import pytest
import logging
import os
from io import BytesIO

import h5py


logger = logging.getLogger(__name__)


def _set_qt_binding(binding):
    if binding is not None:
        binding = binding.lower()
        if binding == "pyqt5":
            logger.info("Force using PyQt5")
            import PyQt5.QtCore  # noqa
        elif binding == "pyside6":
            logger.info("Force using PySide6")
            import PySide6.QtCore  # noqa
        elif binding == "pyqt6":
            logger.info("Force using PyQt6")
            import PyQt6.QtCore  # noqa
        else:
            raise ValueError("Qt binding '%s' is unknown" % binding)


def pytest_addoption(parser):
    parser.addoption(
        "--qt-binding",
        type=str,
        default=None,
        dest="qt_binding",
        help="Force using a Qt binding: 'PyQt5', 'PySide6', 'PyQt6'",
    )
    parser.addoption(
        "--no-gui",
        dest="gui",
        default=True,
        action="store_false",
        help="Disable the test of the graphical use interface",
    )
    parser.addoption(
        "--no-opengl",
        dest="opengl",
        default=True,
        action="store_false",
        help="Disable tests using OpenGL",
    )
    parser.addoption(
        "--no-opencl",
        dest="opencl",
        default=True,
        action="store_false",
        help="Disable the test of the OpenCL part",
    )
    parser.addoption(
        "--low-mem",
        dest="low_mem",
        default=False,
        action="store_true",
        help="Disable test with large memory consumption (>100Mbyte",
    )


def pytest_configure(config):
    if not config.getoption("opencl", True):
        os.environ["SILX_OPENCL"] = "False"  # Disable OpenCL support in silx

    _set_qt_binding(config.option.qt_binding)


@pytest.fixture(scope="session")
def test_options(request):
    from .test import utils

    options = utils._TestOptions()
    options.configure(request.config.option)
    yield options


@pytest.fixture(scope="class")
def test_options_class_attr(request, test_options):
    """Provides test_options as class attribute

    Used as transition from TestCase to pytest
    """
    request.cls.test_options = test_options


@pytest.fixture(scope="session")
def use_opengl(test_options):
    """Fixture to flag test using a OpenGL.

    This can be skipped with `--no-opengl`.
    """
    if not test_options.WITH_GL_TEST:
        pytest.skip(test_options.WITH_GL_TEST_REASON, allow_module_level=True)


@pytest.fixture(scope="session")
def use_opencl(test_options):
    """Fixture to flag test using a OpenCL.

    This can be skipped with `--no-opencl`.
    """
    if not test_options.WITH_OPENCL_TEST:
        pytest.skip(test_options.WITH_OPENCL_TEST_REASON, allow_module_level=True)


@pytest.fixture(scope="session")
def use_large_memory(test_options):
    """Fixture to flag test using a large memory consumption.

    This can be skipped with `--low-mem`.
    """
    if test_options.TEST_LOW_MEM:
        pytest.skip(test_options.TEST_LOW_MEM_REASON, allow_module_level=True)


@pytest.fixture(scope="session")
def use_gui(test_options):
    """Fixture to flag test using GUI.

    This can be skipped with `--no-gui`.
    """
    if not test_options.WITH_QT_TEST:
        pytest.skip(test_options.WITH_QT_TEST_REASON, allow_module_level=True)


@pytest.fixture(scope="session")
def qapp(use_gui, xvfb, request):
    _set_qt_binding(request.config.option.qt_binding)

    from silx.gui import qt

    app = qt.QApplication.instance()
    if app is None:
        app = qt.QApplication([])
    try:
        yield app
    finally:
        if app is not None:
            app.closeAllWindows()


@pytest.fixture
def qapp_utils(qapp):
    """Helper containing method to deal with QApplication and widget"""
    from silx.gui.utils.testutils import TestCaseQt

    utils = TestCaseQt()
    utils.setUpClass()
    utils.setUp()
    yield utils
    utils.tearDown()
    utils.tearDownClass()


@pytest.fixture
def tmp_h5py_file():
    with BytesIO() as buffer:
        with h5py.File(buffer, mode="w") as h5file:
            yield h5file