"""StereoYoloConfig 校验与 JSON 加载测试（需求说明 §4：配置外置、fail-fast）。"""

import json
from pathlib import Path

import pytest

from stereo_yolo import StereoYoloConfig, load_from_json

CONFIG_PATH = Path(__file__).resolve().parents[2] / "config" / "stereo_yolo.json"


def _config_dict() -> dict:
    return json.loads(CONFIG_PATH.read_text(encoding="utf-8"))


def _write(tmp_path: Path, data: dict) -> str:
    path = tmp_path / "stereo_yolo.json"
    path.write_text(json.dumps(data, ensure_ascii=False), encoding="utf-8")
    return str(path)


def test_load_from_json_matches_defaults():
    assert load_from_json(str(CONFIG_PATH)) == StereoYoloConfig()


def test_whitelist_normalized_to_tuple():
    cfg = StereoYoloConfig(class_whitelist=[0, 2])
    assert cfg.class_whitelist == (0, 2)


def test_missing_field_rejected(tmp_path):
    data = _config_dict()
    data.pop("imgsz")
    with pytest.raises(ValueError, match="缺少配置字段"):
        load_from_json(_write(tmp_path, data))


def test_unknown_field_rejected(tmp_path):
    data = _config_dict()
    data["letterbox_scale"] = 0.5
    with pytest.raises(ValueError, match="未知配置字段"):
        load_from_json(_write(tmp_path, data))


@pytest.mark.parametrize(
    "field,value",
    [
        ("model_path", 123),
        ("imgsz", "640"),
        ("imgsz", True),
        ("conf_threshold", "0.25"),
        ("iou_threshold", None),
        ("class_whitelist", 0),
        ("class_whitelist", ["0"]),
        ("device", 5),
        ("concurrency", 1),
    ],
)
def test_type_error_rejected(tmp_path, field, value):
    data = _config_dict()
    data[field] = value
    with pytest.raises(ValueError, match="配置类型非法"):
        load_from_json(_write(tmp_path, data))


@pytest.mark.parametrize(
    "field,value",
    [
        ("model_path", ""),
        ("imgsz", 0),
        ("imgsz", 600),
        ("conf_threshold", -0.1),
        ("conf_threshold", 1.5),
        ("iou_threshold", 0.0),
        ("class_whitelist", []),
        ("class_whitelist", [-1]),
        ("device", "  "),
        ("concurrency", "batch"),
    ],
)
def test_invalid_values_rejected(field, value):
    with pytest.raises(ValueError, match="配置非法"):
        StereoYoloConfig(**{field: value})


def test_boundary_values_accepted():
    cfg = StereoYoloConfig(
        imgsz=32,
        conf_threshold=0.0,
        iou_threshold=1.0,
        class_whitelist=(0,),
        device="cpu",
        concurrency="sequential",
    )
    assert cfg.imgsz == 32