import mapnik
import os
import pytest

from .utilities import execution_path

@pytest.fixture(scope="module")
def setup():
    # All of the paths used are relative, if we run the tests
    # from another directory we need to chdir()
    os.chdir(execution_path('.'))
    yield

if mapnik.has_webp():
    tmp_dir = '/tmp/mapnik-webp/'
    if not os.path.exists(tmp_dir):
        os.makedirs(tmp_dir)

    opts = [
        'webp',
        'webp:method=0',
        'webp:method=6',
        'webp:quality=64',
        'webp:alpha=false',
        'webp:partitions=3',
        'webp:preprocessing=1',
        'webp:partition_limit=50',
        'webp:pass=10',
        'webp:alpha_quality=50',
        'webp:alpha_filtering=2',
        'webp:alpha_compression=0',
        'webp:autofilter=0',
        'webp:filter_type=1:autofilter=1',
        'webp:filter_sharpness=4',
        'webp:filter_strength=50',
        'webp:sns_strength=50',
        'webp:segments=3',
        'webp:target_PSNR=.5',
        'webp:target_size=100'
    ]

    def gen_filepath(name, format):
        return os.path.join('images/support/encoding-opts',
                            name + '-' + format.replace(":", "+") + '.webp')

    def test_quality_threshold(setup):
        im = mapnik.Image(256, 256)
        im.to_string('webp:quality=99.99000')
        im.to_string('webp:quality=0')
        im.to_string('webp:quality=0.001')


    def test_quality_threshold_invalid():
        im = mapnik.Image(256, 256)
        with pytest.raises(RuntimeError):
            im.to_string('webp:quality=101')


    def test_quality_threshold_invalid2():
        im = mapnik.Image(256, 256)
        with pytest.raises(RuntimeError):
            im.to_string('webp:quality=-1')

    def test_quality_threshold_invalid3():
        im = mapnik.Image(256, 256)
        with pytest.raises(RuntimeError):
            im.to_string('webp:quality=101.1')

    generate = os.environ.get('UPDATE')

    def test_expected_encodings():
        fails = []
        try:
            for opt in opts:
                im = mapnik.Image(256, 256)
                expected = gen_filepath('blank', opt)
                actual = os.path.join(tmp_dir, os.path.basename(expected))
                if generate or not os.path.exists(expected):
                    print('generating expected image', expected)
                    im.save(expected, opt)
                im.save(actual, opt)
                try:
                    expected_bytes = mapnik.Image.open(expected).to_string()
                except RuntimeError:
                    # this will happen if libweb is old, since it cannot open
                    # images created by more recent webp
                    print(
                        'warning, cannot open webp expected image (your libwebp is likely too old)')
                    continue
                if mapnik.Image.open(actual).to_string() != expected_bytes:
                    fails.append(
                        '%s (actual) not == to %s (expected)' %
                        (actual, expected))

            for opt in opts:
                im = mapnik.Image(256, 256)
                im.fill(mapnik.Color('green'))
                expected = gen_filepath('solid', opt)
                actual = os.path.join(tmp_dir, os.path.basename(expected))
                if generate or not os.path.exists(expected):
                    print('generating expected image', expected)
                    im.save(expected, opt)
                im.save(actual, opt)
                try:
                    expected_bytes = mapnik.Image.open(expected).to_string()
                except RuntimeError:
                    # this will happen if libweb is old, since it cannot open
                    # images created by more recent webp
                    print(
                        'warning, cannot open webp expected image (your libwebp is likely too old)')
                    continue
                if mapnik.Image.open(actual).to_string() != expected_bytes:
                    fails.append(
                        '%s (actual) not == to %s (expected)' %
                        (actual, expected))

            for opt in opts:
                im = mapnik.Image.open(
                    'images/support/transparency/aerial_rgba.png')
                expected = gen_filepath('aerial_rgba', opt)
                actual = os.path.join(tmp_dir, os.path.basename(expected))
                if generate or not os.path.exists(expected):
                    print('generating expected image', expected)
                    im.save(expected, opt)
                im.save(actual, opt)
                try:
                    expected_bytes = mapnik.Image.open(expected).to_string()
                except RuntimeError:
                    # this will happen if libweb is old, since it cannot open
                    # images created by more recent webp
                    print(
                        'warning, cannot open webp expected image (your libwebp is likely too old)')
                    continue
                if mapnik.Image.open(actual).to_string() != expected_bytes:
                    fails.append(
                        '%s (actual) not == to %s (expected)' %
                        (actual, expected))
            # disabled to avoid failures on ubuntu when using old webp packages
            # assert fails,[] == '\n'+'\n'.join(fails)
        except RuntimeError as e:
            print(e)

    def test_transparency_levels():
        try:
            # create partial transparency image
            im = mapnik.Image(256, 256)
            im.fill(mapnik.Color('rgba(255,255,255,.5)'))
            c2 = mapnik.Color('rgba(255,255,0,.2)')
            c3 = mapnik.Color('rgb(0,255,255)')
            for y in range(0, int(im.height() / 2)):
                for x in range(0, int(im.width() / 2)):
                    im.set_pixel(x, y, c2)
            for y in range(int(im.height() / 2), im.height()):
                for x in range(int(im.width() / 2), im.width()):
                    im.set_pixel(x, y, c3)

            t0 = tmp_dir + 'white0-actual.webp'

            # octree
            format = 'webp'
            expected = 'images/support/transparency/white0.webp'
            if generate or not os.path.exists(expected):
                im.save('images/support/transparency/white0.webp')
            im.save(t0, format)
            im_in = mapnik.Image.open(t0)
            t0_len = len(im_in.to_string(format))
            try:
                expected_bytes = mapnik.Image.open(expected).to_string(format)
            except RuntimeError:
                # this will happen if libweb is old, since it cannot open
                # images created by more recent webp
                print(
                    'warning, cannot open webp expected image (your libwebp is likely too old)')
                return
            assert t0_len ==  len(expected_bytes)
        except RuntimeError as e:
            print(e)