math-learing/src/main/java/com/personalproject/ui/scenes/RegistrationScene.java

package com.personalproject.ui.scenes;

import com.personalproject.controller.MathLearningController;
import com.personalproject.model.DifficultyLevel;
import com.personalproject.ui.views.MainMenuView;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.control.Alert;
import javafx.scene.control.Button;
import javafx.scene.control.ComboBox;
import javafx.scene.control.Label;
import javafx.scene.control.PasswordField;
import javafx.scene.control.ScrollPane;
import javafx.scene.control.TextField;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.VBox;
import javafx.scene.text.Font;
import javafx.scene.text.FontWeight;
import javafx.stage.Stage;

/**
 * 负责处理用户注册的场景.
 */
public class RegistrationScene extends BorderPane {

  private final Stage primaryStage;
  private final MathLearningController controller;
  private TextField usernameField;
  private TextField emailField;
  private ComboBox<DifficultyLevel> difficultyComboBox;
  private Button sendCodeButton;
  private TextField registrationCodeField;
  private Button verifyCodeButton;
  private PasswordField passwordField;
  private PasswordField confirmPasswordField;
  private Button setPasswordButton;
  private Button backButton;
  private VBox registrationForm;

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

  /**
   * 初始化界面组件.
   */
  private void initializeUi() {
    // 创建主布局
    VBox mainLayout = new VBox(15);
    mainLayout.setAlignment(Pos.TOP_CENTER);
    mainLayout.setPadding(new Insets(20));

    // 标题
    final Label titleLabel = new Label("用户注册");
    titleLabel.setFont(Font.font("System", FontWeight.BOLD, 24));

    // 注册表单
    registrationForm = new VBox(15);
    registrationForm.setAlignment(Pos.CENTER);

    // 步骤1：填写基础信息
    GridPane basicInfoForm = new GridPane();
    basicInfoForm.setHgap(10);
    basicInfoForm.setVgap(10);
    basicInfoForm.setAlignment(Pos.CENTER);

    final Label usernameLabel = new Label("用户名:");
    usernameField = new TextField();
    usernameField.setPrefWidth(200);

    final Label emailLabel = new Label("邮箱:");
    emailField = new TextField();
    emailField.setPrefWidth(200);

    final Label difficultyLabel = new Label("默认难度:");
    difficultyComboBox = new ComboBox<>();
    difficultyComboBox.getItems()
        .addAll(DifficultyLevel.PRIMARY, DifficultyLevel.MIDDLE, DifficultyLevel.HIGH);
    difficultyComboBox.setValue(DifficultyLevel.PRIMARY);
    difficultyComboBox.setPrefWidth(200);

    basicInfoForm.add(usernameLabel, 0, 0);
    basicInfoForm.add(usernameField, 1, 0);
    basicInfoForm.add(emailLabel, 0, 1);
    basicInfoForm.add(emailField, 1, 1);
    basicInfoForm.add(difficultyLabel, 0, 2);
    basicInfoForm.add(difficultyComboBox, 1, 2);

    sendCodeButton = new Button("发送注册码");
    sendCodeButton.setPrefWidth(120);

    registrationForm.getChildren().addAll(basicInfoForm, sendCodeButton);

    // 步骤2：验证码验证（初始隐藏）
    VBox verificationSection = new VBox(10);
    verificationSection.setAlignment(Pos.CENTER);
    verificationSection.setVisible(false);
    verificationSection.setManaged(false);

    final Label codeLabel = new Label("注册码:");
    registrationCodeField = new TextField();
    registrationCodeField.setPrefWidth(200);

    verifyCodeButton = new Button("验证注册码");
    verifyCodeButton.setPrefWidth(120);

    verificationSection.getChildren().addAll(codeLabel, registrationCodeField, verifyCodeButton);
    registrationForm.getChildren().add(verificationSection);

    // 步骤3：设置密码（初始隐藏）
    VBox passwordSection = new VBox(10);
    passwordSection.setAlignment(Pos.CENTER);
    passwordSection.setVisible(false);
    passwordSection.setManaged(false);

    final Label passwordLabel = new Label("设置密码 (6-10位，包含大小写字母和数字):");
    passwordField = new PasswordField();
    passwordField.setPrefWidth(200);

    final Label confirmPasswordLabel = new Label("确认密码:");
    confirmPasswordField = new PasswordField();
    confirmPasswordField.setPrefWidth(200);

    setPasswordButton = new Button("设置密码");
    setPasswordButton.setPrefWidth(120);

    passwordSection.getChildren().addAll(passwordLabel, passwordField, confirmPasswordLabel,
        confirmPasswordField, setPasswordButton);
    registrationForm.getChildren().add(passwordSection);

    // 返回按钮
    backButton = new Button("返回");
    backButton.setPrefWidth(100);

    // 将组件添加到主布局
    mainLayout.getChildren().addAll(titleLabel, registrationForm, backButton);

    // 使用可滚动容器保证内容在小窗口中完整显示
    ScrollPane scrollPane = new ScrollPane(mainLayout);
    scrollPane.setFitToWidth(true);
    scrollPane.setHbarPolicy(ScrollPane.ScrollBarPolicy.NEVER);
    setCenter(scrollPane);

    // 添加事件处理器
    addEventHandlers(sendCodeButton, verificationSection, verifyCodeButton, passwordSection);
  }

  /**
   * 为界面组件添加事件处理器.
   */
  private void addEventHandlers(Button sendCodeButton, VBox verificationSection,
      Button verifyCodeButton, VBox passwordSection) {
    sendCodeButton.setOnAction(e -> handleSendCode(verificationSection));
    verifyCodeButton.setOnAction(e -> handleVerifyCode(passwordSection));
    setPasswordButton.setOnAction(e -> handleSetPassword());
    backButton.setOnAction(e -> handleBack());
  }

  /**
   * 处理发送注册码的逻辑.
   */
  private void handleSendCode(VBox verificationSection) {
    final String username = usernameField.getText().trim();
    final String email = emailField.getText().trim();
    final DifficultyLevel difficultyLevel = difficultyComboBox.getValue();

    if (username.isEmpty() || email.isEmpty()) {
      showAlert(Alert.AlertType.WARNING, "警告", "请输入用户名和邮箱");
      return;
    }

    if (!controller.isValidEmail(email)) {
      showAlert(Alert.AlertType.ERROR, "邮箱格式错误", "请输入有效的邮箱地址");
      return;
    }

    // 发起注册
    boolean success = controller.initiateRegistration(username, email, difficultyLevel);

    if (success) {
      showAlert(Alert.AlertType.INFORMATION, "注册码已发送", "注册码已发送至您的邮箱，请查收。");
      verificationSection.setVisible(true);
      verificationSection.setManaged(true);
    } else {
      showAlert(Alert.AlertType.ERROR, "注册失败", "用户名或邮箱可能已存在，请重试。");
    }
  }

  /**
   * 处理注册码验证.
   */
  private void handleVerifyCode(VBox passwordSection) {
    final String username = usernameField.getText().trim();
    final String registrationCode = registrationCodeField.getText().trim();

    if (registrationCode.isEmpty()) {
      showAlert(Alert.AlertType.WARNING, "警告", "请输入注册码");
      return;
    }

    boolean verified = controller.verifyRegistrationCode(username, registrationCode);

    if (verified) {
      showAlert(Alert.AlertType.INFORMATION, "验证成功", "注册码验证成功！");
      passwordSection.setVisible(true);
      passwordSection.setManaged(true);
    } else {
      showAlert(Alert.AlertType.ERROR, "验证失败", "注册码验证失败，请检查后重试。");
    }
  }

  /**
   * 处理设置用户密码的逻辑.
   */
  private void handleSetPassword() {
    final String username = usernameField.getText().trim();
    final String password = passwordField.getText();
    final String confirmPassword = confirmPasswordField.getText();

    if (password.isEmpty() || confirmPassword.isEmpty()) {
      showAlert(Alert.AlertType.WARNING, "警告", "请输入并确认密码");
      return;
    }

    if (!password.equals(confirmPassword)) {
      showAlert(Alert.AlertType.ERROR, "密码不匹配", "两次输入的密码不一致");
      return;
    }

    if (!controller.isValidPassword(password)) {
      showAlert(Alert.AlertType.ERROR, "密码不符合要求",
          "密码长度必须为6-10位，且包含大小写字母和数字");
      return;
    }

    boolean success = controller.setPassword(username, password);

    if (success) {
      var userAccountOptional = controller.getUserAccount(username);
      if (userAccountOptional.isPresent()) {
        showAlert(Alert.AlertType.INFORMATION, "注册成功", "注册成功！正在进入难度选择界面。");
        MainMenuView mainMenuView = new MainMenuView(primaryStage, controller,
            userAccountOptional.get());
        if (primaryStage.getScene() != null) {
          primaryStage.getScene().setRoot(mainMenuView);
        }
      } else {
        showAlert(Alert.AlertType.WARNING, "注册提示",
            "注册成功，但未能加载用户信息，请使用新密码登录。");
        handleBack();
      }
    } else {
      showAlert(Alert.AlertType.ERROR, "设置密码失败", "设置密码失败，请重试。");
    }
  }

  /**
   * 处理返回按钮的操作.
   */
  private void handleBack() {
    LoginScene loginScene = new LoginScene(primaryStage, controller);
    primaryStage.getScene().setRoot(loginScene);
  }

  /**
   * 显示提示对话框.
   *
   * @param alertType 提示类型
   * @param title     对话框标题
   * @param message   显示的消息
   */
  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();
  }
}