课程-章节-课时顺序调整完成

Html/apps/services/course_service.py

@@ -112,6 +112,49 @@ def delete_material_chapter_lesson(material_id, chapter_name, lesson_name, teach
     # 如果删除操作成功，res.modified_count 应为 1
     return res.modified_count == 1
 
+def reorder_material_structure(material_id, order):
+    mongo = current_app.extensions["mongo"]
+    material = mongo.db.materials.find_one({'_id': ObjectId(material_id)})
+    if not material:
+        return False
+    chapter_map = {ch["chapter_name"]: ch for ch in material["chapters"]}
+    new_chapters = []
+    for chapter_order in order:
+        ch_name = chapter_order['chapter_name']
+        if ch_name not in chapter_map:
+            continue  # 如果前端传了不存在的章节名，可以选择跳过或报错
+        original_ch = chapter_map[ch_name]
+
+        # 建立 lesson_name -> lesson dict
+        lesson_map = {ls["lesson_name"]: ls for ls in original_ch["lessons"]}
+
+        # 按顺序重排 lessons
+        new_lessons = []
+        for ls_name in chapter_order['lessons']:
+            if ls_name in lesson_map:
+                new_lessons.append(lesson_map[ls_name])
+
+        # 如果还有遗漏（前端没传的），可以追加到最后，避免丢数据
+        for ls_name, ls in lesson_map.items():
+            if ls not in new_lessons:
+                new_lessons.append(ls)
+
+        # 构造新的 chapter
+        new_chapter = {**original_ch, "lessons": new_lessons}
+        new_chapters.append(new_chapter)
+
+    # 更新 material
+    mongo.db.materials.update_one(
+        {"_id": ObjectId(material_id)},
+        {
+            "$set": {
+                "chapters": new_chapters,
+                "updated_at": datetime.now()
+            }
+        }
+    )
+    return True
+
 def save_materials_markdown_cos(
     material_id: str,
     chapter_name: str,