRsaSigner.encrypt((RSAPrivateKey) OpenApiRsaSigner.getInstance(appId, publicKey, privateKye).getPrivateKey(), content.getBytes(charset));
            return new String(signData, charset);
            //return new String(Base64.encodeBase64(signData), StandardCharsets.UTF_8);
        } catch (Exception e) {
            throw new RuntimeException("key=" + appId + ";content=" + content + ";charset=" + charset, e);
        }
    }

    public static String getSignCheckContentWithoutSign(Map<String, String> params) {
        if (params == null) {
            return null;
        }
        params.remove("sign");
        params.remove("sign_type");

        StringBuffer content = new StringBuffer();
        List<String> keys = new ArrayList<String>(params.keySet());
        Collections.sort(keys);

        for (int i = 0; i < keys.size(); i++) {
            String key = keys.get(i);
            String value = params.get(key);
            content.append((i == 0 ? "" : "&") + key + "=" + value);
        }
        return content.toString();
    }

    public static boolean doRsaCheckContent(String appId, String content, String sign,
                                            String charset, String publicKey, String privateKye) throws RuntimeException {
        try {
            RSAPrivateKey privateKey = (RSAPrivateKey) OpenApiRsaSigner.getInstance(appId, publicKey, privateKye).getPrivateKey();
            return OpenApiRsaSigner.verify(content, sign, privateKey);
        } catch (Exception e) {
            throw new RuntimeException("key=" + appId + ";content=" + content + ";sign=" + sign + ";charset="
                    + charset, e);
        }
    }

    public static boolean doCheckByBase64(String appId, String content, String sign,
                                          String charset, String publicKey, String privateKye) throws RuntimeException {
        try {
            RSAPrivateKey privateKey = (RSAPrivateKey) OpenApiRsaSigner.getInstance(appId, publicKey, privateKye).getPrivateKey();
            return OpenApiRsaSigner.verify(content, new String(Base64.decodeBase64(sign), StandardCharsets.UTF_8), privateKey);
        } catch (Exception e) {
            throw new RuntimeException("key=" + appId + ";content=" + content + ";sign=" + sign + ";charset="
                    + charset, e);
        }
    }

    public static boolean doCheckByHex(String appId, String content, String sign,
                                       String charset, String publicKey, String privateKye) throws RuntimeException {
        try {
            RSAPrivateKey privateKey = (RSAPrivateKey) OpenApiRsaSigner.getInstance(appId, publicKey, privateKye).getPrivateKey();
            return OpenApiRsaSigner.verify(content, new String(Hex.decodeHex(sign.toCharArray())), privateKey);
        } catch (Exception e) {
            throw new RuntimeException("key=" + appId + ";content=" + content + ";sign=" + sign + ";charset="
                    + charset, e);
        }
    }

    public static boolean doCheckByTranscode(String appId, String content, String sign,
                                             String charset, String publicKey, String privateKye) throws RuntimeException {
        try {
            RSAPrivateKey privateKey = (RSAPrivateKey) OpenApiRsaSigner.getInstance(appId, publicKey, privateKye).getPrivateKey();
            return OpenApiRsaSigner.verify(content, sign, privateKey);
        } catch (Exception e) {
            throw new RuntimeException("key=" + appId + ";content=" + content + ";sign=" + sign + ";charset="
                    + charset, e);
        }
    }

    /**
     * 获取请求参数
     *
     * @param request
     * @return
     */
    public static Map<String, String> getParameterMap(HttpServletRequest request) {
        Enumeration<String> parameters = request.getParameterNames();
        if (parameters == null) {
            return new HashMap<>();
        }

        HashMap resultMap = new HashMap<>();
        while (parameters.hasMoreElements()) {
            String key = parameters.nextElement();
            String value = request.getParameter(key);
            resultMap.put(key, value);
        }

        return resultMap;
    }

    /**
     * 测试逻辑
     *
     * @param args
     * @throws UnsupportedEncodingException
     */
    public static void testSign(String[] args) throws UnsupportedEncodingException {
        Map<String, String> sortedParams = new HashMap<String, String>();
        sortedParams.put("appId", "6e3d896b71b911eea5e50250f2000002");
//        sortedParams.put("method", "test");
//        sortedParams.put("format", "json");
//        sortedParams.put("charset", "utf-8");
//        sortedParams.put("sign_type", "RSA");
//        sortedParams.put("timestamp", "2019-01-01 00:00:00");
//        sortedParams.put("version", "1.0");
//        sortedParams.put("biz_content", "{\"name\":\"张三\",\"age\":18}");
    }
}