from fastapi.testclient import TestClient
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
from main import app
from models import Base

engine = create_engine("sqlite:///:memory:", connect_args={"check_same_thread": False})
TestSession = sessionmaker(bind=engine)
Base.metadata.create_all(bind=engine)

def override_get_db():
    db = TestSession()
    try:
        yield db
    finally:
        db.close()

app.dependency_overrides[get_db] = override_get_db
client = TestClient(app)

def test_create_task():
    response = client.post("/tasks/", json={"title": "Test Task", "description": "This is a test task"})
    assert response.status_code == 201
    assert response.json()["title"] == "Test Task"
    assert response.json()["description"] == "This is a test task"

def test_get_tasks():
    response = client.get("/tasks/")
    assert response.status_code == 200
    assert len(response.json()) > 0

def test_get_task_by_id():
    response = client.post("/tasks/", json={"title": "Test Task", "description": "This is a test task"})
    task_id = response.json()["id"]
    response = client.get(f"/tasks/{task_id}")
    assert response.status_code == 200
    assert response.json()["id"] == task_id

def test_get_task_by_id_not_found():
    response = client.get("/tasks/999")
    assert response.status_code == 404

def test_update_task():
    response = client.post("/tasks/", json={"title": "Test Task", "description": "This is a test task"})
    task_id = response.json()["id"]
    updated_data = {"title": "Updated Test Task"}
    response = client.put(f"/tasks/{task_id}", json=updated_data)
    assert response.status_code == 200
    assert response.json()["title"] == "Updated Test Task"

def test_delete_task():
    response = client.post("/tasks/", json={"title": "Test Task", "description": "This is a test task"})
    task_id = response.json()["id"]
    response = client.delete(f"/tasks/{task_id}")
    assert response.status_code == 204
    response = client.get(f"/tasks/{task_id}")
    assert response.status_code == 404