src/main/java/com/pt/service/ResourceService.java

package com.pt.service;

import com.pt.entity.Download;
import com.pt.entity.Resource;
import com.pt.entity.TorrentMeta;
import com.pt.repository.DownloadRepository;
import com.pt.repository.ResourceRepository;
import com.pt.repository.TorrentMetaRepository;
import com.pt.utils.BencodeUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.time.LocalDateTime;
import java.util.List;
import java.util.Map;

@Service
public class ResourceService {

    @Autowired
    private ResourceRepository resourceRepository;

    @Autowired
    private DownloadRepository downloadRepository;

    @Autowired
    private TorrentService torrentService;

    @Autowired
    private TorrentMetaRepository torrentMetaRepository;

    public List<Resource> getAllResources() {
        return resourceRepository.findAll();
    }

    public List<Resource> getResourcesByAuthor(String username) {
        return resourceRepository.findByAuthor(username);
    }

    // 发布资源时，将种子文件二进制数据保存到数据库
    public void publishResource(String name, String description, String author, double size) throws Exception {
        // 保存资源信息到数据库，包括种子文件的二进制数据
        Resource resource = new Resource();
        resource.setName(name);
        resource.setDescription(description);
        resource.setAuthor(author);
        resource.setSize(size);
        resource.setPublishTime(LocalDateTime.now());

        // 生成种子数据 byte[]
        byte[] torrentData = torrentService.generateTorrentBytes("uploads/" + name);
        resource.setTorrentData(torrentData);

        resourceRepository.save(resource);
    }

    // 获取资源时，返回BLOB字段内容作为torrent文件
    public byte[] getTorrentFileByResource(Resource resource, String username) {
        if(resource == null || resource.getTorrentData() == null) return null;

        // 记录下载日志
        Download download = new Download();
        download.setResourceId(String.valueOf(resource.getResourceId()));
        download.setDownloader(username);
        download.setDownloadTime(LocalDateTime.now());
        downloadRepository.save(download);

        return resource.getTorrentData();
    }

    public Resource getResourceById(int id) {
        return resourceRepository.findById(id).orElse(null);
    }

    public void deleteResource(int id) {
        Resource resource = getResourceById(id);
        if (resource != null) {
            // 删除数据库资源记录
            resourceRepository.deleteById(id);

            // 删除对应的 TorrentMeta 元信息
            TorrentMeta meta = torrentMetaRepository.findByFilename(resource.getName());
            if (meta != null) {
                torrentMetaRepository.delete(meta);
            }

        }
    }
    public List<Resource> searchByQuery(String query) {
        return resourceRepository.findByNameContainingIgnoreCase(query);
    }

}