import hashlib
import os
from utils.logger_handler import logger
from langchain_community.document_loaders import PyPDFLoader, TextLoader
from langchain_community.docstore.document import Document
from typing import *
from utils.path_tool import get_abs_path

def get_file_md5_hex(file_path: str) -> str:
    """获取文件的MD5值"""
    if not os.path.exists(file_path):
        logger.error(f"md5计算: 文件不存在: {file_path}")
        return ""

    if os.path.isdir(file_path):
        logger.error(f"md5计算: 不是文件: {file_path}")
        return ""

    md5_obj = hashlib.md5()

    chunk_size = 4096

    try:
        with open(file_path, 'rb') as f:
            while chunk := f.read(chunk_size):
                md5_obj.update(chunk)
        md5_hex = md5_obj.hexdigest()
        return md5_hex
    except Exception as e:
        logger.error(f"md5计算: 读取文件时出错: {file_path}, 错误信息: {str(e)}")
        return ""


def listdir_with_allowed_type(path, allowed_type):
    """列出目录下所有允许的文件类型"""
    path = get_abs_path(path)
    files = []
    if not os.path.isdir(path):
        logger.error(f"listdir_with_allowed_type: 不是目录: {path}")
        return files

    for file in os.listdir(path):
        if file.endswith(allowed_type):
            files.append(os.path.join(path, file))

    return tuple(files)


def pdf_loader(file_path: str, pwd: str = None) -> List[Document]:
    """加载PDF文件"""
    return PyPDFLoader(file_path, pwd).load()


def txt_loader(file_path: str) -> List[Document]:
    """加载TXT文件"""
    return TextLoader(file_path, encoding='utf-8').load()