import unittest

import pytest

from shapely.algorithms.polylabel import Cell, polylabel
from shapely.errors import TopologicalError
from shapely.geometry import LineString, Point, Polygon


class PolylabelTestCase(unittest.TestCase):
    def test_polylabel(self):
        """
        Finds pole of inaccessibility for a polygon with a tolerance of 10

        """
        polygon = LineString(
            [(0, 0), (50, 200), (100, 100), (20, 50), (-100, -20), (-150, -200)]
        ).buffer(100)
        label = polylabel(polygon, tolerance=10)
        expected = Point(59.35615556364569, 121.8391962974644)
        assert expected.equals_exact(label, 1e-6)

    def test_invalid_polygon(self):
        """
        Makes sure that the polylabel function throws an exception when provided
        an invalid polygon.

        """
        bowtie_polygon = Polygon(
            [(0, 0), (0, 20), (10, 10), (20, 20), (20, 0), (10, 10), (0, 0)]
        )
        with pytest.raises(TopologicalError):
            polylabel(bowtie_polygon)

    def test_cell_sorting(self):
        """
        Tests rich comparison operators of Cells for use in the polylabel
        minimum priority queue.

        """
        polygon = Point(0, 0).buffer(100)
        cell1 = Cell(0, 0, 50, polygon)  # closest
        cell2 = Cell(50, 50, 50, polygon)  # furthest
        assert cell1 < cell2
        assert cell1 <= cell2
        assert (cell2 <= cell1) is False
        assert cell1 == cell1
        assert (cell1 == cell2) is False
        assert cell1 != cell2
        assert (cell1 != cell1) is False
        assert cell2 > cell1
        assert (cell1 > cell2) is False
        assert cell2 >= cell1
        assert (cell1 >= cell2) is False

    def test_concave_polygon(self):
        """
        Finds pole of inaccessibility for a concave polygon and ensures that
        the point is inside.

        """
        concave_polygon = LineString([(500, 0), (0, 0), (0, 500), (500, 500)]).buffer(
            100
        )
        label = polylabel(concave_polygon)
        assert concave_polygon.contains(label)

    def test_rectangle_special_case(self):
        """
        The centroid algorithm used is vulnerable to floating point errors
        and can give unexpected results for rectangular polygons. Test
        that this special case is handled correctly.
        https://github.com/mapbox/polylabel/issues/3
        """
        polygon = Polygon(
            [
                (32.71997, -117.19310),
                (32.71997, -117.21065),
                (32.72408, -117.21065),
                (32.72408, -117.19310),
            ]
        )
        label = polylabel(polygon)
        assert label.coords[:] == [(32.722025, -117.201875)]

    def test_polygon_with_hole(self):
        """
        Finds pole of inaccessibility for a polygon with a hole
        https://github.com/shapely/shapely/issues/817
        """
        polygon = Polygon(
            shell=[(0, 0), (10, 0), (10, 10), (0, 10), (0, 0)],
            holes=[[(2, 2), (6, 2), (6, 6), (2, 6), (2, 2)]],
        )
        label = polylabel(polygon, 0.05)
        assert label.x == pytest.approx(7.65625)
        assert label.y == pytest.approx(7.65625)