MIL-005: Step 4 - Save progress

Review record RC-027 (Go, autonomous mode, not independent).

Task: MIL-005#1
Task: MIL-005#2
Task: MIL-005#3
Task: MIL-005#4
Task: MIL-005#5

tests/e2e/test_flash_card_window.py

@@ -7,15 +7,18 @@
 import time
 import tkinter as tk
 from collections.abc import Callable, Iterator, Sequence
+from pathlib import Path
 
 import pytest
 
+from flash_card.application.use_cases.open_study_session import open_study_session
 from flash_card.application.use_cases.study_session import StudySession
 from flash_card.constants import (
     BACK_TEXT_COLOR,
     BACKGROUND_COLOR,
     CARD_HEIGHT,
     CARD_WIDTH,
+    FINISHED_MESSAGE,
     FLIP_DELAY_MS,
     FRONT_TEXT_COLOR,
     LANGUAGE_FONT,
@@ -26,6 +29,12 @@ from flash_card.constants import (
 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.infrastructure.persistence.csv_progress_repository import (
+    CsvProgressRepository,
+)
+from flash_card.infrastructure.persistence.csv_vocabulary_repository import (
+    CsvVocabularyRepository,
+)
 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 (
@@ -39,9 +48,20 @@ def _first(cards: Sequence[Card]) -> Card:
     return cards[0]
 
 
+class _MemoryProgress:
+    """Progress store that keeps nothing: the shared window never deletes cards."""
+
+    def load(self) -> Deck | None:
+        return None
+
+    def save(self, deck: Deck) -> None:
+        return None
+
+
 def _build_view(root: tk.Tk) -> FlashCardView:
     deck = Deck(LanguagePair("ms", "da"), CARDS)
-    return FlashCardView(root, FlashCardViewModel(StudySession(deck, _first)))
+    session = StudySession(deck, _first, _MemoryProgress())
+    return FlashCardView(root, FlashCardViewModel(session))
 
 
 def _shown(view: FlashCardView) -> tuple[str, str]:
@@ -129,14 +149,14 @@ def test_buttons_sit_in_row_one_with_their_images(
     assert str(view.right_button.cget("command"))
 
 
-def test_each_button_press_shows_next_card(
+def test_wrong_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()
+    view.wrong_button.invoke()
     assert _shown(view) == ("Malay", "aku")
 
 
@@ -195,7 +215,7 @@ def test_next_card_after_flip_shows_front_again(
     root, view = window
     _reset(root, view)
     view.flip_card()
-    view.right_button.invoke()
+    view.wrong_button.invoke()
     assert _image(view) == str(view.card_front_image)
     assert _fill(view) == (FRONT_TEXT_COLOR, FRONT_TEXT_COLOR)
     assert _shown(view)[0] == "Malay"
@@ -245,3 +265,65 @@ def test_real_timer_flips_card_after_delay(
     assert _image(view) == str(view.card_back_image)
     assert _shown(view)[0] == "Danish"
     _reset(root, view)
+
+
+HEADER_ONLY = "ms;da\n"
+
+
+@pytest.fixture
+def files_view(
+    window: tuple[tk.Tk, FlashCardView], tmp_path: Path
+) -> Iterator[tuple[FlashCardView, Path]]:
+    """A second view on the shared root, over real repositories in tmp_path."""
+    root, _shared = window
+    words = tmp_path / "words.csv"
+    words.write_text("ms;da\naku;mig\nkau;du\nini;denne\n", encoding="utf-8")
+    progress = tmp_path / "words_to_learn.csv"
+    session = open_study_session(
+        CsvVocabularyRepository(words), CsvProgressRepository(progress), _first
+    )
+    view = FlashCardView(root, FlashCardViewModel(session))
+    yield view, progress
+    if view.flip_timer is not None:
+        root.after_cancel(view.flip_timer)
+    for widget in (view.canvas, view.wrong_button, view.right_button):
+        widget.destroy()
+
+
+def _saved(progress: Path) -> str:
+    return progress.read_bytes().decode("utf-8-sig")
+
+
+def test_right_button_removes_card_and_writes_progress_file(
+    files_view: tuple[FlashCardView, Path],
+) -> None:
+    view, progress = files_view
+    assert _shown(view) == ("Malay", "aku")
+    view.right_button.invoke()
+    assert _shown(view) == ("Malay", "kau")
+    assert _saved(progress) == "ms;da\nkau;du\nini;denne\n"
+
+
+def test_wrong_button_shows_next_card_and_leaves_progress_file_absent(
+    files_view: tuple[FlashCardView, Path],
+) -> None:
+    view, progress = files_view
+    view.wrong_button.invoke()
+    assert _shown(view) == ("Malay", "kau")
+    assert not progress.exists()
+
+
+def test_buttons_do_nothing_visible_when_finished(
+    files_view: tuple[FlashCardView, Path],
+) -> None:
+    view, progress = files_view
+    for _ in range(3):
+        view.right_button.invoke()
+    assert _shown(view) == ("", FINISHED_MESSAGE)
+    assert view.flip_timer is None
+    assert _saved(progress) == HEADER_ONLY
+    view.right_button.invoke()
+    view.wrong_button.invoke()
+    assert _shown(view) == ("", FINISHED_MESSAGE)
+    assert view.flip_timer is None
+    assert _saved(progress) == HEADER_ONLY

tests/integration/test_progress_file.py

@@ -0,0 +1,96 @@
+"""Integration tests of saving and resuming progress over real CSV files."""
+
+from collections.abc import Callable, Sequence
+from pathlib import Path
+
+from flash_card.application.use_cases.open_study_session import open_study_session
+from flash_card.application.use_cases.study_session import StudySession
+from flash_card.domain.entities.card import Card
+from flash_card.infrastructure.persistence.csv_progress_repository import (
+    CsvProgressRepository,
+)
+from flash_card.infrastructure.persistence.csv_vocabulary_repository import (
+    CsvVocabularyRepository,
+)
+
+WORDS = "fr;en\nchaque;each\nparlé;speak\narrivé;come\n"
+
+Choose = Callable[[Sequence[Card]], Card]
+
+
+def _first(cards: Sequence[Card]) -> Card:
+    return cards[0]
+
+
+def _choose_front(front: str) -> Choose:
+    def choose(cards: Sequence[Card]) -> Card:
+        return next(card for card in cards if card.front == front)
+
+    return choose
+
+
+def _open(folder: Path, choose: Choose = _first) -> StudySession:
+    return open_study_session(
+        CsvVocabularyRepository(folder / "words.csv"),
+        CsvProgressRepository(folder / "words_to_learn.csv"),
+        choose,
+    )
+
+
+def _setup(folder: Path) -> Path:
+    (folder / "words.csv").write_text(WORDS, encoding="utf-8")
+    return folder / "words_to_learn.csv"
+
+
+def _text(path: Path) -> str:
+    return path.read_bytes().decode("utf-8-sig")
+
+
+def test_mark_known_writes_remaining_cards_in_order(tmp_path: Path) -> None:
+    progress = _setup(tmp_path)
+    session = _open(tmp_path, _choose_front("parlé"))
+    session.next_card()
+    session.mark_known()
+    assert _text(progress) == "fr;en\nchaque;each\narrivé;come\n"
+
+
+def test_restart_draws_only_from_progress_file(tmp_path: Path) -> None:
+    _setup(tmp_path)
+    first = _open(tmp_path, _choose_front("parlé"))
+    first.next_card()
+    first.mark_known()
+
+    second = _open(tmp_path)
+    fronts: set[str] = set()
+    for _ in range(6):
+        card = second.next_card()
+        assert card is not None
+        fronts.add(card.front_text)
+
+    assert second.remaining == 2
+    assert fronts == {"chaque", "arrivé"}
+
+
+def test_progress_file_is_readable_as_vocabulary(tmp_path: Path) -> None:
+    progress = _setup(tmp_path)
+    session = _open(tmp_path, _choose_front("chaque"))
+    session.next_card()
+    session.mark_known()
+    vocabulary = CsvVocabularyRepository(progress).load()
+    assert vocabulary.cards == (Card("parlé", "speak"), Card("arrivé", "come"))
+
+
+def test_header_only_progress_file_gives_finished_session(tmp_path: Path) -> None:
+    progress = _setup(tmp_path)
+    progress.write_text("fr;en\n", encoding="utf-8")
+    session = _open(tmp_path)
+    assert session.remaining == 0
+    assert session.next_card() is None
+
+
+def test_unknown_card_never_creates_progress_file(tmp_path: Path) -> None:
+    progress = _setup(tmp_path)
+    session = _open(tmp_path)
+    session.next_card()
+    session.next_card()
+    assert not progress.exists()

tests/integration/test_vocabulary_file.py

@@ -1,9 +1,18 @@
 """Integration tests of the word list reader on the delivered file."""
 
+from pathlib import Path
+
 from flash_card.application.use_cases.open_study_session import open_study_session
-from flash_card.constants import DEFAULT_DATA_DIR, VOCABULARY_FILE_NAME
+from flash_card.constants import (
+    DEFAULT_DATA_DIR,
+    PROGRESS_FILE_NAME,
+    VOCABULARY_FILE_NAME,
+)
 from flash_card.domain.entities.card import Card
 from flash_card.domain.value_objects.language_pair import LanguagePair
+from flash_card.infrastructure.persistence.csv_progress_repository import (
+    CsvProgressRepository,
+)
 from flash_card.infrastructure.persistence.csv_vocabulary_repository import (
     CsvVocabularyRepository,
 )
@@ -19,10 +28,11 @@ def test_read_word_list_reads_real_file() -> None:
     assert cards[0] == Card("aku", "mig")
 
 
-def test_open_study_session_yields_card_from_real_file() -> None:
+def test_open_study_session_yields_card_from_real_file(tmp_path: Path) -> None:
     repository = CsvVocabularyRepository(PATH)
     cards = repository.load().cards
-    session = open_study_session(repository, lambda candidates: candidates[0])
+    progress = CsvProgressRepository(tmp_path / PROGRESS_FILE_NAME)
+    session = open_study_session(repository, progress, lambda candidates: candidates[0])
 
     card = session.next_card()
 

tests/unit/application/test_open_study_session.py

@@ -7,6 +7,7 @@ import pytest
 from flash_card.application.dto.card_dto import CardDto
 from flash_card.application.use_cases.open_study_session import open_study_session
 from flash_card.domain.entities.card import Card
+from flash_card.domain.entities.deck import Deck
 from flash_card.domain.entities.vocabulary import Vocabulary
 from flash_card.domain.errors.vocabulary_errors import VocabularyNotFoundError
 from flash_card.domain.value_objects.language_pair import LanguagePair
@@ -20,6 +21,18 @@ class _FakeRepository:
         return self._vocabulary
 
 
+class _RecordingProgress:
+    def __init__(self, stored: Deck | None = None) -> None:
+        self.stored = stored
+        self.saved: list[tuple[Card, ...]] = []
+
+    def load(self) -> Deck | None:
+        return self.stored
+
+    def save(self, deck: Deck) -> None:
+        self.saved.append(deck.cards)
+
+
 class _MissingRepository:
     def load(self) -> Vocabulary:
         raise VocabularyNotFoundError("missing")
@@ -33,7 +46,7 @@ def test_open_study_session_builds_session_over_all_cards() -> None:
     cards = (Card("aku", "mig"), Card("kau", "du"))
     repository = _FakeRepository(Vocabulary(LanguagePair("ms", "da"), cards))
 
-    session = open_study_session(repository, _first)
+    session = open_study_session(repository, _RecordingProgress(), _first)
 
     assert session.remaining == 2
     assert session.next_card() == CardDto("aku", "mig", "ms", "da")
@@ -41,4 +54,33 @@ def test_open_study_session_builds_session_over_all_cards() -> None:
 
 def test_open_study_session_propagates_repository_error() -> None:
     with pytest.raises(VocabularyNotFoundError):
-        open_study_session(_MissingRepository(), _first)
+        open_study_session(_MissingRepository(), _RecordingProgress(), _first)
+
+
+def test_open_study_session_prefers_saved_progress() -> None:
+    pair = LanguagePair("ms", "da")
+    vocabulary = Vocabulary(pair, (Card("aku", "mig"), Card("kau", "du")))
+    progress = _RecordingProgress(Deck(pair, [Card("kau", "du")]))
+
+    session = open_study_session(_FakeRepository(vocabulary), progress, _first)
+
+    assert session.remaining == 1
+    assert session.next_card() == CardDto("kau", "du", "ms", "da")
+
+
+def test_open_study_session_skips_vocabulary_when_progress_exists() -> None:
+    progress = _RecordingProgress(Deck(LanguagePair("ms", "da"), []))
+
+    session = open_study_session(_MissingRepository(), progress, _first)
+
+    assert session.remaining == 0
+
+
+def test_open_study_session_never_saves_on_start() -> None:
+    vocabulary = Vocabulary(LanguagePair("ms", "da"), (Card("aku", "mig"),))
+    progress = _RecordingProgress()
+
+    session = open_study_session(_FakeRepository(vocabulary), progress, _first)
+    session.next_card()
+
+    assert progress.saved == []

tests/unit/application/test_study_session.py

@@ -17,8 +17,20 @@ def _first(cards: Sequence[Card]) -> Card:
     return cards[0]
 
 
-def _session(*cards: Card) -> StudySession:
-    return StudySession(Deck(PAIR, cards), _first)
+class _RecordingProgress:
+    def __init__(self) -> None:
+        self.saved: list[tuple[Card, ...]] = []
+
+    def load(self) -> Deck | None:
+        return None
+
+    def save(self, deck: Deck) -> None:
+        self.saved.append(deck.cards)
+
+
+def _session(*cards: Card, progress: _RecordingProgress | None = None) -> StudySession:
+    store = _RecordingProgress() if progress is None else progress
+    return StudySession(Deck(PAIR, cards), _first, store)
 
 
 def test_current_card_is_none_before_first_draw() -> None:
@@ -58,3 +70,38 @@ def test_remaining_counts_cards_in_deck() -> None:
     session = _session(A, B)
     session.next_card()
     assert session.remaining == 2
+
+
+def test_mark_known_removes_current_card_and_saves_remaining_once() -> None:
+    progress = _RecordingProgress()
+    session = _session(A, B, progress=progress)
+    session.next_card()
+    session.mark_known()
+    assert session.remaining == 1
+    assert session.current_card is None
+    assert progress.saved == [(B,)]
+
+
+def test_mark_known_saves_nothing_when_no_current_card() -> None:
+    progress = _RecordingProgress()
+    session = _session(A, progress=progress)
+    session.mark_known()
+    assert session.remaining == 1
+    assert progress.saved == []
+
+
+def test_mark_known_on_last_card_leaves_session_finished() -> None:
+    progress = _RecordingProgress()
+    session = _session(A, progress=progress)
+    session.next_card()
+    session.mark_known()
+    assert progress.saved == [()]
+    assert session.next_card() is None
+
+
+def test_next_card_never_saves() -> None:
+    progress = _RecordingProgress()
+    session = _session(A, B, progress=progress)
+    session.next_card()
+    session.next_card()
+    assert progress.saved == []

tests/unit/infrastructure/test_csv_progress_repository.py

@@ -0,0 +1,112 @@
+"""Tests of write_word_list and CsvProgressRepository."""
+
+from pathlib import Path
+
+import pytest
+
+from flash_card.domain.entities.card import Card
+from flash_card.domain.entities.deck import Deck
+from flash_card.domain.errors.vocabulary_errors import VocabularyFormatError
+from flash_card.domain.value_objects.language_pair import LanguagePair
+from flash_card.infrastructure.persistence.csv_progress_repository import (
+    CsvProgressRepository,
+)
+from flash_card.infrastructure.persistence.csv_word_list import (
+    read_word_list,
+    write_word_list,
+)
+
+PAIR = LanguagePair("ms", "da")
+CARDS = (Card("aku", "mig"), Card("kau", "du"))
+
+
+def test_write_word_list_round_trips_through_read_word_list(tmp_path: Path) -> None:
+    path = tmp_path / "w.csv"
+    write_word_list(path, PAIR, CARDS)
+    assert read_word_list(path) == (PAIR, CARDS)
+
+
+def test_write_word_list_writes_header_and_rows_with_semicolon(
+    tmp_path: Path,
+) -> None:
+    path = tmp_path / "w.csv"
+    write_word_list(path, PAIR, CARDS)
+    raw = path.read_bytes()
+    assert raw.decode("utf-8-sig") == "ms;da\naku;mig\nkau;du\n"
+    assert b"\r" not in raw
+
+
+def test_write_word_list_keeps_non_ascii_text(tmp_path: Path) -> None:
+    path = tmp_path / "w.csv"
+    cards = (Card("chaque", "each"), Card("parlé", "speak"))
+    write_word_list(path, LanguagePair("fr", "en"), cards)
+    assert read_word_list(path)[1] == cards
+
+
+def test_write_word_list_writes_header_only_for_no_cards(tmp_path: Path) -> None:
+    path = tmp_path / "w.csv"
+    write_word_list(path, PAIR, ())
+    assert read_word_list(path) == (PAIR, ())
+
+
+def test_write_word_list_creates_parent_folder(tmp_path: Path) -> None:
+    path = tmp_path / "data" / "deep" / "w.csv"
+    write_word_list(path, PAIR, CARDS)
+    assert path.is_file()
+
+
+def test_write_word_list_replaces_file_and_leaves_no_temporary_file(
+    tmp_path: Path,
+) -> None:
+    path = tmp_path / "w.csv"
+    write_word_list(path, PAIR, CARDS)
+    write_word_list(path, PAIR, CARDS[:1])
+    assert read_word_list(path)[1] == CARDS[:1]
+    assert [item.name for item in tmp_path.iterdir()] == ["w.csv"]
+
+
+def test_write_word_list_keeps_old_file_and_no_temporary_when_write_fails(
+    tmp_path: Path,
+) -> None:
+    path = tmp_path / "w.csv"
+    write_word_list(path, PAIR, CARDS)
+    unencodable = (Card("aku", "\ud800"),)
+    with pytest.raises(UnicodeEncodeError):
+        write_word_list(path, PAIR, unencodable)
+    assert read_word_list(path)[1] == CARDS
+    assert [item.name for item in tmp_path.iterdir()] == ["w.csv"]
+
+
+def test_progress_load_returns_none_when_file_is_missing(tmp_path: Path) -> None:
+    assert CsvProgressRepository(tmp_path / "p.csv").load() is None
+
+
+def test_progress_load_returns_empty_deck_for_header_only_file(
+    tmp_path: Path,
+) -> None:
+    path = tmp_path / "p.csv"
+    path.write_text("ms;da\n", encoding="utf-8")
+    deck = CsvProgressRepository(path).load()
+    assert deck is not None
+    assert deck.is_empty
+    assert deck.language_pair == PAIR
+
+
+def test_progress_load_raises_format_error_and_keeps_malformed_file(
+    tmp_path: Path,
+) -> None:
+    path = tmp_path / "p.csv"
+    content = b"ms;da\naku;mig;extra\n"
+    path.write_bytes(content)
+    with pytest.raises(VocabularyFormatError):
+        CsvProgressRepository(path).load()
+    assert path.read_bytes() == content
+
+
+def test_progress_save_then_load_returns_same_cards(tmp_path: Path) -> None:
+    repository = CsvProgressRepository(tmp_path / "p.csv")
+    repository.save(Deck(PAIR, CARDS))
+    deck = repository.load()
+    assert deck is not None
+    assert deck.cards == CARDS
+    assert deck.language_pair == PAIR

tests/unit/test_flash_card_view_model.py

@@ -20,8 +20,22 @@ def _first(cards: Sequence[Card]) -> Card:
     return cards[0]
 
 
-def _session(code: str, *cards: Card) -> StudySession:
-    return StudySession(Deck(LanguagePair(code, "da"), cards), _first)
+class _RecordingProgress:
+    def __init__(self) -> None:
+        self.saved: list[tuple[Card, ...]] = []
+
+    def load(self) -> Deck | None:
+        return None
+
+    def save(self, deck: Deck) -> None:
+        self.saved.append(deck.cards)
+
+
+def _session(
+    code: str, *cards: Card, progress: _RecordingProgress | None = None
+) -> StudySession:
+    store = _RecordingProgress() if progress is None else progress
+    return StudySession(Deck(LanguagePair(code, "da"), cards), _first, store)
 
 
 def test_view_model_draws_first_card_on_construction() -> None:
@@ -90,3 +104,45 @@ def test_next_card_resets_side_to_front() -> None:
     assert view_model.side is Side.FRONT
     assert view_model.language_name == "Malay"
     assert view_model.text == "kau"
+
+
+def test_is_known_saves_remaining_and_shows_next_front() -> None:
+    progress = _RecordingProgress()
+    view_model = FlashCardViewModel(_session("ms", A, B, progress=progress))
+    view_model.flip_card()
+    view_model.is_known()
+    assert progress.saved == [(B,)]
+    assert view_model.side is Side.FRONT
+    assert view_model.text == "kau"
+    assert not view_model.is_finished
+
+
+def test_is_known_on_last_card_finishes() -> None:
+    progress = _RecordingProgress()
+    view_model = FlashCardViewModel(_session("ms", A, progress=progress))
+    view_model.is_known()
+    assert view_model.is_finished
+    assert view_model.text == FINISHED_MESSAGE
+    assert progress.saved == [()]
+
+
+def test_is_known_does_nothing_when_finished() -> None:
+    progress = _RecordingProgress()
+    view_model = FlashCardViewModel(_session("ms", progress=progress))
+    view_model.is_known()
+    assert view_model.is_finished
+    assert progress.saved == []
+
+
+def test_next_card_does_nothing_when_finished() -> None:
+    view_model = FlashCardViewModel(_session("ms"))
+    view_model.next_card()
+    assert view_model.is_finished
+    assert view_model.text == FINISHED_MESSAGE
+
+
+def test_next_card_never_saves() -> None:
+    progress = _RecordingProgress()
+    view_model = FlashCardViewModel(_session("ms", A, B, progress=progress))
+    view_model.next_card()
+    assert progress.saved == []