from fastapi.testclient import TestClient
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker

from main import app
from config.db import get_db

from models.ml import MLModel

import uuid
from datetime import datetime, timezone


def test_list_models_simple(tmp_path):
    db_path = tmp_path / "testing.db"
    engine = create_engine(
        f"sqlite:///{db_path}",
        connect_args={"check_same_thread": False},
        future=True,
    )
    SQLSession = sessionmaker(bind=engine, autoflush=False, autocommit=False, future=True)

    MLModel.metadata.create_all(engine) 

    session = SQLSession()

    def get_db_override():
        return session

    app.dependency_overrides[get_db] = get_db_override

    client = TestClient(app, raise_server_exceptions=False)

    created = datetime(2025, 9, 15, 10, 11, 3, 950802, tzinfo=timezone.utc)
    session.add_all(
        [
            MLModel(
                id=uuid.UUID("5b1c7b3a-0000-4000-8000-000000000001"),
                name="baseline",
                description="Baseline model",
                created_at=created,
                is_active=True,
            ),
            MLModel(
                id=uuid.UUID("5b1c7b3a-0000-4000-8000-000000000002"),
                name="best_model",
                description="XGB v1",
                created_at=created,
                is_active=True,
            ),
             MLModel(
                id=uuid.UUID("5b1c7b3a-0000-4000-8000-000000000003"),
                name="logistic_regression",
                description="Logistic Regression",
                created_at=created,
                is_active=True,
            ),
        ]
    )
    session.commit()

    resp = client.get("/")


    app.dependency_overrides.clear()
    session.close()

    assert resp.status_code == 200
    data = resp.json()
    names = {row["name"] for row in data}
    assert names == {"baseline", "best_model", 'logistic_regression'}


def test_list_models_returns_500_when_db_fails():
    class BrokenSession:
        def query(self, *a, **kw):
            raise RuntimeError("DB is down")

    def get_db_override():
        yield BrokenSession()

    app.dependency_overrides[get_db] = get_db_override
    client = TestClient(app, raise_server_exceptions=False)

    resp = client.get("/")

    app.dependency_overrides.clear()

    assert resp.status_code == 500
    body = resp.json()
    assert "DB is down" in body["detail"]