Java/W9/command/HistoryCommand.java

package com.example.datacollect.command;

import com.example.datacollect.model.Article;
import com.example.datacollect.model.DataService;
import com.example.datacollect.service.HistoryService;
import com.example.datacollect.view.ConsoleView;
import java.util.List;

public class HistoryCommand implements Command {
    private final ConsoleView view;
    private final HistoryService historyService;

    public HistoryCommand(ConsoleView view, HistoryService historyService) {
        this.view = view;
        this.historyService = historyService;
    }

    @Override
    public String getName() {
        return "history";
    }

    @Override
    public void execute(String[] args, DataService dataService) {
        // 参数解析：history <count> 或 history <index>
        if (args.length == 1) {
            // 显示全部
            List<String> allHistory = historyService.getHistory();
            view.displayHistory(allHistory);
            return;
        }

        String param = args[1].toLowerCase();
        if (param.equals("clear")) {
            historyService.clear();
            view.printSuccess("历史命令已清空。");
            return;
        }

        try {
            int limit = Integer.parseInt(param);
            List<String> allHistory = historyService.getHistory();

            if (limit <= 0) {
                view.printError("数量必须大于 0");
                return;
            }

            // 显示最近 N 条
            int start = Math.max(0, allHistory.size() - limit);
            List<String> recentHistory = allHistory.subList(start, allHistory.size());

            view.printInfo("最近 " + limit + " 条命令:");
            System.out.println("--------------------------------------------------");
            for (int i = 0; i < recentHistory.size(); i++) {
                System.out.println((recentHistory.size() - i) + ". " + recentHistory.get(i));
            }
            System.out.println("--------------------------------------------------");

        } catch (NumberFormatException e) {
            view.printError("参数必须是数字或 'clear'");
        }
    }
}