import pytest
from unittest.mock import MagicMock, patch
from fastapi.testclient import TestClient
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
from datetime import datetime, timedelta

# Import models and app
from src.models import Base, Configuration, APIToken
from main import app
from src.api.setup import get_db

# Setup in-memory DB for tests
SQLALCHEMY_DATABASE_URL = "sqlite:///:memory:"
engine = create_engine(SQLALCHEMY_DATABASE_URL, connect_args={"check_same_thread": False})
TestingSessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)

@pytest.fixture(scope="module")
def db_engine():
    Base.metadata.create_all(bind=engine)
    yield engine
    Base.metadata.drop_all(bind=engine)

@pytest.fixture(scope="function")
def db(db_engine):
    connection = db_engine.connect()
    transaction = connection.begin()
    session = TestingSessionLocal(bind=connection)
    yield session
    session.close()
    transaction.rollback()
    connection.close()

@pytest.fixture(scope="function")
def client(db):
    def override_get_db():
        try:
            yield db
        finally:
            pass
    app.dependency_overrides[get_db] = override_get_db
    yield TestClient(app)
    del app.dependency_overrides[get_db]

def test_save_fitbit_credentials(client, db):
    """Test saving Fitbit credentials and generating auth URL."""
    payload = {
        "client_id": "test_client_id",
        "client_secret": "test_client_secret"
    }
    
    # Needs to match the Pydantic model we will create
    response = client.post("/api/setup/fitbit", json=payload)
    
    assert response.status_code == 200
    data = response.json()
    assert "auth_url" in data
    assert "https://www.fitbit.com/oauth2/authorize" in data["auth_url"]
    assert "client_id=test_client_id" in data["auth_url"]
    
    # Verify DB
    config = db.query(Configuration).first()
    assert config is not None
    assert config.fitbit_client_id == "test_client_id"
    assert config.fitbit_client_secret == "test_client_secret"

@patch("src.api.setup.FitbitClient")
def test_fitbit_callback_success(mock_fitbit_cls, client, db):
    """Test Fitbit OAuth callback success."""
    # Setup initial config
    config_entry = Configuration(fitbit_client_id="cid", fitbit_client_secret="csec")
    db.add(config_entry)
    db.commit()

    # Mock FitbitClient instance and method
    mock_instance = MagicMock()
    mock_fitbit_cls.return_value = mock_instance
    mock_instance.exchange_code_for_token.return_value = {
        "access_token": "new_at",
        "refresh_token": "new_rt",
        "expires_at": 3600, # seconds
        "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
    token = db.query(APIToken).filter_by(token_type="fitbit").first()
    assert token is not None
    assert token.access_token == "new_at"
    assert token.refresh_token == "new_rt"

@patch("src.api.setup.FitbitClient")
def test_fitbit_callback_no_config(mock_fitbit_cls, client, db):
    """Test callback fails if no config exists."""
    payload = {"code": "auth_code_123"}
    response = client.post("/api/setup/fitbit/callback", json=payload)
    
    assert response.status_code == 400
    assert "Configuration not found" in response.json()["detail"]