"""Shared pytest configuration.

The GUI suite is headless by default: unless the caller already chose a
platform, ``QT_QPA_PLATFORM=offscreen`` is set here, before pytest-qt
builds its session ``QApplication``. An explicit caller value is respected.

OpenseesPy is a process-global singleton, so a lazy autouse guard wipes the
domain after every test. The import is inside the teardown so that
``tests/unit`` never imports the solver.
"""

from __future__ import annotations

import importlib.util
import os
from collections.abc import Iterator

import pytest

os.environ.setdefault("QT_QPA_PLATFORM", "offscreen")


@pytest.fixture(autouse=True, scope="session")
def _isolate_qsettings(tmp_path_factory: pytest.TempPathFactory) -> Iterator[None]:
    """Redirect ``QSettings`` to a temp dir so tests never touch user state.

    ``MainWindow`` persists preferences (window layout, canvas backend) under
    ``QSettings("OTKO", "OTKO")``. Without redirection a developer who, say,
    switched to the Plotly backend would see PyVista-specific GUI tests fail
    against their real settings. Skipped entirely when Qt is not installed, so
    the headless job stays free of Qt.
    """
    if importlib.util.find_spec("PySide6") is None:
        yield
        return
    from PySide6.QtCore import QSettings

    settings_dir = tmp_path_factory.mktemp("qsettings")
    for fmt in (QSettings.Format.NativeFormat, QSettings.Format.IniFormat):
        QSettings.setPath(fmt, QSettings.Scope.UserScope, str(settings_dir))
    yield


@pytest.fixture(autouse=True)
def _wipe_opensees_domain() -> Iterator[None]:
    """Wipe the OpenseesPy domain after a test if the solver was imported."""
    yield
    try:
        from openseespy.opensees import wipe
    except Exception:  # pragma: no cover - solver not installed / import side effects
        return
    wipe()