import json
import logging
from functools import lru_cache
from pathlib import Path

from django.http import HttpRequest, JsonResponse
from django.utils.translation import get_language_from_request

LOGGER = logging.getLogger(__name__)


@lru_cache(maxsize=1)
def lobby_i18n_catalog() -> dict:
    catalog_path = Path(__file__).resolve().parents[1] / "shared" / "i18n" / "lobby.json"
    with catalog_path.open(encoding="utf-8") as handle:
        return json.load(handle)


@lru_cache(maxsize=1)
def i18n_locale_config() -> tuple[str, tuple[str, ...]]:
    locales = lobby_i18n_catalog().get("locales", {})
    default_locale = str(locales.get("default", "en")).strip().lower() or "en"
    supported_locales = tuple(
        locale.strip().lower() for locale in locales.get("supported", ["en", "da"]) if str(locale).strip()
    ) or ("en", "da")
    return default_locale, supported_locales


def lobby_i18n_errors() -> dict:
    return lobby_i18n_catalog().get("backend", {}).get("error_codes", {})


def lobby_i18n_error_messages() -> dict:
    return lobby_i18n_catalog().get("backend", {}).get("errors", {})


def resolve_locale(request: HttpRequest) -> str:
    default_locale, supported_locales = i18n_locale_config()
    requested = (get_language_from_request(request) or "").split("-", 1)[0].lower()
    if requested in supported_locales:
        return requested
    return default_locale


def resolve_error_message(*, key: str, locale: str) -> str:
    default_locale, _supported_locales = i18n_locale_config()
    translations = lobby_i18n_error_messages().get(key)
    if not isinstance(translations, dict):
        LOGGER.warning("i18n key missing in shared catalog", extra={"key": key, "locale": locale})
        return key

    if locale in translations and translations[locale]:
        return translations[locale]
    if default_locale in translations and translations[default_locale]:
        return translations[default_locale]

    LOGGER.warning("i18n translation missing for key", extra={"key": key, "locale": locale})
    return key


def api_error(request: HttpRequest, *, key: str, status: int) -> JsonResponse:
    locale = resolve_locale(request)
    return JsonResponse(
        {
            "error": resolve_error_message(key=key, locale=locale),
            "error_code": key,
            "locale": locale,
        },
        status=status,
    )