"""
Hidden axis labels (stored, not drawn)
=========================================

``set_xlabel("...", visible=False)`` / ``set_ylabel(..., visible=False)``
-- or ``set_xlabel_visible(False)`` / ``set_ylabel_visible(False)`` to
toggle without retyping the text -- store an axis label without drawing
it and without reserving any margin for it. ``get_xlabel()`` still
returns the text, ``ax.print_summary()`` still lists it (marked
``(hidden)``), the ``load_data()`` layout round-trip still carries it,
and a picked point's **Extract** record in the interactive HTML still
reports it (see :doc:`/user_guide/interactivity` for what an Extract
record contains).

The use for it: a dense grid where a per-panel label on every axes would
be clutter, so the figure shows one shared
:meth:`~plotpress.figure.Figure.supxlabel`/
:meth:`~plotpress.figure.Figure.supylabel` instead -- but each panel's
axes should still *know* what its x and y mean, for anyone who later
pulls the data back out. See
:doc:`/auto_examples/data_roundtrip/plot_07_hidden_labels_survive_the_roundtrip`
for that payoff, with a worked Extract record.
"""
import numpy as np
import plotpress

rng = np.random.default_rng(2)
t = np.linspace(0, 8, 200)

fig, axes = plotpress.subplots(3, 3, figsize=(8, 7))
for i, ax in enumerate(axes.ravel()):
    ax.plot(t, np.sin(t + i) + 0.1 * rng.standard_normal(t.size))
    # Every panel names its own axes -- but hidden, so the grid stays clean
    # and only the shared labels below are actually drawn.
    ax.set_xlabel("elapsed time (s)", visible=False)
    ax.set_ylabel("signal (mV)", visible=False)

fig.supxlabel("elapsed time (s)")
fig.supylabel("signal (mV)")
fig.suptitle("9 channels: per-panel labels hidden, one shared pair drawn")
fig.tight_layout()

# The text is still there -- just not painted.
mid = axes[1, 1]
print("get_xlabel() still returns:", repr(mid.get_xlabel()))
print("get_xlabel_visible():", mid.get_xlabel_visible())

# set_xlabel_visible() / set_ylabel_visible() flip the state without
# retyping the label -- toggle one on to inspect it, then back off.
mid.set_xlabel_visible(True)
assert mid.get_xlabel_visible() is True
mid.set_xlabel_visible(False)
assert not mid.get_xlabel_visible() and mid.get_xlabel() == "elapsed time (s)"

# print_summary() marks a hidden label so it's obvious which panels carry
# one that isn't on the canvas.
axes[2, 2].print_summary()