import pytest
from unittest import mock
import os
import tempfile

import pandas as pd

import laser_echo_analysis.visualization as viz

@pytest.fixture
def sample_analysis_results():
    return {
        'peak': 12345,
        'average_noise': 12.3,
        'signal_to_noise_ratio': 1003.66
    }


def test_visualize_results_creates_plot_file(sample_analysis_results):
    with tempfile.TemporaryDirectory() as tmpdir:
        plot_path = os.path.join(tmpdir, 'laser_analysis_plot.png')

        # Patch plt.savefig to simulate file creation and speed up tests
        with mock.patch('matplotlib.pyplot.savefig') as mock_save:
            mock_save.side_effect = lambda path, *a, **kw: open(path, 'w').close()
            viz.visualize_results(sample_analysis_results)
            mock_save.assert_called()

        # ensure temporary directory is usable within test
        # simulate writing to a desired path
        with mock.patch('matplotlib.pyplot.savefig') as mock_save_2:
            mock_save_2.side_effect = lambda path, *a, **kw: open(plot_path, 'w').close()
            viz.visualize_results(sample_analysis_results)
            assert os.path.exists(plot_path), 'Plot file was not created.'


def test_visualize_results_handles_invalid_input_types():
    with pytest.raises((TypeError, ValueError)):
        viz.visualize_results('not_a_dict')


def test_visualize_results_missing_keys(monkeypatch):
    partial_result = {'peak': 12}
    with pytest.raises(KeyError):
        viz.visualize_results(partial_result)


def test_visualize_results_plot_data_sample(sample_analysis_results):
    # Mock plt.show and plt.savefig to ensure no GUI is opened
    with mock.patch('matplotlib.pyplot.show') as mock_show, \
         mock.patch('matplotlib.pyplot.savefig') as mock_save:
        viz.visualize_results(sample_analysis_results)
        mock_save.assert_called()
        mock_show.assert_not_called()

        # call count sanity check
        assert mock_save.call_count >= 1