"""
Centralized runtime settings for the Doof backend.

No external dependencies; reads from environment only so it can be imported
anywhere (including tests) without side effects.
"""

from __future__ import annotations

import os
from dataclasses import dataclass
from typing import Optional


@dataclass(frozen=True)
class Settings:
    # Database
    database_path: str = os.environ.get("DOOF_DB", "./data/doof.sqlite")

    # Environment flags
    prod: bool = os.environ.get("DOOF_PROD", "false").lower() in {"1", "true", "yes"}

    # Frontend dev server for reverse proxy in non-prod
    frontend_dev_url: str = os.environ.get("FRONTEND_DEV_URL", "http://localhost:8000/")

    # JWT settings
    jwt_issuer: str = os.environ.get("DOOF_JWT_ISSUER", "doof-backend")
    jwt_audience: str = os.environ.get("DOOF_JWT_AUDIENCE", "doof-web")
    access_ttl_seconds: int = int(os.environ.get("DOOF_JWT_ACCESS_TTL", "900"))  # 15 minutes
    refresh_ttl_seconds: int = int(os.environ.get("DOOF_JWT_REFRESH_TTL", "2592000"))  # 30 days
    access_secret_b64: Optional[str] = os.environ.get("DOOF_JWT_ACCESS_SECRET_B64")
    refresh_secret_b64: Optional[str] = os.environ.get("DOOF_JWT_REFRESH_SECRET_B64")


# A module-level singleton for convenience imports
settings = Settings()