"""Tests for the application configuration loader."""

import os
from unittest.mock import patch

from app.config import Settings, get_settings


class TestSettings:
    """Tests for the Settings configuration class."""

    def test_settings_loads_defaults(self) -> None:
        """Settings should have sensible defaults for all fields."""
        # Remove DATABASE_URL so we test the actual default
        env_clean = {k: v for k, v in os.environ.items() if k != "DATABASE_URL"}
        with patch.dict(os.environ, env_clean, clear=True):
            settings = Settings()
            assert settings.app_env == "development"
            assert settings.app_host == "0.0.0.0"
            assert settings.app_port == 8000
            assert settings.database_url == "sqlite:///data/sneakyswole.db"

    def test_get_settings_returns_singleton(self) -> None:
        """get_settings should return the same instance on repeated calls."""
        s1 = get_settings()
        s2 = get_settings()
        assert s1 is s2