from datetime import datetime

from django.utils import timezone


def parse_external_china_datetime(value: str | None):
    """外部 records 的时间字符串业务上是中国时间，即使误带 Z 也按本地时间解释。"""
    if not value:
        return None
    text = str(value).strip()
    if not text:
        return None

    normalized = text[:-1] if text.endswith('Z') else text
    try:
        dt = datetime.fromisoformat(normalized)
    except ValueError:
        return None

    tz = timezone.get_current_timezone()
    if timezone.is_aware(dt):
        dt = dt.replace(tzinfo=None)
    return timezone.make_aware(dt, tz)