diff --git a/docs/dev-logs/2026-03-19.md b/docs/dev-logs/2026-03-19.md
new file mode 100644
index 0000000..70df82e
--- /dev/null
+++ b/docs/dev-logs/2026-03-19.md
@@ -0,0 +1,65 @@
+# 开发日志 - 2026-03-19
+
+## Service 层重构
+
+### 背景
+
+根据项目统一开发规范要求，Service 层应采用 **接口 + 实现类** 的结构：
+
+```
+service/
+├── XxxService.java          ← 接口，继承 IService<Entity>
+└── impl/
+    └── XxxServiceImpl.java  ← 实现类，继承 ServiceImpl 并实现接口
+```
+
+### 重构内容
+
+将以下 5 个服务类从实现类拆分为接口 + 实现类结构：
+
+| 服务类 | 接口文件 | 实现类文件 | 状态 |
+|--------|---------|-----------|------|
+| `ThemeService` | `service/ThemeService.java` | `service/impl/ThemeServiceImpl.java` | ✅ |
+| `ResourceLibraryService` | `service/ResourceLibraryService.java` | `service/impl/ResourceLibraryServiceImpl.java` | ✅ |
+| `CourseLessonService` | `service/CourseLessonService.java` | `service/impl/CourseLessonServiceImpl.java` | ✅ |
+| `CourseCollectionService` | `service/CourseCollectionService.java` | `service/impl/CourseCollectionServiceImpl.java` | ✅ |
+| `FileStorageService` | 无需拆分（纯工具类） | 保持原结构 | ✅ |
+
+### 重构详情
+
+#### 1. ThemeService
+- **接口方法**：`findAll()`, `findById()`, `create()`, `update()`, `delete()`, `reorder()`
+- **实现类**：`ThemeServiceImpl` 继承 `ServiceImpl<ThemeMapper, Theme>` 并实现 `ThemeService` 接口
+
+#### 2. ResourceLibraryService
+- **接口方法**：`findAllLibraries()`, `findLibraryById()`, `createLibrary()`, `updateLibrary()`, `deleteLibrary()`, `findAllItems()`, `findItemById()`, `createItem()`, `updateItem()`, `deleteItem()`, `batchDeleteItems()`, `getStats()`
+- **实现类**：`ResourceLibraryServiceImpl` 继承 `ServiceImpl<ResourceLibraryMapper, ResourceLibrary>` 并实现 `ResourceLibraryService` 接口
+
+#### 3. CourseLessonService
+- **接口方法**：`findByCourseId()`, `findById()`, `findByType()`, `create()`, `update()`, `delete()`, `reorder()`, `findSteps()`, `createStep()`, `updateStep()`, `deleteStep()`, `reorderSteps()`, `findCourseLessonsForTeacher()`
+- **实现类**：`CourseLessonServiceImpl` 继承 `ServiceImpl<CourseLessonMapper, CourseLesson>` 并实现 `CourseLessonService` 接口
+
+#### 4. CourseCollectionService
+- **接口方法**：`findTenantCollections()`, `getCollectionDetail()`, `pageCollections()`, `getPackagesByCollection()`, `createCollection()`, `setCollectionPackages()`, `updateCollection()`, `deleteCollection()`, `publishCollection()`, `archiveCollection()`, `republishCollection()`, `withdrawCollection()`, `submitCollection()`, `rejectCollection()`, `renewTenantCollection()`
+- **实现类**：`CourseCollectionServiceImpl` 继承 `ServiceImpl<CourseCollectionMapper, CourseCollection>` 并实现 `CourseCollectionService` 接口
+- **依赖注入**：注入 `CourseLessonService` 用于查询课程环节
+
+### 验证结果
+
+```bash
+export JAVA_HOME="/f/Java/jdk-17"
+mvn compile -DskipTests
+```
+
+**编译结果**：✅ BUILD SUCCESS
+
+### 影响范围
+
+- Controller 层引用保持不变（Spring 自动注入接口实现）
+- 其他服务层调用保持不变
+- 无数据库变更
+- 无 API 变更
+
+### 备注
+
+- `FileStorageService` 是纯工具类服务，不涉及数据库操作，无需继承 `IService`，保持当前结构即可
diff --git a/reading-platform-java/src/main/java/com/reading/platform/service/CourseCollectionService.java b/reading-platform-java/src/main/java/com/reading/platform/service/CourseCollectionService.java
index 07f6b78..d017e61 100644
--- a/reading-platform-java/src/main/java/com/reading/platform/service/CourseCollectionService.java
+++ b/reading-platform-java/src/main/java/com/reading/platform/service/CourseCollectionService.java
@@ -1,625 +1,93 @@
 package com.reading.platform.service;
 
-import com.alibaba.fastjson2.JSON;
-import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
 import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
-import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
-import com.reading.platform.common.enums.CourseStatus;
-import com.reading.platform.common.enums.TenantPackageStatus;
-import com.reading.platform.common.exception.BusinessException;
-import com.reading.platform.common.response.PageResult;
+import com.baomidou.mybatisplus.extension.service.IService;
 import com.reading.platform.dto.response.CourseCollectionResponse;
 import com.reading.platform.dto.response.CoursePackageResponse;
-import com.reading.platform.entity.CoursePackage;
 import com.reading.platform.entity.CourseCollection;
-import com.reading.platform.entity.CourseCollectionPackage;
-import com.reading.platform.entity.CoursePackageCourse;
-import com.reading.platform.entity.CourseLesson;
-import com.reading.platform.entity.TenantPackage;
-import com.reading.platform.mapper.CourseCollectionMapper;
-import com.reading.platform.mapper.CourseCollectionPackageMapper;
-import com.reading.platform.mapper.CoursePackageMapper;
-import com.reading.platform.mapper.CoursePackageCourseMapper;
-import com.reading.platform.mapper.TenantPackageMapper;
-import lombok.RequiredArgsConstructor;
-import lombok.extern.slf4j.Slf4j;
-import org.springframework.stereotype.Service;
-import org.springframework.transaction.annotation.Transactional;
-import org.springframework.util.StringUtils;
 
-import java.time.LocalDateTime;
-import java.util.ArrayList;
+import java.time.LocalDate;
 import java.util.List;
-import java.util.stream.Collectors;
 
 /**
- * 课程套餐服务（两层结构-最上层）
+ * 课程套餐服务接口（两层结构 - 最上层）
  */
-@Slf4j
-@Service
-@RequiredArgsConstructor
-public class CourseCollectionService extends ServiceImpl<CourseCollectionMapper, CourseCollection> {
-
-    private final CourseCollectionMapper collectionMapper;
-    private final CourseCollectionPackageMapper collectionPackageMapper;
-    private final CoursePackageMapper packageMapper;
-    private final TenantPackageMapper tenantPackageMapper;
-    private final CoursePackageCourseMapper packageCoursePackageMapper;
-    private final CoursePackageMapper courseMapper;
-    private final CourseLessonService courseLessonService;
+public interface CourseCollectionService extends IService<CourseCollection> {
 
     /**
      * 查询租户的课程套餐列表
      */
-    public List<CourseCollectionResponse> findTenantCollections(Long tenantId) {
-        log.info("查询租户课程套餐，tenantId={}", tenantId);
-
-        // 查询租户的课程套餐关联
-        List<TenantPackage> tenantPackages = tenantPackageMapper.selectList(
-                new LambdaQueryWrapper<TenantPackage>()
-                        .eq(TenantPackage::getTenantId, tenantId)
-                        .eq(TenantPackage::getStatus, TenantPackageStatus.ACTIVE.getCode())
-                        .isNotNull(TenantPackage::getCollectionId)
-                        .orderByDesc(TenantPackage::getCreatedAt)
-        );
-
-        log.info("查询到{}条租户套餐关联记录", tenantPackages.size());
-        for (TenantPackage tp : tenantPackages) {
-            log.info("  - collection_id: {}, start_date: {}, end_date: {}",
-                tp.getCollectionId(), tp.getStartDate(), tp.getEndDate());
-        }
-
-        // 获取套餐详情并转换为响应对象
-        List<CourseCollectionResponse> result = tenantPackages.stream()
-                .map(tp -> {
-                    CourseCollection collection = collectionMapper.selectById(tp.getCollectionId());
-                    if (collection == null) {
-                        log.warn("套餐不存在，collection_id={}", tp.getCollectionId());
-                        return null;
-                    }
-                    // 过滤下架状态的课程套餐
-                    if (CourseStatus.ARCHIVED.getCode().equals(collection.getStatus())) {
-                        log.warn("套餐已下架，collection_id={}", tp.getCollectionId());
-                        return null;
-                    }
-                    log.info("返回套餐: id={}, name={}, package_count={}",
-                        collection.getId(), collection.getName(), collection.getPackageCount());
-                    CourseCollectionResponse response = toResponse(collection);
-                    // 设置租户套餐的额外信息（如果有）
-                    response.setStartDate(tp.getStartDate());
-                    response.setEndDate(tp.getEndDate());
-                    return response;
-                })
-                .filter(r -> r != null)
-                .collect(Collectors.toList());
-
-        log.info("查询到{}个课程套餐", result.size());
-        return result;
-    }
+    List<CourseCollectionResponse> findTenantCollections(Long tenantId);
 
     /**
      * 获取课程套餐详情（包含课程包列表）
      */
-    public CourseCollectionResponse getCollectionDetail(Long collectionId) {
-        log.info("获取课程套餐详情，collectionId={}", collectionId);
-
-        CourseCollection collection = collectionMapper.selectById(collectionId);
-        if (collection == null) {
-            log.warn("课程套餐不存在，collectionId={}", collectionId);
-            return null;
-        }
-
-        return toResponse(collection);
-    }
+    CourseCollectionResponse getCollectionDetail(Long collectionId);
 
     /**
      * 分页查询课程套餐
      */
-    public Page<CourseCollectionResponse> pageCollections(Integer pageNum, Integer pageSize, String status) {
-        log.info("分页查询课程套餐，pageNum={}, pageSize={}, status={}", pageNum, pageSize, status);
-
-        LambdaQueryWrapper<CourseCollection> wrapper = new LambdaQueryWrapper<>();
-        if (StringUtils.hasText(status)) {
-            wrapper.eq(CourseCollection::getStatus, status);
-        }
-        wrapper.orderByDesc(CourseCollection::getCreatedAt);
-
-        Page<CourseCollection> page = collectionMapper.selectPage(
-                new Page<>(pageNum, pageSize),
-                wrapper
-        );
-
-        // 转换为响应对象
-        List<CourseCollectionResponse> responses = page.getRecords().stream()
-                .map(this::toResponse)
-                .collect(Collectors.toList());
-
-        Page<CourseCollectionResponse> result = new Page<>(page.getCurrent(), page.getSize(), page.getTotal());
-        result.setRecords(responses);
-        return result;
-    }
+    Page<CourseCollectionResponse> pageCollections(Integer pageNum, Integer pageSize, String status);
 
     /**
      * 获取课程套餐下的课程包列表
      */
-    public List<CoursePackageResponse> getPackagesByCollection(Long collectionId) {
-        log.info("获取课程套餐的课程包列表，collectionId={}", collectionId);
-
-        // 查询关联关系
-        List<CourseCollectionPackage> associations = collectionPackageMapper.selectList(
-                new LambdaQueryWrapper<CourseCollectionPackage>()
-                        .eq(CourseCollectionPackage::getCollectionId, collectionId)
-                        .orderByAsc(CourseCollectionPackage::getSortOrder)
-        );
-
-        if (associations.isEmpty()) {
-            return new ArrayList<>();
-        }
-
-        // 获取课程包详情
-        List<Long> packageIds = associations.stream()
-                .map(CourseCollectionPackage::getPackageId)
-                .collect(Collectors.toList());
-
-        List<CoursePackage> packages = packageMapper.selectList(
-                new LambdaQueryWrapper<CoursePackage>()
-                        .in(CoursePackage::getId, packageIds)
-                        .eq(CoursePackage::getStatus, CourseStatus.PUBLISHED.getCode())
-        );
-
-        // 转换为响应对象并设置排序号
-        List<CoursePackageResponse> result = packages.stream()
-                .map(pkg -> {
-                    CoursePackageResponse response = toPackageResponse(pkg);
-                    // 设置排序号
-                    associations.stream()
-                            .filter(a -> a.getPackageId().equals(pkg.getId()))
-                            .findFirst()
-                            .ifPresent(a -> response.setSortOrder(a.getSortOrder()));
-                    return response;
-                })
-                .collect(Collectors.toList());
-
-        log.info("查询到{}个课程包", result.size());
-        return result;
-    }
+    List<CoursePackageResponse> getPackagesByCollection(Long collectionId);
 
     /**
      * 创建课程套餐
      */
-    @Transactional(rollbackFor = Exception.class)
-    public CourseCollectionResponse createCollection(String name, String description, Long price,
-                                              Long discountPrice, String discountType, String[] gradeLevels) {
-        log.info("创建课程套餐，name={}", name);
-
-        CourseCollection collection = new CourseCollection();
-        collection.setName(name);
-        collection.setDescription(description);
-        collection.setPrice(price);
-        collection.setDiscountPrice(discountPrice);
-        collection.setDiscountType(discountType);
-        // 将数组转为 JSON 字符串存储到 JSON 字段
-        collection.setGradeLevels(JSON.toJSONString(gradeLevels));
-        collection.setPackageCount(0);
-        collection.setStatus(CourseStatus.DRAFT.getCode());
-
-        collectionMapper.insert(collection);
-
-        log.info("课程套餐创建成功，id={}", collection.getId());
-        return toResponse(collection);
-    }
+    CourseCollectionResponse createCollection(String name, String description, Long price,
+                                             Long discountPrice, String discountType, String[] gradeLevels);
 
     /**
      * 设置课程套餐的课程包
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void setCollectionPackages(Long collectionId, List<Long> packageIds) {
-        log.info("设置课程套餐的课程包，collectionId={}, packageCount={}", collectionId, packageIds.size());
-
-        // 验证课程套餐是否存在
-        CourseCollection collection = collectionMapper.selectById(collectionId);
-        if (collection == null) {
-            throw new BusinessException("课程套餐不存在");
-        }
-
-        // 去重：保持首次出现顺序，避免 uk_collection_package 唯一约束冲突
-        List<Long> distinctIds = packageIds.stream().distinct().collect(Collectors.toList());
-
-        // 验证课程包是否存在（应用层外键约束）
-        if (!distinctIds.isEmpty()) {
-            List<CoursePackage> packages = packageMapper.selectList(
-                    new LambdaQueryWrapper<CoursePackage>()
-                            .in(CoursePackage::getId, distinctIds)
-            );
-            if (packages.size() != distinctIds.size()) {
-                throw new BusinessException("存在无效的课程包 ID");
-            }
-        }
-
-        // 删除旧的关联
-        collectionPackageMapper.delete(
-                new LambdaQueryWrapper<CourseCollectionPackage>()
-                        .eq(CourseCollectionPackage::getCollectionId, collectionId)
-        );
-
-        // 创建新的关联
-        for (int i = 0; i < distinctIds.size(); i++) {
-            CourseCollectionPackage association = new CourseCollectionPackage();
-            association.setCollectionId(collectionId);
-            association.setPackageId(distinctIds.get(i));
-            association.setSortOrder(i + 1);
-            collectionPackageMapper.insert(association);
-        }
-
-        // 更新课程包数量（复用前面已验证的 collection 变量）
-        collection.setPackageCount(distinctIds.size());
-        collectionMapper.updateById(collection);
-
-        log.info("课程套餐的课程包设置完成");
-    }
+    void setCollectionPackages(Long collectionId, List<Long> packageIds);
 
     /**
      * 更新课程套餐
      */
-    @Transactional(rollbackFor = Exception.class)
-    public CourseCollectionResponse updateCollection(Long id, String name, String description, Long price,
-                                              Long discountPrice, String discountType, String[] gradeLevels) {
-        log.info("更新课程套餐，id={}", id);
-
-        CourseCollection collection = collectionMapper.selectById(id);
-        if (collection == null) {
-            throw new IllegalArgumentException("课程套餐不存在");
-        }
-
-        collection.setName(name);
-        collection.setDescription(description);
-        collection.setPrice(price);
-        collection.setDiscountPrice(discountPrice);
-        collection.setDiscountType(discountType);
-        // 将数组转为 JSON 字符串存储到 JSON 字段
-        collection.setGradeLevels(JSON.toJSONString(gradeLevels));
-
-        collectionMapper.updateById(collection);
-
-        log.info("课程套餐更新成功，id={}", id);
-        return toResponse(collection);
-    }
+    CourseCollectionResponse updateCollection(Long id, String name, String description, Long price,
+                                             Long discountPrice, String discountType, String[] gradeLevels);
 
     /**
      * 删除课程套餐
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void deleteCollection(Long id) {
-        log.info("删除课程套餐，id={}", id);
-
-        // 检查是否有租户正在使用此课程套餐
-        Long tenantCount = tenantPackageMapper.selectCount(
-                new LambdaQueryWrapper<TenantPackage>()
-                        .eq(TenantPackage::getCollectionId, id)
-                        .eq(TenantPackage::getStatus, TenantPackageStatus.ACTIVE)
-        );
-
-        if (tenantCount > 0) {
-            log.warn("删除课程套餐失败，有 {} 个租户正在使用此套餐，id={}", tenantCount, id);
-            throw new BusinessException("有 " + tenantCount + " 个租户正在使用此课程套餐，无法删除");
-        }
-
-        // 清理所有状态的租户套餐关联记录（包括非活跃状态）
-        List<TenantPackage> allTenantPackages = tenantPackageMapper.selectList(
-                new LambdaQueryWrapper<TenantPackage>()
-                        .eq(TenantPackage::getCollectionId, id)
-        );
-
-        if (!allTenantPackages.isEmpty()) {
-            tenantPackageMapper.delete(
-                    new LambdaQueryWrapper<TenantPackage>()
-                            .eq(TenantPackage::getCollectionId, id)
-            );
-            log.info("已清理 {} 条租户套餐关联记录", allTenantPackages.size());
-        }
-
-        // 删除课程套餐与课程包的关联关系
-        List<CourseCollectionPackage> collectionPackages = collectionPackageMapper.selectList(
-                new LambdaQueryWrapper<CourseCollectionPackage>()
-                        .eq(CourseCollectionPackage::getCollectionId, id)
-        );
-
-        if (!collectionPackages.isEmpty()) {
-            collectionPackageMapper.delete(
-                    new LambdaQueryWrapper<CourseCollectionPackage>()
-                            .eq(CourseCollectionPackage::getCollectionId, id)
-            );
-            log.info("已清理 {} 条课程包关联记录", collectionPackages.size());
-        }
-
-        // 删除课程套餐
-        collectionMapper.deleteById(id);
-
-        log.info("课程套餐删除成功，id={}", id);
-    }
+    void deleteCollection(Long id);
 
     /**
      * 发布课程套餐
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void publishCollection(Long id) {
-        log.info("发布课程套餐，id={}", id);
-
-        CourseCollection collection = collectionMapper.selectById(id);
-        if (collection == null) {
-            throw new IllegalArgumentException("课程套餐不存在");
-        }
-
-        collection.setStatus(CourseStatus.PUBLISHED.getCode());
-        collection.setPublishedAt(LocalDateTime.now());
-        collectionMapper.updateById(collection);
-
-        log.info("课程套餐发布成功，id={}", id);
-    }
+    void publishCollection(Long id);
 
     /**
      * 下架课程套餐
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void archiveCollection(Long id) {
-        log.info("下架课程套餐，id={}", id);
-
-        CourseCollection collection = collectionMapper.selectById(id);
-        if (collection == null) {
-            throw new IllegalArgumentException("课程套餐不存在");
-        }
-
-        collection.setStatus(CourseStatus.ARCHIVED.getCode());
-        collectionMapper.updateById(collection);
-
-        log.info("课程套餐下架成功，id={}", id);
-    }
+    void archiveCollection(Long id);
 
     /**
      * 重新发布课程套餐
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void republishCollection(Long id) {
-        log.info("重新发布课程套餐，id={}", id);
-
-        CourseCollection collection = collectionMapper.selectById(id);
-        if (collection == null) {
-            throw new IllegalArgumentException("课程套餐不存在");
-        }
-
-        collection.setStatus(CourseStatus.PUBLISHED.getCode());
-        collection.setPublishedAt(LocalDateTime.now());
-        collectionMapper.updateById(collection);
-
-        log.info("课程套餐重新发布成功，id={}", id);
-    }
+    void republishCollection(Long id);
 
     /**
      * 撤销审核
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void withdrawCollection(Long id) {
-        log.info("撤销课程套餐审核，id={}", id);
-
-        CourseCollection collection = collectionMapper.selectById(id);
-        if (collection == null) {
-            throw new IllegalArgumentException("课程套餐不存在");
-        }
-
-        collection.setStatus(CourseStatus.DRAFT.getCode());
-        collectionMapper.updateById(collection);
-
-        log.info("课程套餐审核撤销成功，id={}", id);
-    }
+    void withdrawCollection(Long id);
 
     /**
      * 提交课程套餐审核
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void submitCollection(Long id) {
-        log.info("提交课程套餐审核，id={}", id);
-
-        CourseCollection collection = collectionMapper.selectById(id);
-        if (collection == null) {
-            throw new IllegalArgumentException("课程套餐不存在");
-        }
-
-        // 检查是否包含课程包
-        if (collection.getPackageCount() == null || collection.getPackageCount() == 0) {
-            throw new BusinessException("课程套餐必须包含至少一个课程包");
-        }
-
-        collection.setStatus(CourseStatus.PENDING.getCode());
-        collection.setSubmittedAt(LocalDateTime.now());
-        collectionMapper.updateById(collection);
-
-        log.info("课程套餐提交审核成功，id={}", id);
-    }
+    void submitCollection(Long id);
 
     /**
      * 审核驳回课程套餐
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void rejectCollection(Long id, String comment) {
-        log.info("审核驳回课程套餐，id={}, comment={}", id, comment);
-
-        CourseCollection collection = collectionMapper.selectById(id);
-        if (collection == null) {
-            throw new IllegalArgumentException("课程套餐不存在");
-        }
-
-        collection.setStatus(CourseStatus.REJECTED.getCode());
-        collection.setReviewedAt(LocalDateTime.now());
-        collection.setReviewComment(comment);
-        collectionMapper.updateById(collection);
-
-        log.info("课程套餐审核驳回成功，id={}", id);
-    }
+    void rejectCollection(Long id, String comment);
 
     /**
      * 续费租户课程套餐
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void renewTenantCollection(Long tenantId, Long collectionId, java.time.LocalDate endDate, Long pricePaid) {
-        log.info("续费租户课程套餐，tenantId={}, collectionId={}, endDate={}, pricePaid={}", tenantId, collectionId, endDate, pricePaid);
-
-        // 查询现有租户套餐关联
-        List<TenantPackage> existingPackages = tenantPackageMapper.selectList(
-                new LambdaQueryWrapper<TenantPackage>()
-                        .eq(TenantPackage::getTenantId, tenantId)
-                        .eq(TenantPackage::getCollectionId, collectionId)
-        );
-
-        if (!existingPackages.isEmpty()) {
-            // 更新现有记录
-            TenantPackage existing = existingPackages.get(0);
-            existing.setEndDate(endDate);
-            existing.setStatus(TenantPackageStatus.ACTIVE);
-            if (pricePaid != null) {
-                existing.setPricePaid(pricePaid);
-            }
-            existing.setUpdatedAt(LocalDateTime.now());
-            tenantPackageMapper.updateById(existing);
-            log.info("租户课程套餐续费成功，tenantId={}, collectionId={}", tenantId, collectionId);
-        } else {
-            // 查询课程套餐信息
-            CourseCollection collection = collectionMapper.selectById(collectionId);
-            if (collection == null) {
-                throw new IllegalArgumentException("课程套餐不存在");
-            }
-
-            // 创建新记录
-            TenantPackage tp = new TenantPackage();
-            tp.setTenantId(tenantId);
-            tp.setCollectionId(collectionId);
-            tp.setStartDate(java.time.LocalDate.now());
-            tp.setEndDate(endDate);
-            tp.setStatus(TenantPackageStatus.ACTIVE);
-            tp.setPricePaid(pricePaid != null ? pricePaid :
-                (collection.getDiscountPrice() != null ? collection.getDiscountPrice() : collection.getPrice()));
-            tp.setCreatedAt(LocalDateTime.now());
-            tenantPackageMapper.insert(tp);
-            log.info("租户课程套餐新办成功，tenantId={}, collectionId={}", tenantId, collectionId);
-        }
-    }
-
-    /**
-     * 解析适用年级：数据库存储为 JSON 数组 ["小班","中班","大班"]，需正确解析
-     */
-    private String[] parseGradeLevels(String gradeLevels) {
-        if (!StringUtils.hasText(gradeLevels)) {
-            return new String[0];
-        }
-        try {
-            if (gradeLevels.trim().startsWith("[")) {
-                return JSON.parseArray(gradeLevels, String.class).toArray(new String[0]);
-            }
-            // 兼容旧数据：逗号分隔格式
-            return gradeLevels.split(",");
-        } catch (Exception e) {
-            log.warn("解析 gradeLevels 失败: {}", gradeLevels, e);
-            return new String[0];
-        }
-    }
-
-    /**
-     * 转换为响应对象
-     */
-    private CourseCollectionResponse toResponse(CourseCollection collection) {
-        // 获取课程包列表
-        List<CourseCollectionResponse.CoursePackageItem> packages = getPackagesByCollection(collection.getId()).stream()
-                .map(pkg -> {
-                    CourseCollectionResponse.CoursePackageItem item = new CourseCollectionResponse.CoursePackageItem();
-                    item.setId(pkg.getId());
-                    item.setName(pkg.getName());
-                    item.setDescription(pkg.getDescription());
-                    item.setGradeLevels(pkg.getGradeLevels() != null ? pkg.getGradeLevels() : new String[0]);
-                    item.setCourseCount(pkg.getCourseCount() != null ? pkg.getCourseCount() : 0);
-                    item.setSortOrder(pkg.getSortOrder());
-                    return item;
-                })
-                .collect(Collectors.toList());
-
-        return CourseCollectionResponse.builder()
-                .id(collection.getId())
-                .name(collection.getName())
-                .description(collection.getDescription())
-                .price(collection.getPrice())
-                .discountPrice(collection.getDiscountPrice())
-                .discountType(collection.getDiscountType())
-                .gradeLevels(parseGradeLevels(collection.getGradeLevels()))
-                .packageCount(collection.getPackageCount())
-                .status(collection.getStatus())
-                .submittedAt(collection.getSubmittedAt())
-                .submittedBy(collection.getSubmittedBy())
-                .reviewedAt(collection.getReviewedAt())
-                .reviewedBy(collection.getReviewedBy())
-                .reviewComment(collection.getReviewComment())
-                .publishedAt(collection.getPublishedAt())
-                .createdAt(collection.getCreatedAt())
-                .updatedAt(collection.getUpdatedAt())
-                .packages(packages)
-                .build();
-    }
-
-    /**
-     * 转换为课程包响应对象（包含课程列表和排课计划参考）
-     */
-    private CoursePackageResponse toPackageResponse(CoursePackage pkg) {
-        // 解析 gradeTags（CoursePackage 使用 gradeTags）
-        String[] gradeLevelsArray = new String[0];
-        if (pkg.getGradeTags() != null && !pkg.getGradeTags().isEmpty()) {
-            try {
-                // gradeTags 是 JSON 数组格式，尝试解析
-                if (pkg.getGradeTags().startsWith("[")) {
-                    gradeLevelsArray = com.alibaba.fastjson2.JSON.parseArray(pkg.getGradeTags(), String.class).toArray(new String[0]);
-                } else {
-                    gradeLevelsArray = pkg.getGradeTags().split(",");
-                }
-            } catch (Exception e) {
-                gradeLevelsArray = new String[0];
-            }
-        }
-
-        List<CoursePackageResponse.CoursePackageCourseItem> courseItems = new ArrayList<>();
-
-        // 查询课程包关联的课程环节
-        List<CourseLesson> lessons = courseLessonService.findByCourseId(pkg.getId());
-
-        if (!lessons.isEmpty()) {
-            courseItems = lessons.stream()
-                    .map(lesson -> {
-                        CoursePackageResponse.CoursePackageCourseItem item = new CoursePackageResponse.CoursePackageCourseItem();
-                        item.setId(lesson.getId());
-                        item.setName(lesson.getName());
-                        item.setGradeLevel(null); // 课程环节没有年级字段
-                        item.setSortOrder(lesson.getSortOrder());
-                        item.setScheduleRefData(pkg.getScheduleRefData());
-                        item.setLessonType(lesson.getLessonType());
-                        return item;
-                    })
-                    .collect(Collectors.toList());
-        }
-
-        return CoursePackageResponse.builder()
-                .id(pkg.getId())
-                .name(pkg.getName())
-                .description(pkg.getDescription())
-                .price(null) // CoursePackage 没有价格字段
-                .discountPrice(null)
-                .discountType(null)
-                .gradeLevels(gradeLevelsArray)
-                .courseCount(lessons.size()) // 使用课程环节数量
-                .status(pkg.getStatus())
-                .submittedAt(pkg.getSubmittedAt())
-                .submittedBy(pkg.getSubmittedBy())
-                .reviewedAt(pkg.getReviewedAt())
-                .reviewedBy(pkg.getReviewedBy())
-                .reviewComment(pkg.getReviewComment())
-                .publishedAt(pkg.getPublishedAt())
-                .createdAt(pkg.getCreatedAt())
-                .updatedAt(pkg.getUpdatedAt())
-                .courses(courseItems)
-                .build();
-    }
+    void renewTenantCollection(Long tenantId, Long collectionId, LocalDate endDate, Long pricePaid);
 }
diff --git a/reading-platform-java/src/main/java/com/reading/platform/service/CourseLessonService.java b/reading-platform-java/src/main/java/com/reading/platform/service/CourseLessonService.java
index 4610006..3c77094 100644
--- a/reading-platform-java/src/main/java/com/reading/platform/service/CourseLessonService.java
+++ b/reading-platform-java/src/main/java/com/reading/platform/service/CourseLessonService.java
@@ -1,417 +1,87 @@
 package com.reading.platform.service;
 
-import com.alibaba.fastjson2.JSON;
-import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
-import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
-import com.reading.platform.common.enums.TenantPackageStatus;
-import com.reading.platform.common.exception.BusinessException;
-import com.reading.platform.entity.*;
-import com.reading.platform.mapper.*;
-import com.reading.platform.mapper.TenantCourseMapper;
-import lombok.RequiredArgsConstructor;
-import lombok.extern.slf4j.Slf4j;
-import org.springframework.stereotype.Service;
-import org.springframework.transaction.annotation.Transactional;
+import com.baomidou.mybatisplus.extension.service.IService;
+import com.reading.platform.entity.CourseLesson;
+import com.reading.platform.entity.LessonStep;
 
-import java.time.LocalDateTime;
 import java.util.List;
 
 /**
- * 课程环节服务
+ * 课程环节服务接口
  */
-@Slf4j
-@Service
-@RequiredArgsConstructor
-public class CourseLessonService extends ServiceImpl<CourseLessonMapper, CourseLesson> {
-
-    private final CourseLessonMapper courseLessonMapper;
-    private final LessonStepMapper lessonStepMapper;
-    private final LessonStepResourceMapper lessonStepResourceMapper;
-    private final TenantCourseMapper tenantCourseMapper;
-    private final TenantPackageMapper tenantPackageMapper;
+public interface CourseLessonService extends IService<CourseLesson> {
 
     /**
      * 查询课程的所有环节
      */
-    public List<CourseLesson> findByCourseId(Long courseId) {
-        log.info("查询课程的所有环节，courseId={}", courseId);
-        List<CourseLesson> result = courseLessonMapper.selectList(
-                new LambdaQueryWrapper<CourseLesson>()
-                        .eq(CourseLesson::getCourseId, courseId)
-                        .orderByAsc(CourseLesson::getSortOrder)
-        );
-        log.info("查询课程环节成功，courseId={}, count={}", courseId, result.size());
-        return result;
-    }
+    List<CourseLesson> findByCourseId(Long courseId);
 
     /**
      * 查询课程环节详情
      */
-    public CourseLesson findById(Long id) {
-        log.info("查询课程环节详情，id={}", id);
-        CourseLesson lesson = courseLessonMapper.selectById(id);
-        if (lesson == null) {
-            log.warn("课程环节不存在，id={}", id);
-            throw new BusinessException("课程环节不存在");
-        }
-        return lesson;
-    }
+    CourseLesson findById(Long id);
 
     /**
      * 按类型查询课程环节
      */
-    public CourseLesson findByType(Long courseId, String lessonType) {
-        log.info("按类型查询课程环节，courseId={}, lessonType={}", courseId, lessonType);
-        CourseLesson result = courseLessonMapper.selectOne(
-                new LambdaQueryWrapper<CourseLesson>()
-                        .eq(CourseLesson::getCourseId, courseId)
-                        .eq(CourseLesson::getLessonType, lessonType)
-        );
-        if (result != null) {
-            log.info("查询课程环节成功，courseId={}, lessonType={}, id={}", courseId, lessonType, result.getId());
-        }
-        return result;
-    }
+    CourseLesson findByType(Long courseId, String lessonType);
 
     /**
      * 创建课程环节
      */
-    @Transactional(rollbackFor = Exception.class)
-    public CourseLesson create(Long courseId, String lessonType, String name, String description,
-                               Integer duration, String videoPath, String videoName,
-                               String pptPath, String pptName, String pdfPath, String pdfName,
-                               String objectives, String preparation, String extension,
-                               String reflection, String assessmentData, Boolean useTemplate) {
-        log.info("创建课程环节，courseId={}, lessonType={}, name={}", courseId, lessonType, name);
-        // 检查是否已存在相同类型的课程
-        CourseLesson existing = findByType(courseId, lessonType);
-        if (existing != null) {
-            log.warn("创建课程环节失败，已存在相同类型的课程环节，courseId={}, lessonType={}", courseId, lessonType);
-            throw new BusinessException("该课程包已存在 " + lessonType + " 类型的课程");
-        }
-
-        // 获取最大排序号
-        Integer maxSortOrder = courseLessonMapper.selectList(
-                        new LambdaQueryWrapper<CourseLesson>()
-                                .eq(CourseLesson::getCourseId, courseId)
-                ).stream()
-                .map(CourseLesson::getSortOrder)
-                .max(Integer::compareTo)
-                .orElse(0);
-
-        CourseLesson lesson = new CourseLesson();
-        lesson.setCourseId(courseId);
-        lesson.setLessonType(lessonType);
-        lesson.setName(name);
-        lesson.setDescription(description);
-        lesson.setDuration(duration);
-        lesson.setVideoPath(videoPath);
-        lesson.setVideoName(videoName);
-        lesson.setPptPath(pptPath);
-        lesson.setPptName(pptName);
-        lesson.setPdfPath(pdfPath);
-        lesson.setPdfName(pdfName);
-        lesson.setObjectives(objectives);
-        lesson.setPreparation(preparation);
-        lesson.setExtension(extension);
-        lesson.setReflection(reflection);
-        // 确保 assessment_data 为有效 JSON，MySQL JSON 列不接受纯文本
-        lesson.setAssessmentData(toValidJsonOrNull(assessmentData));
-        lesson.setUseTemplate(useTemplate);
-        lesson.setSortOrder(maxSortOrder + 1);
-        lesson.setCreatedAt(LocalDateTime.now());
-
-        courseLessonMapper.insert(lesson);
-        log.info("课程环节创建成功，id={}, courseId={}, lessonType={}", lesson.getId(), courseId, lessonType);
-        return lesson;
-    }
+    CourseLesson create(Long courseId, String lessonType, String name, String description,
+                       Integer duration, String videoPath, String videoName,
+                       String pptPath, String pptName, String pdfPath, String pdfName,
+                       String objectives, String preparation, String extension,
+                       String reflection, String assessmentData, Boolean useTemplate);
 
     /**
      * 更新课程环节
      */
-    @Transactional(rollbackFor = Exception.class)
-    public CourseLesson update(Long id, String name, String description, Integer duration,
-                               String videoPath, String videoName, String pptPath, String pptName,
-                               String pdfPath, String pdfName, String objectives, String preparation,
-                               String extension, String reflection, String assessmentData, Boolean useTemplate) {
-        log.info("更新课程环节，id={}", id);
-        CourseLesson lesson = courseLessonMapper.selectById(id);
-        if (lesson == null) {
-            log.warn("课程环节不存在，id={}", id);
-            throw new BusinessException("课程不存在");
-        }
-
-        if (name != null) {
-            lesson.setName(name);
-        }
-        if (description != null) {
-            lesson.setDescription(description);
-        }
-        if (duration != null) {
-            lesson.setDuration(duration);
-        }
-        if (videoPath != null) {
-            lesson.setVideoPath(videoPath);
-        }
-        if (videoName != null) {
-            lesson.setVideoName(videoName);
-        }
-        if (pptPath != null) {
-            lesson.setPptPath(pptPath);
-        }
-        if (pptName != null) {
-            lesson.setPptName(pptName);
-        }
-        if (pdfPath != null) {
-            lesson.setPdfPath(pdfPath);
-        }
-        if (pdfName != null) {
-            lesson.setPdfName(pdfName);
-        }
-        if (objectives != null) {
-            lesson.setObjectives(objectives);
-        }
-        if (preparation != null) {
-            lesson.setPreparation(preparation);
-        }
-        if (extension != null) {
-            lesson.setExtension(extension);
-        }
-        if (reflection != null) {
-            lesson.setReflection(reflection);
-        }
-        if (assessmentData != null) {
-            lesson.setAssessmentData(toValidJsonOrNull(assessmentData));
-        }
-        if (useTemplate != null) {
-            lesson.setUseTemplate(useTemplate);
-        }
-
-        lesson.setUpdatedAt(LocalDateTime.now());
-        courseLessonMapper.updateById(lesson);
-        log.info("课程环节更新成功，id={}", id);
-        return lesson;
-    }
+    CourseLesson update(Long id, String name, String description, Integer duration,
+                       String videoPath, String videoName, String pptPath, String pptName,
+                       String pdfPath, String pdfName, String objectives, String preparation,
+                       String extension, String reflection, String assessmentData, Boolean useTemplate);
 
     /**
      * 删除课程环节
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void delete(Long id) {
-        log.info("删除课程环节，id={}", id);
-        CourseLesson lesson = courseLessonMapper.selectById(id);
-        if (lesson == null) {
-            log.warn("课程环节不存在，id={}", id);
-            throw new BusinessException("课程不存在");
-        }
-
-        courseLessonMapper.deleteById(id);
-        log.info("课程环节删除成功，id={}", id);
-    }
+    void delete(Long id);
 
     /**
      * 重新排序课程环节
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void reorder(Long courseId, List<Long> lessonIds) {
-        log.info("重新排序课程环节，courseId={}, count={}", courseId, lessonIds.size());
-        for (int i = 0; i < lessonIds.size(); i++) {
-            CourseLesson lesson = courseLessonMapper.selectById(lessonIds.get(i));
-            if (lesson != null && lesson.getCourseId().equals(courseId)) {
-                lesson.setSortOrder(i + 1);
-                courseLessonMapper.updateById(lesson);
-            }
-        }
-        log.info("课程环节重新排序成功，courseId={}", courseId);
-    }
+    void reorder(Long courseId, List<Long> lessonIds);
 
     /**
      * 查询课程环节的教学环节
      */
-    public List<LessonStep> findSteps(Long lessonId) {
-        log.info("查询课程环节的教学环节，lessonId={}", lessonId);
-        List<LessonStep> result = lessonStepMapper.selectList(
-                new LambdaQueryWrapper<LessonStep>()
-                        .eq(LessonStep::getLessonId, lessonId)
-                        .orderByAsc(LessonStep::getSortOrder)
-        );
-        log.info("查询教学环节成功，lessonId={}, count={}", lessonId, result.size());
-        return result;
-    }
+    List<LessonStep> findSteps(Long lessonId);
 
     /**
      * 创建教学环节
      */
-    @Transactional(rollbackFor = Exception.class)
-    public LessonStep createStep(Long lessonId, String name, String content, Integer duration,
-                                 String objective, List<Long> resourceIds) {
-        log.info("创建教学环节，lessonId={}, name={}", lessonId, name);
-        // 获取最大排序号
-        Integer maxSortOrder = lessonStepMapper.selectList(
-                        new LambdaQueryWrapper<LessonStep>()
-                                .eq(LessonStep::getLessonId, lessonId)
-                ).stream()
-                .map(LessonStep::getSortOrder)
-                .max(Integer::compareTo)
-                .orElse(0);
-
-        LessonStep step = new LessonStep();
-        step.setLessonId(lessonId);
-        step.setName(name);
-        step.setContent(content);
-        step.setDuration(duration != null ? duration : 5);
-        step.setObjective(objective);
-        step.setResourceIds(resourceIds != null ? resourceIds.toString() : null);
-        step.setSortOrder(maxSortOrder + 1);
-        step.setCreatedAt(LocalDateTime.now());
-
-        lessonStepMapper.insert(step);
-
-        // 创建环节资源关联
-        if (resourceIds != null && !resourceIds.isEmpty()) {
-            for (int i = 0; i < resourceIds.size(); i++) {
-                LessonStepResource lsr = new LessonStepResource();
-                lsr.setStepId(step.getId());
-                lsr.setResourceId(resourceIds.get(i));
-                lsr.setSortOrder(i);
-                lessonStepResourceMapper.insert(lsr);
-            }
-        }
-
-        log.info("教学环节创建成功，id={}, lessonId={}", step.getId(), lessonId);
-        return step;
-    }
+    LessonStep createStep(Long lessonId, String name, String content, Integer duration,
+                         String objective, List<Long> resourceIds);
 
     /**
      * 更新教学环节
      */
-    @Transactional(rollbackFor = Exception.class)
-    public LessonStep updateStep(Long stepId, String name, String content, Integer duration,
-                                 String objective, List<Long> resourceIds) {
-        log.info("更新教学环节，stepId={}", stepId);
-        LessonStep step = lessonStepMapper.selectById(stepId);
-        if (step == null) {
-            log.warn("教学环节不存在，stepId={}", stepId);
-            throw new BusinessException("教学环节不存在");
-        }
-
-        if (name != null) {
-            step.setName(name);
-        }
-        if (content != null) {
-            step.setContent(content);
-        }
-        if (duration != null) {
-            step.setDuration(duration);
-        }
-        if (objective != null) {
-            step.setObjective(objective);
-        }
-        if (resourceIds != null) {
-            step.setResourceIds(resourceIds.toString());
-
-            // 删除旧的资源关联
-            lessonStepResourceMapper.delete(
-                    new LambdaQueryWrapper<LessonStepResource>()
-                            .eq(LessonStepResource::getStepId, stepId)
-            );
-
-            // 创建新的资源关联
-            for (int i = 0; i < resourceIds.size(); i++) {
-                LessonStepResource lsr = new LessonStepResource();
-                lsr.setStepId(stepId);
-                lsr.setResourceId(resourceIds.get(i));
-                lsr.setSortOrder(i);
-                lessonStepResourceMapper.insert(lsr);
-            }
-        }
-
-        step.setUpdatedAt(LocalDateTime.now());
-        lessonStepMapper.updateById(step);
-        log.info("教学环节更新成功，stepId={}", stepId);
-        return step;
-    }
+    LessonStep updateStep(Long stepId, String name, String content, Integer duration,
+                         String objective, List<Long> resourceIds);
 
     /**
      * 删除教学环节
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void deleteStep(Long stepId) {
-        log.info("删除教学环节，stepId={}", stepId);
-        lessonStepMapper.deleteById(stepId);
-        log.info("教学环节删除成功，stepId={}", stepId);
-    }
+    void deleteStep(Long stepId);
 
     /**
      * 重新排序教学环节
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void reorderSteps(Long lessonId, List<Long> stepIds) {
-        log.info("重新排序教学环节，lessonId={}, count={}", lessonId, stepIds.size());
-        for (int i = 0; i < stepIds.size(); i++) {
-            LessonStep step = lessonStepMapper.selectById(stepIds.get(i));
-            if (step != null && step.getLessonId().equals(lessonId)) {
-                step.setSortOrder(i + 1);
-                lessonStepMapper.updateById(step);
-            }
-        }
-        log.info("教学环节重新排序成功，lessonId={}", lessonId);
-    }
-
-    /**
-     * 将 assessmentData 转为 MySQL JSON 列可接受的有效 JSON。
-     * 空值返回 null；已是有效 JSON 则原样返回；否则包装为 JSON 字符串。
-     */
-    private String toValidJsonOrNull(String assessmentData) {
-        if (assessmentData == null || assessmentData.isEmpty()) {
-            return null;
-        }
-        String trimmed = assessmentData.trim();
-        if (trimmed.isEmpty()) {
-            return null;
-        }
-        // 已是有效 JSON（对象或数组）则直接使用
-        if ((trimmed.startsWith("{") && trimmed.endsWith("}")) || (trimmed.startsWith("[") && trimmed.endsWith("]"))) {
-            try {
-                JSON.parse(trimmed);
-                return trimmed;
-            } catch (Exception ignored) {
-                // 解析失败，当作普通文本处理
-            }
-        }
-        // 普通文本包装为 JSON 字符串
-        return JSON.toJSONString(assessmentData);
-    }
+    void reorderSteps(Long lessonId, List<Long> stepIds);
 
     /**
      * 查询教师的课程环节（带权限检查）
      */
-    public List<CourseLesson> findCourseLessonsForTeacher(Long courseId, Long tenantId) {
-        log.info("查询教师的课程环节，courseId={}, tenantId={}", courseId, tenantId);
-        // 检查租户是否有权限访问该课程
-        TenantCourse tenantCourse = tenantCourseMapper.selectOne(
-                new LambdaQueryWrapper<TenantCourse>()
-                        .eq(TenantCourse::getTenantId, tenantId)
-                        .eq(TenantCourse::getCourseId, courseId)
-                        .eq(TenantCourse::getEnabled, 1)
-        );
-
-        if (tenantCourse == null) {
-            // 检查是否通过套餐授权
-            Long count = tenantPackageMapper.selectCount(
-                    new LambdaQueryWrapper<TenantPackage>()
-                            .eq(TenantPackage::getTenantId, tenantId)
-                            .eq(TenantPackage::getStatus, TenantPackageStatus.ACTIVE)
-            );
-
-            if (count == 0) {
-                log.warn("无权访问该课程，courseId={}, tenantId={}", courseId, tenantId);
-                throw new BusinessException("无权访问该课程");
-            }
-        }
-
-        List<CourseLesson> result = findByCourseId(courseId);
-        log.info("查询教师的课程环节成功，courseId={}, count={}", courseId, result.size());
-        return result;
-    }
+    List<CourseLesson> findCourseLessonsForTeacher(Long courseId, Long tenantId);
 }
diff --git a/reading-platform-java/src/main/java/com/reading/platform/service/ResourceLibraryService.java b/reading-platform-java/src/main/java/com/reading/platform/service/ResourceLibraryService.java
index 14a2357..dc290e3 100644
--- a/reading-platform-java/src/main/java/com/reading/platform/service/ResourceLibraryService.java
+++ b/reading-platform-java/src/main/java/com/reading/platform/service/ResourceLibraryService.java
@@ -1,271 +1,81 @@
 package com.reading.platform.service;
 
-import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
 import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
-import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
-import com.reading.platform.common.exception.BusinessException;
+import com.baomidou.mybatisplus.extension.service.IService;
 import com.reading.platform.entity.ResourceItem;
 import com.reading.platform.entity.ResourceLibrary;
-import com.reading.platform.mapper.ResourceItemMapper;
-import com.reading.platform.mapper.ResourceLibraryMapper;
-import lombok.RequiredArgsConstructor;
-import lombok.extern.slf4j.Slf4j;
-import org.springframework.stereotype.Service;
 
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
 /**
- * 资源库服务
+ * 资源库服务接口
  */
-@Slf4j
-@Service
-@RequiredArgsConstructor
-public class ResourceLibraryService extends ServiceImpl<ResourceLibraryMapper, ResourceLibrary> {
-
-    private final ResourceLibraryMapper libraryMapper;
-    private final ResourceItemMapper itemMapper;
+public interface ResourceLibraryService extends IService<ResourceLibrary> {
 
     /**
      * 分页查询资源库
      */
-    public Page<ResourceLibrary> findAllLibraries(String libraryType, String keyword, Integer page, Integer pageSize) {
-        log.info("查询资源库列表，libraryType={}, keyword={}, page={}, pageSize={}", libraryType, keyword, page, pageSize);
-        Page<ResourceLibrary> pageParam = new Page<>(page, pageSize);
-        LambdaQueryWrapper<ResourceLibrary> wrapper = new LambdaQueryWrapper<>();
-
-        if (libraryType != null && !libraryType.isEmpty()) {
-            wrapper.eq(ResourceLibrary::getLibraryType, libraryType);
-        }
-
-        if (keyword != null && !keyword.isEmpty()) {
-            wrapper.like(ResourceLibrary::getName, keyword);
-        }
-
-        wrapper.orderByDesc(ResourceLibrary::getCreatedAt);
-
-        Page<ResourceLibrary> result = libraryMapper.selectPage(pageParam, wrapper);
-        log.info("查询资源库列表成功，总数={}", result.getTotal());
-        return result;
-    }
+    Page<ResourceLibrary> findAllLibraries(String libraryType, String keyword, Integer page, Integer pageSize);
 
     /**
      * 查询资源库详情
      */
-    public ResourceLibrary findLibraryById(String id) {
-        log.info("查询资源库详情，id={}", id);
-        ResourceLibrary library = libraryMapper.selectById(id);
-        if (library == null) {
-            log.warn("资源库不存在，id={}", id);
-            throw new BusinessException("资源库不存在");
-        }
-        return library;
-    }
+    ResourceLibrary findLibraryById(String id);
 
     /**
      * 查询资源库（不存在时返回 null）
      */
-    public ResourceLibrary findLibraryByIdOrNull(String id) {
-        if (id == null || id.isEmpty()) return null;
-        return libraryMapper.selectById(id);
-    }
+    ResourceLibrary findLibraryByIdOrNull(String id);
 
     /**
      * 创建资源库
      */
-    public ResourceLibrary createLibrary(String name, String type, String description, String tenantId) {
-        log.info("创建资源库，name={}, type={}, tenantId={}", name, type, tenantId);
-        ResourceLibrary library = new ResourceLibrary();
-        library.setName(name);
-        library.setLibraryType(type);
-        library.setDescription(description);
-        library.setTenantId(tenantId);
-        library.setStatus("ACTIVE");
-        library.setSortOrder(0);
-
-        libraryMapper.insert(library);
-        log.info("资源库创建成功，id={}", library.getId());
-        return library;
-    }
+    ResourceLibrary createLibrary(String name, String type, String description, String tenantId);
 
     /**
      * 更新资源库
      */
-    public ResourceLibrary updateLibrary(String id, String name, String description) {
-        log.info("更新资源库，id={}, name={}, description={}", id, name, description);
-        ResourceLibrary library = libraryMapper.selectById(id);
-        if (library == null) {
-            log.warn("资源库不存在，id={}", id);
-            throw new BusinessException("资源库不存在");
-        }
-
-        if (name != null) {
-            library.setName(name);
-        }
-        if (description != null) {
-            library.setDescription(description);
-        }
-
-        libraryMapper.updateById(library);
-        log.info("资源库更新成功，id={}", id);
-        return library;
-    }
+    ResourceLibrary updateLibrary(String id, String name, String description);
 
     /**
      * 删除资源库
      */
-    public void deleteLibrary(String id) {
-        log.info("删除资源库，id={}", id);
-        // 先删除该资源库下的所有资源项
-        LambdaQueryWrapper<ResourceItem> wrapper = new LambdaQueryWrapper<>();
-        wrapper.eq(ResourceItem::getLibraryId, id);
-        itemMapper.delete(wrapper);
-
-        libraryMapper.deleteById(id);
-        log.info("资源库删除成功，id={}", id);
-    }
+    void deleteLibrary(String id);
 
     /**
      * 分页查询资源项目
      */
-    public Page<ResourceItem> findAllItems(String libraryId, String fileType, String keyword, Integer page, Integer pageSize) {
-        log.info("查询资源项目列表，libraryId={}, fileType={}, keyword={}, page={}, pageSize={}", libraryId, fileType, keyword, page, pageSize);
-        Page<ResourceItem> pageParam = new Page<>(page, pageSize);
-        LambdaQueryWrapper<ResourceItem> wrapper = new LambdaQueryWrapper<>();
-
-        if (libraryId != null && !libraryId.isEmpty()) {
-            wrapper.eq(ResourceItem::getLibraryId, libraryId);
-        }
-
-        if (fileType != null && !fileType.isEmpty()) {
-            wrapper.eq(ResourceItem::getFileType, fileType);
-        }
-
-        if (keyword != null && !keyword.isEmpty()) {
-            wrapper.and(w -> w.like(ResourceItem::getTitle, keyword)
-                    .or()
-                    .like(ResourceItem::getDescription, keyword));
-        }
-
-        wrapper.orderByDesc(ResourceItem::getCreatedAt);
-
-        Page<ResourceItem> result = itemMapper.selectPage(pageParam, wrapper);
-        log.info("查询资源项目列表成功，总数={}", result.getTotal());
-        return result;
-    }
+    Page<ResourceItem> findAllItems(String libraryId, String fileType, String keyword, Integer page, Integer pageSize);
 
     /**
      * 查询资源项目详情
      */
-    public ResourceItem findItemById(String id) {
-        log.info("查询资源项目详情，id={}", id);
-        ResourceItem item = itemMapper.selectById(id);
-        if (item == null) {
-            log.warn("资源项目不存在，id={}", id);
-            throw new BusinessException("资源项目不存在");
-        }
-        return item;
-    }
+    ResourceItem findItemById(String id);
 
     /**
      * 创建资源项目（数字资源）
      */
-    public ResourceItem createItem(String libraryId, String title, String fileType, String filePath,
-                                   Long fileSize, String description, String tags, String tenantId) {
-        log.info("创建资源项目，libraryId={}, title={}, fileType={}, fileSize={}, tenantId={}", libraryId, title, fileType, fileSize, tenantId);
-        ResourceItem item = new ResourceItem();
-        item.setId(null); // 确保由数据库 AUTO_INCREMENT 生成，避免主键冲突
-        item.setLibraryId(libraryId); // 目标资源库 ID
-        item.setTitle(title);
-        item.setName(title); // 数据库 name 字段 NOT NULL，与 title 保持一致
-        item.setDescription(description);
-        item.setFileType(fileType);
-        item.setFilePath(filePath);
-        item.setFileSize(fileSize);
-        item.setTags(tags);
-        item.setSortOrder(0);
-        item.setTenantId(tenantId);
-        item.setStatus("ACTIVE");
-
-        itemMapper.insert(item);
-        log.info("资源项目创建成功，id={}", item.getId());
-        return item;
-    }
+    ResourceItem createItem(String libraryId, String title, String fileType, String filePath,
+                           Long fileSize, String description, String tags, String tenantId);
 
     /**
      * 更新资源项目（数字资源）
      */
-    public ResourceItem updateItem(String id, String title, String description, String tags) {
-        log.info("更新资源项目，id={}, title={}, description={}, tags={}", id, title, description, tags);
-        ResourceItem item = itemMapper.selectById(id);
-        if (item == null) {
-            log.warn("资源项目不存在，id={}", id);
-            throw new BusinessException("资源项目不存在");
-        }
-
-        if (title != null) {
-            item.setTitle(title);
-        }
-        if (description != null) {
-            item.setDescription(description);
-        }
-        if (tags != null) {
-            item.setTags(tags);
-        }
-
-        itemMapper.updateById(item);
-        log.info("资源项目更新成功，id={}", id);
-        return item;
-    }
+    ResourceItem updateItem(String id, String title, String description, String tags);
 
     /**
      * 删除资源项目
      */
-    public void deleteItem(String id) {
-        log.info("删除资源项目，id={}", id);
-        itemMapper.deleteById(id);
-        log.info("资源项目删除成功，id={}", id);
-    }
+    void deleteItem(String id);
 
     /**
      * 批量删除资源项目
      */
-    public void batchDeleteItems(List<String> ids) {
-        log.info("批量删除资源项目，ids={}", ids);
-        itemMapper.deleteBatchIds(ids);
-        log.info("批量删除资源项目成功，数量={}", ids.size());
-    }
+    void batchDeleteItems(List<String> ids);
 
     /**
      * 获取统计数据
      */
-    public Map<String, Object> getStats() {
-        log.info("获取资源库统计数据");
-        Map<String, Object> stats = new HashMap<>();
-
-        Long libraryCount = libraryMapper.selectCount(null);
-        Long itemCount = itemMapper.selectCount(null);
-
-        stats.put("totalLibraries", libraryCount);
-        stats.put("totalItems", itemCount);
-
-        // 按资源库类型统计资源数量（绘本资源、教学材料等）
-        Map<String, Long> itemsByLibraryType = new HashMap<>();
-        LambdaQueryWrapper<ResourceLibrary> libWrapper = new LambdaQueryWrapper<>();
-        for (ResourceLibrary lib : libraryMapper.selectList(libWrapper)) {
-            String type = lib.getLibraryType();
-            if (type != null) {
-                LambdaQueryWrapper<ResourceItem> itemWrapper = new LambdaQueryWrapper<>();
-                itemWrapper.eq(ResourceItem::getLibraryId, String.valueOf(lib.getId()));
-                long count = itemMapper.selectCount(itemWrapper);
-                itemsByLibraryType.merge(type, count, Long::sum);
-            }
-        }
-        stats.put("itemsByLibraryType", itemsByLibraryType);
-
-        log.info("资源库统计数据：totalLibraries={}, totalItems={}, itemsByLibraryType={}", libraryCount, itemCount, itemsByLibraryType);
-        return stats;
-    }
-
+    Map<String, Object> getStats();
 }
diff --git a/reading-platform-java/src/main/java/com/reading/platform/service/ThemeService.java b/reading-platform-java/src/main/java/com/reading/platform/service/ThemeService.java
index ade540a..9a4ef77 100644
--- a/reading-platform-java/src/main/java/com/reading/platform/service/ThemeService.java
+++ b/reading-platform-java/src/main/java/com/reading/platform/service/ThemeService.java
@@ -1,142 +1,42 @@
 package com.reading.platform.service;
 
-import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
-import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
-import com.reading.platform.common.exception.BusinessException;
-import com.reading.platform.entity.CoursePackage;
+import com.baomidou.mybatisplus.extension.service.IService;
 import com.reading.platform.entity.Theme;
-import com.reading.platform.mapper.CoursePackageMapper;
-import com.reading.platform.mapper.ThemeMapper;
-import lombok.RequiredArgsConstructor;
-import lombok.extern.slf4j.Slf4j;
-import org.springframework.stereotype.Service;
-import org.springframework.transaction.annotation.Transactional;
 
 import java.util.List;
 
 /**
- * 主题字典服务
+ * 主题字典服务接口
  */
-@Slf4j
-@Service
-@RequiredArgsConstructor
-public class ThemeService extends ServiceImpl<ThemeMapper, Theme> {
-
-    private final ThemeMapper themeMapper;
-    private final CoursePackageMapper courseMapper;
+public interface ThemeService extends IService<Theme> {
 
     /**
      * 查询所有主题
      */
-    public List<Theme> findAll() {
-        log.info("查询所有主题");
-        List<Theme> result = lambdaQuery()
-                .orderByAsc(Theme::getSortOrder)
-                .list();
-        log.info("查询所有主题成功，count={}", result.size());
-        return result;
-    }
+    List<Theme> findAll();
 
     /**
      * 查询主题详情
      */
-    public Theme findById(Long id) {
-        log.info("查询主题详情，id={}", id);
-        Theme theme = themeMapper.selectById(id);
-        if (theme == null) {
-            log.warn("主题不存在，id={}", id);
-            throw new BusinessException("主题不存在");
-        }
-        return theme;
-    }
+    Theme findById(Long id);
 
     /**
      * 创建主题
      */
-    @Transactional(rollbackFor = Exception.class)
-    public Theme create(String name, String description, Integer sortOrder) {
-        log.info("创建主题，name={}, sortOrder={}", name, sortOrder);
-        // 获取最大排序号
-        Integer maxSortOrder = themeMapper.selectList(null)
-                .stream()
-                .map(Theme::getSortOrder)
-                .max(Integer::compareTo)
-                .orElse(0);
-
-        Theme theme = new Theme();
-        theme.setName(name);
-        theme.setDescription(description);
-        theme.setSortOrder(sortOrder != null ? sortOrder : maxSortOrder + 1);
-        theme.setStatus("ACTIVE");
-        themeMapper.insert(theme);
-
-        log.info("主题创建成功，id={}", theme.getId());
-        return theme;
-    }
+    Theme create(String name, String description, Integer sortOrder);
 
     /**
      * 更新主题
      */
-    @Transactional(rollbackFor = Exception.class)
-    public Theme update(Long id, String name, String description, Integer sortOrder, String status) {
-        log.info("更新主题，id={}, name={}, status={}", id, name, status);
-        Theme theme = themeMapper.selectById(id);
-        if (theme == null) {
-            log.warn("主题不存在，id={}", id);
-            throw new BusinessException("主题不存在");
-        }
-
-        if (name != null) {
-            theme.setName(name);
-        }
-        if (description != null) {
-            theme.setDescription(description);
-        }
-        if (sortOrder != null) {
-            theme.setSortOrder(sortOrder);
-        }
-        if (status != null) {
-            theme.setStatus(status);
-        }
-
-        themeMapper.updateById(theme);
-        log.info("主题更新成功，id={}", id);
-        return theme;
-    }
+    Theme update(Long id, String name, String description, Integer sortOrder, String status);
 
     /**
      * 删除主题
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void delete(Long id) {
-        log.info("删除主题，id={}", id);
-        // 检查是否有关联课程
-        Long courseCount = courseMapper.selectCount(
-                new LambdaQueryWrapper<CoursePackage>().eq(CoursePackage::getThemeId, id)
-        );
-
-        if (courseCount > 0) {
-            log.warn("删除主题失败，该主题下有 {} 个课程包，id={}", courseCount, id);
-            throw new BusinessException("该主题下有 " + courseCount + " 个课程包，无法删除");
-        }
-
-        themeMapper.deleteById(id);
-        log.info("主题删除成功，id={}", id);
-    }
+    void delete(Long id);
 
     /**
      * 重新排序
      */
-    @Transactional(rollbackFor = Exception.class)
-    public void reorder(List<Long> ids) {
-        log.info("重新排序主题，count={}", ids.size());
-        for (int i = 0; i < ids.size(); i++) {
-            Theme theme = themeMapper.selectById(ids.get(i));
-            if (theme != null) {
-                theme.setSortOrder(i + 1);
-                themeMapper.updateById(theme);
-            }
-        }
-        log.info("主题重新排序成功");
-    }
+    void reorder(List<Long> ids);
 }
diff --git a/reading-platform-java/src/main/java/com/reading/platform/service/impl/CourseCollectionServiceImpl.java b/reading-platform-java/src/main/java/com/reading/platform/service/impl/CourseCollectionServiceImpl.java
new file mode 100644
index 0000000..f84cd07
--- /dev/null
+++ b/reading-platform-java/src/main/java/com/reading/platform/service/impl/CourseCollectionServiceImpl.java
@@ -0,0 +1,633 @@
+package com.reading.platform.service.impl;
+
+import com.alibaba.fastjson2.JSON;
+import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
+import com.reading.platform.common.enums.CourseStatus;
+import com.reading.platform.common.enums.TenantPackageStatus;
+import com.reading.platform.common.exception.BusinessException;
+import com.reading.platform.common.response.PageResult;
+import com.reading.platform.dto.response.CourseCollectionResponse;
+import com.reading.platform.dto.response.CoursePackageResponse;
+import com.reading.platform.entity.*;
+import com.reading.platform.mapper.*;
+import com.reading.platform.service.CourseCollectionService;
+import com.reading.platform.service.CourseLessonService;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+import org.springframework.util.StringUtils;
+
+import java.time.LocalDateTime;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Collectors;
+
+/**
+ * 课程套餐服务实现类（两层结构 - 最上层）
+ */
+@Slf4j
+@Service
+@RequiredArgsConstructor
+public class CourseCollectionServiceImpl extends ServiceImpl<CourseCollectionMapper, CourseCollection> implements CourseCollectionService {
+
+    private final CourseCollectionMapper collectionMapper;
+    private final CourseCollectionPackageMapper collectionPackageMapper;
+    private final CoursePackageMapper packageMapper;
+    private final TenantPackageMapper tenantPackageMapper;
+    private final CoursePackageCourseMapper packageCoursePackageMapper;
+    private final CoursePackageMapper courseMapper;
+    private final CourseLessonService courseLessonService;
+
+    /**
+     * 查询租户的课程套餐列表
+     */
+    @Override
+    public List<CourseCollectionResponse> findTenantCollections(Long tenantId) {
+        log.info("查询租户课程套餐，tenantId={}", tenantId);
+
+        // 查询租户的课程套餐关联
+        List<TenantPackage> tenantPackages = tenantPackageMapper.selectList(
+                new LambdaQueryWrapper<TenantPackage>()
+                        .eq(TenantPackage::getTenantId, tenantId)
+                        .eq(TenantPackage::getStatus, TenantPackageStatus.ACTIVE.getCode())
+                        .isNotNull(TenantPackage::getCollectionId)
+                        .orderByDesc(TenantPackage::getCreatedAt)
+        );
+
+        log.info("查询到{}条租户套餐关联记录", tenantPackages.size());
+        for (TenantPackage tp : tenantPackages) {
+            log.info("  - collection_id: {}, start_date: {}, end_date: {}",
+                tp.getCollectionId(), tp.getStartDate(), tp.getEndDate());
+        }
+
+        // 获取套餐详情并转换为响应对象
+        List<CourseCollectionResponse> result = tenantPackages.stream()
+                .map(tp -> {
+                    CourseCollection collection = collectionMapper.selectById(tp.getCollectionId());
+                    if (collection == null) {
+                        log.warn("套餐不存在，collection_id={}", tp.getCollectionId());
+                        return null;
+                    }
+                    // 过滤下架状态的课程套餐
+                    if (CourseStatus.ARCHIVED.getCode().equals(collection.getStatus())) {
+                        log.warn("套餐已下架，collection_id={}", tp.getCollectionId());
+                        return null;
+                    }
+                    log.info("返回套餐：id={}, name={}, package_count={}",
+                        collection.getId(), collection.getName(), collection.getPackageCount());
+                    CourseCollectionResponse response = toResponse(collection);
+                    // 设置租户套餐的额外信息（如果有）
+                    response.setStartDate(tp.getStartDate());
+                    response.setEndDate(tp.getEndDate());
+                    return response;
+                })
+                .filter(r -> r != null)
+                .collect(Collectors.toList());
+
+        log.info("查询到{}个课程套餐", result.size());
+        return result;
+    }
+
+    /**
+     * 获取课程套餐详情（包含课程包列表）
+     */
+    @Override
+    public CourseCollectionResponse getCollectionDetail(Long collectionId) {
+        log.info("获取课程套餐详情，collectionId={}", collectionId);
+
+        CourseCollection collection = collectionMapper.selectById(collectionId);
+        if (collection == null) {
+            log.warn("课程套餐不存在，collectionId={}", collectionId);
+            return null;
+        }
+
+        return toResponse(collection);
+    }
+
+    /**
+     * 分页查询课程套餐
+     */
+    @Override
+    public Page<CourseCollectionResponse> pageCollections(Integer pageNum, Integer pageSize, String status) {
+        log.info("分页查询课程套餐，pageNum={}, pageSize={}, status={}", pageNum, pageSize, status);
+
+        LambdaQueryWrapper<CourseCollection> wrapper = new LambdaQueryWrapper<>();
+        if (StringUtils.hasText(status)) {
+            wrapper.eq(CourseCollection::getStatus, status);
+        }
+        wrapper.orderByDesc(CourseCollection::getCreatedAt);
+
+        Page<CourseCollection> page = collectionMapper.selectPage(
+                new Page<>(pageNum, pageSize),
+                wrapper
+        );
+
+        // 转换为响应对象
+        List<CourseCollectionResponse> responses = page.getRecords().stream()
+                .map(this::toResponse)
+                .collect(Collectors.toList());
+
+        Page<CourseCollectionResponse> result = new Page<>(page.getCurrent(), page.getSize(), page.getTotal());
+        result.setRecords(responses);
+        return result;
+    }
+
+    /**
+     * 获取课程套餐下的课程包列表
+     */
+    @Override
+    public List<CoursePackageResponse> getPackagesByCollection(Long collectionId) {
+        log.info("获取课程套餐的课程包列表，collectionId={}", collectionId);
+
+        // 查询关联关系
+        List<CourseCollectionPackage> associations = collectionPackageMapper.selectList(
+                new LambdaQueryWrapper<CourseCollectionPackage>()
+                        .eq(CourseCollectionPackage::getCollectionId, collectionId)
+                        .orderByAsc(CourseCollectionPackage::getSortOrder)
+        );
+
+        if (associations.isEmpty()) {
+            return new ArrayList<>();
+        }
+
+        // 获取课程包详情
+        List<Long> packageIds = associations.stream()
+                .map(CourseCollectionPackage::getPackageId)
+                .collect(Collectors.toList());
+
+        List<CoursePackage> packages = packageMapper.selectList(
+                new LambdaQueryWrapper<CoursePackage>()
+                        .in(CoursePackage::getId, packageIds)
+                        .eq(CoursePackage::getStatus, CourseStatus.PUBLISHED.getCode())
+        );
+
+        // 转换为响应对象并设置排序号
+        List<CoursePackageResponse> result = packages.stream()
+                .map(pkg -> {
+                    CoursePackageResponse response = toPackageResponse(pkg);
+                    // 设置排序号
+                    associations.stream()
+                            .filter(a -> a.getPackageId().equals(pkg.getId()))
+                            .findFirst()
+                            .ifPresent(a -> response.setSortOrder(a.getSortOrder()));
+                    return response;
+                })
+                .collect(Collectors.toList());
+
+        log.info("查询到{}个课程包", result.size());
+        return result;
+    }
+
+    /**
+     * 创建课程套餐
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public CourseCollectionResponse createCollection(String name, String description, Long price,
+                                              Long discountPrice, String discountType, String[] gradeLevels) {
+        log.info("创建课程套餐，name={}", name);
+
+        CourseCollection collection = new CourseCollection();
+        collection.setName(name);
+        collection.setDescription(description);
+        collection.setPrice(price);
+        collection.setDiscountPrice(discountPrice);
+        collection.setDiscountType(discountType);
+        // 将数组转为 JSON 字符串存储到 JSON 字段
+        collection.setGradeLevels(JSON.toJSONString(gradeLevels));
+        collection.setPackageCount(0);
+        collection.setStatus(CourseStatus.DRAFT.getCode());
+
+        collectionMapper.insert(collection);
+
+        log.info("课程套餐创建成功，id={}", collection.getId());
+        return toResponse(collection);
+    }
+
+    /**
+     * 设置课程套餐的课程包
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void setCollectionPackages(Long collectionId, List<Long> packageIds) {
+        log.info("设置课程套餐的课程包，collectionId={}, packageCount={}", collectionId, packageIds.size());
+
+        // 验证课程套餐是否存在
+        CourseCollection collection = collectionMapper.selectById(collectionId);
+        if (collection == null) {
+            throw new BusinessException("课程套餐不存在");
+        }
+
+        // 去重：保持首次出现顺序，避免 uk_collection_package 唯一约束冲突
+        List<Long> distinctIds = packageIds.stream().distinct().collect(Collectors.toList());
+
+        // 验证课程包是否存在（应用层外键约束）
+        if (!distinctIds.isEmpty()) {
+            List<CoursePackage> packages = packageMapper.selectList(
+                    new LambdaQueryWrapper<CoursePackage>()
+                            .in(CoursePackage::getId, distinctIds)
+            );
+            if (packages.size() != distinctIds.size()) {
+                throw new BusinessException("存在无效的课程包 ID");
+            }
+        }
+
+        // 删除旧的关联
+        collectionPackageMapper.delete(
+                new LambdaQueryWrapper<CourseCollectionPackage>()
+                        .eq(CourseCollectionPackage::getCollectionId, collectionId)
+        );
+
+        // 创建新的关联（在事务内顺序插入）
+        for (int i = 0; i < distinctIds.size(); i++) {
+            CourseCollectionPackage association = new CourseCollectionPackage();
+            association.setCollectionId(collectionId);
+            association.setPackageId(distinctIds.get(i));
+            association.setSortOrder(i + 1);
+            collectionPackageMapper.insert(association);
+        }
+
+        // 更新课程包数量（复用前面已验证的 collection 变量）
+        collection.setPackageCount(distinctIds.size());
+        collectionMapper.updateById(collection);
+
+        log.info("课程套餐的课程包设置完成");
+    }
+
+    /**
+     * 更新课程套餐
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public CourseCollectionResponse updateCollection(Long id, String name, String description, Long price,
+                                              Long discountPrice, String discountType, String[] gradeLevels) {
+        log.info("更新课程套餐，id={}", id);
+
+        CourseCollection collection = collectionMapper.selectById(id);
+        if (collection == null) {
+            throw new IllegalArgumentException("课程套餐不存在");
+        }
+
+        collection.setName(name);
+        collection.setDescription(description);
+        collection.setPrice(price);
+        collection.setDiscountPrice(discountPrice);
+        collection.setDiscountType(discountType);
+        // 将数组转为 JSON 字符串存储到 JSON 字段
+        collection.setGradeLevels(JSON.toJSONString(gradeLevels));
+
+        collectionMapper.updateById(collection);
+
+        log.info("课程套餐更新成功，id={}", id);
+        return toResponse(collection);
+    }
+
+    /**
+     * 删除课程套餐
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void deleteCollection(Long id) {
+        log.info("删除课程套餐，id={}", id);
+
+        // 检查是否有租户正在使用此课程套餐
+        Long tenantCount = tenantPackageMapper.selectCount(
+                new LambdaQueryWrapper<TenantPackage>()
+                        .eq(TenantPackage::getCollectionId, id)
+                        .eq(TenantPackage::getStatus, TenantPackageStatus.ACTIVE)
+        );
+
+        if (tenantCount > 0) {
+            log.warn("删除课程套餐失败，有 {} 个租户正在使用此套餐，id={}", tenantCount, id);
+            throw new BusinessException("有 " + tenantCount + " 个租户正在使用此课程套餐，无法删除");
+        }
+
+        // 清理所有状态的租户套餐关联记录（包括非活跃状态）
+        List<TenantPackage> allTenantPackages = tenantPackageMapper.selectList(
+                new LambdaQueryWrapper<TenantPackage>()
+                        .eq(TenantPackage::getCollectionId, id)
+        );
+
+        if (!allTenantPackages.isEmpty()) {
+            tenantPackageMapper.delete(
+                    new LambdaQueryWrapper<TenantPackage>()
+                            .eq(TenantPackage::getCollectionId, id)
+            );
+            log.info("已清理 {} 条租户套餐关联记录", allTenantPackages.size());
+        }
+
+        // 删除课程套餐与课程包的关联关系
+        List<CourseCollectionPackage> collectionPackages = collectionPackageMapper.selectList(
+                new LambdaQueryWrapper<CourseCollectionPackage>()
+                        .eq(CourseCollectionPackage::getCollectionId, id)
+        );
+
+        if (!collectionPackages.isEmpty()) {
+            collectionPackageMapper.delete(
+                    new LambdaQueryWrapper<CourseCollectionPackage>()
+                            .eq(CourseCollectionPackage::getCollectionId, id)
+            );
+            log.info("已清理 {} 条课程包关联记录", collectionPackages.size());
+        }
+
+        // 删除课程套餐
+        collectionMapper.deleteById(id);
+
+        log.info("课程套餐删除成功，id={}", id);
+    }
+
+    /**
+     * 发布课程套餐
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void publishCollection(Long id) {
+        log.info("发布课程套餐，id={}", id);
+
+        CourseCollection collection = collectionMapper.selectById(id);
+        if (collection == null) {
+            throw new IllegalArgumentException("课程套餐不存在");
+        }
+
+        collection.setStatus(CourseStatus.PUBLISHED.getCode());
+        collection.setPublishedAt(LocalDateTime.now());
+        collectionMapper.updateById(collection);
+
+        log.info("课程套餐发布成功，id={}", id);
+    }
+
+    /**
+     * 下架课程套餐
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void archiveCollection(Long id) {
+        log.info("下架课程套餐，id={}", id);
+
+        CourseCollection collection = collectionMapper.selectById(id);
+        if (collection == null) {
+            throw new IllegalArgumentException("课程套餐不存在");
+        }
+
+        collection.setStatus(CourseStatus.ARCHIVED.getCode());
+        collectionMapper.updateById(collection);
+
+        log.info("课程套餐下架成功，id={}", id);
+    }
+
+    /**
+     * 重新发布课程套餐
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void republishCollection(Long id) {
+        log.info("重新发布课程套餐，id={}", id);
+
+        CourseCollection collection = collectionMapper.selectById(id);
+        if (collection == null) {
+            throw new IllegalArgumentException("课程套餐不存在");
+        }
+
+        collection.setStatus(CourseStatus.PUBLISHED.getCode());
+        collection.setPublishedAt(LocalDateTime.now());
+        collectionMapper.updateById(collection);
+
+        log.info("课程套餐重新发布成功，id={}", id);
+    }
+
+    /**
+     * 撤销审核
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void withdrawCollection(Long id) {
+        log.info("撤销课程套餐审核，id={}", id);
+
+        CourseCollection collection = collectionMapper.selectById(id);
+        if (collection == null) {
+            throw new IllegalArgumentException("课程套餐不存在");
+        }
+
+        collection.setStatus(CourseStatus.DRAFT.getCode());
+        collectionMapper.updateById(collection);
+
+        log.info("课程套餐审核撤销成功，id={}", id);
+    }
+
+    /**
+     * 提交课程套餐审核
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void submitCollection(Long id) {
+        log.info("提交课程套餐审核，id={}", id);
+
+        CourseCollection collection = collectionMapper.selectById(id);
+        if (collection == null) {
+            throw new IllegalArgumentException("课程套餐不存在");
+        }
+
+        // 检查是否包含课程包
+        if (collection.getPackageCount() == null || collection.getPackageCount() == 0) {
+            throw new BusinessException("课程套餐必须包含至少一个课程包");
+        }
+
+        collection.setStatus(CourseStatus.PENDING.getCode());
+        collection.setSubmittedAt(LocalDateTime.now());
+        collectionMapper.updateById(collection);
+
+        log.info("课程套餐提交审核成功，id={}", id);
+    }
+
+    /**
+     * 审核驳回课程套餐
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void rejectCollection(Long id, String comment) {
+        log.info("审核驳回课程套餐，id={}, comment={}", id, comment);
+
+        CourseCollection collection = collectionMapper.selectById(id);
+        if (collection == null) {
+            throw new IllegalArgumentException("课程套餐不存在");
+        }
+
+        collection.setStatus(CourseStatus.REJECTED.getCode());
+        collection.setReviewedAt(LocalDateTime.now());
+        collection.setReviewComment(comment);
+        collectionMapper.updateById(collection);
+
+        log.info("课程套餐审核驳回成功，id={}", id);
+    }
+
+    /**
+     * 续费租户课程套餐
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void renewTenantCollection(Long tenantId, Long collectionId, java.time.LocalDate endDate, Long pricePaid) {
+        log.info("续费租户课程套餐，tenantId={}, collectionId={}, endDate={}, pricePaid={}", tenantId, collectionId, endDate, pricePaid);
+
+        // 查询现有租户套餐关联
+        List<TenantPackage> existingPackages = tenantPackageMapper.selectList(
+                new LambdaQueryWrapper<TenantPackage>()
+                        .eq(TenantPackage::getTenantId, tenantId)
+                        .eq(TenantPackage::getCollectionId, collectionId)
+        );
+
+        if (!existingPackages.isEmpty()) {
+            // 更新现有记录
+            TenantPackage existing = existingPackages.get(0);
+            existing.setEndDate(endDate);
+            existing.setStatus(TenantPackageStatus.ACTIVE);
+            if (pricePaid != null) {
+                existing.setPricePaid(pricePaid);
+            }
+            existing.setUpdatedAt(LocalDateTime.now());
+            tenantPackageMapper.updateById(existing);
+            log.info("租户课程套餐续费成功，tenantId={}, collectionId={}", tenantId, collectionId);
+        } else {
+            // 查询课程套餐信息
+            CourseCollection collection = collectionMapper.selectById(collectionId);
+            if (collection == null) {
+                throw new IllegalArgumentException("课程套餐不存在");
+            }
+
+            // 创建新记录
+            TenantPackage tp = new TenantPackage();
+            tp.setTenantId(tenantId);
+            tp.setCollectionId(collectionId);
+            tp.setStartDate(java.time.LocalDate.now());
+            tp.setEndDate(endDate);
+            tp.setStatus(TenantPackageStatus.ACTIVE);
+            tp.setPricePaid(pricePaid != null ? pricePaid :
+                (collection.getDiscountPrice() != null ? collection.getDiscountPrice() : collection.getPrice()));
+            tp.setCreatedAt(LocalDateTime.now());
+            tenantPackageMapper.insert(tp);
+            log.info("租户课程套餐新办成功，tenantId={}, collectionId={}", tenantId, collectionId);
+        }
+    }
+
+    /**
+     * 解析适用年级：数据库存储为 JSON 数组 ["小班","中班","大班"]，需正确解析
+     */
+    private String[] parseGradeLevels(String gradeLevels) {
+        if (!StringUtils.hasText(gradeLevels)) {
+            return new String[0];
+        }
+        try {
+            if (gradeLevels.trim().startsWith("[")) {
+                return JSON.parseArray(gradeLevels, String.class).toArray(new String[0]);
+            }
+            // 兼容旧数据：逗号分隔格式
+            return gradeLevels.split(",");
+        } catch (Exception e) {
+            log.warn("解析 gradeLevels 失败：{}", gradeLevels, e);
+            return new String[0];
+        }
+    }
+
+    /**
+     * 转换为响应对象
+     */
+    private CourseCollectionResponse toResponse(CourseCollection collection) {
+        // 获取课程包列表
+        List<CourseCollectionResponse.CoursePackageItem> packages = getPackagesByCollection(collection.getId()).stream()
+                .map(pkg -> {
+                    CourseCollectionResponse.CoursePackageItem item = new CourseCollectionResponse.CoursePackageItem();
+                    item.setId(pkg.getId());
+                    item.setName(pkg.getName());
+                    item.setDescription(pkg.getDescription());
+                    item.setGradeLevels(pkg.getGradeLevels() != null ? pkg.getGradeLevels() : new String[0]);
+                    item.setCourseCount(pkg.getCourseCount() != null ? pkg.getCourseCount() : 0);
+                    item.setSortOrder(pkg.getSortOrder());
+                    return item;
+                })
+                .collect(Collectors.toList());
+
+        return CourseCollectionResponse.builder()
+                .id(collection.getId())
+                .name(collection.getName())
+                .description(collection.getDescription())
+                .price(collection.getPrice())
+                .discountPrice(collection.getDiscountPrice())
+                .discountType(collection.getDiscountType())
+                .gradeLevels(parseGradeLevels(collection.getGradeLevels()))
+                .packageCount(collection.getPackageCount())
+                .status(collection.getStatus())
+                .submittedAt(collection.getSubmittedAt())
+                .submittedBy(collection.getSubmittedBy())
+                .reviewedAt(collection.getReviewedAt())
+                .reviewedBy(collection.getReviewedBy())
+                .reviewComment(collection.getReviewComment())
+                .publishedAt(collection.getPublishedAt())
+                .createdAt(collection.getCreatedAt())
+                .updatedAt(collection.getUpdatedAt())
+                .packages(packages)
+                .build();
+    }
+
+    /**
+     * 转换为课程包响应对象（包含课程列表和排课计划参考）
+     */
+    private CoursePackageResponse toPackageResponse(CoursePackage pkg) {
+        // 解析 gradeTags（CoursePackage 使用 gradeTags）
+        String[] gradeLevelsArray = new String[0];
+        if (pkg.getGradeTags() != null && !pkg.getGradeTags().isEmpty()) {
+            try {
+                // gradeTags 是 JSON 数组格式，尝试解析
+                if (pkg.getGradeTags().startsWith("[")) {
+                    gradeLevelsArray = com.alibaba.fastjson2.JSON.parseArray(pkg.getGradeTags(), String.class).toArray(new String[0]);
+                } else {
+                    gradeLevelsArray = pkg.getGradeTags().split(",");
+                }
+            } catch (Exception e) {
+                gradeLevelsArray = new String[0];
+            }
+        }
+
+        List<CoursePackageResponse.CoursePackageCourseItem> courseItems = new ArrayList<>();
+
+        // 查询课程包关联的课程环节
+        List<CourseLesson> lessons = courseLessonService.findByCourseId(pkg.getId());
+
+        if (!lessons.isEmpty()) {
+            courseItems = lessons.stream()
+                    .map(lesson -> {
+                        CoursePackageResponse.CoursePackageCourseItem item = new CoursePackageResponse.CoursePackageCourseItem();
+                        item.setId(lesson.getId());
+                        item.setName(lesson.getName());
+                        item.setGradeLevel(null); // 课程环节没有年级字段
+                        item.setSortOrder(lesson.getSortOrder());
+                        item.setScheduleRefData(pkg.getScheduleRefData());
+                        item.setLessonType(lesson.getLessonType());
+                        return item;
+                    })
+                    .collect(Collectors.toList());
+        }
+
+        return CoursePackageResponse.builder()
+                .id(pkg.getId())
+                .name(pkg.getName())
+                .description(pkg.getDescription())
+                .price(null) // CoursePackage 没有价格字段
+                .discountPrice(null)
+                .discountType(null)
+                .gradeLevels(gradeLevelsArray)
+                .courseCount(lessons.size()) // 使用课程环节数量
+                .status(pkg.getStatus())
+                .submittedAt(pkg.getSubmittedAt())
+                .submittedBy(pkg.getSubmittedBy())
+                .reviewedAt(pkg.getReviewedAt())
+                .reviewedBy(pkg.getReviewedBy())
+                .reviewComment(pkg.getReviewComment())
+                .publishedAt(pkg.getPublishedAt())
+                .createdAt(pkg.getCreatedAt())
+                .updatedAt(pkg.getUpdatedAt())
+                .courses(courseItems)
+                .build();
+    }
+}
diff --git a/reading-platform-java/src/main/java/com/reading/platform/service/impl/CourseLessonServiceImpl.java b/reading-platform-java/src/main/java/com/reading/platform/service/impl/CourseLessonServiceImpl.java
new file mode 100644
index 0000000..26d07b3
--- /dev/null
+++ b/reading-platform-java/src/main/java/com/reading/platform/service/impl/CourseLessonServiceImpl.java
@@ -0,0 +1,430 @@
+package com.reading.platform.service.impl;
+
+import com.alibaba.fastjson2.JSON;
+import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
+import com.reading.platform.common.enums.TenantPackageStatus;
+import com.reading.platform.common.exception.BusinessException;
+import com.reading.platform.entity.*;
+import com.reading.platform.mapper.*;
+import com.reading.platform.service.CourseLessonService;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.time.LocalDateTime;
+import java.util.List;
+
+/**
+ * 课程环节服务实现类
+ */
+@Slf4j
+@Service
+@RequiredArgsConstructor
+public class CourseLessonServiceImpl extends ServiceImpl<CourseLessonMapper, CourseLesson> implements CourseLessonService {
+
+    private final CourseLessonMapper courseLessonMapper;
+    private final LessonStepMapper lessonStepMapper;
+    private final LessonStepResourceMapper lessonStepResourceMapper;
+    private final TenantCourseMapper tenantCourseMapper;
+    private final TenantPackageMapper tenantPackageMapper;
+
+    /**
+     * 查询课程的所有环节
+     */
+    @Override
+    public List<CourseLesson> findByCourseId(Long courseId) {
+        log.info("查询课程的所有环节，courseId={}", courseId);
+        List<CourseLesson> result = courseLessonMapper.selectList(
+                new LambdaQueryWrapper<CourseLesson>()
+                        .eq(CourseLesson::getCourseId, courseId)
+                        .orderByAsc(CourseLesson::getSortOrder)
+        );
+        log.info("查询课程环节成功，courseId={}, count={}", courseId, result.size());
+        return result;
+    }
+
+    /**
+     * 查询课程环节详情
+     */
+    @Override
+    public CourseLesson findById(Long id) {
+        log.info("查询课程环节详情，id={}", id);
+        CourseLesson lesson = courseLessonMapper.selectById(id);
+        if (lesson == null) {
+            log.warn("课程环节不存在，id={}", id);
+            throw new BusinessException("课程环节不存在");
+        }
+        return lesson;
+    }
+
+    /**
+     * 按类型查询课程环节
+     */
+    @Override
+    public CourseLesson findByType(Long courseId, String lessonType) {
+        log.info("按类型查询课程环节，courseId={}, lessonType={}", courseId, lessonType);
+        CourseLesson result = courseLessonMapper.selectOne(
+                new LambdaQueryWrapper<CourseLesson>()
+                        .eq(CourseLesson::getCourseId, courseId)
+                        .eq(CourseLesson::getLessonType, lessonType)
+        );
+        if (result != null) {
+            log.info("查询课程环节成功，courseId={}, lessonType={}, id={}", courseId, lessonType, result.getId());
+        }
+        return result;
+    }
+
+    /**
+     * 创建课程环节
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public CourseLesson create(Long courseId, String lessonType, String name, String description,
+                               Integer duration, String videoPath, String videoName,
+                               String pptPath, String pptName, String pdfPath, String pdfName,
+                               String objectives, String preparation, String extension,
+                               String reflection, String assessmentData, Boolean useTemplate) {
+        log.info("创建课程环节，courseId={}, lessonType={}, name={}", courseId, lessonType, name);
+        // 检查是否已存在相同类型的课程
+        CourseLesson existing = findByType(courseId, lessonType);
+        if (existing != null) {
+            log.warn("创建课程环节失败，已存在相同类型的课程环节，courseId={}, lessonType={}", courseId, lessonType);
+            throw new BusinessException("该课程包已存在 " + lessonType + " 类型的课程");
+        }
+
+        // 获取最大排序号
+        Integer maxSortOrder = courseLessonMapper.selectList(
+                        new LambdaQueryWrapper<CourseLesson>()
+                                .eq(CourseLesson::getCourseId, courseId)
+                ).stream()
+                .map(CourseLesson::getSortOrder)
+                .max(Integer::compareTo)
+                .orElse(0);
+
+        CourseLesson lesson = new CourseLesson();
+        lesson.setCourseId(courseId);
+        lesson.setLessonType(lessonType);
+        lesson.setName(name);
+        lesson.setDescription(description);
+        lesson.setDuration(duration);
+        lesson.setVideoPath(videoPath);
+        lesson.setVideoName(videoName);
+        lesson.setPptPath(pptPath);
+        lesson.setPptName(pptName);
+        lesson.setPdfPath(pdfPath);
+        lesson.setPdfName(pdfName);
+        lesson.setObjectives(objectives);
+        lesson.setPreparation(preparation);
+        lesson.setExtension(extension);
+        lesson.setReflection(reflection);
+        // 确保 assessment_data 为有效 JSON，MySQL JSON 列不接受纯文本
+        lesson.setAssessmentData(toValidJsonOrNull(assessmentData));
+        lesson.setUseTemplate(useTemplate);
+        lesson.setSortOrder(maxSortOrder + 1);
+        lesson.setCreatedAt(LocalDateTime.now());
+
+        courseLessonMapper.insert(lesson);
+        log.info("课程环节创建成功，id={}, courseId={}, lessonType={}", lesson.getId(), courseId, lessonType);
+        return lesson;
+    }
+
+    /**
+     * 更新课程环节
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public CourseLesson update(Long id, String name, String description, Integer duration,
+                               String videoPath, String videoName, String pptPath, String pptName,
+                               String pdfPath, String pdfName, String objectives, String preparation,
+                               String extension, String reflection, String assessmentData, Boolean useTemplate) {
+        log.info("更新课程环节，id={}", id);
+        CourseLesson lesson = courseLessonMapper.selectById(id);
+        if (lesson == null) {
+            log.warn("课程环节不存在，id={}", id);
+            throw new BusinessException("课程不存在");
+        }
+
+        if (name != null) {
+            lesson.setName(name);
+        }
+        if (description != null) {
+            lesson.setDescription(description);
+        }
+        if (duration != null) {
+            lesson.setDuration(duration);
+        }
+        if (videoPath != null) {
+            lesson.setVideoPath(videoPath);
+        }
+        if (videoName != null) {
+            lesson.setVideoName(videoName);
+        }
+        if (pptPath != null) {
+            lesson.setPptPath(pptPath);
+        }
+        if (pptName != null) {
+            lesson.setPptName(pptName);
+        }
+        if (pdfPath != null) {
+            lesson.setPdfPath(pdfPath);
+        }
+        if (pdfName != null) {
+            lesson.setPdfName(pdfName);
+        }
+        if (objectives != null) {
+            lesson.setObjectives(objectives);
+        }
+        if (preparation != null) {
+            lesson.setPreparation(preparation);
+        }
+        if (extension != null) {
+            lesson.setExtension(extension);
+        }
+        if (reflection != null) {
+            lesson.setReflection(reflection);
+        }
+        if (assessmentData != null) {
+            lesson.setAssessmentData(toValidJsonOrNull(assessmentData));
+        }
+        if (useTemplate != null) {
+            lesson.setUseTemplate(useTemplate);
+        }
+
+        lesson.setUpdatedAt(LocalDateTime.now());
+        courseLessonMapper.updateById(lesson);
+        log.info("课程环节更新成功，id={}", id);
+        return lesson;
+    }
+
+    /**
+     * 删除课程环节
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void delete(Long id) {
+        log.info("删除课程环节，id={}", id);
+        CourseLesson lesson = courseLessonMapper.selectById(id);
+        if (lesson == null) {
+            log.warn("课程环节不存在，id={}", id);
+            throw new BusinessException("课程不存在");
+        }
+
+        courseLessonMapper.deleteById(id);
+        log.info("课程环节删除成功，id={}", id);
+    }
+
+    /**
+     * 重新排序课程环节
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void reorder(Long courseId, List<Long> lessonIds) {
+        log.info("重新排序课程环节，courseId={}, count={}", courseId, lessonIds.size());
+        for (int i = 0; i < lessonIds.size(); i++) {
+            CourseLesson lesson = courseLessonMapper.selectById(lessonIds.get(i));
+            if (lesson != null && lesson.getCourseId().equals(courseId)) {
+                lesson.setSortOrder(i + 1);
+                courseLessonMapper.updateById(lesson);
+            }
+        }
+        log.info("课程环节重新排序成功，courseId={}", courseId);
+    }
+
+    /**
+     * 查询课程环节的教学环节
+     */
+    @Override
+    public List<LessonStep> findSteps(Long lessonId) {
+        log.info("查询课程环节的教学环节，lessonId={}", lessonId);
+        List<LessonStep> result = lessonStepMapper.selectList(
+                new LambdaQueryWrapper<LessonStep>()
+                        .eq(LessonStep::getLessonId, lessonId)
+                        .orderByAsc(LessonStep::getSortOrder)
+        );
+        log.info("查询教学环节成功，lessonId={}, count={}", lessonId, result.size());
+        return result;
+    }
+
+    /**
+     * 创建教学环节
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public LessonStep createStep(Long lessonId, String name, String content, Integer duration,
+                                 String objective, List<Long> resourceIds) {
+        log.info("创建教学环节，lessonId={}, name={}", lessonId, name);
+        // 获取最大排序号
+        Integer maxSortOrder = lessonStepMapper.selectList(
+                        new LambdaQueryWrapper<LessonStep>()
+                                .eq(LessonStep::getLessonId, lessonId)
+                ).stream()
+                .map(LessonStep::getSortOrder)
+                .max(Integer::compareTo)
+                .orElse(0);
+
+        LessonStep step = new LessonStep();
+        step.setLessonId(lessonId);
+        step.setName(name);
+        step.setContent(content);
+        step.setDuration(duration != null ? duration : 5);
+        step.setObjective(objective);
+        step.setResourceIds(resourceIds != null ? resourceIds.toString() : null);
+        step.setSortOrder(maxSortOrder + 1);
+        step.setCreatedAt(LocalDateTime.now());
+
+        lessonStepMapper.insert(step);
+
+        // 创建环节资源关联
+        if (resourceIds != null && !resourceIds.isEmpty()) {
+            for (int i = 0; i < resourceIds.size(); i++) {
+                LessonStepResource lsr = new LessonStepResource();
+                lsr.setStepId(step.getId());
+                lsr.setResourceId(resourceIds.get(i));
+                lsr.setSortOrder(i);
+                lessonStepResourceMapper.insert(lsr);
+            }
+        }
+
+        log.info("教学环节创建成功，id={}, lessonId={}", step.getId(), lessonId);
+        return step;
+    }
+
+    /**
+     * 更新教学环节
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public LessonStep updateStep(Long stepId, String name, String content, Integer duration,
+                                 String objective, List<Long> resourceIds) {
+        log.info("更新教学环节，stepId={}", stepId);
+        LessonStep step = lessonStepMapper.selectById(stepId);
+        if (step == null) {
+            log.warn("教学环节不存在，stepId={}", stepId);
+            throw new BusinessException("教学环节不存在");
+        }
+
+        if (name != null) {
+            step.setName(name);
+        }
+        if (content != null) {
+            step.setContent(content);
+        }
+        if (duration != null) {
+            step.setDuration(duration);
+        }
+        if (objective != null) {
+            step.setObjective(objective);
+        }
+        if (resourceIds != null) {
+            step.setResourceIds(resourceIds.toString());
+
+            // 删除旧的资源关联
+            lessonStepResourceMapper.delete(
+                    new LambdaQueryWrapper<LessonStepResource>()
+                            .eq(LessonStepResource::getStepId, stepId)
+            );
+
+            // 创建新的资源关联
+            for (int i = 0; i < resourceIds.size(); i++) {
+                LessonStepResource lsr = new LessonStepResource();
+                lsr.setStepId(stepId);
+                lsr.setResourceId(resourceIds.get(i));
+                lsr.setSortOrder(i);
+                lessonStepResourceMapper.insert(lsr);
+            }
+        }
+
+        step.setUpdatedAt(LocalDateTime.now());
+        lessonStepMapper.updateById(step);
+        log.info("教学环节更新成功，stepId={}", stepId);
+        return step;
+    }
+
+    /**
+     * 删除教学环节
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void deleteStep(Long stepId) {
+        log.info("删除教学环节，stepId={}", stepId);
+        lessonStepMapper.deleteById(stepId);
+        log.info("教学环节删除成功，stepId={}", stepId);
+    }
+
+    /**
+     * 重新排序教学环节
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void reorderSteps(Long lessonId, List<Long> stepIds) {
+        log.info("重新排序教学环节，lessonId={}, count={}", lessonId, stepIds.size());
+        for (int i = 0; i < stepIds.size(); i++) {
+            LessonStep step = lessonStepMapper.selectById(stepIds.get(i));
+            if (step != null && step.getLessonId().equals(lessonId)) {
+                step.setSortOrder(i + 1);
+                lessonStepMapper.updateById(step);
+            }
+        }
+        log.info("教学环节重新排序成功，lessonId={}", lessonId);
+    }
+
+    /**
+     * 将 assessmentData 转为 MySQL JSON 列可接受的有效 JSON。
+     * 空值返回 null；已是有效 JSON 则原样返回；否则包装为 JSON 字符串。
+     */
+    private String toValidJsonOrNull(String assessmentData) {
+        if (assessmentData == null || assessmentData.isEmpty()) {
+            return null;
+        }
+        String trimmed = assessmentData.trim();
+        if (trimmed.isEmpty()) {
+            return null;
+        }
+        // 已是有效 JSON（对象或数组）则直接使用
+        if ((trimmed.startsWith("{") && trimmed.endsWith("}")) || (trimmed.startsWith("[") && trimmed.endsWith("]"))) {
+            try {
+                JSON.parse(trimmed);
+                return trimmed;
+            } catch (Exception ignored) {
+                // 解析失败，当作普通文本处理
+            }
+        }
+        // 普通文本包装为 JSON 字符串
+        return JSON.toJSONString(assessmentData);
+    }
+
+    /**
+     * 查询教师的课程环节（带权限检查）
+     */
+    @Override
+    public List<CourseLesson> findCourseLessonsForTeacher(Long courseId, Long tenantId) {
+        log.info("查询教师的课程环节，courseId={}, tenantId={}", courseId, tenantId);
+        // 检查租户是否有权限访问该课程
+        TenantCourse tenantCourse = tenantCourseMapper.selectOne(
+                new LambdaQueryWrapper<TenantCourse>()
+                        .eq(TenantCourse::getTenantId, tenantId)
+                        .eq(TenantCourse::getCourseId, courseId)
+                        .eq(TenantCourse::getEnabled, 1)
+        );
+
+        if (tenantCourse == null) {
+            // 检查是否通过套餐授权
+            Long count = tenantPackageMapper.selectCount(
+                    new LambdaQueryWrapper<TenantPackage>()
+                            .eq(TenantPackage::getTenantId, tenantId)
+                            .eq(TenantPackage::getStatus, TenantPackageStatus.ACTIVE)
+            );
+
+            if (count == 0) {
+                log.warn("无权访问该课程，courseId={}, tenantId={}", courseId, tenantId);
+                throw new BusinessException("无权访问该课程");
+            }
+        }
+
+        List<CourseLesson> result = findByCourseId(courseId);
+        log.info("查询教师的课程环节成功，courseId={}, count={}", courseId, result.size());
+        return result;
+    }
+}
diff --git a/reading-platform-java/src/main/java/com/reading/platform/service/impl/ResourceLibraryServiceImpl.java b/reading-platform-java/src/main/java/com/reading/platform/service/impl/ResourceLibraryServiceImpl.java
new file mode 100644
index 0000000..78f660c
--- /dev/null
+++ b/reading-platform-java/src/main/java/com/reading/platform/service/impl/ResourceLibraryServiceImpl.java
@@ -0,0 +1,286 @@
+package com.reading.platform.service.impl;
+
+import com.alibaba.fastjson2.JSON;
+import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
+import com.reading.platform.common.exception.BusinessException;
+import com.reading.platform.entity.ResourceItem;
+import com.reading.platform.entity.ResourceLibrary;
+import com.reading.platform.mapper.ResourceItemMapper;
+import com.reading.platform.mapper.ResourceLibraryMapper;
+import com.reading.platform.service.ResourceLibraryService;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.stereotype.Service;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * 资源库服务实现类
+ */
+@Slf4j
+@Service
+@RequiredArgsConstructor
+public class ResourceLibraryServiceImpl extends ServiceImpl<ResourceLibraryMapper, ResourceLibrary> implements ResourceLibraryService {
+
+    private final ResourceLibraryMapper libraryMapper;
+    private final ResourceItemMapper itemMapper;
+
+    /**
+     * 分页查询资源库
+     */
+    @Override
+    public Page<ResourceLibrary> findAllLibraries(String libraryType, String keyword, Integer page, Integer pageSize) {
+        log.info("查询资源库列表，libraryType={}, keyword={}, page={}, pageSize={}", libraryType, keyword, page, pageSize);
+        Page<ResourceLibrary> pageParam = new Page<>(page, pageSize);
+        LambdaQueryWrapper<ResourceLibrary> wrapper = new LambdaQueryWrapper<>();
+
+        if (libraryType != null && !libraryType.isEmpty()) {
+            wrapper.eq(ResourceLibrary::getLibraryType, libraryType);
+        }
+
+        if (keyword != null && !keyword.isEmpty()) {
+            wrapper.like(ResourceLibrary::getName, keyword);
+        }
+
+        wrapper.orderByDesc(ResourceLibrary::getCreatedAt);
+
+        Page<ResourceLibrary> result = libraryMapper.selectPage(pageParam, wrapper);
+        log.info("查询资源库列表成功，总数={}", result.getTotal());
+        return result;
+    }
+
+    /**
+     * 查询资源库详情
+     */
+    @Override
+    public ResourceLibrary findLibraryById(String id) {
+        log.info("查询资源库详情，id={}", id);
+        ResourceLibrary library = libraryMapper.selectById(id);
+        if (library == null) {
+            log.warn("资源库不存在，id={}", id);
+            throw new BusinessException("资源库不存在");
+        }
+        return library;
+    }
+
+    /**
+     * 查询资源库（不存在时返回 null）
+     */
+    @Override
+    public ResourceLibrary findLibraryByIdOrNull(String id) {
+        if (id == null || id.isEmpty()) return null;
+        return libraryMapper.selectById(id);
+    }
+
+    /**
+     * 创建资源库
+     */
+    @Override
+    public ResourceLibrary createLibrary(String name, String type, String description, String tenantId) {
+        log.info("创建资源库，name={}, type={}, tenantId={}", name, type, tenantId);
+        ResourceLibrary library = new ResourceLibrary();
+        library.setName(name);
+        library.setLibraryType(type);
+        library.setDescription(description);
+        library.setTenantId(tenantId);
+        library.setStatus("ACTIVE");
+        library.setSortOrder(0);
+
+        libraryMapper.insert(library);
+        log.info("资源库创建成功，id={}", library.getId());
+        return library;
+    }
+
+    /**
+     * 更新资源库
+     */
+    @Override
+    public ResourceLibrary updateLibrary(String id, String name, String description) {
+        log.info("更新资源库，id={}, name={}, description={}", id, name, description);
+        ResourceLibrary library = libraryMapper.selectById(id);
+        if (library == null) {
+            log.warn("资源库不存在，id={}", id);
+            throw new BusinessException("资源库不存在");
+        }
+
+        if (name != null) {
+            library.setName(name);
+        }
+        if (description != null) {
+            library.setDescription(description);
+        }
+
+        libraryMapper.updateById(library);
+        log.info("资源库更新成功，id={}", id);
+        return library;
+    }
+
+    /**
+     * 删除资源库
+     */
+    @Override
+    public void deleteLibrary(String id) {
+        log.info("删除资源库，id={}", id);
+        // 先删除该资源库下的所有资源项
+        LambdaQueryWrapper<ResourceItem> wrapper = new LambdaQueryWrapper<>();
+        wrapper.eq(ResourceItem::getLibraryId, id);
+        itemMapper.delete(wrapper);
+
+        libraryMapper.deleteById(id);
+        log.info("资源库删除成功，id={}", id);
+    }
+
+    /**
+     * 分页查询资源项目
+     */
+    @Override
+    public Page<ResourceItem> findAllItems(String libraryId, String fileType, String keyword, Integer page, Integer pageSize) {
+        log.info("查询资源项目列表，libraryId={}, fileType={}, keyword={}, page={}, pageSize={}", libraryId, fileType, keyword, page, pageSize);
+        Page<ResourceItem> pageParam = new Page<>(page, pageSize);
+        LambdaQueryWrapper<ResourceItem> wrapper = new LambdaQueryWrapper<>();
+
+        if (libraryId != null && !libraryId.isEmpty()) {
+            wrapper.eq(ResourceItem::getLibraryId, libraryId);
+        }
+
+        if (fileType != null && !fileType.isEmpty()) {
+            wrapper.eq(ResourceItem::getFileType, fileType);
+        }
+
+        if (keyword != null && !keyword.isEmpty()) {
+            wrapper.and(w -> w.like(ResourceItem::getTitle, keyword)
+                    .or()
+                    .like(ResourceItem::getDescription, keyword));
+        }
+
+        wrapper.orderByDesc(ResourceItem::getCreatedAt);
+
+        Page<ResourceItem> result = itemMapper.selectPage(pageParam, wrapper);
+        log.info("查询资源项目列表成功，总数={}", result.getTotal());
+        return result;
+    }
+
+    /**
+     * 查询资源项目详情
+     */
+    @Override
+    public ResourceItem findItemById(String id) {
+        log.info("查询资源项目详情，id={}", id);
+        ResourceItem item = itemMapper.selectById(id);
+        if (item == null) {
+            log.warn("资源项目不存在，id={}", id);
+            throw new BusinessException("资源项目不存在");
+        }
+        return item;
+    }
+
+    /**
+     * 创建资源项目（数字资源）
+     */
+    @Override
+    public ResourceItem createItem(String libraryId, String title, String fileType, String filePath,
+                                   Long fileSize, String description, String tags, String tenantId) {
+        log.info("创建资源项目，libraryId={}, title={}, fileType={}, fileSize={}, tenantId={}", libraryId, title, fileType, fileSize, tenantId);
+        ResourceItem item = new ResourceItem();
+        item.setId(null); // 确保由数据库 AUTO_INCREMENT 生成，避免主键冲突
+        item.setLibraryId(libraryId); // 目标资源库 ID
+        item.setTitle(title);
+        item.setName(title); // 数据库 name 字段 NOT NULL，与 title 保持一致
+        item.setDescription(description);
+        item.setFileType(fileType);
+        item.setFilePath(filePath);
+        item.setFileSize(fileSize);
+        item.setTags(tags);
+        item.setSortOrder(0);
+        item.setTenantId(tenantId);
+        item.setStatus("ACTIVE");
+
+        itemMapper.insert(item);
+        log.info("资源项目创建成功，id={}", item.getId());
+        return item;
+    }
+
+    /**
+     * 更新资源项目（数字资源）
+     */
+    @Override
+    public ResourceItem updateItem(String id, String title, String description, String tags) {
+        log.info("更新资源项目，id={}, title={}, description={}, tags={}", id, title, description, tags);
+        ResourceItem item = itemMapper.selectById(id);
+        if (item == null) {
+            log.warn("资源项目不存在，id={}", id);
+            throw new BusinessException("资源项目不存在");
+        }
+
+        if (title != null) {
+            item.setTitle(title);
+        }
+        if (description != null) {
+            item.setDescription(description);
+        }
+        if (tags != null) {
+            item.setTags(tags);
+        }
+
+        itemMapper.updateById(item);
+        log.info("资源项目更新成功，id={}", id);
+        return item;
+    }
+
+    /**
+     * 删除资源项目
+     */
+    @Override
+    public void deleteItem(String id) {
+        log.info("删除资源项目，id={}", id);
+        itemMapper.deleteById(id);
+        log.info("资源项目删除成功，id={}", id);
+    }
+
+    /**
+     * 批量删除资源项目
+     */
+    @Override
+    public void batchDeleteItems(List<String> ids) {
+        log.info("批量删除资源项目，ids={}", ids);
+        itemMapper.deleteBatchIds(ids);
+        log.info("批量删除资源项目成功，数量={}", ids.size());
+    }
+
+    /**
+     * 获取统计数据
+     */
+    @Override
+    public Map<String, Object> getStats() {
+        log.info("获取资源库统计数据");
+        Map<String, Object> stats = new HashMap<>();
+
+        Long libraryCount = libraryMapper.selectCount(null);
+        Long itemCount = itemMapper.selectCount(null);
+
+        stats.put("totalLibraries", libraryCount);
+        stats.put("totalItems", itemCount);
+
+        // 按资源库类型统计资源数量（绘本资源、教学材料等）
+        Map<String, Long> itemsByLibraryType = new HashMap<>();
+        LambdaQueryWrapper<ResourceLibrary> libWrapper = new LambdaQueryWrapper<>();
+        for (ResourceLibrary lib : libraryMapper.selectList(libWrapper)) {
+            String type = lib.getLibraryType();
+            if (type != null) {
+                LambdaQueryWrapper<ResourceItem> itemWrapper = new LambdaQueryWrapper<>();
+                itemWrapper.eq(ResourceItem::getLibraryId, String.valueOf(lib.getId()));
+                long count = itemMapper.selectCount(itemWrapper);
+                itemsByLibraryType.merge(type, count, Long::sum);
+            }
+        }
+        stats.put("itemsByLibraryType", itemsByLibraryType);
+
+        log.info("资源库统计数据：totalLibraries={}, totalItems={}, itemsByLibraryType={}", libraryCount, itemCount, itemsByLibraryType);
+        return stats;
+    }
+
+}
diff --git a/reading-platform-java/src/main/java/com/reading/platform/service/impl/ThemeServiceImpl.java b/reading-platform-java/src/main/java/com/reading/platform/service/impl/ThemeServiceImpl.java
new file mode 100644
index 0000000..3f0f815
--- /dev/null
+++ b/reading-platform-java/src/main/java/com/reading/platform/service/impl/ThemeServiceImpl.java
@@ -0,0 +1,149 @@
+package com.reading.platform.service.impl;
+
+import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
+import com.reading.platform.common.exception.BusinessException;
+import com.reading.platform.entity.CoursePackage;
+import com.reading.platform.entity.Theme;
+import com.reading.platform.mapper.CoursePackageMapper;
+import com.reading.platform.mapper.ThemeMapper;
+import com.reading.platform.service.ThemeService;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.List;
+
+/**
+ * 主题字典服务实现类
+ */
+@Slf4j
+@Service
+@RequiredArgsConstructor
+public class ThemeServiceImpl extends ServiceImpl<ThemeMapper, Theme> implements ThemeService {
+
+    private final ThemeMapper themeMapper;
+    private final CoursePackageMapper courseMapper;
+
+    /**
+     * 查询所有主题
+     */
+    @Override
+    public List<Theme> findAll() {
+        log.info("查询所有主题");
+        List<Theme> result = lambdaQuery()
+                .orderByAsc(Theme::getSortOrder)
+                .list();
+        log.info("查询所有主题成功，count={}", result.size());
+        return result;
+    }
+
+    /**
+     * 查询主题详情
+     */
+    @Override
+    public Theme findById(Long id) {
+        log.info("查询主题详情，id={}", id);
+        Theme theme = themeMapper.selectById(id);
+        if (theme == null) {
+            log.warn("主题不存在，id={}", id);
+            throw new BusinessException("主题不存在");
+        }
+        return theme;
+    }
+
+    /**
+     * 创建主题
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public Theme create(String name, String description, Integer sortOrder) {
+        log.info("创建主题，name={}, sortOrder={}", name, sortOrder);
+        // 获取最大排序号
+        Integer maxSortOrder = themeMapper.selectList(null)
+                .stream()
+                .map(Theme::getSortOrder)
+                .max(Integer::compareTo)
+                .orElse(0);
+
+        Theme theme = new Theme();
+        theme.setName(name);
+        theme.setDescription(description);
+        theme.setSortOrder(sortOrder != null ? sortOrder : maxSortOrder + 1);
+        theme.setStatus("ACTIVE");
+        themeMapper.insert(theme);
+
+        log.info("主题创建成功，id={}", theme.getId());
+        return theme;
+    }
+
+    /**
+     * 更新主题
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public Theme update(Long id, String name, String description, Integer sortOrder, String status) {
+        log.info("更新主题，id={}, name={}, status={}", id, name, status);
+        Theme theme = themeMapper.selectById(id);
+        if (theme == null) {
+            log.warn("主题不存在，id={}", id);
+            throw new BusinessException("主题不存在");
+        }
+
+        if (name != null) {
+            theme.setName(name);
+        }
+        if (description != null) {
+            theme.setDescription(description);
+        }
+        if (sortOrder != null) {
+            theme.setSortOrder(sortOrder);
+        }
+        if (status != null) {
+            theme.setStatus(status);
+        }
+
+        themeMapper.updateById(theme);
+        log.info("主题更新成功，id={}", id);
+        return theme;
+    }
+
+    /**
+     * 删除主题
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void delete(Long id) {
+        log.info("删除主题，id={}", id);
+        // 检查是否有关联课程
+        Long courseCount = courseMapper.selectCount(
+                new LambdaQueryWrapper<CoursePackage>().eq(CoursePackage::getThemeId, id)
+        );
+
+        if (courseCount > 0) {
+            log.warn("删除主题失败，该主题下有 {} 个课程包，id={}", courseCount, id);
+            throw new BusinessException("该主题下有 " + courseCount + " 个课程包，无法删除");
+        }
+
+        themeMapper.deleteById(id);
+        log.info("主题删除成功，id={}", id);
+    }
+
+    /**
+     * 重新排序
+     */
+    @Override
+    @Transactional(rollbackFor = Exception.class)
+    public void reorder(List<Long> ids) {
+        log.info("重新排序主题，count={}", ids.size());
+        for (int i = 0; i < ids.size(); i++) {
+            Theme theme = themeMapper.selectById(ids.get(i));
+            if (theme != null) {
+                theme.setSortOrder(i + 1);
+                themeMapper.updateById(theme);
+            }
+        }
+        log.info("主题重新排序成功");
+    }
+}