package com.ruoyi.common.utils;

import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;

import javax.crypto.Cipher;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
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.Base64;

@Slf4j
@Component
public class RSAPublicKeyExample {


    /**
     * 数据解密
     *
     * @param encryptedData
     * @return
     */
    public String decryptedData(String encryptedData, String pri_key) {
        String privateKeyString = "私钥的Base64编码字符串"; // 后端私钥的Base64编码字符串

        try {
            // 将私钥Base64编码字符串转换为PrivateKey对象
            byte[] privateKeyBytes = Base64.getDecoder().decode(pri_key);
            PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(privateKeyBytes);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PrivateKey privateKey = keyFactory.generatePrivate(keySpec);

            // 使用私钥解密数据
            Cipher decryptCipher = Cipher.getInstance("RSA");
            decryptCipher.init(Cipher.DECRYPT_MODE, privateKey);
            byte[] decryptedBytes = decryptCipher.doFinal(Base64.getDecoder().decode(encryptedData));

            // 解密后的数据
            String decryptedData = new String(decryptedBytes);
            System.out.println("解密后的数据：" + decryptedData);
            return decryptedData;
        } catch (Exception e) {
            log.error("解密报错了:{}", e.getMessage());
        }
        return null;
    }

    /**
     * 要加密的明文数据
     *
     * @param plainText
     * @return
     */
    public String encryptedData(String plainText, String pub_key) {
        log.error("需要加密的数据：{}", plainText);
        try {

            byte[] publicKeyBytes = Base64.getDecoder().decode(pub_key);
            X509EncodedKeySpec keySpec = new X509EncodedKeySpec(publicKeyBytes);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PublicKey publicKey = keyFactory.generatePublic(keySpec);

            // 使用公钥加密数据
            Cipher encryptCipher = Cipher.getInstance("RSA");
            encryptCipher.init(Cipher.ENCRYPT_MODE, publicKey);
            byte[] encryptedBytes = encryptCipher.doFinal(plainText.getBytes());

            // 将加密后的数据转换为Base64编码的字符串
            String encryptedText = Base64.getEncoder().encodeToString(encryptedBytes);
            log.error("Base64加密后的数据：{}", encryptedText);
            encryptedText = URLEncoder.encode(encryptedText, StandardCharsets.UTF_8.toString());
            log.error("URLEncoder编码后的数据：{}", encryptedText);
            String decodedString = URLDecoder.decode(encryptedText, "UTF-8");
            log.error("URLEncoder解码后的数据：{}", decodedString);
            return encryptedText;
        } catch (Exception e) {
            log.error("加密失败了:{}", e.getMessage());
        }
        return null;
    }

    public static void main(String[] args) {
        String decodedString = null;
        try {
            decodedString = URLDecoder.decode("0902%E4%BB%BB%E5%8A%A1%E6%B5%8B%E8%AF%95--------", "UTF-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        System.out.println(decodedString);
    }

}