from typing import Generator

import pytest
from fastapi.testclient import TestClient
from sqlalchemy import create_engine
from sqlalchemy.orm import Session, sessionmaker
from sqlalchemy.pool import StaticPool

from config.database import Base
from main import app

SQLALCHEMY_TEST_URL = "sqlite:///:memory:"
engine = create_engine(
    SQLALCHEMY_TEST_URL,
    connect_args={"check_same_thread": False},
    poolclass=StaticPool,
)
TestingSessionLocal = sessionmaker(
    autocommit=False, autoflush=False, bind=engine)


@pytest.fixture(scope="session", autouse=True)
def setup_database() -> Generator[None, None, None]:
    # Ensure all model metadata is registered before creating tables
    from models import (
        capex,
        consumption,
        distribution,
        equipment,
        maintenance,
        opex,
        parameters,
        production_output,
        scenario,
        simulation_result,
    )  # noqa: F401 - imported for side effects

    Base.metadata.create_all(bind=engine)
    yield
    Base.metadata.drop_all(bind=engine)


@pytest.fixture()
def db_session() -> Generator[Session, None, None]:
    session = TestingSessionLocal()
    try:
        yield session
    finally:
        session.close()


@pytest.fixture()
def api_client(db_session: Session) -> Generator[TestClient, None, None]:
    def override_get_db():
        try:
            yield db_session
        finally:
            pass

    # override all routers that use get_db
    from routes import (
        consumption,
        costs,
        distributions,
        equipment,
        maintenance,
        parameters,
        production,
        reporting,
        scenarios,
        simulations,
    )

    overrides = {
        consumption.get_db: override_get_db,
        costs.get_db: override_get_db,
        distributions.get_db: override_get_db,
        equipment.get_db: override_get_db,
        maintenance.get_db: override_get_db,
        parameters.get_db: override_get_db,
        production.get_db: override_get_db,
        reporting.get_db: override_get_db,
        scenarios.get_db: override_get_db,
        simulations.get_db: override_get_db,
    }

    for dependency, override in overrides.items():
        app.dependency_overrides[dependency] = override

    with TestClient(app) as client:
        yield client

    for dependency in overrides:
        app.dependency_overrides.pop(dependency, None)