// src/main/java/com/llm/analysis/BiliBiliSearchCrawler.java
package com.llm.analysis;

import org.jsoup.Connection;
import org.jsoup.Jsoup;
import com.google.gson.JsonArray;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import com.google.gson.JsonSyntaxException;

import java.io.IOException;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class BiliBiliSearchCrawler {

    private static final String SEARCH_API = "https://api.bilibili.com/x/web-interface/search/type";
    
    // 你提供的 B站 SESSDATA Cookie 值 
    private static final String BILI_SESSDATA = "24d61dbf%2C1777714611%2C44d8f%2Ab1CjBJl1nuF4mxKurV7W0WGijaO58BOVfVjSzeBUQynz2TUGqXiUIx2DA1UyDblAjNPF8SVkg3eWg0UWdneW9sWXFfZGE5U2tzcDFZZVhtX1N4dnBaS0tELXAwSEtmUTNGOW00UEUxdmJGMFg5SHJERW5pYlViaU5xLXFjYWp1dmFBNFprck8ydThRIIEC"; 
    
    private static final int ITEMS_PER_PAGE = 20; 
    private static final int TARGET_PAGES = 300 / ITEMS_PER_PAGE; 

    private static final String USER_AGENT = 
            "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/100.0.4896.127 Safari/537.36";
    
    /**
     * 调用 B站搜索 API，获取指定关键词和数量的视频列表。只获取 BVID 和 Title。
     * @param keyword 搜索关键词 (如 "大语言模型")
     * @return 包含 BVID 和 Title 的 Map 列表
     */
    public static List<Map<String, String>> getTopVideos(String keyword) {
        List<Map<String, String>> videoList = new ArrayList<>();
        
        try {
            String encodedKeyword = URLEncoder.encode(keyword, StandardCharsets.UTF_8);

            for (int page = 1; page <= TARGET_PAGES; page++) {
                String url = String.format("%s?search_type=video&keyword=%s&page=%d&pagesize=%d", 
                                            SEARCH_API, encodedKeyword, page, ITEMS_PER_PAGE);

                System.out.println("🤖 正在爬取第 " + page + " 页数据...");

                Connection.Response response = Jsoup.connect(url)
                        .method(Connection.Method.GET)
                        .ignoreContentType(true)
                        .userAgent(USER_AGENT)
                        .cookie("SESSDATA", BILI_SESSDATA) 
                        .execute();
                
                String jsonStr = response.body();
                
                // 诊断代码：只打印第一页，用于调试
                if (page == 1) { 
                    System.out.println("--- 诊断：第 1 页 JSON 响应 (仅截取前 500 字符) ---");
                    System.out.println(jsonStr.substring(0, Math.min(jsonStr.length(), 500)));
                    System.out.println("-----------------------------------------------------");
                }
                
                // 解析 JSON
                JsonObject jsonResponse = JsonParser.parseString(jsonStr).getAsJsonObject();

                if (jsonResponse.get("code").getAsInt() != 0) {
                    System.err.println("API 调用失败，返回消息: " + jsonResponse.get("message").getAsString());
                    break;
                }

                JsonObject data = jsonResponse.getAsJsonObject("data");
                if (data == null) break;
                
                JsonArray results = data.getAsJsonArray("result");
                if (results == null || results.size() == 0) break;
                
                for (int i = 0; i < results.size(); i++) {
                    JsonObject item = results.get(i).getAsJsonObject();
                    
                    if (!item.has("type") || !"video".equals(item.get("type").getAsString())) {
                         continue; 
                    }
                    
                    // 提取 BVID 和 Title
                    String bvid = item.get("bvid") != null ? item.get("bvid").getAsString() : null;
                    String title = item.get("title") != null ? item.get("title").getAsString() : "无标题";
                    
                    // 关键修正：只检查 bvid 是否存在
                    if (bvid != null) {
                        Map<String, String> videoInfo = new HashMap<>(); 
                        videoInfo.put("bvid", bvid);
                        videoInfo.put("title", title.replaceAll("<em[^>]*>|</em>", "")); 
                        videoList.add(videoInfo);
                    }
                    if (videoList.size() >= 300) break;
                }
                
                if (videoList.size() >= 300) break;

                // 礼貌暂停 1 秒
                Thread.sleep(1000); 
            }
        } catch (IOException | InterruptedException | JsonSyntaxException e) {
            System.err.println("爬取过程中发生错误：" + e.getMessage());
        }
        
        System.out.println("🎉 成功获取到 " + videoList.size() + " 条视频的 BVID/Title 数据。");
        return videoList;
    }
}