java/w10/ListCommand.java

package command;

import model.Paper;
import repository.PaperRepository;
import view.ConsoleView;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

public class ListCommand implements Command {
    private ConsoleView view;

    public ListCommand(ConsoleView view) {
        this.view = view;
    }
    
    @Override
    public void execute(String[] args, PaperRepository repository) {
        try {
            Map<String, List<Paper>> papersByPlatform = repository.loadAllPapersGroupedByPlatform();
            
            if (papersByPlatform.isEmpty()) {
                view.showInfo("暂无论文，请先执行 crawl 命令爬取论文");
            } else {
                int totalCount = 0;
                for (Entry<String, List<Paper>> entry : papersByPlatform.entrySet()) {
                    totalCount += entry.getValue().size();
                }
                
                view.showInfo("当前已获取 " + totalCount + " 篇论文，分布在 " + papersByPlatform.size() + " 个平台:");
                System.out.println();
                
                int globalIndex = 1;
                for (Entry<String, List<Paper>> entry : papersByPlatform.entrySet()) {
                    String platformName = entry.getKey();
                    List<Paper> papers = entry.getValue();
                    
                    System.out.println("【" + platformName + "】 (" + papers.size() + " 篇)");
                    System.out.println("-".repeat(50));
                    
                    for (int i = 0; i < papers.size(); i++) {
                        Paper paper = papers.get(i);
                        view.showPaperInfo(globalIndex, paper);
                        globalIndex++;
                    }
                    
                    System.out.println();
                }
            }
        } catch (Exception e) {
            view.showError("查询失败: " + e.getMessage());
        }
    }
    
    @Override
    public String getDescription() {
        return "查询已获取的论文列表";
    }
    
    @Override
    public String getName() {
        return "list";
    }
}