from pathlib import Path
import importlib
import sys

import numpy as np


PROJECT_ROOT = Path(__file__).resolve().parents[1]
if str(PROJECT_ROOT) not in sys.path:
    sys.path.insert(0, str(PROJECT_ROOT))


def test_local_bytetrack_module_is_importable_from_project_root():
    module = importlib.import_module("bytetrack_min_aggressive")

    assert hasattr(module, "BYTETracker")


def test_local_bytetrack_module_file_exists_in_project_root():
    assert (PROJECT_ROOT / "bytetrack_min_aggressive.py").exists()


def test_hungarian_matches_single_pair():
    module = importlib.import_module("bytetrack_min_aggressive")
    assert module.hungarian(np.array([[0.0]], dtype=np.float32)) == [(0, 0)]


def test_bytetrack_keeps_id_for_same_box():
    module = importlib.import_module("bytetrack_min_aggressive")
    tracker = module.BYTETracker(
        track_high_thresh=0.02,
        track_low_thresh=0.01,
        new_track_thresh=0.02,
        match_thresh=0.10,
        min_hits=1,
    )
    det = np.array([[10.0, 10.0, 40.0, 40.0, 0.05]], dtype=np.float32)

    first = tracker.update(det, dt=0.04)
    second = tracker.update(det, dt=0.04)

    assert len(first) == 1
    assert len(second) == 1
    assert second[0].track_id == first[0].track_id
    assert second[0].hits == 2