feat: implement settings page and config management

src/main/java/com/openisle/service/PasswordValidator.java

@@ -7,12 +7,20 @@ import org.springframework.stereotype.Service;
 
 @Service
 public class PasswordValidator {
-    private final PasswordStrength strength;
+    private PasswordStrength strength;
 
     public PasswordValidator(@Value("${app.password.strength:LOW}") PasswordStrength strength) {
         this.strength = strength;
     }
 
+    public PasswordStrength getStrength() {
+        return strength;
+    }
+
+    public void setStrength(PasswordStrength strength) {
+        this.strength = strength;
+    }
+
     public void validate(String password) {
         if (password == null || password.isEmpty()) {
             throw new FieldException("password", "Password cannot be empty");

src/main/java/com/openisle/service/PostService.java

@@ -24,7 +24,7 @@ public class PostService {
     private final UserRepository userRepository;
     private final CategoryRepository categoryRepository;
     private final TagRepository tagRepository;
-    private final PublishMode publishMode;
+    private PublishMode publishMode;
     private final NotificationService notificationService;
     private final SubscriptionService subscriptionService;
 
@@ -45,6 +45,14 @@ public class PostService {
         this.publishMode = publishMode;
     }
 
+    public PublishMode getPublishMode() {
+        return publishMode;
+    }
+
+    public void setPublishMode(PublishMode publishMode) {
+        this.publishMode = publishMode;
+    }
+
     public Post createPost(String username,
                            Long categoryId,
                            String title,

src/main/java/com/openisle/service/UserService.java

@@ -94,4 +94,19 @@ public class UserService {
         user.setAvatar(avatarUrl);
         return userRepository.save(user);
     }
+
+    public User updateProfile(String currentUsername, String newUsername, String introduction) {
+        User user = userRepository.findByUsername(currentUsername)
+                .orElseThrow(() -> new IllegalArgumentException("User not found"));
+        if (newUsername != null && !newUsername.equals(currentUsername)) {
+            userRepository.findByUsername(newUsername).ifPresent(u -> {
+                throw new FieldException("username", "User name already exists");
+            });
+            user.setUsername(newUsername);
+        }
+        if (introduction != null) {
+            user.setIntroduction(introduction);
+        }
+        return userRepository.save(user);
+    }
 }