import urllib.request
import os
import time
from urllib.parse import quote
from html.parser import HTMLParser
import requests # type: ignore
from bs4 import BeautifulSoup # type: ignore
from urllib.parse import quote_plus

class PureHTMLParser(HTMLParser):
    
    # ...（保持之前的HTML解析器代码不变）...

 class PureCrawler:
    def __init__(self, cache_dir="cache"):
        self.user_agent = "Mozilla/5.0"
        self.parser = PureHTMLParser()
        self.cache_dir = cache_dir
        os.makedirs(cache_dir, exist_ok=True)
    
    def _is_cache_valid(self, cache_file):
        """检查缓存是否有效"""
        if not os.path.exists(cache_file):
            return False
            
        file_time = os.path.getmtime(cache_file)
        return (time.time() - file_time) < self.cache_expiry

    def _get_cache_path(self, query: str) -> str:
        """生成缓存文件名"""
        safe_query = "".join(c if c.isalnum() else "_" for c in query)
        return f"{self.cache_dir}/{safe_query}.txt"
    
    def _save_to_cache(self, query: str, data: list):
        """保存搜索结果到缓存"""
        with open(self._get_cache_path(query), "w", encoding="utf-8") as f:
            for item in data:
                f.write(f"URL: {item['url']}\n")
                f.write(f"Text: {item['text']}\n")
                f.write("="*50 + "\n")
    
    def _load_from_cache(self, query: str) -> list:
        """从缓存加载数据"""
        cache_file = self._get_cache_path(query)
        if not os.path.exists(cache_file):
            return None
        
        with open(cache_file, "r", encoding="utf-8") as f:
            content = f.read()
        
        # 解析缓存文件
        items = []
        for block in content.split("="*50):
            if not block.strip():
                continue
            url = text = ""
            for line in block.split("\n"):
                if line.startswith("URL: "):
                    url = line[5:]
                elif line.startswith("Text: "):
                    text = line[6:]
            if url:
                items.append({"url": url, "text": text})
        return items
    
    def fetch(self, query, force_update=False):

        cache_file = os.path.join(self.cache_dir, f"{quote_plus(query)}.json")
        
        # 检查缓存是否有效
        if not force_update and self._is_cache_valid(cache_file):
            return self._load_from_cache(cache_file)
            
        try:
            # 实际抓取逻辑 - 以百度搜索为例
            search_url = f"https://www.baidu.com/s?wd={quote_plus(query)}"
            response = requests.get(search_url, headers=self.headers, timeout=10)
            response.raise_for_status()
            
            # 解析网页内容
            soup = BeautifulSoup(response.text, 'html.parser')
            results = [(query)]
            
            # 提取搜索结果 - 根据实际网站结构调整
            for item in soup.select('.result.c-container'):
                title = item.select_one('h3').get_text(strip=True)
                link = item.find('a')['href']
                abstract = item.select_one('.c-abstract').get_text(strip=True) if item.select_one('.c-abstract') else ""
                results.append({
                    'title': title,
                    'url': link,
                    'abstract': abstract
                })
            
            data = {
                'query': query,
                'results': results,
                'timestamp': int(time.time()),
                'sources': [search_url]
            }
            
            # 保存到缓存
            self._save_to_cache(cache_file, data)
            return data
            
        except Exception as e:
            # 如果抓取失败但缓存存在，使用缓存
            if os.path.exists(cache_file):
                print(f"抓取失败，使用缓存数据: {str(e)}")
                return self._load_from_cache(cache_file)
            raise RuntimeError(f"抓取失败且无缓存可用: {str(e)}")