"""Shared translation logging context helpers."""

from __future__ import annotations

import contextvars
import logging
import uuid
from typing import Optional


_translation_request_id_var: contextvars.ContextVar[Optional[str]] = contextvars.ContextVar(
    "translation_request_id",
    default=None,
)


def current_translation_request_id() -> str:
    return _translation_request_id_var.get() or "-1"


def bind_translation_request_id(request_id: Optional[str] = None) -> tuple[str, contextvars.Token]:
    raw_value = str(request_id or "").strip()
    normalized = raw_value[:32] if raw_value else str(uuid.uuid4())[:8]
    return normalized, _translation_request_id_var.set(normalized)


def reset_translation_request_id(token: contextvars.Token) -> None:
    _translation_request_id_var.reset(token)


class TranslationRequestFilter(logging.Filter):
    """Inject a request id into translator logs when one is available."""

    def filter(self, record: logging.LogRecord) -> bool:
        if not hasattr(record, "reqid"):
            record.reqid = current_translation_request_id()
        return True