"""Unit tests for the IDS Camera device."""

import threading
from unittest import mock

import numpy as np
import pytest

from csaxs_bec.devices.ids_cameras.ids_camera import IDSCamera


@pytest.fixture(scope="function")
def ids_camera():
    """Fixture for creating an instance of the IDSCamera."""
    camera = IDSCamera(
        name="test_camera",
        camera_id=1,
        prefix="test:",
        scan_info=None,
        m_n_colormode=1,
        bits_per_pixel=24,
        live_mode=False,
    )
    # Mock camera connection and attributes
    camera.cam = mock.Mock()
    camera.cam._connected = True
    camera.cam.cam = mock.Mock()
    camera.cam.cam.width.value = 2
    camera.cam.cam.height.value = 2
    yield camera


def test_mask_setter_getter(ids_camera):
    """Test the mask setter and getter methods."""
    mask = np.zeros((2, 2), dtype=np.uint8)
    mask[0, 0] = 1
    ids_camera.mask = mask
    assert np.array_equal(ids_camera.mask, mask)


def test_mask_setter_invalid_shape(ids_camera):
    """Test the mask setter with an invalid shape."""
    with pytest.raises(ValueError):
        ids_camera.mask = np.zeros((3, 3), dtype=np.uint8)  # Exceeds mocked camera dimensions


def test_on_connected_sets_mask_and_live_mode(ids_camera):
    """Test the on_connected method to ensure it sets the mask and live mode."""
    ids_camera.cam.on_connect = mock.Mock()
    ids_camera.on_connected()
    ids_camera.cam.on_connect.assert_called_once()
    expected_mask = np.ones((2, 2), dtype=np.uint8)
    assert np.array_equal(ids_camera.mask, expected_mask)


def test_on_trigger_roi_signal(ids_camera):
    """Test the on_trigger method to ensure it processes the ROI signal correctly."""
    ids_camera.start_live_mode()
    test_image = np.array([[2, 4], [6, 8]])
    test_mask = np.array([[1, 0], [0, 1]], dtype=np.uint8)
    ids_camera.mask = test_mask
    mock_image = mock.Mock()
    mock_image.data = test_image
    ids_camera.image.get = mock.Mock(return_value=mock_image)
    ids_camera.roi_signal.put = mock.Mock(side_effect=ids_camera.roi_signal.put)
    ids_camera.on_trigger()
    expected_value = (2 * 1 + 4 * 0 + 6 * 0 + 8 * 1) / (np.sum(test_mask) * 1)
    result = ids_camera.roi_signal.get()
    assert np.isclose(
        result.content["signals"][ids_camera.roi_signal.name]["value"], expected_value, atol=1e-6
    )


def test_get_last_image(ids_camera):
    """Test the get_last_image method to ensure it returns the last captured image."""
    test_image = np.array([[1, 2], [3, 4]], dtype=np.uint8)
    mock_image = mock.Mock()
    mock_image.data = test_image
    ids_camera.image.get = mock.Mock(return_value=mock_image)

    result = ids_camera.get_last_image()
    assert np.array_equal(result, test_image)


def test_get_live_fps_none_before_frames(ids_camera):
    """No frames pushed yet -> get_live_fps() returns None."""
    assert ids_camera.get_live_fps() is None


def test_get_live_fps_computes_rate(ids_camera):
    """get_live_fps() computes rate from the recorded push timestamps."""
    ids_camera._live_frame_times.extend([0.0, 0.2, 0.4, 0.6, 0.8])
    assert ids_camera.get_live_fps() == pytest.approx(5.0)


def test_live_mode_loop_records_frame_times(ids_camera):
    """_live_mode_loop() appends one timestamp per pushed frame."""
    ids_camera.cam.get_image_data = mock.Mock(return_value=np.zeros((2, 2), dtype=np.uint8))
    stop_event = threading.Event()
    calls = {"n": 0}

    def fake_wait(timeout):
        calls["n"] += 1
        if calls["n"] >= 3:
            stop_event.set()
        return False

    stop_event.wait = fake_wait
    ids_camera._live_mode_loop(stop_event)

    assert len(ids_camera._live_frame_times) == 3
    assert ids_camera.get_live_fps() is not None


def test_on_destroy(ids_camera):
    """Test the on_destroy method to ensure it cleans up resources."""
    ids_camera.cam.on_disconnect = mock.Mock()
    ids_camera.on_destroy()
    ids_camera.cam.on_disconnect.assert_called_once()


def test_push_preview_image_compensates_rotation_and_transpose():
    """push_preview_image() is meant for data already display-oriented (e.g.
    built from get_last_image() frames, which already have num_rotation_90/
    transpose applied by PreviewSignal.put()). Pushing it through must undo
    that transform first so put()'s own transform doesn't apply it twice --
    net effect: what comes back out via .get() matches what went in.
    """
    camera = IDSCamera(
        name="test_camera_rot",
        camera_id=1,
        prefix="test:",
        scan_info=None,
        m_n_colormode=1,
        bits_per_pixel=24,
        live_mode=False,
        num_rotation_90=3,
        transpose=True,
    )
    camera.cam = mock.Mock()
    camera.cam._connected = True

    display_oriented = np.arange(12, dtype=np.uint8).reshape(3, 4)
    camera.push_preview_image(display_oriented)

    result = camera.image.get().data
    assert np.array_equal(result, display_oriented)


def test_push_smear_preview_no_rotation_compensation(ids_camera):
    """smear_preview has no rotation_90/transpose configured, so pushed data
    passes straight through unmodified -- unlike push_preview_image, no
    compensation is needed (or applied)."""
    data = np.arange(4, dtype=np.uint8).reshape(2, 2)
    ids_camera.push_smear_preview(data)

    result = ids_camera.smear_preview.get().data
    assert np.array_equal(result, data)