# -*- coding: utf-8 -*-
"""
附件下载和解析模块
支持PDF和Word文档
"""
import os
import re
import requests
import pdfplumber
from docx import Document
from typing import Optional, Dict, List


class AttachmentHandler:
    """附件处理器"""
    
    def __init__(self, download_dir: str = "attachments"):
        self.download_dir = download_dir
        os.makedirs(download_dir, exist_ok=True)
        
    def download(self, url: str, filename: str = None) -> Optional[str]:
        """
        下载附件
        
        Args:
            url: 附件URL
            filename: 保存的文件名（可选）
            
        Returns:
            保存的文件路径，失败返回None
        """
        try:
            # 处理URL
            if not url.startswith('http'):
                return None
            
            # 生成文件名
            if not filename:
                filename = url.split('/')[-1]
                # 清理文件名
                filename = re.sub(r'[<>:"/\\|?*]', '_', filename)
            
            filepath = os.path.join(self.download_dir, filename)
            
            # 下载文件
            headers = {
                'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) Chrome/120.0.0.0'
            }
            response = requests.get(url, headers=headers, timeout=60, stream=True)
            response.raise_for_status()
            
            with open(filepath, 'wb') as f:
                for chunk in response.iter_content(chunk_size=8192):
                    f.write(chunk)
                    
            print(f"  下载成功: {filename}")
            return filepath
            
        except Exception as e:
            print(f"  下载失败: {e}")
            return None
    
    def extract_pdf_text(self, filepath: str) -> str:
        """
        提取PDF文本内容
        
        Args:
            filepath: PDF文件路径
            
        Returns:
            提取的文本内容
        """
        text = ""
        try:
            with pdfplumber.open(filepath) as pdf:
                for page in pdf.pages:
                    page_text = page.extract_text()
                    if page_text:
                        text += page_text + "\n\n"
        except Exception as e:
            print(f"  PDF解析失败: {e}")
        return text.strip()
    
    def extract_docx_text(self, filepath: str) -> str:
        """
        提取Word文档文本内容
        
        Args:
            filepath: Word文件路径
            
        Returns:
            提取的文本内容
        """
        text = ""
        try:
            doc = Document(filepath)
            for para in doc.paragraphs:
                text += para.text + "\n"
            
            # 提取表格内容
            for table in doc.tables:
                for row in table.rows:
                    row_text = " | ".join([cell.text.strip() for cell in row.cells])
                    text += row_text + "\n"
        except Exception as e:
            print(f"  Word解析失败: {e}")
        return text.strip()
    
    def extract_text(self, filepath: str) -> str:
        """
        根据文件类型提取文本
        
        Args:
            filepath: 文件路径
            
        Returns:
            提取的文本内容
        """
        if not filepath or not os.path.exists(filepath):
            return ""
        
        ext = os.path.splitext(filepath)[1].lower()
        
        if ext == '.pdf':
            return self.extract_pdf_text(filepath)
        elif ext in ['.doc', '.docx']:
            return self.extract_docx_text(filepath)
        else:
            return ""
    
    def download_and_extract(self, url: str, filename: str = None) -> Dict:
        """
        下载并提取附件内容
        
        Args:
            url: 附件URL
            filename: 保存的文件名
            
        Returns:
            包含文件路径和文本内容的字典
        """
        result = {
            "url": url,
            "filepath": None,
            "text": "",
            "success": False
        }
        
        filepath = self.download(url, filename)
        if filepath:
            result["filepath"] = filepath
            result["text"] = self.extract_text(filepath)
            result["success"] = True
            
        return result


def find_attachments(page) -> List[Dict]:
    """
    从页面中查找附件链接
    
    Args:
        page: DrissionPage页面对象
        
    Returns:
        附件信息列表 [{"name": "文件名", "url": "下载链接"}, ...]
    """
    attachments = []
    
    # 查找PDF链接
    pdf_links = page.eles('css:a[href*=".pdf"]')
    for link in pdf_links:
        href = link.attr('href') or ''
        name = link.text.strip() or href.split('/')[-1]
        if href:
            # 处理相对路径
            if href.startswith('/'):
                base_url = '/'.join(page.url.split('/')[:3])
                href = base_url + href
            attachments.append({"name": name, "url": href, "type": "pdf"})
    
    # 查找Word链接
    doc_selectors = ['css:a[href*=".doc"]', 'css:a[href*=".docx"]']
    for sel in doc_selectors:
        doc_links = page.eles(sel)
        for link in doc_links:
            href = link.attr('href') or ''
            name = link.text.strip() or href.split('/')[-1]
            if href:
                if href.startswith('/'):
                    base_url = '/'.join(page.url.split('/')[:3])
                    href = base_url + href
                attachments.append({"name": name, "url": href, "type": "docx"})
    
    return attachments