feat: 完善登录后题目处理逻辑

src/Main.java

@@ -5,6 +5,7 @@ import model.User;
 import java.util.Scanner;
 
 public class Main {
+    private static final AuthService authService = new AuthService();
     private static final AuthService.TestPaperService testPaperService = new AuthService.TestPaperService();
     private static User currentUser = null;
     private static Level currentLevel = null;
@@ -37,4 +38,29 @@ public class Main {
             System.out.println("输入格式不正确，请重新输入。");
         }
     }
+
+    private static void handleQuestionGeneration(Scanner scanner) {
+        System.out.printf("准备生成%s数学题目, 请输入生成题目数量(输入-1将退出当前用户, 重新登录):%n", currentLevel.getName()); // 生成提示
+        String input = scanner.nextLine();
+
+//        if (input.startsWith("切换为")) { // 切换类型功能
+//            handleLevelSwitch(input);
+//            return;
+//        }
+
+        try {
+            int count = Integer.parseInt(input);
+            if (count == -1) {
+                currentUser = null;
+                currentLevel = null;
+                System.out.println("已退出，请重新登录。");
+            } else if (count >= 10 && count <= 30) { // 题目数量的有效输入范围是“10-30”
+//                testPaperService.generateAndSave(currentUser, currentLevel, count);
+            } else {
+                System.out.println("输入无效，请输入10-30之间的数字或-1。");
+            }
+        } catch (NumberFormatException e) {
+            System.out.println("输入无效，请输入一个数字。");
+        }
+    }
 }

src/auth/AuthService.java

@@ -3,8 +3,13 @@ package auth;
 import model.Level;
 import model.User;
 
-import java.util.ArrayList;
-import java.util.List;
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.*;
+import java.util.stream.Stream;
 
 public class AuthService {
     private final List<User> users;
@@ -22,4 +27,41 @@ public class AuthService {
         users.add(new User("王五2", "123", Level.SENIOR_HIGH));
         users.add(new User("王五3", "123", Level.SENIOR_HIGH));
     }
+
+    public Optional<User> login(String username, String password) {
+        return users.stream()
+                .filter(user -> user.getUsername().equals(username) && user.getPassword().equals(password))
+                .findFirst();
+    }
+
+    public static class TestPaperService {
+
+        public Set<String> loadExistingQuestions(String username) {
+            Set<String> questions = new HashSet<>();
+            File userDir = new File(username);
+            if (!userDir.exists() || !userDir.isDirectory()) {
+                return questions;
+            }
+
+            try (Stream<Path> paths = Files.walk(Paths.get(username))) {
+                paths.filter(Files::isRegularFile)
+                        .filter(path -> path.toString().endsWith(".txt"))
+                        .forEach(path -> {
+                            try {
+                                Files.lines(path).forEach(line -> {
+                                    // 简单的题目提取逻辑，假设每行都是一个题目
+                                    if (line.matches("^\\d+\\.\\s.*")) {
+                                        questions.add(line.substring(line.indexOf(' ') + 1).trim());
+                                    }
+                                });
+                            } catch (IOException e) {
+                                System.err.println("读取历史文件失败: " + path);
+                            }
+                        });
+            } catch (IOException e) {
+                System.err.println("加载历史题目时出错: " + e.getMessage());
+            }
+            return questions;
+        }
+    }
 }