from __future__ import annotations

import warnings
from typing import Generator

import pytest

from PIL import Image

with warnings.catch_warnings():
    warnings.simplefilter("ignore", category=DeprecationWarning)
    from PIL import ImageQt

from .helper import assert_image_equal, hopper

pytestmark = pytest.mark.skipif(
    not ImageQt.qt_is_installed, reason="Qt bindings are not installed"
)


@pytest.fixture
def test_images() -> Generator[Image.Image, None, None]:
    ims = [
        hopper(),
        Image.open("Tests/images/transparent.png"),
        Image.open("Tests/images/7x13.png"),
    ]
    try:
        yield ims
    finally:
        for im in ims:
            im.close()


def roundtrip(expected: Image.Image) -> None:
    # PIL -> Qt
    intermediate = expected.toqimage()
    # Qt -> PIL
    result = ImageQt.fromqimage(intermediate)

    if intermediate.hasAlphaChannel():
        assert_image_equal(result, expected.convert("RGBA"))
    else:
        assert_image_equal(result, expected.convert("RGB"))


def test_sanity_1(test_images: Generator[Image.Image, None, None]) -> None:
    for im in test_images:
        roundtrip(im.convert("1"))


def test_sanity_rgb(test_images: Generator[Image.Image, None, None]) -> None:
    for im in test_images:
        roundtrip(im.convert("RGB"))


def test_sanity_rgba(test_images: Generator[Image.Image, None, None]) -> None:
    for im in test_images:
        roundtrip(im.convert("RGBA"))


def test_sanity_l(test_images: Generator[Image.Image, None, None]) -> None:
    for im in test_images:
        roundtrip(im.convert("L"))


def test_sanity_p(test_images: Generator[Image.Image, None, None]) -> None:
    for im in test_images:
        roundtrip(im.convert("P"))