package com.dji.sample.media.util;

import java.io.*;
import java.nio.file.*;
import java.util.*;
import java.util.zip.*;

public class MinioFileDownloader {

    private final String bucketPath;

    public MinioFileDownloader(String bucketPath) {
        this.bucketPath = bucketPath;
    }

    public void downloadAndZipFolders(List<String> prefixes, String localSaveDir) throws Exception {
        // 创建目标文件夹路径并生成zip文件名
        Path localSavePath = Paths.get(localSaveDir);
        if (!Files.exists(localSavePath)) {
            Files.createDirectories(localSavePath);
        }
        String zipFileName = localSavePath.resolve("compressed_files.zip").toString();

        // 创建压缩文件输出流
        try (ZipOutputStream zos = new ZipOutputStream(new FileOutputStream(zipFileName))) {
            zos.setLevel(Deflater.BEST_COMPRESSION); // 使用最高压缩级别

            // 遍历每个前缀
            for (String prefix : prefixes) {
                // 从本地文件系统获取文件
                String localFolderPath = bucketPath + "/" + prefix;
                File localFolder = new File(localFolderPath);
                if (!localFolder.exists() || !localFolder.isDirectory()) {
                    throw new FileNotFoundException("Local folder not found: " + localFolderPath);
                }

                // 压缩文件夹
                zipFolder(localFolder, prefix, zos);
            }
        }
    }

    private void zipFolder(File folder, String parentFolder, ZipOutputStream zos) throws IOException {
        for (File file : folder.listFiles()) {
            if (file.isDirectory()) {
                zipFolder(file, parentFolder + "/" + file.getName(), zos);
                continue;
            }
            zos.putNextEntry(new ZipEntry(parentFolder + "/" + file.getName()));
            try (FileInputStream fis = new FileInputStream(file)) {
                byte[] buffer = new byte[1024];
                int length;
                while ((length = fis.read(buffer)) >= 0) {
                    zos.write(buffer, 0, length);
                }
            }
            zos.closeEntry();
        }
    }

    public static void main(String[] args) {
        try {
            String bucketPath = "/data/software/minio-data/cloud-bucket";
            List<String> prefixes = List.of(
                    "c88e9f12-9fab-4aca-8fc4-b02d0b0ce5f2/DJI_202407151726_001_c88e9f12-9fab-4aca-8fc4-b02d0b0ce5f2/"
            );

            MinioFileDownloader downloader = new MinioFileDownloader(bucketPath);

            // 下载并压缩文件到本地目录
            String localSaveDir = "/path/to/local/save/directory"; // 修改为你想保存的本地目录
            downloader.downloadAndZipFolders(prefixes, localSaveDir);

            System.out.println("压缩文件已保存到：" + localSaveDir);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}