import cn.hutool.crypto.SmUtil;
import cn.hutool.crypto.asymmetric.SM2;
import cn.hutool.crypto.digest.SM3;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
import com.bskj.framework.license.model.LicenseInfo;
import java.nio.charset.StandardCharsets;
import java.util.Base64;

public class TestSignature {
    public static void main(String[] args) throws Exception {
        // 读取现有的许可证文件
        ObjectMapper mapper = new ObjectMapper();
        mapper.registerModule(new JavaTimeModule());
        
        LicenseInfo license = mapper.readValue(new java.io.File("license.json"), LicenseInfo.class);
        
        // 加载私钥
        String privateKeyContent = new String(java.nio.file.Files.readAllBytes(java.nio.file.Paths.get("private.key")));
        privateKeyContent = privateKeyContent.replace("-----BEGIN PRIVATE KEY-----", "")
                .replace("-----END PRIVATE KEY-----", "")
                .replaceAll("\\s", "");
        
        // 加载公钥
        String publicKeyContent = new String(java.nio.file.Files.readAllBytes(java.nio.file.Paths.get("public.key")));
        publicKeyContent = publicKeyContent.replace("-----BEGIN PUBLIC KEY-----", "")
                .replace("-----END PUBLIC KEY-----", "")
                .replaceAll("\\s", "");
        
        byte[] privateKeyBytes = Base64.getDecoder().decode(privateKeyContent);
        byte[] publicKeyBytes = Base64.getDecoder().decode(publicKeyContent);
        SM2 sm2 = SmUtil.sm2(privateKeyBytes, publicKeyBytes);
        
        // 重新生成签名数据
        String signatureData = createSignatureData(license);
        System.out.println("Signature data: " + signatureData);
        System.out.println("Data length: " + signatureData.length());
        
        // Generate new signature
        SM3 sm3 = new SM3();
        byte[] hashedData = sm3.digest(signatureData.getBytes(StandardCharsets.UTF_8));
        byte[] signatureBytes = sm2.sign(hashedData);
        String newSignature = Base64.getEncoder().encodeToString(signatureBytes);
        
        System.out.println("Original signature: " + license.getSignature());
        System.out.println("New signature: " + newSignature);
        
        // Verify new signature
        boolean isValid = sm2.verify(hashedData, signatureBytes);
        System.out.println("Signature valid: " + isValid);
        
        // Update license file
        license.setSignature(newSignature);
        mapper.writeValue(new java.io.File("license_fixed.json"), license);
        System.out.println("Fixed license saved to license_fixed.json");
    }
    
    private static String createSignatureData(LicenseInfo licenseInfo) {
        StringBuilder sb = new StringBuilder();
        
        appendField(sb, "licenseId", licenseInfo.getLicenseId());
        appendField(sb, "customerName", licenseInfo.getCustomerName());
        appendField(sb, "productName", licenseInfo.getProductName());
        appendField(sb, "productVersion", licenseInfo.getProductVersion());
        appendField(sb, "createdTime", licenseInfo.getCreatedTime());
        appendField(sb, "startTime", licenseInfo.getStartTime());
        appendField(sb, "endTime", licenseInfo.getEndTime());
        appendField(sb, "strategy", licenseInfo.getStrategy());
        appendField(sb, "gracePeriodDays", licenseInfo.getGracePeriodDays());
        appendField(sb, "warningDays", licenseInfo.getWarningDays());
        appendField(sb, "maxUsers", licenseInfo.getMaxUsers());
        
        return sb.toString();
    }
    
    private static void appendField(StringBuilder sb, String fieldName, Object value) {
        sb.append(fieldName).append("=");
        if (value != null) {
            sb.append(value.toString());
        }
        sb.append(";");
    }
}