"""
A pop-up menu taller than the window can be scrolled without dismissing itself.

`.ctx-menu` is `overflow-y: auto` under a `max-height`, and a playlist's
tracklist expands *inside* it — sixty tracks is three times the panel's height,
so scrolling is the only way to reach most of them. Both ways of scrolling it
closed it instead: the wheel, and dragging its own scrollbar. Reported against
"remove a track", where the menu vanished before a track could be clicked.

`scroll` does not bubble, so the listener that dismisses the menu on a page
scroll is on the capture phase — and capture is equally what made it hear the
panel's own scrolling on the way down.

Measured, not read. `playlist_ui_probe.py` drives the same menu and cannot see
this: it reaches every row with `.click()`, which scrolls nothing at all.

The last two cases are the ones that must keep closing the menu, and they are
why the fix is a filter on the event's origin rather than a removed listener.
"""

import json
import shutil
import subprocess
import sys
from pathlib import Path

import pytest

HARNESS = Path(__file__).parent / "harness" / "menu_scroll_probe.py"


@pytest.fixture(scope="module")
def cases():
    if shutil.which("google-chrome") is None:
        pytest.skip("Chrome is not available")
    proc = subprocess.run([sys.executable, str(HARNESS)],
                          capture_output=True, text=True, timeout=90)
    data = json.loads(proc.stdout)
    assert "error" not in data, f"probe failed: {proc.stdout}{proc.stderr}"
    return {c["case"]: c for c in data["cases"]}


def test_the_fixture_actually_overflows(cases):
    # A menu that fits measures nothing, and would let every assertion below
    # pass with the fix removed.
    c = cases["the panel is scrollable at all"]
    assert c["overflows"], f"60 rows did not overflow the panel: {c}"


def test_the_wheel_scrolls_the_menu_instead_of_closing_it(cases):
    c = cases["scrolled inside the menu"]
    assert c["stillOpen"], "the menu closed when it was scrolled"
    assert c["scrollTop"] == 200, "the menu did not scroll"


def test_dragging_the_menus_own_scrollbar_does_not_close_it(cases):
    c = cases["pressed the menu scrollbar and dragged"]
    assert c["stillOpen"], "pressing the scrollbar closed the menu"
    assert c["scrollTop"] == 400, "the drag did not scroll"


def test_reaching_the_end_does_not_scroll_the_page_behind(cases):
    # Chained to the page, that overscroll *is* a page scroll, and a page
    # scroll closes the menu on purpose — the same symptom by another door.
    assert cases["the panel is scrollable at all"]["overscrollBehaviorY"] == "contain"


def test_a_press_outside_still_closes_it(cases):
    assert cases["pressed outside the menu"]["closed"]


def test_scrolling_the_page_still_closes_it(cases):
    # Not optional: the menu is `position: fixed` and the media grids scroll
    # under a sticky toolbar, so a menu that survives leaves itself pointing at
    # an album that has moved.
    assert cases["scrolled the page underneath"]["closed"]