import numpy as np

from behavision.geometry import ARCFACE_TEMPLATE, clip_box, iou, umeyama


def test_clip_box_negative_coords():
    assert clip_box((-20, -10, 50, 60), 640, 480) == (0, 0, 50, 60)


def test_clip_box_fully_outside_returns_none():
    assert clip_box((-50, -50, -10, -10), 640, 480) is None


def test_iou_identical_and_disjoint():
    a = (0, 0, 10, 10)
    assert iou(a, a) == 1.0
    assert iou(a, (20, 20, 30, 30)) == 0.0


def test_umeyama_recovers_similarity_transform():
    rng = np.random.default_rng(0)
    src = rng.uniform(0, 100, (5, 2))
    angle, scale, t = 0.3, 1.7, np.array([12.0, -4.0])
    rot = np.array([[np.cos(angle), -np.sin(angle)],
                    [np.sin(angle), np.cos(angle)]])
    dst = scale * src @ rot.T + t
    m = umeyama(src, dst)
    mapped = src @ m[:, :2].T + m[:, 2]
    assert np.allclose(mapped, dst, atol=1e-3)


def test_umeyama_identity_on_template():
    m = umeyama(ARCFACE_TEMPLATE, ARCFACE_TEMPLATE)
    assert np.allclose(m[:, :2], np.eye(2), atol=1e-4)
    assert np.allclose(m[:, 2], 0, atol=1e-3)