Add system user and log attribution

feat: log poll and lottery results

backend/src/main/java/com/openisle/config/SystemUserInitializer.java

@@ -0,0 +1,34 @@
+package com.openisle.config;
+
+import com.openisle.model.Role;
+import com.openisle.model.User;
+import com.openisle.repository.UserRepository;
+import lombok.RequiredArgsConstructor;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.stereotype.Component;
+
+/**
+ * Ensure a dedicated "system" user exists for internal operations.
+ */
+@Component
+@RequiredArgsConstructor
+public class SystemUserInitializer implements CommandLineRunner {
+    private final UserRepository userRepository;
+    private final PasswordEncoder passwordEncoder;
+
+    @Override
+    public void run(String... args) {
+        userRepository.findByUsername("system").orElseGet(() -> {
+            User system = new User();
+            system.setUsername("system");
+            system.setEmail("system@openisle.local");
+            system.setPassword(passwordEncoder.encode("system"));
+            system.setRole(Role.ADMIN);
+            system.setVerified(true);
+            system.setApproved(true);
+            return userRepository.save(system);
+        });
+    }
+}
+

backend/src/main/java/com/openisle/dto/PostChangeLogDto.java

@@ -5,6 +5,7 @@ import lombok.Getter;
 import lombok.Setter;
 
 import java.time.LocalDateTime;
+import java.util.List;
 
 @Getter
 @Setter
@@ -18,10 +19,10 @@ public class PostChangeLogDto {
     private String newTitle;
     private String oldContent;
     private String newContent;
-    private String oldCategory;
-    private String newCategory;
-    private String oldTags;
-    private String newTags;
+    private CategoryDto oldCategory;
+    private CategoryDto newCategory;
+    private List<TagDto> oldTags;
+    private List<TagDto> newTags;
     private Boolean oldClosed;
     private Boolean newClosed;
     private LocalDateTime oldPinnedAt;

backend/src/main/java/com/openisle/mapper/PostChangeLogMapper.java

@@ -1,11 +1,28 @@
 package com.openisle.mapper;
 
+import com.openisle.dto.CategoryDto;
 import com.openisle.dto.PostChangeLogDto;
+import com.openisle.dto.TagDto;
 import com.openisle.model.*;
+import com.openisle.repository.CategoryRepository;
+import com.openisle.repository.TagRepository;
+import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Component;
 
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.stream.Collectors;
+
 @Component
+@RequiredArgsConstructor
 public class PostChangeLogMapper {
+
+    private final CategoryRepository categoryRepository;
+    private final TagRepository tagRepository;
+    private final CategoryMapper categoryMapper;
+    private final TagMapper tagMapper;
+
     public PostChangeLogDto toDto(PostChangeLog log) {
         PostChangeLogDto dto = new PostChangeLogDto();
         dto.setId(log.getId());
@@ -22,11 +39,11 @@ public class PostChangeLogMapper {
             dto.setOldContent(c.getOldContent());
             dto.setNewContent(c.getNewContent());
         } else if (log instanceof PostCategoryChangeLog cat) {
-            dto.setOldCategory(cat.getOldCategory());
-            dto.setNewCategory(cat.getNewCategory());
+            dto.setOldCategory(mapCategory(cat.getOldCategory()));
+            dto.setNewCategory(mapCategory(cat.getNewCategory()));
         } else if (log instanceof PostTagChangeLog tag) {
-            dto.setOldTags(tag.getOldTags());
-            dto.setNewTags(tag.getNewTags());
+            dto.setOldTags(mapTags(tag.getOldTags()));
+            dto.setNewTags(mapTags(tag.getNewTags()));
         } else if (log instanceof PostClosedChangeLog cl) {
             dto.setOldClosed(cl.isOldClosed());
             dto.setNewClosed(cl.isNewClosed());
@@ -39,4 +56,37 @@ public class PostChangeLogMapper {
         }
         return dto;
     }
+
+    private CategoryDto mapCategory(String name) {
+        if (name == null) {
+            return null;
+        }
+        return categoryRepository.findByName(name)
+                .map(categoryMapper::toDto)
+                .orElseGet(() -> {
+                    CategoryDto dto = new CategoryDto();
+                    dto.setName(name);
+                    return dto;
+                });
+    }
+
+    private List<TagDto> mapTags(String tags) {
+        if (tags == null || tags.isBlank()) {
+            return Collections.emptyList();
+        }
+        return Arrays.stream(tags.split(","))
+                .map(String::trim)
+                .map(this::mapTag)
+                .collect(Collectors.toList());
+    }
+
+    private TagDto mapTag(String name) {
+        return tagRepository.findByName(name)
+                .map(tagMapper::toDto)
+                .orElseGet(() -> {
+                    TagDto dto = new TagDto();
+                    dto.setName(name);
+                    return dto;
+                });
+    }
 }

backend/src/main/java/com/openisle/repository/CategoryRepository.java

@@ -4,7 +4,10 @@ import com.openisle.model.Category;
 import org.springframework.data.jpa.repository.JpaRepository;
 
 import java.util.List;
+import java.util.Optional;
 
 public interface CategoryRepository extends JpaRepository<Category, Long> {
     List<Category> findByNameContainingIgnoreCase(String keyword);
+
+    Optional<Category> findByName(String name);
 }

backend/src/main/java/com/openisle/repository/TagRepository.java

@@ -6,6 +6,7 @@ import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.data.domain.Pageable;
 
 import java.util.List;
+import java.util.Optional;
 
 public interface TagRepository extends JpaRepository<Tag, Long> {
     List<Tag> findByNameContainingIgnoreCase(String keyword);
@@ -15,4 +16,6 @@ public interface TagRepository extends JpaRepository<Tag, Long> {
 
     List<Tag> findByCreatorOrderByCreatedAtDesc(User creator, Pageable pageable);
     List<Tag> findByCreator(User creator);
+
+    Optional<Tag> findByName(String name);
 }

backend/src/main/java/com/openisle/service/PostChangeLogService.java

@@ -3,6 +3,7 @@ package com.openisle.service;
 import com.openisle.model.*;
 import com.openisle.repository.PostChangeLogRepository;
 import com.openisle.repository.PostRepository;
+import com.openisle.repository.UserRepository;
 import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Service;
 
@@ -15,6 +16,12 @@ import java.util.stream.Collectors;
 public class PostChangeLogService {
     private final PostChangeLogRepository logRepository;
     private final PostRepository  postRepository;
+    private final UserRepository userRepository;
+
+    private User getSystemUser() {
+        return userRepository.findByUsername("system")
+                .orElseThrow(() -> new IllegalStateException("System user not found"));
+    }
 
     public void recordContentChange(Post post, User user, String oldContent, String newContent) {
         PostContentChangeLog log = new PostContentChangeLog();
@@ -89,6 +96,7 @@ public class PostChangeLogService {
     public void recordVoteResult(Post post) {
         PostVoteResultChangeLog log = new PostVoteResultChangeLog();
         log.setPost(post);
+        log.setUser(getSystemUser());
         log.setType(PostChangeType.VOTE_RESULT);
         logRepository.save(log);
     }
@@ -96,6 +104,7 @@ public class PostChangeLogService {
     public void recordLotteryResult(Post post) {
         PostLotteryResultChangeLog log = new PostLotteryResultChangeLog();
         log.setPost(post);
+        log.setUser(getSystemUser());
         log.setType(PostChangeType.LOTTERY_RESULT);
         logRepository.save(log);
     }

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

@@ -368,6 +368,7 @@ public class PostService {
             for (User participant : pp.getParticipants()) {
                 notificationService.createNotification(participant, NotificationType.POLL_RESULT_PARTICIPANT, pp, null, null, null, null, null);
             }
+            postChangeLogService.recordVoteResult(pp);
         });
     }
 
@@ -402,6 +403,7 @@ public class PostService {
                 notificationService.createNotification(lp.getAuthor(), NotificationType.LOTTERY_DRAW, lp, null, null, null, null, null);
                 notificationService.sendCustomPush(lp.getAuthor(), "抽奖已开奖", String.format("%s/posts/%d", websiteUrl, lp.getId()));
             }
+            postChangeLogService.recordLotteryResult(lp);
         });
     }
 

frontend_nuxt/components/PostChangeLogItem.vue

@@ -11,8 +11,18 @@
       <span v-if="log.username" class="change-log-user">{{ log.username }}</span>
       <span v-if="log.type === 'CONTENT'" class="change-log-content">变更了文章内容</span>
       <span v-else-if="log.type === 'TITLE'" class="change-log-content">变更了文章标题</span>
-      <span v-else-if="log.type === 'CATEGORY'" class="change-log-content">变更了文章分类</span>
-      <span v-else-if="log.type === 'TAG'" class="change-log-content">变更了文章标签</span>
+      <span v-else-if="log.type === 'CATEGORY'" class="change-log-content change-log-category">
+        <div class="change-log-category-text">变更了文章分类, 从</div>
+        <ArticleCategory :category="log.oldCategory" />
+        <div class="change-log-category-text">修改为</div>
+        <ArticleCategory :category="log.newCategory" />
+      </span>
+      <span v-else-if="log.type === 'TAG'" class="change-log-content change-log-category">
+        <div class="change-log-category-text">变更了文章标签, 从</div>
+        <ArticleTags :tags="log.oldTags" />
+        <div class="change-log-category-text">修改为</div>
+        <ArticleTags :tags="log.newTags" />
+      </span>
       <span v-else-if="log.type === 'CLOSED'" class="change-log-content">
         <template v-if="log.newClosed">关闭了文章</template>
         <template v-else>重新打开了文章</template>
@@ -46,6 +56,8 @@ import 'diff2html/bundles/css/diff2html.min.css'
 import BaseImage from '~/components/BaseImage.vue'
 import { navigateTo } from 'nuxt/app'
 import { themeState } from '~/utils/theme'
+import ArticleCategory from '~/components/ArticleCategory.vue'
+import ArticleTags from '~/components/ArticleTags.vue'
 const props = defineProps({
   log: Object,
   title: String,
@@ -124,4 +136,11 @@ const diffHtml = computed(() => {
 .content-diff {
   margin-top: 8px;
 }
+
+.change-log-category {
+  display: flex;
+  flex-direction: row;
+  gap: 4px;
+  align-items: center;
+}
 </style>