package com.fzzy.igds.dzhwk.v1.util;

import com.ruoyi.common.utils.StringUtils;
import lombok.extern.slf4j.Slf4j;

import javax.crypto.Cipher;
import java.io.ByteArrayOutputStream;
import java.security.KeyFactory;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.Arrays;
import java.util.Base64;

@Slf4j
public class ApiV1Utils {


    public static final String KEY_ALGORITHM = "RSA";
    public static final String PRIVATE_KEY = "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";

    private static final String CHARSET = "utf-8";

    private static final int RESERVE_BYTES = 11;

    private static final int KEYSIZE = 1024;// 密钥位数

    // 2048 bits 的 RSA 密钥对，最大解密密文大小
    private static final int MAX_DECRYPT_BLOCK = KEYSIZE / 8;

    // 2048 bits 的 RSA 密钥对，最大加密明文大小
    private static final int MAX_ENCRYPT_BLOCK = MAX_DECRYPT_BLOCK - RESERVE_BYTES;

    // 获取公钥
    public static PublicKey getPublicKey(String publicKeyString) throws Exception {
        byte[] publicKeyByte = Base64.getDecoder().decode(publicKeyString);
        X509EncodedKeySpec keySpec = new X509EncodedKeySpec(publicKeyByte);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        return keyFactory.generatePublic(keySpec);
    }

    // 获取私钥
    public static PrivateKey getPrivateKey(String privateKeyString) throws Exception {
        byte[] privateKeyByte = Base64.getDecoder().decode(privateKeyString);
        PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(privateKeyByte);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        return keyFactory.generatePrivate(keySpec);
    }

    /**
     * 私钥解密
     *
     * @param secretText    待解密的密文字符串
     * @param privateKeyStr 私钥
     * @return 解密后的明文
     */
    public static String decrypt(String secretText, String privateKeyStr) {
        try {
            if (StringUtils.isEmpty(privateKeyStr)) {
                privateKeyStr = PRIVATE_KEY;
            }
            // 生成私钥
            Cipher cipher = Cipher.getInstance(KEY_ALGORITHM);
            cipher.init(Cipher.DECRYPT_MODE, getPrivateKey(privateKeyStr));
            // 密文解码
            byte[] data = Base64.getDecoder().decode(secretText);

            // 返回UTF-8编码的解密信息
            int inputLen = data.length;
            ByteArrayOutputStream out = new ByteArrayOutputStream();
            int offSet = 0;
            byte[] cache;
            int i = 0;
            // 对数据分段解密
            while (inputLen - offSet > 0) {
                if (inputLen - offSet > MAX_DECRYPT_BLOCK) {
                    cache = cipher.doFinal(data, offSet, MAX_DECRYPT_BLOCK);
                } else {
                    cache = cipher.doFinal(data, offSet, inputLen - offSet);
                }
                out.write(cache, 0, cache.length);
                i++;
                offSet = i * MAX_DECRYPT_BLOCK;
            }
            out.close();
            return out.toString(CHARSET);
        } catch (Exception e) {
            throw new RuntimeException("解密字符串[" + secretText + "]时遇到异常", e);
        }
    }

    /**
     * 公钥加密
     *
     * @param text         待加密的明文字符串
     * @param publicKeyStr 公钥
     * @return 加密后的密文
     */
    public static String encrypt(String text, String publicKeyStr) {
        String result = "";
        try {
//            log.info("明文字符串为:[{}]", text);
            // 加密
            Cipher cipher = Cipher.getInstance(KEY_ALGORITHM);
            cipher.init(Cipher.ENCRYPT_MODE, getPublicKey(publicKeyStr));
            byte[] textArray = text.getBytes();
            int textLength = textArray.length;
//            log.info("加密字节数={}", textLength);
            // 最大加密字节数，超出最大字节数需要分组加密
            int MAX_ENCRYPT_BLOCK = 117;
            // 标识
            int offSet = 0;
            byte[] resultBytes = {};
            byte[] cache = {};
            while (textLength - offSet > 0) {
                if (textLength - offSet > MAX_ENCRYPT_BLOCK) {
                    cache = cipher.doFinal(textArray, offSet, MAX_ENCRYPT_BLOCK);
                    offSet += MAX_ENCRYPT_BLOCK;
                } else {
                    cache = cipher.doFinal(textArray, offSet, textLength - offSet);
                    offSet = textLength;
                }
                resultBytes = Arrays.copyOf(resultBytes, resultBytes.length + cache.length);
                System.arraycopy(cache, 0, resultBytes, resultBytes.length - cache.length, cache.length);
            }
            result = Base64.getEncoder().encodeToString(resultBytes);
        } catch (Exception e) {
            throw new RuntimeException("加密字符串[" + text + "]时遇到异常", e);
        }
        return result;
    }

    public static void main(String[] args) {
        String pri = "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";
        String s = "{\"sign\":\"5363\",\"deptId\":\"5363_001\",\"reqDate\":\"2025-01-22 17:16:23\",\"data\":[{\"jcdj\":\"202501220001\",\"jcsj\":\"2025-01-22 17:16:23\",\"hwdm\":\"100010101\",\"cfww\":17.5,\"cfws\":75.5,\"cfnw\":17.5,\"cfns\":75.5,\"lszgw\":17.5,\"lszdw\":17.5,\"lspjw\":17.5,\"lswdzjh\":\"27.7,1,1,1|25.1,1,1,2|24.6,1,1,3|26.3,1,2,1|19.3,1,2,2|19.3,1,2,3|27.7,2,1,1|25.1,2,1,2|24.6,2,1,3|26.3,2,2,1|19.3,2,2,2|19.3,2, 2,3\",\"weather\":\"晴\",\"jcr\":\"检测人\",\"remarks\":\"备注信息\"},{\"jcdj\":\"202501220001\",\"jcsj\":\"2025-01-22 17:16:23\",\"hwdm\":\"100010101\",\"cfww\":17.5,\"cfws\":75.5,\"cfnw\":17.5,\"cfns\":75.5,\"lszgw\":17.5,\"lszdw\":17.5,\"lspjw\":17.5,\"lswdzjh\":\"27.7,1,1,1|25.1,1,1,2|24.6,1,1,3|26.3,1,2,1|19.3,1,2,2|19.3,1,2,3|27.7,2,1,1|25.1,2,1,2|24.6,2,1,3|26.3,2,2,1|19.3,2,2,2|19.3,2, 2,3\",\"weather\":\"晴\",\"jcr\":\"检测人\",\"remarks\":\"备注信息111\"}]}";
        String pub = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCRsamMiP5Op2JJtp3+IIJADFYhL256ZW0KsOkMHruJ3hVwgvoimPHKuUWRI/CS365v4BwUzzfBRdbECMFsLA1e1FHPPA0uSsAIuSVwRzHXG4drX7ZCDa9GFZ+qyIFAU25j2e2PC9olvKbGLBfZ8cL1FLXGxSVyDCX4t/UMZdDULwIDAQAB";
        log.info("明文字符串:{}", s);
        log.info("公钥:{}", pub);
        String rsaPublicKey = encrypt(s, pub);
        log.info("公钥加密后密文:{}", rsaPublicKey);

        String decrypt = decrypt(rsaPublicKey, pri);
        log.info("解密后明文:{}", decrypt);

    }

}