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 {


    public static String encryptedData(String plainText, String pubKey) {
        try {
            byte[] publicKeyBytes = Base64.getDecoder().decode(pubKey);
            X509EncodedKeySpec keySpec = new X509EncodedKeySpec(publicKeyBytes);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PublicKey publicKey = keyFactory.generatePublic(keySpec);

            Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
            cipher.init(Cipher.ENCRYPT_MODE, publicKey);
            byte[] encryptedBytes = cipher.doFinal(plainText.getBytes(StandardCharsets.UTF_8));

            // Base64 编码（必须保留）
            String encryptedText = Base64.getEncoder().encodeToString(encryptedBytes);

            // 可选：如果用于 URL 传输，再进行 URL 编码
            return URLEncoder.encode(encryptedText, StandardCharsets.UTF_8.toString());
        } catch (Exception e) {
            System.err.println("加密失败: " + e.getMessage());
            e.printStackTrace();
            return null;
        }
    }

    /**
     * RSA 私钥解密（解密 Base64 编码后的密文，支持 URL 解码）
     */
    public static String decryptedData(String encryptedData, String priKey) {
        try {
            // 可选：先 URL 解码（如果加密前做了 URLEncoder）
            String base64Encrypted = URLDecoder.decode(encryptedData, StandardCharsets.UTF_8.toString());

            // Base64 解码
            byte[] encryptedBytes = Base64.getDecoder().decode(base64Encrypted);

            byte[] privateKeyBytes = Base64.getDecoder().decode(priKey);
            PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(privateKeyBytes);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PrivateKey privateKey = keyFactory.generatePrivate(keySpec);

            Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
            cipher.init(Cipher.DECRYPT_MODE, privateKey);
            byte[] decryptedBytes = cipher.doFinal(encryptedBytes);

            return new String(decryptedBytes, StandardCharsets.UTF_8);
        } catch (Exception e) {
            System.err.println("解密失败: " + e.getMessage());
            e.printStackTrace();
            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);
    }

}