"""Shared Pydantic types for datetimes (#42): UTC in the DB, explicit +00:00 on the wire."""
from datetime import datetime
from typing import Annotated, Optional

from pydantic import AfterValidator, PlainSerializer

from src.backend.utils.tempo import as_utc_naive, to_utc_aware

UtcDateTime = Annotated[
    datetime, PlainSerializer(lambda v: to_utc_aware(v).isoformat(), return_type=str)
]

# Input: aware values are converted to UTC naive, naive is taken as UTC.
UtcNaiveInput = Annotated[Optional[datetime], AfterValidator(as_utc_naive)]