package com.ltkj.common.utils.sign;

import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import java.security.*;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
/**
 * @Author: 西安路泰科技有限公司/lige
 * @Date: 2023/1/10 11:17
 */

/**
 * RSA加密解密
 *
 * @author ltkj
 **/
public class RsaUtils {
    // Rsa 私钥
    public static String privateKey = "MIIBVAIBADANBgkqhkiG9w0BAQEFAASCAT4wggE6AgEAAkEAqhHyZfSsYourNxaY"
            + "7Nt+PrgrxkiA50efORdI5U5lsW79MmFnusUA355oaSXcLhu5xxB38SMSyP2KvuKN"
            + "PuH3owIDAQABAkAfoiLyL+Z4lf4Myxk6xUDgLaWGximj20CUf+5BKKnlrK+Ed8gA"
            + "kM0HqoTt2UZwA5E2MzS4EI2gjfQhz5X28uqxAiEA3wNFxfrCZlSZHb0gn2zDpWow"
            + "cSxQAgiCstxGUoOqlW8CIQDDOerGKH5OmCJ4Z21v+F25WaHYPxCFMvwxpcw99Ecv"
            + "DQIgIdhDTIqD2jfYjPTY8Jj3EDGPbH2HHuffvflECt3Ek60CIQCFRlCkHpi7hthh"
            + "YhovyloRYsM+IS9h/0BzlEAuO0ktMQIgSPT3aFAgJYwKpqRYKlLDVcflZFCKY7u3"
            + "UP8iWi1Qw0Y=";

    /**
     * 私钥解密
     *
     * @param text             待解密的文本
     * @return 解密后的文本
     */
    public static String decryptByPrivateKey(String text) throws Exception {
        return decryptByPrivateKey(privateKey, text);
    }

    /**
     * 公钥解密
     *
     * @param publicKeyString 公钥
     * @param text            待解密的信息
     * @return 解密后的文本
     */
    public static String decryptByPublicKey(String publicKeyString, String text) throws Exception {
        X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyString));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, publicKey);
        byte[] result = cipher.doFinal(Base64.decodeBase64(text));
        return new String(result);
    }

    /**
     * 私钥加密
     *
     * @param privateKeyString 私钥
     * @param text             待加密的信息
     * @return 加密后的文本
     */
    public static String encryptByPrivateKey(String privateKeyString, String text) throws Exception {
        PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyString));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, privateKey);
        byte[] result = cipher.doFinal(text.getBytes());
        return Base64.encodeBase64String(result);
    }

    /**
     * 私钥解密
     *
     * @param privateKeyString 私钥
     * @param text             待解密的文本
     * @return 解密后的文本
     */
    public static String decryptByPrivateKey(String privateKeyString, String text) throws Exception {
        PKCS8EncodedKeySpec pkcs8EncodedKeySpec5 = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyString));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec5);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, privateKey);
        byte[] result = cipher.doFinal(Base64.decodeBase64(text));
        return new String(result);
    }

    /**
     * 公钥加密
     *
     * @param publicKeyString 公钥
     * @param text            待加密的文本
     * @return 加密后的文本
     */
    public static String encryptByPublicKey(String publicKeyString, String text) throws Exception {
        X509EncodedKeySpec x509EncodedKeySpec2 = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyString));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec2);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        byte[] result = cipher.doFinal(text.getBytes());
        return Base64.encodeBase64String(result);
    }

    /**
     * 构建RSA密钥对
     *
     * @return 生成后的公私钥信息
     */
    public static RsaKeyPair generateKeyPair() throws NoSuchAlgorithmException {
        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
        keyPairGenerator.initialize(1024);
        KeyPair keyPair = keyPairGenerator.generateKeyPair();
        RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic();
        RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate();
        String publicKeyString = Base64.encodeBase64String(rsaPublicKey.getEncoded());
        String privateKeyString = Base64.encodeBase64String(rsaPrivateKey.getEncoded());
        return new RsaKeyPair(publicKeyString, privateKeyString);
    }

    /**
     * RSA密钥对对象
     */
    public static class RsaKeyPair {
        private final String publicKey;
        private final String privateKey;

        public RsaKeyPair(String publicKey, String privateKey) {
            this.publicKey = publicKey;
            this.privateKey = privateKey;
        }

        public String getPublicKey() {
            return publicKey;
        }

        public String getPrivateKey() {
            return privateKey;
        }
    }
}