import cv2
import numpy as np
import pytest

from cv_analysis.figure_detection.text import (
    remove_primary_text_regions,
    apply_threshold_to_image,
)
from test.utils.utils import powerset


@pytest.mark.parametrize("error_tolerance", [0.07])
@pytest.mark.parametrize("background_color", [255, 220])
class TestFindPrimaryTextRegions:
    def test_blank_page_stays_blank(self, background, error_tolerance):
        result_page = remove_primary_text_regions(background)

        np.testing.assert_equal(result_page, apply_threshold_to_image(background))

    @pytest.mark.parametrize("image_size", [(200, 200), (500, 500), (800, 800)])
    def test_page_without_text_keeps_images(self, page_with_images, error_tolerance):
        result_page = remove_primary_text_regions(page_with_images)
        np.testing.assert_equal(result_page, apply_threshold_to_image(page_with_images))

    @pytest.mark.parametrize("font_scale", [1, 1.5, 2])
    @pytest.mark.parametrize("font_style", [cv2.FONT_HERSHEY_SIMPLEX, cv2.FONT_HERSHEY_COMPLEX])
    @pytest.mark.parametrize("text_types", powerset(["body", "header", "caption"]))
    def test_page_with_only_text_gets_text_removed(self, page_with_text, error_tolerance):
        result_page = remove_primary_text_regions(page_with_text)
        relative_error = np.sum(result_page != apply_threshold_to_image(page_with_text)) / result_page.size
        assert relative_error <= error_tolerance

    @pytest.mark.parametrize("image_size", [(200, 200), (500, 500), (800, 800)])
    @pytest.mark.parametrize("font_scale", [1, 1.5, 2])
    @pytest.mark.parametrize("font_style", [cv2.FONT_HERSHEY_SIMPLEX, cv2.FONT_HERSHEY_COMPLEX])
    @pytest.mark.parametrize("text_types", powerset(["body", "header", "caption"]))
    def test_page_with_images_and_text_keeps_images(self, page_with_images_and_text, error_tolerance):
        result_page = remove_primary_text_regions(page_with_images_and_text)
        relative_error = np.sum(result_page != apply_threshold_to_image(page_with_images_and_text)) / result_page.size
        assert relative_error <= error_tolerance
