import importlib.util
from pathlib import Path
from unittest.mock import patch

import pytest


PROJECT_ROOT = Path(__file__).resolve().parents[1]
SCRIPT_PATH = PROJECT_ROOT / "tools" / "build_node.py"


def load_launcher():
    specification = importlib.util.spec_from_file_location(
        "node_asset_launcher",
        SCRIPT_PATH,
    )
    module = importlib.util.module_from_spec(specification)
    specification.loader.exec_module(module)
    return module


def test_blender_path_prefers_explicit_path(tmp_path):
    launcher = load_launcher()
    executable = tmp_path / "blender"
    executable.touch()

    with patch.dict("os.environ", {"BLENDER_BIN": "ignored"}):
        assert launcher.blender_path(executable) == executable


def test_blender_path_reads_environment(tmp_path):
    launcher = load_launcher()
    executable = tmp_path / "blender"
    executable.touch()

    with patch.dict("os.environ", {"BLENDER_BIN": str(executable)}):
        assert launcher.blender_path() == executable


def test_blender_path_reads_project_dotenv(tmp_path):
    launcher = load_launcher()
    executable = tmp_path / "Blender 4.5" / "blender.exe"
    executable.parent.mkdir()
    executable.touch()
    env_path = tmp_path / ".env"
    env_path.write_text(
        f'BLENDER_BIN="{executable}"\n',
        encoding="utf-8",
    )

    with patch.dict("os.environ", {}, clear=True), patch.object(
        launcher,
        "PROJECT_ROOT",
        tmp_path,
    ):
        assert launcher.blender_path() == executable


def test_blender_path_reports_missing_configuration(tmp_path):
    launcher = load_launcher()

    with patch.dict("os.environ", {}, clear=True), patch.object(
        launcher.shutil,
        "which",
        return_value=None,
    ), patch.object(
        launcher,
        "PROJECT_ROOT",
        tmp_path,
    ):
        with pytest.raises(RuntimeError, match="Blender not found"):
            launcher.blender_path()