import pytest
from unittest.mock import MagicMock, patch
from fastapi.testclient import TestClient
from main import app
from src.api.auth import get_db, FitbitCredentials
from src.models import Configuration, APIToken

@pytest.fixture
def mock_db_session():
    return MagicMock()

@pytest.fixture
def client(mock_db_session):
    def override_get_db():
        try:
            yield mock_db_session
        finally:
            pass
    app.dependency_overrides[get_db] = override_get_db
    yield TestClient(app)
    app.dependency_overrides.clear()

def test_save_fitbit_credentials(client, mock_db_session):
    """Test saving Fitbit credentials and generating auth URL."""
    payload = {
        "client_id": "test_client_id",
        "client_secret": "test_client_secret",
        "redirect_uri": "http://localhost/callback"
    }

    # Mock DB query for existing config
    mock_db_session.query.return_value.first.return_value = None 
    # Mock Config creation is handled by code logic (checks if exists, else creates)
    
    with patch("src.api.auth.FitbitClient") as MockFitbitClient:
        instance = MockFitbitClient.return_value
        instance.get_authorization_url.return_value = "https://www.fitbit.com/oauth2/authorize?client_id=test_client_id"
        
        response = client.post("/api/setup/fitbit", json=payload)
        
        assert response.status_code == 200
        data = response.json()
        assert "auth_url" in data
        assert "test_client_id" in data["auth_url"]
        
        # Verify DB interactions
        # Should add new config
        assert mock_db_session.add.called
        assert mock_db_session.commit.called

def test_fitbit_callback_success(client, mock_db_session):
    """Test Fitbit OAuth callback success."""
    # Setup initial config in mock DB
    mock_config = MagicMock(spec=Configuration)
    mock_config.fitbit_client_id = "cid"
    mock_config.fitbit_client_secret = "csec"
    mock_config.fitbit_redirect_uri = "uri"
    
    mock_db_session.query.return_value.first.return_value = mock_config
    
    # Mock Token query (return None so it creates new)
    # query(Configuration).first() -> config
    # query(APIToken).filter_by().first() -> None (to trigger creation)
    
    def query_side_effect(model):
        m = MagicMock()
        if model == Configuration:
            m.first.return_value = mock_config
        elif model == APIToken:
            m.filter_by.return_value.first.return_value = None
        return m
        
    mock_db_session.query.side_effect = query_side_effect

    with patch("src.api.auth.FitbitClient") as MockFitbitClient:
        instance = MockFitbitClient.return_value
        instance.exchange_code_for_token.return_value = {
            "access_token": "new_at",
            "refresh_token": "new_rt",
            "expires_in": 3600,
            "user_id": "uid",
            "scope": ["weight"]
        }

        payload = {"code": "auth_code_123"}
        response = client.post("/api/setup/fitbit/callback", json=payload)

        assert response.status_code == 200
        assert response.json()["status"] == "success"

        # Verify Token saved
        assert mock_db_session.add.called # APIToken added
        assert mock_db_session.commit.called

def test_fitbit_callback_no_config(client, mock_db_session):
    """Test callback fails if no config exists."""
    # Mock DB returns None for config
    def query_side_effect(model):
        m = MagicMock()
        if model == Configuration:
             m.first.return_value = None # No config
        return m
    mock_db_session.query.side_effect = query_side_effect
    
    payload = {"code": "auth_code_123"}
    response = client.post("/api/setup/fitbit/callback", json=payload)
    
    assert response.status_code == 400
    assert "Configuration missing" in response.json()["detail"]