import os
import time
import logging
import psycopg2
from urllib.parse import unquote
from find_text_in_pdf import PDFTextFinder

# 配置日志
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(levelname)s - %(message)s'
)
logger = logging.getLogger(__name__)

class TextSplitter:
    @staticmethod
    def split_text(text):
        """将文本分割成句子"""
        # 使用常见的标点符号作为分隔符
        delimiters = ['.', '!', '?', '。', '！', '？', '\n', ';', '。', '；']
        sentences = [text]
        for delimiter in delimiters:
            new_sentences = []
            for sentence in sentences:
                new_sentences.extend(sentence.split(delimiter))
            sentences = [s.strip() for s in new_sentences if s.strip()]
        return sentences

class PDFPageUpdater:
    def __init__(self, db_params, books_dir):
        """初始化更新器
        
        Args:
            db_params: 数据库连接参数字典
            books_dir: PDF文件所在目录
        """
        self.db_params = db_params
        self.books_dir = books_dir
        self._page_cache = {}
    
    def connect_db(self):
        """连接到数据库"""
        return psycopg2.connect(**self.db_params)
    
    def get_records_without_page(self):
        """获取没有页码的记录"""
        query = """
        SELECT id, content, referrence, title 
        FROM public.trunks 
        WHERE page_no IS NULL 
        AND referrence LIKE '%/books/%' 
        AND referrence LIKE '%.pdf'
        AND type ='trunk'
        AND file_path LIKE '%《内科学 第10版》%'
        """
        
        with self.connect_db() as conn:
            with conn.cursor() as cur:
                cur.execute(query)
                return cur.fetchall()
    
    def update_page_number(self, record_id, page_no):
        """更新记录的页码
        
        Args:
            record_id: 记录ID
            page_no: 页码
        """
        query = """
        UPDATE public.trunks 
        SET page_no = %s 
        WHERE id = %s
        """
        
        with self.connect_db() as conn:
            with conn.cursor() as cur:
                cur.execute(query, (page_no, record_id))
                conn.commit()
    
    def find_page_number(self, pdf_path, content, title):
        """在PDF中查找内容对应的页码
        
        Args:
            pdf_path: PDF文件路径
            content: 要查找的内容
            title: 文档标题（用于缓存）
            
        Returns:
            int or None: 找到的页码，未找到则返回None
        """
        # 使用文件名和标题作为缓存键
        file_name = os.path.basename(pdf_path)
        cache_key = f"{file_name}:{title}"
        
        # 检查缓存
        if cache_key in self._page_cache:
            return self._page_cache[cache_key]
        
        # 首先尝试完整内容匹配
        start_time = time.time()
        pages = PDFTextFinder(pdf_path).find_text(content.replace(' ', ''))
        search_time = time.time() - start_time
        logger.info(f"PDF页码搜索耗时: {search_time * 1000:.2f}ms (文件: {file_name}, 内容: {content[:50]}...)")
        
        if pages and len(pages) > 0:
            page_no = pages[0]
            self._page_cache[cache_key] = page_no
            return page_no
        
        # 如果完整匹配失败，尝试按句子搜索
        sentences = TextSplitter.split_text(content)
        tried_sentences = 0
        page_counts = {}
        
        for sentence in sentences:
            if len(sentence) < 10:  # 跳过过短的句子
                continue
            if tried_sentences >= 7:  # 最多尝试3句
                break
            
            pages = PDFTextFinder(pdf_path).find_text(sentence.replace(' ', ''))
            if pages and len(pages) > 0:
                page_no = pages[0]
                page_counts[page_no] = page_counts.get(page_no, 0) + 1
                
                # 如果某个页码出现两次或相邻页码各出现一次，使用该页码
                for p in page_counts:
                    if page_counts[p] >= 2 or (page_counts.get(p-1, 0) + page_counts.get(p+1, 0) > 0):
                        self._page_cache[cache_key] = p
                        return p
            
            tried_sentences += 1
        
        return None
    
    def process_records(self):
        """处理所有没有页码的记录"""
        records = self.get_records_without_page()
        total = len(records)
        logger.info(f"找到 {total} 条需要更新页码的记录")
        
        for i, (record_id, content, referrence, title) in enumerate(records, 1):
            try:
                # 从referrence构建PDF路径
                file_name = unquote(referrence.split("/books/")[-1])
                pdf_path = os.path.join(self.books_dir, file_name)
                
                if not os.path.exists(pdf_path):
                    logger.warning(f"PDF文件不存在: {pdf_path}")
                    continue
                
                # 查找页码
                page_no = self.find_page_number(pdf_path, content, title)
                
                if page_no:
                    # 更新数据库
                    self.update_page_number(record_id, page_no)
                    logger.info(f"进度: [{i}/{total}] 已更新记录 {record_id} 的页码为 {page_no}")
                else:
                    logger.warning(f"进度: [{i}/{total}] 未找到记录 {record_id} 的页码")
                
            except Exception as e:
                logger.error(f"处理记录 {record_id} 时出错: {str(e)}")
                continue

def main():
    # 数据库连接参数
    db_params = {
        'dbname': 'medkg',
        'user': 'knowledge',
        'password': 'qwer1234.',  # 请替换为实际密码
        'host': '173.18.12.203',
        'port': '5432'
    }
    
    # PDF文件目录路径
    books_dir = 'C:\\Users\\17664\\Desktop'
    
    try:
        updater = PDFPageUpdater(db_params, books_dir)
        updater.process_records()
        logger.info("页码更新完成")
    except Exception as e:
        logger.error(f"程序执行出错: {str(e)}")

if __name__ == "__main__":
    main()