import pytest
from app import capture_rtsp_frames
from unittest.mock import patch
import cv2

@patch('cv2.VideoCapture')
def test_rtsp_connection(mock_video_capture):
    # Mock VideoCapture to simulate a successful connection
    mock_instance = mock_video_capture.return_value
    mock_instance.isOpened.return_value = True
    mock_instance.read.side_effect = [(True, None), (False, None)]  # Simulate one frame then stop
    
    rtsp_url = "rtsp://test:8554/stream"
    frames = list(capture_rtsp_frames(rtsp_url))  # Consume generator
    assert len(frames) == 1, "Expected one frame from mocked RTSP stream"
    mock_video_capture.assert_called_with(rtsp_url)
    mock_instance.release.assert_called_once()