"""GUI tests for the live canvas-backend switch (PyVista ⇄ Plotly).

QSettings are injected per-test so a swap never leaks into the real user
configuration or the next test.
"""

from __future__ import annotations

import pytest

pytest.importorskip("PySide6")
pytest.importorskip("pyvistaqt")
pytest.importorskip("plotly")

from PySide6.QtCore import QSettings


def _make_window(tmp_path, qtbot):  # type: ignore[no-untyped-def]
    from otko.views.main_window import MainWindow

    settings = QSettings(str(tmp_path / "otko.ini"), QSettings.Format.IniFormat)
    window = MainWindow(settings=settings)
    qtbot.addWidget(window)
    return window


@pytest.mark.gui
def test_default_backend_is_pyvista(tmp_path, qtbot) -> None:  # type: ignore[no-untyped-def]
    from otko.views.canvas3d import ModelCanvas

    window = _make_window(tmp_path, qtbot)
    assert window.canvas_backend() == "pyvista"
    assert isinstance(window._canvas, ModelCanvas)
    assert window._diagram_renderer is not None


@pytest.mark.gui
def test_switch_to_plotly_preserves_selection(tmp_path, qtbot) -> None:  # type: ignore[no-untyped-def]
    from otko.views.canvas_plotly import PlotlyCanvas

    window = _make_window(tmp_path, qtbot)
    window._vm.new_project()
    window._canvas.selection.select_node(2)

    window.swap_canvas_backend("plotly")

    assert window.canvas_backend() == "plotly"
    assert isinstance(window._canvas, PlotlyCanvas)
    # One shared SelectionState: the tree/table/properties stay bound.
    assert window._canvas.selection is window._selection
    assert window._canvas.selection.nodes == frozenset({2})
    # Both canvases live in the stack; the PyVista one was not destroyed.
    assert window._canvas_stack.count() == 2


@pytest.mark.gui
def test_plotly_gates_pyvista_only_features(tmp_path, qtbot) -> None:  # type: ignore[no-untyped-def]
    window = _make_window(tmp_path, qtbot)
    assert window._canvas.capabilities.diagrams is True

    window.swap_canvas_backend("plotly")
    caps = window._canvas.capabilities
    assert caps.diagrams is False
    assert caps.animation_export is False
    assert caps.extrusions is True and caps.labels is True

    window._refresh_action_enablement()
    assert window._act_show_force_diagram.isEnabled() is False
    assert window._act_export_th_animation.isEnabled() is False


@pytest.mark.gui
def test_swapping_back_reuses_the_same_canvases(tmp_path, qtbot) -> None:  # type: ignore[no-untyped-def]
    window = _make_window(tmp_path, qtbot)
    pyvista_canvas = window._canvas

    window.swap_canvas_backend("plotly")
    plotly_canvas = window._canvas
    window.swap_canvas_backend("pyvista")

    assert window._canvas is pyvista_canvas
    assert window._diagram_renderer is not None
    # No duplicate widgets accumulate across repeated swaps.
    window.swap_canvas_backend("plotly")
    assert window._canvas is plotly_canvas
    assert window._diagram_renderer is None  # diagrams are PyVista-only
    assert window._canvas_stack.count() == 2


@pytest.mark.gui
def test_backend_choice_is_persisted(tmp_path, qtbot) -> None:  # type: ignore[no-untyped-def]
    window = _make_window(tmp_path, qtbot)
    window.swap_canvas_backend("plotly")
    assert window._settings.value("canvas/backend") == "plotly"

    # A fresh window with the same settings boots straight into Plotly.
    from otko.views.canvas_plotly import PlotlyCanvas
    from otko.views.main_window import MainWindow

    settings = QSettings(str(tmp_path / "otko.ini"), QSettings.Format.IniFormat)
    second = MainWindow(settings=settings)
    qtbot.addWidget(second)
    assert second.canvas_backend() == "plotly"
    assert isinstance(second._canvas, PlotlyCanvas)


@pytest.mark.gui
def test_working_plane_survives_the_swap(tmp_path, qtbot) -> None:  # type: ignore[no-untyped-def]
    window = _make_window(tmp_path, qtbot)
    window._vm.open(_example("basic_truss"))
    window._canvas.set_working_plane("XY", 0.0)

    window.swap_canvas_backend("plotly")

    assert window._canvas.working_plane_type() == "XY"
    assert window._canvas.working_plane_offset() == 0.0


def _example(name: str) -> str:
    from pathlib import Path

    return str(Path(__file__).resolve().parents[2] / "examples" / f"{name}.osmodel")