import os
import re
import json
from typing import List, Dict

from config.config import data_dir
from util.logger import get_logger

logger = get_logger()

"""
递归获取 data_dir 下的所有 .txt 文件列表
"""
def get_file_list() -> List[str]:
    txt_files = []
    txt_exist_flag = False
    for root, dirs, files in os.walk(data_dir):
        for file in files:
            if file.endswith('.txt'):
                txt_exist_flag = True
                txt_files.append(os.path.join(root, file))

    if not txt_exist_flag:
        logger.warning(f'No txt text found in {data_dir}, please check!')
    return txt_files

"""
获取 txt 文本的所有内容，按句子返回 List
file_path: txt 文本路径
window_size: 滑窗大小，单位为句子数
overlap_size: 重叠大小，单位为句子数
"""
def get_txt_content(
    file_path: str,
    window_size: int = 6,
    overlap_size: int = 2
) -> List[str]:
    with open(file_path, 'r', encoding='utf-8') as f:
        content = f.read().strip()

    # 简单实现：按句号、感叹号、问号分割，并去除句内空白符
    sentences = re.split(r'(?<=[。！？])\s+', content)
    sentences = [s.replace(' ', '').replace('\t', '') for s in sentences]

    # 滑窗
    res = []
    sentences_amount = len(sentences)
    start_index, end_index = 0, sentences_amount - window_size
    ## check length
    if window_size < overlap_size:
        logger.error("window_size must be greater than or equal to overlap_size")
        return None
    if window_size >= sentences_amount:
        logger.warning("window_size exceeds the amount of sentences, and the complete text content will be returned")
        return ['\n'.join(sentences)]
    
    for i in range(start_index, end_index + 1, overlap_size):
        res.append('\n'.join(sentences[i : i + window_size]))
    return res


"""
提取返回的 QA 对
"""
def capture_qa(content: str) -> List[Dict]:
    # 只捕获第一个 json 块
    match = re.search(r'```json(.*?)```', content, re.DOTALL)

    if match:
        parsed_data = None
        block = match.group(1)
        try:
            parsed_data = json.loads(block)
        except:
            logger.warning('Unable to parse JSON properly.')
        finally:
            return parsed_data
    else:
        logger.warning("No JSON block found.")
        return None