MIL-003: Step 2 - New flash cards

Review record RC-025 (Go, autonomous mode, not independent).

Task: MIL-003#1
Task: MIL-003#2
Task: MIL-003#3
Task: MIL-003#4
Task: MIL-003#5

src/flash_card/presentation/features/flash_card/flash_card_view.py

@@ -84,11 +84,30 @@ class FlashCardView:
 
         ## @brief Button for a word the user does not know.
         self.wrong_button = tk.Button(
-            root, image=self._wrong_image, highlightthickness=0, bd=0
+            root,
+            image=self._wrong_image,
+            highlightthickness=0,
+            bd=0,
+            command=self.next_card,
         )
         self.wrong_button.grid(row=1, column=0)
         ## @brief Button for a word the user knows.
         self.right_button = tk.Button(
-            root, image=self._right_image, highlightthickness=0, bd=0
+            root,
+            image=self._right_image,
+            highlightthickness=0,
+            bd=0,
+            command=self.next_card,
         )
         self.right_button.grid(row=1, column=1)
+
+    def next_card(self) -> None:
+        """Show the next card.
+
+        @return Nothing.
+        """
+        self._view_model.next_card()
+        self.canvas.itemconfig(
+            self.language_text_id, text=self._view_model.language_name
+        )
+        self.canvas.itemconfig(self.word_text_id, text=self._view_model.text)

src/flash_card/presentation/features/flash_card/flash_card_view_model.py

@@ -1,27 +1,69 @@
-"""View model of the flash card screen.
-
-@file flash_card_view_model.py
-@brief Exposes the texts shown on the card; free of any Tkinter import.
-"""
-
-from flash_card.constants import PLACEHOLDER_LANGUAGE_NAME, PLACEHOLDER_WORD
-
-
-class FlashCardViewModel:
-    """Data the flash card view shows."""
-
-    @property
-    def language_name(self) -> str:
-        """Return the language name shown on the card.
-
-        @return The display name of the language.
-        """
-        return PLACEHOLDER_LANGUAGE_NAME
-
-    @property
-    def text(self) -> str:
-        """Return the word shown on the card.
-
-        @return The word text.
-        """
-        return PLACEHOLDER_WORD
+"""View model of the flash card screen.
+
+@file flash_card_view_model.py
+@brief Exposes the texts shown on the card; free of any Tkinter import.
+"""
+
+from collections.abc import Mapping
+
+from flash_card.application.dto.card_dto import CardDto
+from flash_card.application.use_cases.study_session import StudySession
+from flash_card.constants import FINISHED_MESSAGE, LANGUAGE_NAMES
+
+
+class FlashCardViewModel:
+    """Data the flash card view shows."""
+
+    def __init__(
+        self,
+        session: StudySession,
+        language_names: Mapping[str, str] = LANGUAGE_NAMES,
+    ) -> None:
+        """Create the view model and draw the first card.
+
+        @param session The study session that supplies the cards.
+        @param language_names Display names by language code.
+        """
+        ## @brief The study session that supplies the cards.
+        self._session = session
+        ## @brief Display names by language code.
+        self._language_names = language_names
+        ## @brief The card shown now, or None when none is left.
+        self._card: CardDto | None = session.next_card()
+
+    @property
+    def is_finished(self) -> bool:
+        """Tell whether no card is left to show.
+
+        @return True when there is no card.
+        """
+        return self._card is None
+
+    @property
+    def language_name(self) -> str:
+        """Return the language name shown on the card.
+
+        @return The display name of the front language, upper case code when
+            unknown, or an empty string when no card is left.
+        """
+        if self._card is None:
+            return ""
+        code = self._card.front_language
+        return self._language_names.get(code, code.upper())
+
+    @property
+    def text(self) -> str:
+        """Return the word shown on the card.
+
+        @return The front text, or the finished message when no card is left.
+        """
+        if self._card is None:
+            return FINISHED_MESSAGE
+        return self._card.front_text
+
+    def next_card(self) -> None:
+        """Draw the next card.
+
+        @return Nothing.
+        """
+        self._card = self._session.next_card()