"""运输计划相关日期时间解析：前端 date-picker 仅传 YYYY-MM-DD。"""
from __future__ import annotations

from datetime import date, datetime, time
from typing import Annotated, Optional

from pydantic import BeforeValidator


def parse_optional_plan_datetime(value: object) -> Optional[datetime]:
    if value is None:
        return None
    if isinstance(value, datetime):
        return value
    if isinstance(value, date):
        return datetime.combine(value, time.min)
    if isinstance(value, str):
        text = value.strip()
        if not text:
            return None
        if len(text) == 10 and text[4] == "-" and text[7] == "-":
            return datetime.strptime(text, "%Y-%m-%d")
        return datetime.fromisoformat(text.replace("Z", "+00:00"))
    raise ValueError("invalid datetime")


OptionalPlanDateTime = Annotated[Optional[datetime], BeforeValidator(parse_optional_plan_datetime)]