"""The shipped YAML carries thresholds measured on the deployment site; the
pydantic defaults must not drift away from them (a trimmed config would then
silently re-admit the false positives those values were tuned to reject)."""
import pytest

from behavision.config import (ApiSection, Config, DetectionSection,
                               RecognitionSection, TrackingSection,
                               ensure_api_credentials, load_config)


def test_yaml_matches_code_defaults():
    cfg = load_config()
    for section, model in (("detection", DetectionSection),
                           ("recognition", RecognitionSection),
                           ("tracking", TrackingSection)):
        loaded = getattr(cfg, section)
        defaults = model()
        for name in model.model_fields:
            assert getattr(loaded, name) == getattr(defaults, name), (
                f"{section}.{name} drifted between config/default.yaml "
                f"and config.py")


def test_tuned_thresholds_are_the_defaults():
    cfg = Config()
    assert cfg.detection.score_threshold == 0.82
    assert cfg.recognition.min_enroll_quality == 0.65


def test_loopback_stays_open(tmp_path):
    cfg = Config()
    cfg.app.data_dir = tmp_path
    cfg.api.host = "127.0.0.1"
    auth_on, generated = ensure_api_credentials(cfg)
    assert (auth_on, generated) == (False, False)
    assert not (tmp_path / "api_credentials.txt").exists()


def test_routable_host_never_served_unauthenticated(tmp_path):
    cfg = Config()
    cfg.app.data_dir = tmp_path
    cfg.api.host = "0.0.0.0"
    auth_on, generated = ensure_api_credentials(cfg)
    assert auth_on and generated
    assert cfg.api.username and len(cfg.api.password) >= 16
    assert (tmp_path / "api_credentials.txt").exists()


def test_generated_credentials_are_stable_across_restarts(tmp_path):
    first = Config()
    first.app.data_dir = tmp_path
    first.api.host = "0.0.0.0"
    ensure_api_credentials(first)

    second = Config()
    second.app.data_dir = tmp_path
    second.api.host = "0.0.0.0"
    auth_on, generated = ensure_api_credentials(second)
    assert auth_on and not generated  # reused, not re-minted
    assert second.api.password == first.api.password


def test_configured_credentials_win(tmp_path):
    cfg = Config()
    cfg.app.data_dir = tmp_path
    cfg.api.host = "0.0.0.0"
    cfg.api.username, cfg.api.password = "alice", "s3cret"
    auth_on, generated = ensure_api_credentials(cfg)
    assert (auth_on, generated) == (True, False)
    assert not (tmp_path / "api_credentials.txt").exists()
    assert cfg.api.password == "s3cret"


def test_blank_env_placeholders_do_not_enable_auth():
    """Unset ${ENV} parses as YAML null; auth must not half-enable."""
    cfg = ApiSection(host="0.0.0.0", port=None, username=None, password=None)
    assert cfg.username == "" and cfg.password == ""
    assert cfg.port == 8010
    assert not cfg.auth_enabled


def test_color_order_is_declared_per_model_family():
    """ArcFace/InsightFace exports want RGB, AdaFace wants BGR. Same scaling,
    opposite channel order, and feeding the wrong one raises nothing — it just
    yields off-distribution embeddings. Pin the mapping down."""
    from behavision.recognition import color_order_for
    for name in ("w600k_mbf", "w600k_r50", "arcface", "arcface_int8"):
        assert color_order_for(name) == "RGB", name
    for name in ("adaface_ir18", "adaface_ir50", "adaface_ir101", "AdaFace_IR50"):
        assert color_order_for(name) == "BGR", name


def test_better_models_are_preferred_over_the_fallback():
    from behavision.recognition import MODEL_CANDIDATES
    order = {n: i for i, n in enumerate(MODEL_CANDIDATES)}
    # first that loads wins, so accuracy must come before the 13 MB fallback
    assert order["w600k_r50.onnx"] < order["w600k_mbf.onnx"]
    assert order["adaface_ir50.onnx"] < order["w600k_r50.onnx"]


def test_unloadable_model_falls_through_to_the_next_candidate(tmp_path):
    """The deploy box may not have RAM for the big model. A corrupt/unusable
    file must be skipped, not fatal — otherwise a memory-starved machine can
    no longer start at all."""
    import shutil
    from pathlib import Path

    from behavision.recognition import ArcFaceEncoder

    real = Path(__file__).resolve().parent.parent / "models" / "w600k_mbf.onnx"
    if not real.exists():
        import pytest
        pytest.skip("no recognition model installed")
    # a plausible-looking but unloadable "big model" ahead of a good one
    (tmp_path / "w600k_r50.onnx").write_bytes(b"not an onnx file")
    shutil.copy(real, tmp_path / "w600k_mbf.onnx")
    enc = ArcFaceEncoder(tmp_path)
    assert enc.model_name == "w600k_mbf"  # fell through, did not crash


def test_no_usable_model_fails_loudly(tmp_path):
    from behavision.recognition import ArcFaceEncoder
    (tmp_path / "w600k_mbf.onnx").write_bytes(b"garbage")
    with pytest.raises(FileNotFoundError, match="no usable recognition model"):
        ArcFaceEncoder(tmp_path)