package com.zy.system.entity.license;

import de.schlichtherle.license.*;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.text.DateFormat;
import java.text.MessageFormat;
import java.text.SimpleDateFormat;
import java.util.Base64;
import java.util.prefs.Preferences;

/**
 * License校验类
 */
public class LicenseVerify {
    private static Logger logger = LogManager.getLogger(LicenseVerify.class);

    /**
     * 安装License证书
     */
    public synchronized LicenseContent install(LicenseVerifyParam param, String license) {
        LicenseContent result = null;
        DateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

        //1. 安装证书
        try {
            LicenseParam licenseParam = initLicenseParam(param);
            LicenseManager licenseManager = LicenseManagerHolder.getInstance(licenseParam);
            licenseManager.uninstall();

            File tempFileFromBase64 = createTempFileFromBase64(license);
            result = licenseManager.install(tempFileFromBase64);
            logger.info(MessageFormat.format("许可证加载成功，许可证有效期：{0} - {1}", format.format(result.getNotBefore()), format.format(result.getNotAfter())));
        } catch (Exception e) {
            logger.error("许可证加载失败！", e);
        }

        return result;
    }

    /**
     * 校验License证书
     */
    public boolean verify(){
        try {
            LicenseManager licenseManager = LicenseManagerHolder.getInstance(null);
            DateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

            LicenseContent licenseContent = licenseManager.verify();
            logger.info(MessageFormat.format("许可证校验通过，许可证有效期：{0} - {1}",format.format(licenseContent.getNotBefore()),format.format(licenseContent.getNotAfter())));
            return true;
        }catch (Exception e){
            logger.error("许可证校验失败！",e);
            return false;
        }
    }

    /**
     * 校验License证书并获取证书信息
     */
    public LicenseContent getVerifyInfo(){
        LicenseManager licenseManager = LicenseManagerHolder.getInstance(null);

        //校验证书
        try {
            LicenseContent licenseContent = licenseManager.verify();
            return licenseContent;
        }catch (Exception e){
            logger.error("许可证校验失败！",e);
            return null;
        }
    }

    /**
     * 初始化证书生成参数
     * @param param License校验类需要的参数
     * @return de.schlichtherle.license.LicenseParam
     */
    private LicenseParam initLicenseParam(LicenseVerifyParam param){
        Preferences preferences = Preferences.userNodeForPackage(LicenseVerify.class);

        CipherParam cipherParam = new DefaultCipherParam(param.getStorePass());

        KeyStoreParam publicStoreParam = new CustomKeyStoreParam(LicenseVerify.class
                ,param.getPublicKeysStorePath()
                ,param.getPublicAlias()
                ,param.getStorePass()
                ,null);

        return new DefaultLicenseParam(param.getSubject()
                ,preferences
                ,publicStoreParam
                ,cipherParam);
    }

    /**
     * 将Base64字符串转换为临时文件
     * @param base64String Base64编码的字符串
     * @param filePrefix 文件名前缀（例如 "license_"）
     * @param fileSuffix 文件后缀（例如 ".lic"）
     * @return 生成的临时File对象（自动在JVM退出时删除）
     * @throws IOException
     */
    public File base64ToTempFile(String base64String, String filePrefix, String fileSuffix)
            throws IOException {
        // 解码Base64
        byte[] decodedBytes = Base64.getDecoder().decode(base64String);
        // 创建临时文件
        Path tempPath = Files.createTempFile(filePrefix, fileSuffix);
        // 写入内容
        Files.write(tempPath, decodedBytes);
        // 设置JVM退出时自动删除
        tempPath.toFile().deleteOnExit();
        return tempPath.toFile();
    }

    public File createTempFileFromBase64(String base64Data) throws IOException {
        return base64ToTempFile(base64Data, "temp_license_", ".bin");
    }

}