import requests
from bs4 import BeautifulSoup
import time

print("=== 简化版B站弹幕爬虫 ===")

# 一些已知的大语言模型相关视频ID
video_list = [
    "BV1pu41137aK",  # 大语言模型科普视频
    "BV1nN4y1Y7o2",  # LLM技术讲解
    "BV1Gu4y1u7rN",  # 大模型应用
    "BV1AN41137Jp",  # 语言模型发展
    "BV1tu4y1u7Jh"   # AI大模型
]

all_danmakus = []

def get_danmaku(bvid):
    """获取视频弹幕"""
    try:
        print(f"正在获取视频 {bvid} 的弹幕...")
        
        # 1. 先获取视频的cid（弹幕ID）
        info_url = f"https://api.bilibili.com/x/web-interface/view?bvid={bvid}"
        headers = {
            'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36',
            'Referer': 'https://www.bilibili.com/'
        }
        
        response = requests.get(info_url, headers=headers, timeout=10)
        data = response.json()
        
        if data['code'] != 0:
            print(f"  无法获取视频信息: {data.get('message')}")
            return []
        
        cid = data['data']['cid']
        print(f"  获取到CID: {cid}")
        
        # 2. 获取弹幕数据
        danmaku_url = f"https://api.bilibili.com/x/v1/dm/list.so?oid={cid}"
        response = requests.get(danmaku_url, headers=headers, timeout=10)
        response.encoding = 'utf-8'
        
        # 解析XML
        soup = BeautifulSoup(response.text, 'xml')
        danmakus = soup.find_all('d')
        
        danmaku_list = []
        for dm in danmakus:
            text = dm.get_text().strip()
            if text and len(text) > 0:
                danmaku_list.append(text)
        
        print(f"  成功获取 {len(danmaku_list)} 条弹幕")
        return danmaku_list
        
    except Exception as e:
        print(f"  获取弹幕失败: {e}")
        return []

# 主程序
for i, bvid in enumerate(video_list):
    print(f"\n处理第 {i+1}/{len(video_list)} 个视频: {bvid}")
    danmakus = get_danmaku(bvid)
    all_danmakus.extend(danmakus)
    
    # 每次获取后都保存
    with open('bilibili_danmaku.txt', 'w', encoding='utf-8') as f:
        for dm in all_danmakus:
            f.write(dm + '\n')
    
    # 延时避免请求过快
    time.sleep(1)

print(f"\n=== 完成！共获取 {len(all_danmakus)} 条弹幕 ===")

# 显示统计信息
if all_danmakus:
    print("\n弹幕示例:")
    for i in range(min(10, len(all_danmakus))):
        print(f"{i+1}. {all_danmakus[i]}")
    
    # 保存统计信息
    with open('danmaku_stats.txt', 'w', encoding='utf-8') as f:
        f.write(f"总弹幕数: {len(all_danmakus)}\n")
        f.write("前10条弹幕:\n")
        for i, dm in enumerate(all_danmakus[:10]):
            f.write(f"{i+1}. {dm}\n")
    
    print(f"\n统计信息已保存到: danmaku_stats.txt")
else:
    print("没有获取到弹幕数据")

print(f"弹幕数据已保存到: bilibili_danmaku.txt")