"""Application configuration loaded from environment variables."""
from __future__ import annotations

import os
import secrets
from pathlib import Path

# Where persistent data (SQLite DB) lives. Mounted as a volume in Docker.
DATA_DIR = Path(os.getenv("DATA_DIR", "./data")).resolve()
DATA_DIR.mkdir(parents=True, exist_ok=True)

DATABASE_URL = os.getenv("DATABASE_URL", f"sqlite:///{DATA_DIR / 'app.db'}")

# Secret used to sign session cookies. Generate a stable one if not provided,
# persisting it to disk so sessions survive restarts.
_SECRET_FILE = DATA_DIR / "secret.key"


def _load_secret() -> str:
    env = os.getenv("SECRET_KEY")
    if env:
        return env
    if _SECRET_FILE.exists():
        return _SECRET_FILE.read_text().strip()
    value = secrets.token_hex(32)
    _SECRET_FILE.write_text(value)
    return value


SECRET_KEY = _load_secret()

# Defaults used the first time the app starts (before any settings are saved).
DEFAULT_NTFY_SERVER = os.getenv("DEFAULT_NTFY_SERVER", "https://ntfy.sh")
DEFAULT_CHECK_INTERVAL = int(os.getenv("DEFAULT_CHECK_INTERVAL", "5"))  # minutes

# Bootstrap admin credentials (only applied when the settings row is created).
ADMIN_USERNAME = os.getenv("ADMIN_USERNAME", "admin")
ADMIN_PASSWORD = os.getenv("ADMIN_PASSWORD", "admin")