import urllib.request
import os
import time
from urllib.parse import quote
from html.parser import HTMLParser

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 _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: str, force_update=False) -> list:
        """优先读取缓存，不存在时爬取"""
        if not force_update:
            cached = self._load_from_cache(query)
            if cached:
                print("📂 从缓存加载数据")
                return cached
        
        print("🌐 正在爬取网络数据...")
        # ...（保持原有的爬取逻辑）...
        data = [{"url": link, "text": self.extract_text(link)} for link in self.parser.links[:5]]
        
        self._save_to_cache(query, data)
        return data
    
    def extract_text(self, url: str) -> str:
        # ...（保持原有的正文提取逻辑）..
        return extracted_text