"""
Client for the stack's central Settings service.

NewBook credentials are managed once in the Settings app (LXC 116) and
fetched live by every app — the same pattern as cashup / room-planner /
maintenance (see their lib/newbook.js). Falls back to None if the service
is unreachable so callers can fall back to app-local config.
"""
import logging
import os
import time
from typing import Optional

import httpx

logger = logging.getLogger(__name__)

SETTINGS_URL = os.getenv("SETTINGS_URL", "")
SETTINGS_SECRET = os.getenv("SETTINGS_SECRET", "")

_CACHE_TTL = 60  # seconds — credentials change rarely; avoid hammering the service
_cache: dict = {}


async def get_integration(name: str) -> Optional[dict]:
    """
    Fetch integration config (e.g. 'newbook') from the central Settings
    service. Returns the config dict, or None if unavailable/unconfigured.
    """
    if not SETTINGS_URL or not SETTINGS_SECRET:
        return None

    cached = _cache.get(name)
    if cached and (time.monotonic() - cached[0]) < _CACHE_TTL:
        return cached[1]

    url = f"{SETTINGS_URL}/settings/api/internal/integration/{name}"
    try:
        async with httpx.AsyncClient(timeout=5.0) as client:
            resp = await client.get(
                url, headers={"Authorization": f"Bearer {SETTINGS_SECRET}"}
            )
            resp.raise_for_status()
            data = resp.json()
            _cache[name] = (time.monotonic(), data)
            return data
    except Exception as e:
        logger.warning(f"Central settings fetch failed for '{name}': {e}")
        return None


def _extract_newbook(s: Optional[dict]) -> Optional[dict]:
    if not s:
        return None
    creds = {
        "api_key": s.get("api_key") or "",
        "username": s.get("username") or "",
        "password": s.get("password") or "",
        "region": s.get("region") or "eu",
    }
    # Only usable if the essential fields are present
    if not (creds["api_key"] and creds["username"] and creds["password"]):
        return None
    return creds


async def get_newbook_credentials() -> Optional[dict]:
    """
    Returns {'api_key', 'username', 'password', 'region'} from central
    settings, or None if not available (caller should fall back).
    """
    return _extract_newbook(await get_integration("newbook"))


def get_integration_sync(name: str) -> Optional[dict]:
    """Blocking variant of get_integration for sync job contexts."""
    if not SETTINGS_URL or not SETTINGS_SECRET:
        return None

    cached = _cache.get(name)
    if cached and (time.monotonic() - cached[0]) < _CACHE_TTL:
        return cached[1]

    url = f"{SETTINGS_URL}/settings/api/internal/integration/{name}"
    try:
        resp = httpx.get(
            url, headers={"Authorization": f"Bearer {SETTINGS_SECRET}"}, timeout=5.0
        )
        resp.raise_for_status()
        data = resp.json()
        _cache[name] = (time.monotonic(), data)
        return data
    except Exception as e:
        logger.warning(f"Central settings fetch failed for '{name}': {e}")
        return None


def get_newbook_credentials_sync() -> Optional[dict]:
    """Blocking variant of get_newbook_credentials for sync job contexts."""
    return _extract_newbook(get_integration_sync("newbook"))