import io
import sys
import unittest

import pytest
from PIL import IcnsImagePlugin, Image

from .helper import PillowTestCase, assert_image_equal, assert_image_similar

# sample icon file
TEST_FILE = "Tests/images/pillow.icns"

enable_jpeg2k = hasattr(Image.core, "jp2klib_version")


class TestFileIcns(PillowTestCase):
    def test_sanity(self):
        # Loading this icon by default should result in the largest size
        # (512x512@2x) being loaded
        with Image.open(TEST_FILE) as im:

            # Assert that there is no unclosed file warning
            pytest.warns(None, im.load)

            assert im.mode == "RGBA"
            assert im.size == (1024, 1024)
            assert im.format == "ICNS"

    @unittest.skipIf(sys.platform != "darwin", "requires macOS")
    def test_save(self):
        temp_file = self.tempfile("temp.icns")

        with Image.open(TEST_FILE) as im:
            im.save(temp_file)

        with Image.open(temp_file) as reread:
            assert reread.mode == "RGBA"
            assert reread.size == (1024, 1024)
            assert reread.format == "ICNS"

    @unittest.skipIf(sys.platform != "darwin", "requires macOS")
    def test_save_append_images(self):
        temp_file = self.tempfile("temp.icns")
        provided_im = Image.new("RGBA", (32, 32), (255, 0, 0, 128))

        with Image.open(TEST_FILE) as im:
            im.save(temp_file, append_images=[provided_im])

            with Image.open(temp_file) as reread:
                assert_image_similar(reread, im, 1)

            with Image.open(temp_file) as reread:
                reread.size = (16, 16, 2)
                reread.load()
                assert_image_equal(reread, provided_im)

    def test_sizes(self):
        # Check that we can load all of the sizes, and that the final pixel
        # dimensions are as expected
        with Image.open(TEST_FILE) as im:
            for w, h, r in im.info["sizes"]:
                wr = w * r
                hr = h * r
                im.size = (w, h, r)
                im.load()
                assert im.mode == "RGBA"
                assert im.size == (wr, hr)

            # Check that we cannot load an incorrect size
            with pytest.raises(ValueError):
                im.size = (1, 1)

    def test_older_icon(self):
        # This icon was made with Icon Composer rather than iconutil; it still
        # uses PNG rather than JP2, however (since it was made on 10.9).
        with Image.open("Tests/images/pillow2.icns") as im:
            for w, h, r in im.info["sizes"]:
                wr = w * r
                hr = h * r
                with Image.open("Tests/images/pillow2.icns") as im2:
                    im2.size = (w, h, r)
                    im2.load()
                    assert im2.mode == "RGBA"
                    assert im2.size == (wr, hr)

    def test_jp2_icon(self):
        # This icon was made by using Uli Kusterer's oldiconutil to replace
        # the PNG images with JPEG 2000 ones.  The advantage of doing this is
        # that OS X 10.5 supports JPEG 2000 but not PNG; some commercial
        # software therefore does just this.

        # (oldiconutil is here: https://github.com/uliwitness/oldiconutil)

        if not enable_jpeg2k:
            return

        with Image.open("Tests/images/pillow3.icns") as im:
            for w, h, r in im.info["sizes"]:
                wr = w * r
                hr = h * r
                with Image.open("Tests/images/pillow3.icns") as im2:
                    im2.size = (w, h, r)
                    im2.load()
                    assert im2.mode == "RGBA"
                    assert im2.size == (wr, hr)

    def test_getimage(self):
        with open(TEST_FILE, "rb") as fp:
            icns_file = IcnsImagePlugin.IcnsFile(fp)

            im = icns_file.getimage()
            assert im.mode == "RGBA"
            assert im.size == (1024, 1024)

            im = icns_file.getimage((512, 512))
            assert im.mode == "RGBA"
            assert im.size == (512, 512)

    def test_not_an_icns_file(self):
        with io.BytesIO(b"invalid\n") as fp:
            with pytest.raises(SyntaxError):
                IcnsImagePlugin.IcnsFile(fp)