"""Regression tests for cross-platform helper behavior."""

import importlib.util
from pathlib import Path


_MODULE_PATH = Path(__file__).resolve().parents[1] / "core" / "platform_compat.py"
_SPEC = importlib.util.spec_from_file_location("platform_compat_under_test", _MODULE_PATH)
platform_compat = importlib.util.module_from_spec(_SPEC)
assert _SPEC and _SPEC.loader
_SPEC.loader.exec_module(platform_compat)


def _reset_bash_cache(monkeypatch):
    monkeypatch.setattr(platform_compat, "_BASH_CACHE", None)
    monkeypatch.setattr(platform_compat, "_BASH_PROBED", False)


def test_find_bash_tries_windows_exe_suffix(monkeypatch):
    _reset_bash_cache(monkeypatch)
    monkeypatch.setattr(platform_compat, "IS_WINDOWS", True)

    expected = r"C:\Program Files\Git\bin\bash.exe"

    def fake_which(name):
        return expected if name == "bash.exe" else None

    monkeypatch.setattr(platform_compat.shutil, "which", fake_which)
    monkeypatch.setattr(platform_compat.os.path, "exists", lambda _path: False)

    assert platform_compat.find_bash() == expected


def test_find_bash_checks_local_app_data_git_install(monkeypatch):
    _reset_bash_cache(monkeypatch)
    monkeypatch.setattr(platform_compat, "IS_WINDOWS", True)
    monkeypatch.setattr(platform_compat.shutil, "which", lambda _name: None)
    for env_name in platform_compat._WINDOWS_BASH_ROOT_ENV_VARS:
        monkeypatch.delenv(env_name, raising=False)
    monkeypatch.setenv("LocalAppData", r"C:\Users\alice\AppData\Local")

    expected = r"C:\Users\alice\AppData\Local\Git\bin\bash.exe"
    monkeypatch.setattr(platform_compat.os.path, "exists", lambda path: path == expected)

    assert platform_compat.find_bash() == expected


def test_find_bash_skips_windows_wsl_stub(monkeypatch):
    _reset_bash_cache(monkeypatch)
    monkeypatch.setattr(platform_compat, "IS_WINDOWS", True)

    stub = r"C:\WINDOWS\system32\bash.exe"
    expected = r"C:\Program Files\Git\bin\bash.exe"
    monkeypatch.setattr(
        platform_compat.shutil,
        "which",
        lambda name: stub if name == "bash" else None,
    )
    monkeypatch.setattr(platform_compat.os.path, "exists", lambda path: path == expected)

    assert platform_compat.find_bash() == expected