MIL-008: Choose level

Review record RC-041 (Go, autonomous mode, not independent).

Task: MIL-008#1
Task: MIL-008#2
Task: MIL-008#3
Task: MIL-008#4
Task: MIL-008#5
Task: MIL-008#6
Task: MIL-008#7
Task: MIL-008#8

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

@@ -20,8 +20,6 @@ from flash_card.constants import (
     LANGUAGE_FONT,
     LANGUAGE_TEXT_Y,
     RIGHT_IMAGE_NAME,
-    WINDOW_PADDING,
-    WINDOW_TITLE,
     WORD_FONT,
     WORD_TEXT_Y,
     WRONG_IMAGE_NAME,
@@ -30,6 +28,7 @@ from flash_card.presentation.features.flash_card.flash_card_view_model import (
     FlashCardViewModel,
     Side,
 )
+from flash_card.presentation.shared.window import configure_window
 
 
 def _load_image(root: tk.Tk, name: str) -> tk.PhotoImage:
@@ -60,8 +59,7 @@ class FlashCardView:
         self._root = root
         ## @brief The data source of the texts.
         self._view_model = view_model
-        root.title(WINDOW_TITLE)
-        root.config(padx=WINDOW_PADDING, pady=WINDOW_PADDING, bg=BACKGROUND_COLOR)
+        configure_window(root)
 
         # Kept as attributes: Tkinter drops an image nothing refers to.
         ## @brief Card front image, kept so Tk does not drop it.

src/flash_card/presentation/features/level/__init__.py

@@ -0,0 +1 @@
+"""The level feature: its view and view model."""

src/flash_card/presentation/features/level/level_view.py

@@ -0,0 +1,97 @@
+"""View of the level screen.
+
+@file level_view.py
+@brief Builds the level screen of the wireframe: a title and one button per level.
+"""
+
+import tkinter as tk
+from collections.abc import Callable
+
+from flash_card.constants import (
+    BACKGROUND_COLOR,
+    CARD_WIDTH,
+    LEVEL_BUTTON_COLOR,
+    LEVEL_BUTTON_FONT,
+    LEVEL_BUTTON_WIDTH,
+    LEVEL_SCREEN_HEIGHT,
+    LEVEL_TITLE_FONT,
+)
+from flash_card.domain.value_objects.level import Level
+from flash_card.presentation.features.level.level_view_model import (
+    LevelChoice,
+    LevelViewModel,
+)
+
+
+class LevelView:
+    """The level screen: a title and a button for each level."""
+
+    def __init__(
+        self,
+        root: tk.Tk,
+        view_model: LevelViewModel,
+        on_choose: Callable[[Level], None],
+    ) -> None:
+        """Build the screen on a root.
+
+        @param root The Tk root window.
+        @param view_model The data to show.
+        @param on_choose Called with the level the user picked.
+        """
+        ## @brief Called with the level the user picked.
+        self._on_choose = on_choose
+        ## @brief Frame that holds the whole screen.
+        self.frame = tk.Frame(
+            root, bg=BACKGROUND_COLOR, width=CARD_WIDTH, height=LEVEL_SCREEN_HEIGHT
+        )
+        self.frame.grid(row=0, column=0)
+        self.frame.grid_propagate(False)
+        self.frame.grid_columnconfigure(0, weight=1)
+        for row in range(len(view_model.choices) + 1):
+            self.frame.grid_rowconfigure(row, weight=1)
+        ## @brief The title text.
+        self.title_label = tk.Label(
+            self.frame,
+            text=view_model.title,
+            font=LEVEL_TITLE_FONT,
+            bg=BACKGROUND_COLOR,
+        )
+        self.title_label.grid(row=0, column=0)
+        ## @brief One button per choice, in display order.
+        self.buttons = tuple(
+            self._build_button(row, choice)
+            for row, choice in enumerate(view_model.choices, start=1)
+        )
+
+    def choose(self, level: Level) -> None:
+        """Forward the chosen level.
+
+        @param level The level the user picked.
+        @return Nothing.
+        """
+        self._on_choose(level)
+
+    def destroy(self) -> None:
+        """Remove the screen from the window.
+
+        @return Nothing.
+        """
+        self.frame.destroy()
+
+    def _build_button(self, row: int, choice: LevelChoice) -> tk.Button:
+        """Create the button of one choice.
+
+        @param row Grid row of the button.
+        @param choice The choice the button stands for.
+        @return The button, placed in the frame.
+        """
+        button = tk.Button(
+            self.frame,
+            text=choice.label,
+            font=LEVEL_BUTTON_FONT,
+            width=LEVEL_BUTTON_WIDTH,
+            bg=LEVEL_BUTTON_COLOR,
+            command=lambda: self.choose(choice.level),
+        )
+        button.grid(row=row, column=0)
+        return button

src/flash_card/presentation/features/level/level_view_model.py

@@ -0,0 +1,53 @@
+"""View model of the level screen.
+
+@file level_view_model.py
+@brief Exposes the title and the level choices; free of any Tkinter import.
+"""
+
+from collections.abc import Sequence
+from dataclasses import dataclass
+
+from flash_card.constants import LEVEL_CHOICES, LEVEL_TITLE
+from flash_card.domain.value_objects.level import Level
+
+
+@dataclass(frozen=True, slots=True)
+class LevelChoice:
+    """One choice on the level screen."""
+
+    ## @brief Text of the choice.
+    label: str
+    ## @brief The level the choice stands for.
+    level: Level
+
+
+class LevelViewModel:
+    """Data the level view shows."""
+
+    def __init__(self, choices: Sequence[tuple[str, int | None]] | None = None) -> None:
+        """Create the view model.
+
+        @param choices Label and word limit of each choice, or None for the
+            choices of the program.
+        """
+        source = LEVEL_CHOICES if choices is None else choices
+        ## @brief The choices in display order.
+        self._choices = tuple(
+            LevelChoice(label, Level(limit)) for label, limit in source
+        )
+
+    @property
+    def title(self) -> str:
+        """Return the title of the screen.
+
+        @return The title text.
+        """
+        return LEVEL_TITLE
+
+    @property
+    def choices(self) -> tuple[LevelChoice, ...]:
+        """Return the choices.
+
+        @return The choices in display order.
+        """
+        return self._choices