"""# Summary

App configuration loaded from environment — a Settings dataclass with defaults
plus a singleton settings instance populated from OS environment variables at
import time.

---

The server reads six knobs:

- ``repo_backend`` — ``memory`` (default, zero-dependency demo store) or
  ``mongo`` (persistent, via the shared mongo-ops connection manager).
- ``mongo_uri`` / ``mongo_db`` — connection targets when the Mongo backend is
  selected.
- ``uploads_dir`` — directory that receives uploaded pet photos.
- ``port`` — the port uvicorn binds (kept in sync with the OpenAPI
  ``servers:`` entry and the frontend's ``VITE_API_BASE_URL``).
- ``worker_poll_seconds`` — background worker poll cadence.
- ``worker_max_retries`` — failed-attempt budget before a job is skipped.

``AUTH_SERVER`` is intentionally *not* re-exported here: ``openapi_first``
resolves ``{AUTH_SERVER}`` straight from the process environment when the
application is built, so the env var remains the single source of truth for
the generated bearer-JWT introspection dependency.
"""
import os
from dataclasses import dataclass


@dataclass
class Settings:
    """Runtime configuration settings for the application.

    Attributes:
        debug (bool): Enable debug behavior. Defaults to False.
        repo_backend (str): Persistence flavour, ``memory`` or ``mongo``.
            Defaults to ``memory``.
        mongo_uri (str): MongoDB connection URI. Defaults to mongodb://localhost:27017.
        mongo_db (str): MongoDB database name. Defaults to vet.
        auth_server (str): Auth-server base URL surfaced to operators and
            scripts. Defaults to https://auth.aetoskia.com.
        port (int): Local HTTP port. Defaults to 8020.
        uploads_dir (str): Directory for uploaded pet photos. Defaults to uploads.
        worker_poll_seconds (float): Worker poll cadence in seconds. Defaults to 5.
        worker_max_retries (int): Failed attempts before a job is skipped.
            Defaults to 3.
    """

    debug: bool = False
    repo_backend: str = "memory"
    mongo_uri: str = "mongodb://localhost:27017"
    mongo_db: str = "vet"
    auth_server: str = "https://auth.aetoskia.com"
    port: int = 8020
    uploads_dir: str = "uploads"
    worker_poll_seconds: float = 5.0
    worker_max_retries: int = 3


settings = Settings(
    debug=os.environ.get("DEBUG", "").lower() in ("1", "true", "yes"),
    repo_backend=os.environ.get("REPO_BACKEND", "memory").lower(),
    mongo_uri=os.environ.get("MONGO_URI", "mongodb://localhost:27017"),
    mongo_db=os.environ.get("MONGO_DB", "vet"),
    auth_server=os.environ.get("AUTH_SERVER", "https://auth.aetoskia.com"),
    port=int(os.environ.get("PORT", "8020")),
    uploads_dir=os.environ.get("UPLOADS_DIR", "uploads"),
    worker_poll_seconds=float(os.environ.get("WORKER_POLL_SECONDS", "5")),
    worker_max_retries=int(os.environ.get("WORKER_MAX_RETRIES", "3")),
)