import importlib.util
import unittest
from pathlib import Path


PROJECT_ROOT = Path(__file__).resolve().parents[1]


def load_module(name, relative_path):
    specification = importlib.util.spec_from_file_location(
        name,
        PROJECT_ROOT / relative_path,
    )
    module = importlib.util.module_from_spec(specification)
    specification.loader.exec_module(module)
    return module


class ModelTest(unittest.TestCase):
    @classmethod
    def setUpClass(cls):
        cls.models = load_module(
            "snapform_models",
            "src/snapform/models.py",
        )

    def test_base_model_is_default_friendly_apache_model(self):
        model = self.models.get_model("BASE")

        self.assertEqual(model.repository, "depth-anything/DA3-BASE")
        self.assertEqual(model.license_name, "Apache 2.0")

    def test_large_model_exposes_noncommercial_license(self):
        model = self.models.get_model("LARGE_1_1")

        self.assertEqual(model.license_name, "CC BY-NC 4.0")

    def test_giant_models_expose_gaussian_head(self):
        for model_key in ("GIANT_1_1", "NESTED_GIANT_LARGE_1_1"):
            with self.subTest(model_key=model_key):
                self.assertTrue(self.models.get_model(model_key).supports_gs)

    def test_unknown_model_is_rejected(self):
        with self.assertRaisesRegex(ValueError, "Unknown DA3 model"):
            self.models.get_model("UNKNOWN")