import numpy as np

from pipeline.vectorize import rdp, rasterize, trace, vectorize_frame


def test_rdp_drops_collinear_point():
    pts = [(0, 0), (1, 0), (2, 0)]
    assert rdp(pts, 0.5) == [(0, 0), (2, 0)]


def test_rasterize_square():
    poly = [[(1, 1), (4, 1), (4, 4), (1, 4), (1, 1)]]
    out = rasterize([poly], 6, 6)
    assert out[2, 2]
    assert not out[0, 0]


def test_rasterize_square_with_hole():
    outer = [(1, 1), (5, 1), (5, 5), (1, 5), (1, 1)]
    hole = [(2, 2), (2, 4), (4, 4), (4, 2), (2, 2)]
    out = rasterize([[outer, hole]], 7, 7)
    assert out[3, 1]
    assert not out[3, 3]


def test_trace_preserves_vertical_position():
    mask = np.zeros((32, 32), dtype=bool)
    mask[2:6, 4:12] = True
    out = vectorize_frame(mask, {"rdp_epsilon": 1.0, "min_segment": 2})
    assert out[3, 5]
    assert not out[28, 5]


def test_trace_simple_shape_and_roundtrip():
    mask = np.zeros((16, 16), dtype=bool)
    mask[4:12, 4:12] = True
    polys = trace(mask, {"rdp_epsilon": 1.0, "min_segment": 2})
    assert len(polys) >= 1
    roundtrip = rasterize(polys, 16, 16)
    assert roundtrip[6, 6]
    assert not roundtrip[0, 0]