"""爬虫工具函数"""

import logging
from datetime import datetime, timedelta
from pathlib import Path

import yaml

logger = logging.getLogger(__name__)

# 默认日切分小时（凌晨）
DEFAULT_CUTOFF_HOUR = 6


def _load_cutoff_hour() -> int:
    """从 system.yaml 读取日切分小时"""
    config_path = Path("configs/system.yaml")
    if config_path.exists():
        try:
            with open(config_path, encoding="utf-8") as f:
                raw = yaml.safe_load(f)
            return int(raw.get("schedule", {}).get("day_cutoff_hour", DEFAULT_CUTOFF_HOUR))
        except Exception:
            pass
    return DEFAULT_CUTOFF_HOUR


def get_news_day(now: datetime | None = None) -> str:
    """获取当前新闻日（YYYYMMDD）

    规则：当天 06:00 到次日 05:59 属于同一个新闻日。
    例如 2026-06-19 04:00 → "20260618"，07:00 → "20260619"

    Args:
        now: 参考时间，默认当前时间

    Returns:
        新闻日字符串 YYYYMMDD
    """
    if now is None:
        now = datetime.now()

    cutoff = _load_cutoff_hour()

    if now.hour < cutoff:
        # 凌晨 0:00 - 5:59，属于前一天
        news_date = now - timedelta(days=1)
    else:
        news_date = now

    return news_date.strftime("%Y%m%d")