math-learing/src/main/java/com/personalproject/ui/views/MainMenuView.java

package com.personalproject.ui.views;

import com.personalproject.auth.UserAccount;
import com.personalproject.controller.MathLearningController;
import com.personalproject.model.DifficultyLevel;
import com.personalproject.ui.scenes.LoginScene;
import java.util.Optional;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.control.Alert;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.TextInputDialog;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.VBox;
import javafx.scene.text.Font;
import javafx.scene.text.FontWeight;
import javafx.stage.Stage;

/**
 * 用户可以开始考试或更改设置的主菜单界面.
 */
public class MainMenuView extends BorderPane {

  private final Stage primaryStage;
  private final MathLearningController controller;
  private final UserAccount userAccount;
  private Button changePasswordButton;
  private Button logoutButton;

  /**
   * MainMenuView 的构造函数.
   *
   * @param primaryStage 应用程序的主舞台
   * @param controller   数学学习控制器
   * @param userAccount  当前用户账户
   */
  public MainMenuView(Stage primaryStage, MathLearningController controller,
      UserAccount userAccount) {
    this.primaryStage = primaryStage;
    this.controller = controller;
    this.userAccount = userAccount;
    initializeUi();
  }

  /**
   * 初始化界面组件.
   */
  private void initializeUi() {
    // 创建主布局
    VBox mainLayout = new VBox(20);
    mainLayout.setAlignment(Pos.CENTER);
    mainLayout.setPadding(new Insets(20));

    // 欢迎信息
    Label welcomeLabel = new Label("欢迎, " + userAccount.username());
    welcomeLabel.setFont(Font.font("System", FontWeight.BOLD, 18));

    // 难度信息
    Label difficultyLabel = new Label(
        "当前难度: " + userAccount.difficultyLevel().getDisplayName());
    difficultyLabel.setFont(Font.font("System", FontWeight.NORMAL, 14));

    Label promptLabel = new Label("请选择考试难度开始答题");
    promptLabel.setFont(Font.font("System", FontWeight.NORMAL, 14));

    VBox difficultyBox = new VBox(10);
    difficultyBox.setAlignment(Pos.CENTER);
    difficultyBox.getChildren().addAll(
        createDifficultyButton(DifficultyLevel.PRIMARY),
        createDifficultyButton(DifficultyLevel.MIDDLE),
        createDifficultyButton(DifficultyLevel.HIGH));

    // 按钮区域
    VBox buttonBox = new VBox(15);
    buttonBox.setAlignment(Pos.CENTER);

    changePasswordButton = new Button("修改密码");
    logoutButton = new Button("退出登录");

    // 设置按钮尺寸
    changePasswordButton.setPrefSize(150, 40);
    logoutButton.setPrefSize(150, 40);

    buttonBox.getChildren().addAll(changePasswordButton, logoutButton);

    // 将组件添加到主布局
    mainLayout.getChildren().addAll(welcomeLabel, difficultyLabel, promptLabel, difficultyBox,
        buttonBox);

    // 将主布局置于边界面板中央
    setCenter(mainLayout);

    // 添加事件处理器
    addEventHandlers();
  }

  /**
   * 为界面组件添加事件处理器.
   */
  private void addEventHandlers() {
    changePasswordButton.setOnAction(e -> handleChangePassword());
    logoutButton.setOnAction(e -> handleLogout());
  }

  private Button createDifficultyButton(DifficultyLevel level) {
    Button button = new Button(level.getDisplayName());
    button.setPrefSize(150, 40);
    button.setOnAction(e -> handleDifficultySelection(level));
    return button;
  }

  private void handleDifficultySelection(DifficultyLevel level) {
    TextInputDialog dialog = new TextInputDialog("10");
    dialog.setTitle("题目数量");
    dialog.setHeaderText("请选择题目数量");
    dialog.setContentText("请输入题目数量 (10-30):");

    Optional<String> result = dialog.showAndWait();
    if (result.isEmpty()) {
      return;
    }

    int questionCount;
    try {
      questionCount = Integer.parseInt(result.get().trim());
    } catch (NumberFormatException ex) {
      showAlert(Alert.AlertType.ERROR, "无效输入", "请输入有效的数字。");
      return;
    }

    if (questionCount < 10 || questionCount > 30) {
      showAlert(Alert.AlertType.WARNING, "题目数量范围错误", "题目数量必须在10到30之间。");
      return;
    }

    com.personalproject.model.ExamSession examSession = controller.createExamSession(
        userAccount.username(), level, questionCount);

    ExamView examView = new ExamView(primaryStage, controller, examSession);
    primaryStage.getScene().setRoot(examView);
  }

  /**
   * 处理修改密码按钮的操作.
   */
  private void handleChangePassword() {
    PasswordChangeView passwordChangeView = new PasswordChangeView(primaryStage, controller,
        userAccount);
    primaryStage.getScene().setRoot(passwordChangeView);
  }

  private void showAlert(Alert.AlertType alertType, String title, String message) {
    Alert alert = new Alert(alertType);
    alert.setTitle(title);
    alert.setHeaderText(null);
    alert.setContentText(message);
    alert.showAndWait();
  }

  /**
   * 处理退出登录按钮的操作.
   */
  private void handleLogout() {
    // 返回登录界面
    LoginScene loginScene = new LoginScene(primaryStage, controller);
    primaryStage.getScene().setRoot(loginScene);
  }
}