import sys
from argparse import Namespace
from types import SimpleNamespace

_inserted_numpy_stub = "numpy" not in sys.modules
if _inserted_numpy_stub:
    sys.modules["numpy"] = SimpleNamespace(ndarray=object)

from src.config_loader import TrackerSettings
from src.tracker import PersonTracker

if _inserted_numpy_stub:
    sys.modules.pop("numpy", None)


def settings() -> TrackerSettings:
    return TrackerSettings(False, "bytetrack", .5, .1, .6, .8, 30, 2, 30, True)


def test_external_rows_are_normalized_and_ids_are_stable() -> None:
    tracker = PersonTracker(settings())
    rows = [[-2, 1, 20, 30, 7, .9, 0, 0]]
    first = tracker._normalize(rows, 100, 100)
    second = tracker._normalize(rows, 100, 100)
    assert first[0].track_id == second[0].track_id
    assert first[0].bbox.x1 == 0
    assert not first[0].is_confirmed
    assert second[0].is_confirmed


def test_empty_non_person_and_invalid_boxes_are_filtered() -> None:
    tracker = PersonTracker(settings())
    assert tracker._normalize([], 100, 100) == []
    rows = [[1, 1, 1, 20, 1, .9, 0, 0], [1, 1, 20, 20, 2, .9, 3, 0]]
    assert tracker._normalize(rows, 100, 100) == []


def test_reset_does_not_reuse_public_ids() -> None:
    tracker = PersonTracker(settings())
    first = tracker._normalize([[1, 1, 20, 20, 1, .9, 0, 0]], 100, 100)[0].track_id
    tracker.reset()
    second = tracker._normalize([[1, 1, 20, 20, 1, .9, 0, 0]], 100, 100)[0].track_id
    assert second > first


def test_backend_constructor_supports_new_and_old_ultralytics_apis() -> None:
    class NewBackend:
        def __init__(self, args: Namespace) -> None:
            self.args = args

    class OldBackend:
        def __init__(self, args: Namespace, frame_rate: int) -> None:
            self.args, self.frame_rate = args, frame_rate

    args = Namespace(track_buffer=30)
    assert PersonTracker._create_backend(NewBackend, args, 25).args is args
    old = PersonTracker._create_backend(OldBackend, args, 25)
    assert old.args is args and old.frame_rate == 25