@Slf4j
public class MinioService {
    private final MinioConfig config;
    private MinioClient client;
    private final SimpleDateFormat format = new SimpleDateFormat("yyyyMMdd");
    public MinioService(com.doblue.smlt.config.MinioConfig config) {
        this.config = config;
        try{
            client = MinioClient.builder()
                    .endpoint(config.getHost())
                    .credentials(config.getAccessKey(), config.getSecretKey())
                    .build();
        }catch (Exception ex){
            log.error("Minio 初始化失败！Trace：");
            ex.printStackTrace();
        }
    }

    /**
     * 文件上传
     * @param file 文件
     * @param path minio 远程路径
     * @return 公网访问 url
     */
    public String upload(MultipartFile file, String path){
        try{
            return upload(file, path, file.getContentType());
        }catch (Exception ex){
            log.error("文件上传失败！Trace：");
            ex.printStackTrace();
            throw new UnknownException(ex.getMessage());
        }
    }

    /**
     * 文件上传
     * @param file 文件
     * @param path minio 远程路径
     * @param contentType 文件类型
     * @return 公网访问 url
     */
    public String upload(MultipartFile file, String path, String contentType)
            throws Exception {
        String filename = genPath(path, getExtension(file));
        PutObjectArgs args = PutObjectArgs.builder()
                .contentType(contentType)
                .object(filename)
                .bucket(config.getBucket())
                .stream(file.getInputStream(), file.getSize(), ObjectWriteArgs.MIN_MULTIPART_SIZE)
                .build();
        client.putObject(args);
        return minioPublicURL(filename);
    }

    /**
     * 根据完整 URL 来移除 minio 服务器中的对象
     * @param url 例：http://127.0.0.1:9000/furniture/materials/20230315/7375e567-d771-46a7-bccf-bb48886ab3d2.png
     */
    public void removeObjectByURL(String url){
        removeObject(extractObjectName(url));
    }

    /**
     * 根据对象名移除 minio 服务器中的对象
     * @param name 例：materials/20230315/7375e567-d771-46a7-bccf-bb48886ab3d2.png
     */
    public void removeObject(String name){
        try{
            RemoveObjectArgs args = RemoveObjectArgs.builder()
                    .bucket(config.getBucket())
                    .object(name)
                    .build();
            client.removeObject(args);
        }catch (Exception e){
            log.error("MinIO 文件删除错误：{}", e.getMessage());
            e.printStackTrace();
            throw new UnknownException(e.getMessage());
        }
    }

    /**
     * 获取对象文件公网访问 url
     * @param filename 对象名称
     * @return 公网访问 url
     */
    private String minioPublicURL(String filename) {
        return config.getHost() + '/' + config.getBucket() + "/" + filename;
    }

    /**
     * 生成对象路径
     * @param basicPath 根路径
     * @param extension 文件扩展名
     * @return basicPath/yyyyMMdd/uuid.extension
     */
    public String genPath(String basicPath, String extension){
        return basicPath + "/" + format.format(new Date()) + "/" + UUID.randomUUID() + extension;
    }

    /**
     * 获取文件的扩展名
     * @param file 文件
     * @return 例：.jpg
     */
    public String getExtension(MultipartFile file){
        return getExtension(file.getOriginalFilename());
    }
    /**
     * 获取文件的扩展名
     * @param name 文件名称
     * @return 例：.jpg
     */
    public String getExtension(String name){
        return name.substring(name.lastIndexOf('.'));
    }

    /**
     * 递归移除目录下所有文件
     * @param folder 目录
     */
    public void removeFolder(String folder){
        try{
            if (!folder.endsWith("/")){
                folder+="/";
            }
            Iterable<Result<Item>> results = client.listObjects(
                    ListObjectsArgs.builder()
                            .bucket(config.getBucket())
                            .prefix(folder)
                            .build());
            for (Result<Item> r : results) {
                Item item = r.get();
                if (item.isDir()){
                    removeFolder(item.objectName());
                }else {
                    removeObject(item.objectName());
                }
            }
        }catch (Exception ex){
            log.error("文件上传失败：");
            ex.printStackTrace();
            throw new UnknownException(ex.getMessage());
        }
    }

    /**
     * 下载文件，用于受保护的 minio 服务器
     * 此方法未测试
     */
    public GetObjectResponse download(String object){
        GetObjectArgs args = GetObjectArgs.builder()
                .bucket(config.getBucket())
                .object(object)
                .build();
        try{
            return client.getObject(args);
        }catch (Exception ex){
            log.error("MinIO 文件下载错误：");
            ex.printStackTrace();
            throw new UnknownException(ex.getMessage());
        }
    }

    /**
     * 根据url下载文件
     * 此方法未测试
     */
    public GetObjectResponse downloadByUrl(String url){
        return download(extractObjectName(url));
    }

    /**
     * 提取 url 中的 minio 对象路径
     * @param url 例：http://127.0.0.1:9000/furniture/materials/20230315/7375e567-d771-46a7-bccf-bb48886ab3d2.png
     * @return 例：/materials/20230315/7375e567-d771-46a7-bccf-bb48886ab3d2.png
     */
    public String extractObjectName(String url) {
        return url.substring(minioPublicURL("").length());
    }

    /**
     * 将一个对象拷贝到指定路径
     * @param objectName minio 中需要拷贝的对象
     * @param path minio 要拷贝到的路径
     * @return 拷贝后路径的公网访问 url
     */
    public String copy(String objectName, String path){
        String extension = getExtension(objectName);
        String targetObject = genPath(path, extension);
        CopyObjectArgs args = CopyObjectArgs.builder()
                .bucket(config.getBucket())
                .object(targetObject)
                .source(CopySource.builder()
                        .bucket(config.getBucket())
                        .object(objectName)
                        .build())
                .build();
        try{
            client.copyObject(args);
        }catch (Exception e){
            log.error("minIO 文件拷贝失败：");
            e.printStackTrace();
            throw new UnknownException(e.getMessage());
        }
        return minioPublicURL(targetObject);
    }

    /**
     * 通过 url 拷贝
     * @see MinioService#copy(String, String)
     */
    public String copyByUrl(String url, String path){
        return copy(extractObjectName(url), path);
    }
}