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.service.TrackerService; // 新增导入
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.time.LocalDateTime;
import java.util.HashMap;
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;

    @Autowired
    private TrackerService trackerService; // 新增注入

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

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

    public void publishResource(String name, String title, String description, String author, byte[] torrentBytes, String username) throws Exception {
        // 解析并保存torrent元信息
        TorrentMeta meta = torrentService.parseAndSaveTorrent(torrentBytes);

        // 保存资源信息，并关联torrent信息
        Resource resource = new Resource();
        resource.setName(name);
        resource.setDescription(description);
        resource.setAuthor(author);
        resource.setPublishTime(LocalDateTime.now());
        resource.setTitle(title);

        resource.setTorrentData(torrentBytes);
        // 这里可以保存torrent文件路径，或直接存数据库，依据你的设计
        resourceRepository.save(resource);

        // 在Tracker中注册相关信息
//        Map<String, String[]> params = new HashMap<>();
//        params.put("info_hash", new String[]{meta.getInfoHash()});
//        // 这里peer_id和port可以先使用默认值，实际应用中可以根据需求修改
//        params.put("peer_id", new String[]{username});
//        params.put("port", new String[]{"6881"});
//        trackerService.handleAnnounce(params, ip);
    }

    // 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);
    }

}