"""Viewport orientation triad is present and survives every re-render path.

Before this change the 3D viewport had no X/Y/Z corner marker — users
who rotated the camera off the default isometric view lost track of
which world axis was which. The triad is now built once during the
canvas's scene-furniture setup and lives in screen-space via PyVista's
``vtkOrientationMarkerWidget``, so it is not affected by the regular
actor rebuilds in :meth:`ModelRenderer.render` /
:meth:`ModelRenderer._teardown_all`.

These tests pin the contract:

- Triad exists right after ``MainWindow`` construction.
- It still exists after a tree refresh (which calls
  ``ModelRenderer.render`` through ``MainWindow._on_project_changed``).
- It still exists after loading an empty project, then a small project
  with a node — the most common real-world re-render path.
- The triad carries the conventional X / Y / Z labels.
- It is pinned to the lower-left viewport corner.
"""

from __future__ import annotations

import pytest

pytest.importorskip("PySide6")

from otko.core import Node


@pytest.mark.gui
def test_axes_widget_exists_after_window_construction(qtbot) -> None:  # type: ignore[no-untyped-def]
    from otko.views.main_window import MainWindow

    mw = MainWindow()
    qtbot.addWidget(mw)
    aw = mw._canvas.renderer.axes_widget
    assert aw is not None
    # PyVista binds a vtkOrientationMarkerWidget; the orientation marker
    # it carries is a vtkAxesActor with X/Y/Z label text.
    actor = aw.GetOrientationMarker()
    assert actor.GetXAxisLabelText() == "X"
    assert actor.GetYAxisLabelText() == "Y"
    assert actor.GetZAxisLabelText() == "Z"
    # Pinned to the lower-left viewport patch (normalized 0..1 coords).
    vp = aw.GetViewport()
    assert vp[0] == pytest.approx(0.0)
    assert vp[1] == pytest.approx(0.0)


@pytest.mark.gui
def test_axes_widget_survives_tree_refresh(qtbot) -> None:  # type: ignore[no-untyped-def]
    """``MainWindow._refresh_tree`` triggers a renderer rebuild via
    ``_on_project_changed``; the orientation widget must stay put."""
    from otko.views.main_window import MainWindow

    mw = MainWindow()
    qtbot.addWidget(mw)
    aw_before = mw._canvas.renderer.axes_widget

    mw._vm.new_project(ndm=3, ndf=6)
    mw._vm.project.nodes.extend(
        [
            Node(id=1, coords=(0, 0, 0)),
            Node(id=2, coords=(3, 0, 0)),
        ]
    )
    mw._refresh_tree(mw._vm.project)

    aw_after = mw._canvas.renderer.axes_widget
    # Same widget instance — proves the marker survived the rebuild.
    assert aw_after is aw_before
    actor = aw_after.GetOrientationMarker()
    assert actor.GetXAxisLabelText() == "X"
    assert actor.GetYAxisLabelText() == "Y"
    assert actor.GetZAxisLabelText() == "Z"


@pytest.mark.gui
def test_axes_widget_survives_empty_then_loaded_project(qtbot) -> None:  # type: ignore[no-untyped-def]
    """The two re-render paths the engineer hits during a session:
    empty project → first node added → tree refreshed. The triad must
    still be in the lower-left corner with all three labels."""
    from otko.views.main_window import MainWindow

    mw = MainWindow()
    qtbot.addWidget(mw)
    aw_before = mw._canvas.renderer.axes_widget
    assert aw_before is not None

    # Empty project — model renderer builds no actors, just the grid.
    mw._vm.new_project(ndm=3, ndf=6)
    mw._refresh_tree(mw._vm.project)
    assert mw._canvas.renderer.axes_widget is aw_before

    # Small project with one node — exercises the node-actor rebuild path.
    mw._vm.project.nodes.append(Node(id=1, coords=(1, 2, 3)))
    mw._refresh_tree(mw._vm.project)
    assert mw._canvas.renderer.axes_widget is aw_before

    # Same after a full canvas refresh too — show_project rebuilds actors.
    mw._canvas.show_project(mw._vm.project)
    assert mw._canvas.renderer.axes_widget is aw_before
    actor = mw._canvas.renderer.axes_widget.GetOrientationMarker()
    assert actor.GetXAxisLabelText() == "X"
    assert actor.GetYAxisLabelText() == "Y"
    assert actor.GetZAxisLabelText() == "Z"