sdb2-backend/app/utils/test_helpers.py

"""Test helper utilities for reducing code duplication."""

from contextlib import asynccontextmanager
from typing import Any, Dict, Optional, Type, TypeVar
from unittest.mock import AsyncMock

from fastapi import FastAPI
from sqlmodel.ext.asyncio.session import AsyncSession
from sqlmodel import SQLModel

from app.models.user import User
from app.utils.auth import JWTUtils

T = TypeVar("T", bound=SQLModel)


def create_jwt_token_data(user: User) -> Dict[str, str]:
    """Create standardized JWT token data dictionary for a user.
    
    Args:
        user: User object to create token data for
        
    Returns:
        Dictionary with sub, email, and role fields
    """
    return {
        "sub": str(user.id),
        "email": user.email,
        "role": user.role,
    }


def create_access_token_for_user(user: User) -> str:
    """Create an access token for a user using standardized token data.
    
    Args:
        user: User object to create token for
        
    Returns:
        JWT access token string
    """
    token_data = create_jwt_token_data(user)
    return JWTUtils.create_access_token(token_data)


async def create_and_save_model(
    session: AsyncSession, 
    model_class: Type[T],
    **kwargs: Any
) -> T:
    """Create, save, and refresh a model instance.
    
    This consolidates the common pattern of:
    - model = ModelClass(**kwargs)  
    - session.add(model)
    - await session.commit()
    - await session.refresh(model)
    
    Args:
        session: Database session
        model_class: SQLModel class to instantiate
        **kwargs: Arguments to pass to model constructor
        
    Returns:
        Created and refreshed model instance
    """
    instance = model_class(**kwargs)
    session.add(instance)
    await session.commit()
    await session.refresh(instance)
    return instance


@asynccontextmanager
async def override_dependencies(
    app: FastAPI,
    overrides: Dict[Any, Any]
):
    """Context manager for FastAPI dependency overrides with automatic cleanup.
    
    Args:
        app: FastAPI application instance
        overrides: Dictionary mapping dependency functions to mock implementations
        
    Usage:
        async with override_dependencies(test_app, {
            get_service: lambda: mock_service,
            get_repo: lambda: mock_repo
        }):
            # Test code here
            pass
        # Dependencies automatically cleaned up
    """
    # Apply overrides
    for dependency, override in overrides.items():
        app.dependency_overrides[dependency] = override
    
    try:
        yield
    finally:
        # Clean up overrides
        for dependency in overrides:
            app.dependency_overrides.pop(dependency, None)


def create_mock_vlc_services() -> Dict[str, AsyncMock]:
    """Create standard set of mocked VLC-related services.
    
    Returns:
        Dictionary with mocked vlc_service, sound_repository, and credit_service
    """
    return {
        "vlc_service": AsyncMock(),
        "sound_repository": AsyncMock(),
        "credit_service": AsyncMock(),
    }


def configure_mock_sound_play_success(
    mocks: Dict[str, AsyncMock],
    sound_data: Dict[str, Any]
) -> None:
    """Configure mocks for successful sound playback scenario.
    
    Args:
        mocks: Dictionary of mock services from create_mock_vlc_services()
        sound_data: Dictionary with sound properties (id, name, etc.)
    """
    from app.models.sound import Sound
    
    mock_sound = Sound(**sound_data)
    
    # Configure repository mock
    mocks["sound_repository"].get_by_id.return_value = mock_sound
    
    # Configure credit service mocks  
    mocks["credit_service"].validate_and_reserve_credits.return_value = None
    mocks["credit_service"].deduct_credits.return_value = None
    
    # Configure VLC service mock
    mocks["vlc_service"].play_sound.return_value = True


def create_mock_vlc_stop_result(
    success: bool = True,
    processes_found: int = 3,
    processes_killed: int = 3,
    processes_remaining: int = 0,
    message: Optional[str] = None,
    error: Optional[str] = None
) -> Dict[str, Any]:
    """Create standardized VLC stop operation result.
    
    Args:
        success: Whether operation succeeded
        processes_found: Number of VLC processes found
        processes_killed: Number of processes successfully killed
        processes_remaining: Number of processes still running
        message: Success/status message
        error: Error message (for failed operations)
        
    Returns:
        Dictionary with VLC stop operation result
    """
    result = {
        "success": success,
        "processes_found": processes_found,
        "processes_killed": processes_killed,
    }
    
    if not success:
        result["error"] = error or "Command failed"
        result["message"] = message or "Failed to stop VLC processes"
    else:
        # Always include processes_remaining for successful operations
        result["processes_remaining"] = processes_remaining
        result["message"] = message or f"Killed {processes_killed} VLC processes"
    
    return result