"""Tests for image_validator module."""
from io import BytesIO

from PIL import Image
import pytest
from src import image_validator


def build_test_image(size, mode, fmt, convert=None):
    """Utils returns an image."""
    file = BytesIO()
    image = Image.new(mode, size=size, color=(155, 0, 0))
    if convert:
        image = image.convert(convert)
    image.save(file, fmt)
    file.name = 'test.{}'.format(fmt)
    file.seek(0)
    return file


@pytest.mark.parametrize('test_image', [
    build_test_image((3000, 3000), 'RGB', 'jpeg'),
    build_test_image((4000, 4000), 'RGBA', 'tiff'),
    build_test_image((6000, 6000), 'RGB', 'jpeg', 'L')
])
def test_validate_image_success(test_image):
    """Test for a successful return when all validations pass."""
    result = image_validator.validate_image(test_image)
    assert result is True


@pytest.mark.parametrize('test_image,expected_error_code', [
    (build_test_image((2000, 2000), 'RGB', 'jpeg'), 'image_too_small_dimensions_error'),
    (build_test_image((6100, 6100), 'RGB', 'jpeg'), 'image_too_large_dimensions_error'),
    (build_test_image((3000, 4000), 'RGB', 'jpeg'), 'image_wrong_aspect_ratio_error')
])
def test_validate_image_invalid_dimensions(test_image, expected_error_code):
    """Test that validation fails if the dimensions are wrong."""
    with pytest.raises(image_validator.InvalidImageDimensions) as err:
        image_validator.validate_image(test_image)
    assert err.value.error_code == expected_error_code


@pytest.mark.parametrize('test_image,color_mode', [
    (build_test_image((3000, 3000), 'CMYK', 'jpeg'), 'CMYK'),
    (build_test_image((3000, 3000), 'RGB', 'tiff', 'P'), 'P')
])
def test_validate_image_invalid_color(test_image, color_mode):
    """Test that validation fails for invalid color."""
    with pytest.raises(image_validator.InvalidImageColor) as err:
        image_validator.validate_image(test_image)
    assert str(err.value) == 'Image has invalid color mode: {}'.format(color_mode)


def test_validate_image_invalid_file():
    """Test validation handles invalid files."""
    with pytest.raises(image_validator.InvalidImageError) as err:
        image_validator.validate_image(BytesIO())
    assert err.value.error_code == 'image_invalid_file'
    assert str(err.value) == 'Image is an invalid file: it can not be identified by PIL.'