import pytest
from PIL import Image, WmfImagePlugin

from .helper import PillowTestCase, assert_image_similar, hopper


class TestFileWmf(PillowTestCase):
    def test_load_raw(self):

        # Test basic EMF open and rendering
        with Image.open("Tests/images/drawing.emf") as im:
            if hasattr(Image.core, "drawwmf"):
                # Currently, support for WMF/EMF is Windows-only
                im.load()
                # Compare to reference rendering
                with Image.open("Tests/images/drawing_emf_ref.png") as imref:
                    imref.load()
                    assert_image_similar(im, imref, 0)

        # Test basic WMF open and rendering
        with Image.open("Tests/images/drawing.wmf") as im:
            if hasattr(Image.core, "drawwmf"):
                # Currently, support for WMF/EMF is Windows-only
                im.load()
                # Compare to reference rendering
                with Image.open("Tests/images/drawing_wmf_ref.png") as imref:
                    imref.load()
                    assert_image_similar(im, imref, 2.0)

    def test_register_handler(self):
        class TestHandler:
            methodCalled = False

            def save(self, im, fp, filename):
                self.methodCalled = True

        handler = TestHandler()
        WmfImagePlugin.register_handler(handler)

        im = hopper()
        tmpfile = self.tempfile("temp.wmf")
        im.save(tmpfile)
        assert handler.methodCalled

        # Restore the state before this test
        WmfImagePlugin.register_handler(None)

    def test_load_dpi_rounding(self):
        # Round up
        with Image.open("Tests/images/drawing.emf") as im:
            assert im.info["dpi"] == 1424

        # Round down
        with Image.open("Tests/images/drawing_roundDown.emf") as im:
            assert im.info["dpi"] == 1426

    def test_load_set_dpi(self):
        with Image.open("Tests/images/drawing.wmf") as im:
            assert im.size == (82, 82)

            if hasattr(Image.core, "drawwmf"):
                im.load(144)
                assert im.size == (164, 164)

                with Image.open("Tests/images/drawing_wmf_ref_144.png") as expected:
                    assert_image_similar(im, expected, 2.0)

    def test_save(self):
        im = hopper()

        for ext in [".wmf", ".emf"]:
            tmpfile = self.tempfile("temp" + ext)
            with pytest.raises(IOError):
                im.save(tmpfile)