"""Round 21: transport buttons fill their bubble as equal tap targets.

The prev/play/next FlashButtons used to hug their ~20px icons in the middle
of the 62px-tall rounded box, leaving most of the bubble unclickable. Now
_box(split=True) tiles the bubble interior with the buttons: each gets an
equal third, expands vertically to the margins, and keeps its glyph centered.
The bubble itself keeps its pre-split footprint (no bigger, no smaller).
"""

from unittest.mock import MagicMock, patch

from lintunes.models import Library, Track
from lintunes.library_manager import LibraryManager
from lintunes.preferences import Preferences
from lintunes import player as player_module
from lintunes.player import Player
from lintunes.gui.transport import TransportBar, CONTROL_HEIGHT


def _mock_player():
    """A real Player with the Qt multimedia backend stubbed out (it blocks on
    init headless — see tests/test_player.py)."""
    library = Library(tracks={1: Track(track_id=1, name="One")})
    with patch.multiple(
        player_module,
        QMediaPlayer=MagicMock(),
        QAudioOutput=MagicMock(),
        QAudioBufferOutput=MagicMock(),
        QMediaDevices=MagicMock(),
    ):
        return Player(MagicMock(library=library))


def _build_bar(qapp, tmp_path):
    prefs = Preferences(tmp_path)
    manager = LibraryManager(
        Library(tracks={1: Track(track_id=1, name="One")}), tmp_path)
    bar = TransportBar(_mock_player(), manager, prefs)
    bar.resize(1200, 90)
    bar.show()
    qapp.processEvents()
    return bar


class TestTransportTapTargets:
    def test_buttons_split_the_bubble_equally(self, qapp, tmp_path):
        bar = _build_bar(qapp, tmp_path)
        widths = [b.width() for b in
                  (bar._prev_btn, bar._play_btn, bar._next_btn)]
        assert max(widths) - min(widths) <= 1

    def test_buttons_fill_the_bubble_vertically(self, qapp, tmp_path):
        bar = _build_bar(qapp, tmp_path)
        for btn in (bar._prev_btn, bar._play_btn, bar._next_btn,
                    bar._shuffle_btn):
            # Bubble height minus margins+border (4px each side).
            assert btn.height() >= CONTROL_HEIGHT - 10

    def test_buttons_span_the_bubble_horizontally(self, qapp, tmp_path):
        bar = _build_bar(qapp, tmp_path)
        box = bar._prev_btn.parentWidget()
        assert bar._prev_btn.x() <= 5  # flush against the left margin
        right_edge = bar._next_btn.x() + bar._next_btn.width()
        assert right_edge >= box.width() - 5  # ...and the right one
        # No stretch gaps between the buttons.
        assert bar._play_btn.x() == bar._prev_btn.x() + bar._prev_btn.width()
        assert bar._next_btn.x() == bar._play_btn.x() + bar._play_btn.width()

    def test_bubble_keeps_its_footprint(self, qapp, tmp_path):
        """The bubble must not grow (trav's constraint) nor shrink (the
        minimum button widths preserve the old stretch-padded size)."""
        bar = _build_bar(qapp, tmp_path)
        box = bar._prev_btn.parentWidget()
        assert box.height() == CONTROL_HEIGHT
        assert 106 <= box.width() <= 126  # was 116 pre-split