package com.engine.salary.util;

import lombok.extern.slf4j.Slf4j;
import org.apache.commons.codec.binary.Base64;

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import java.net.URLEncoder;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SignatureException;
import java.util.HashMap;
import java.util.Map;
import java.util.TreeMap;
import java.util.UUID;

/**
 * @author jie.zhou
 * @version 1.0
 * @date 2021/1/14 15:27
 */
@Slf4j
public class SingnatureData {

    /**
     * 初始化延签头信息(GET)
     *
     * @param param
     * @param appKey
     * @param appSecret
     * @return
     */
    public static Map<String, String> initHeader(Map<String, String> param, String appKey, String appSecret) {
        String version = "1.0.0";
        long timestamp = System.currentTimeMillis();
        String nonce = UUID.randomUUID().toString().replace("-", "");
        Map<String, String> head = new HashMap<String, String>();
        if (param != null && param.size() > 0) head.putAll(param);
        head.put("version", version);
        head.put("timestamp", Long.toString(timestamp));//TimeStamp
        head.put("appKey", appKey);//accessKeyID
        head.put("xReqNonce", nonce);//SignatureNonce
        String signature = getSign(head, appSecret, "UTF-8");
        head.put("signature", signature.trim());
        return head;
    }

    /***
     * 获取签名
     * @param params
     * @param appSecret
     * @param encoding
     * @return
     */
    public static String getSign(Map<String, String> params, String appSecret, String encoding) {
        TreeMap<String, String> treeMap = new TreeMap<>();
        treeMap.put("appSecret", appSecret);

        for (Map.Entry<String, String> entry : params.entrySet()) {
            treeMap.put(entry.getKey(), entry.getValue().toString());
        }
        StringBuilder builder = new StringBuilder();
        for (Object parameter : treeMap.values()) {
            if (parameter != null) {
                builder.append(parameter.toString());
            }
        }
        String signStr = null;
        try {
            signStr = sign(URLEncoder.encode(builder.toString(), encoding), appSecret);
        } catch (Exception e) {
            log.error("获取签名失败", e);
        }
        return signStr;
    }

    public static String sign(String data, String appSecret) throws SignatureException {
        try {
            Mac mac = Mac.getInstance("HmacSHA256");
            SecretKeySpec signingKey = new SecretKeySpec(appSecret.getBytes(), "HmacSHA256");
            mac.init(signingKey);
            byte[] signData = mac.doFinal(data.getBytes());
            return Base64.encodeBase64String(signData);
        } catch (NoSuchAlgorithmException e) {
            throw new SignatureException("平台不支持" + "HMAC_SHA256" + "摘要方式");
        } catch (InvalidKeyException e) {
            throw new SignatureException("Speicified access secret is not valid.");
        }
    }
}