package cn.iocoder.yudao.framework.security.core.util;

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;

/**
 * RSA加密解密
 *
 * @author jayden
 **/
public class RsaUtils
{
    // Rsa 私钥
    public static String privateKey = "MIIBVQIBADANBgkqhkiG9w0BAQEFAASCAT8wggE7AgEAAkEA4TgukNwXxZ16sdy26bXMlCLLZMz4PlVYEQjGf2S/P0YvkDqSLxxaTTFpy83ZGizimYebnvfLtMmLzG/9gemVuwIDAQABAkA7X3E/NRZ7PTnEO9hookmtX8LY7wQegqc1zmdt3CRizGJRB7/9LzDqvnOIvqqm+EoiZLjUUNKVkOom0FI2u32hAiEA8UtmegwiMaqmE4xrjqocLRAR0aVWV7i4fSTcSvLVCcsCIQDu8fvGY9wfVKEGgyfcJHuORowDAbYYXOulxC6sEW7l0QIgE1J2Yk+WbWO86NPVyRbWKsWep6sVvvCL1XmeKmJHrQECIQDGAEmVbTyDzdodjmNiXezwye7NswZVC/LNi1LtjQircQIhAIpF1rvPvxXkE7KvWTePrCWeU/+c6e1ylG7sPYumc1cx";

    /**
     * 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(512);
        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;
        }
    }
}
