from __future__ import annotations

import pytest

from dovla_cil.sim import genesis_backend, maniskill_backend
from dovla_cil.sim.registry import create_backend, get_backend_class, list_backends
from dovla_cil.sim.toy_backend import ToyBackend


def test_registry_can_list_optional_backends() -> None:
    backends = list_backends()

    assert "toy" in backends
    assert "maniskill" in backends
    assert "genesis" in backends


def test_maniskill_backend_class_imports_without_dependency() -> None:
    backend_class = get_backend_class("maniskill")

    assert backend_class.__name__ == "ManiSkillBackend"


def test_genesis_backend_class_imports_without_dependency() -> None:
    backend_class = get_backend_class("genesis")

    assert backend_class.__name__ == "GenesisBackend"


def test_requesting_maniskill_without_dependency_gives_clean_error(
    monkeypatch: pytest.MonkeyPatch,
) -> None:
    monkeypatch.setattr(maniskill_backend, "_find_maniskill_module", lambda: None)

    with pytest.raises(ImportError) as exc_info:
        create_backend("maniskill")

    message = str(exc_info.value)
    assert "Install optional dependency with" in message
    assert "OPENCLAUDE" not in message


def test_requesting_genesis_without_dependency_gives_clean_error(
    monkeypatch: pytest.MonkeyPatch,
) -> None:
    monkeypatch.setattr(genesis_backend, "_find_genesis_module", lambda: None)

    with pytest.raises(ImportError) as exc_info:
        create_backend("genesis")

    message = str(exc_info.value)
    assert "Install optional dependency with" in message
    assert "OPENCLAUDE" not in message


def test_unknown_backend_raises_value_error() -> None:
    with pytest.raises(ValueError):
        create_backend("unknown")


def test_toy_backend_unaffected() -> None:
    assert isinstance(create_backend("toy"), ToyBackend)