"""Smoke tests for LineCrossCounter (src/counting.py). Pure-Python: needs only numpy."""

from src.counting import LineCrossCounter
from src.interfaces import Detection


def _det(tid, y1, cx=500.0):
    return Detection(
        bbox=(cx - 20, y1, cx + 20, y1 + 60),
        confidence=0.9,
        class_id=0,
        class_name="sack",
        track_id=tid,
    )


def _counter():
    return LineCrossCounter(line_y=100, line_x_start=0, line_x_end=1000, margin=20)


def test_loading_above_then_below():
    c = _counter()
    assert c.update([_det(1, y1=10)]) == []          # above line
    events = c.update([_det(1, y1=150)])             # below line
    assert len(events) == 1
    assert events[0]["direction"] == "loading"
    assert c.loading_count == 1


def test_below_first_counts_as_unloading_not_loading():
    c = _counter()
    assert c.update([_det(2, y1=150)]) == []         # appeared below first
    assert c.update([_det(2, y1=10)]) != []          # moved above => unloading
    assert c.unloading_count == 1
    assert c.loading_count == 0


def test_track_counted_once_per_direction():
    c = _counter()
    c.update([_det(3, y1=10)])
    c.update([_det(3, y1=150)])
    c.update([_det(3, y1=10)])
    c.update([_det(3, y1=150)])
    assert c.loading_count == 1  # track_id counted once for loading


def test_outside_x_bounds_skipped():
    c = _counter()
    c.update([_det(4, y1=10, cx=500.0)])
    assert c.update([_det(4, y1=150, cx=5000.0)]) == []
    assert c.loading_count == 0


def test_net_and_reset():
    c = _counter()
    c.update([_det(5, y1=10)])
    c.update([_det(5, y1=150)])
    assert c.net_count == 1
    c.reset()
    assert (c.loading_count, c.unloading_count, c.net_count) == (0, 0, 0)