031-flash-card/tests/e2e/test_flash_card_window.py

"""End-to-end tests of the flash card window.

@file test_flash_card_window.py
@brief Builds the real window with Tk and checks it against the wireframe.
"""

import time
import tkinter as tk
from collections.abc import Callable, Iterator, Sequence

import pytest

from flash_card.application.use_cases.study_session import StudySession
from flash_card.constants import (
    BACK_TEXT_COLOR,
    BACKGROUND_COLOR,
    CARD_HEIGHT,
    CARD_WIDTH,
    FLIP_DELAY_MS,
    FRONT_TEXT_COLOR,
    LANGUAGE_FONT,
    WINDOW_PADDING,
    WINDOW_TITLE,
    WORD_FONT,
)
from flash_card.domain.entities.card import Card
from flash_card.domain.entities.deck import Deck
from flash_card.domain.value_objects.language_pair import LanguagePair
from flash_card.presentation.features.flash_card import flash_card_view
from flash_card.presentation.features.flash_card.flash_card_view import FlashCardView
from flash_card.presentation.features.flash_card.flash_card_view_model import (
    FlashCardViewModel,
)

CARDS = (Card("aku", "mig"), Card("kau", "du"), Card("ini", "denne"))


def _first(cards: Sequence[Card]) -> Card:
    return cards[0]


def _build_view(root: tk.Tk) -> FlashCardView:
    deck = Deck(LanguagePair("ms", "da"), CARDS)
    return FlashCardView(root, FlashCardViewModel(StudySession(deck, _first)))


def _shown(view: FlashCardView) -> tuple[str, str]:
    return (
        str(view.canvas.itemcget(view.language_text_id, "text")),
        str(view.canvas.itemcget(view.word_text_id, "text")),
    )


@pytest.fixture(scope="module")
def window() -> Iterator[tuple[tk.Tk, FlashCardView]]:
    # One Tk per module: a second interpreter right after destroying the
    # first fails to find init.tcl on some Windows Python installs.
    try:
        root = tk.Tk()
    except tk.TclError:
        pytest.skip("no display available for Tk")
    view = _build_view(root)
    root.update_idletasks()
    yield root, view
    root.destroy()


def test_window_has_title_background_and_padding(
    window: tuple[tk.Tk, FlashCardView],
) -> None:
    root, _view = window
    assert root.title() == WINDOW_TITLE
    assert root.cget("bg") == BACKGROUND_COLOR
    assert int(str(root.cget("padx"))) == WINDOW_PADDING
    assert int(str(root.cget("pady"))) == WINDOW_PADDING


def test_canvas_has_card_size_and_spans_two_columns(
    window: tuple[tk.Tk, FlashCardView],
) -> None:
    _root, view = window
    assert int(str(view.canvas.cget("width"))) == CARD_WIDTH
    assert int(str(view.canvas.cget("height"))) == CARD_HEIGHT
    info = view.canvas.grid_info()
    assert (int(info["row"]), int(info["column"])) == (0, 0)
    assert int(info["columnspan"]) == 2


def test_canvas_holds_one_image_and_two_texts(
    window: tuple[tk.Tk, FlashCardView],
) -> None:
    _root, view = window
    types = [view.canvas.type(item) for item in view.canvas.find_all()]
    assert types.count("image") == 1
    assert types.count("text") == 2
    assert len(types) == 3


def test_texts_show_first_card_with_font_and_colour(
    window: tuple[tk.Tk, FlashCardView],
) -> None:
    _root, view = window
    canvas = view.canvas
    expected = [
        (view.language_text_id, "Malay", LANGUAGE_FONT),
        (view.word_text_id, "aku", WORD_FONT),
    ]
    for item, text, font in expected:
        assert canvas.itemcget(item, "text") == text
        assert canvas.itemcget(item, "fill") == FRONT_TEXT_COLOR
        family, size, style = font
        assert canvas.itemcget(item, "font").split() == [family, str(size), style]


def test_buttons_sit_in_row_one_with_their_images(
    window: tuple[tk.Tk, FlashCardView],
) -> None:
    _root, view = window
    wrong = view.wrong_button.grid_info()
    right = view.right_button.grid_info()
    assert (int(wrong["row"]), int(wrong["column"])) == (1, 0)
    assert (int(right["row"]), int(right["column"])) == (1, 1)
    wrong_image = str(view.wrong_button.cget("image"))
    right_image = str(view.right_button.cget("image"))
    assert wrong_image
    assert right_image
    assert wrong_image != right_image
    assert str(view.wrong_button.cget("command"))
    assert str(view.right_button.cget("command"))


def test_each_button_press_shows_next_card(
    window: tuple[tk.Tk, FlashCardView],
) -> None:
    _root, view = window
    assert _shown(view) == ("Malay", "aku")
    view.wrong_button.invoke()
    assert _shown(view) == ("Malay", "kau")
    view.right_button.invoke()
    assert _shown(view) == ("Malay", "aku")


def _word(view: FlashCardView) -> str:
    return _shown(view)[1]


def _image(view: FlashCardView) -> str:
    return str(view.canvas.itemcget(view.image_id, "image"))


def _fill(view: FlashCardView) -> tuple[str, str]:
    return (
        str(view.canvas.itemcget(view.language_text_id, "fill")),
        str(view.canvas.itemcget(view.word_text_id, "fill")),
    )


def _reset(root: tk.Tk, view: FlashCardView) -> None:
    """Show a fresh front with no pending timer."""
    view.next_card()
    if view.flip_timer is not None:
        root.after_cancel(view.flip_timer)
        view.flip_timer = None


def test_front_state_uses_front_image_black_text_and_front_language(
    window: tuple[tk.Tk, FlashCardView],
) -> None:
    root, view = window
    _reset(root, view)
    assert _image(view) == str(view.card_front_image)
    assert _fill(view) == (FRONT_TEXT_COLOR, FRONT_TEXT_COLOR)
    assert _shown(view)[0] == "Malay"
    assert _word(view) in {card.front for card in CARDS}


def test_flip_card_shows_back_image_white_text_and_translation(
    window: tuple[tk.Tk, FlashCardView],
) -> None:
    root, view = window
    _reset(root, view)
    front = _word(view)
    view.flip_card()
    translations = {card.front: card.back for card in CARDS}
    assert _image(view) == str(view.card_back_image)
    assert _image(view) != str(view.card_front_image)
    assert _fill(view) == (BACK_TEXT_COLOR, BACK_TEXT_COLOR)
    assert _shown(view) == ("Danish", translations[front])
    assert view.flip_timer is None


def test_next_card_after_flip_shows_front_again(
    window: tuple[tk.Tk, FlashCardView],
) -> None:
    root, view = window
    _reset(root, view)
    view.flip_card()
    view.right_button.invoke()
    assert _image(view) == str(view.card_front_image)
    assert _fill(view) == (FRONT_TEXT_COLOR, FRONT_TEXT_COLOR)
    assert _shown(view)[0] == "Malay"
    _reset(root, view)


def test_next_card_cancels_pending_timer_and_schedules_flip(
    window: tuple[tk.Tk, FlashCardView],
    monkeypatch: pytest.MonkeyPatch,
) -> None:
    root, view = window
    _reset(root, view)
    calls: list[tuple[str, object]] = []

    def fake_after(delay: int, callback: Callable[[], None]) -> str:
        calls.append(("after", (delay, callback)))
        return "timer-id"

    def fake_cancel(timer_id: str) -> None:
        calls.append(("cancel", timer_id))

    monkeypatch.setattr(root, "after", fake_after, raising=False)
    monkeypatch.setattr(root, "after_cancel", fake_cancel, raising=False)
    view.flip_timer = "old-id"
    view.next_card()
    assert calls == [
        ("cancel", "old-id"),
        ("after", (FLIP_DELAY_MS, view.flip_card)),
    ]
    assert view.flip_timer == "timer-id"
    view.flip_timer = None


def test_real_timer_flips_card_after_delay(
    window: tuple[tk.Tk, FlashCardView],
    monkeypatch: pytest.MonkeyPatch,
) -> None:
    root, view = window
    monkeypatch.setattr(flash_card_view, "FLIP_DELAY_MS", 50)
    view.next_card()
    assert _image(view) == str(view.card_front_image)
    deadline = time.monotonic() + 2
    while view.flip_timer is not None and time.monotonic() < deadline:
        root.update()
        time.sleep(0.005)
    assert view.flip_timer is None
    assert _image(view) == str(view.card_back_image)
    assert _shown(view)[0] == "Danish"
    _reset(root, view)