import pytest
from fastapi.testclient import TestClient
from app.main import app
from app.database import get_db, Base
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker

TEST_DATABASE_URL = "postgresql://postgres:postgres@localhost:5432/test_db"

@pytest.fixture(scope="session")
def test_engine():
    engine = create_engine(TEST_DATABASE_URL)
    Base.metadata.create_all(bind=engine)
    yield engine
    Base.metadata.drop_all(bind=engine)

@pytest.fixture
def db_session(test_engine):
    connection = test_engine.connect()
    transaction = connection.begin()
    session = sessionmaker(autocommit=False, autoflush=False, bind=connection)()
    yield session
    session.close()
    transaction.rollback()
    connection.close()

@pytest.fixture
def client(db_session):
    def override_get_db():
        try:
            yield db_session
        finally:
            db_session.close()
    
    app.dependency_overrides[get_db] = override_get_db
    return TestClient(app)