refactor: better SerializersModule structure

All backend function is available

.idea/compiler.xml

@@ -2,12 +2,12 @@
 <project version="4">
   <component name="CompilerConfiguration">
     <bytecodeTargetLevel>
-      <module name="club.itstudio.itmanager.main" target="21" />
-      <module name="club.itstudio.itmanager.test" target="21" />
+      <module name="itmanager" target="25" />
     </bytecodeTargetLevel>
   </component>
   <component name="JavacSettings">
     <option name="ADDITIONAL_OPTIONS_OVERRIDE">
+      <module name="club.itstudio.itmanager" options="-parameters" />
       <module name="club.itstudio.itmanager.main" options="-parameters" />
       <module name="club.itstudio.itmanager.test" options="-parameters" />
       <module name="itmanager" options="-parameters" />

.idea/data_source_mapping.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="DataSourcePerFileMappings">
+    <file url="file://$PROJECT_DIR$/schema.sql" value="c13cb29f-8398-41b6-a24b-5cf0642c9759" />
+  </component>
+</project>

.idea/gradle.xml

@@ -4,10 +4,11 @@
   <component name="GradleSettings">
     <option name="linkedExternalProjectsSettings">
       <GradleProjectSettings>
-        <option name="externalProjectPath" value="$PROJECT_DIR$/src/beckend" />
+        <option name="externalProjectPath" value="$PROJECT_DIR$/src/backend" />
+        <option name="gradleJvm" value="ms-25" />
         <option name="modules">
           <set>
-            <option value="$PROJECT_DIR$/src/beckend" />
+            <option value="$PROJECT_DIR$/src/backend" />
           </set>
         </option>
       </GradleProjectSettings>

.idea/inspectionProfiles/Project_Default.xml

@@ -0,0 +1,20 @@
+<component name="InspectionProjectProfileManager">
+  <profile version="1.0">
+    <option name="myName" value="Project Default" />
+    <inspection_tool class="DuplicatedCode" enabled="true" level="WEAK WARNING" enabled_by_default="true">
+      <Languages>
+        <language minSize="49" name="Kotlin" />
+      </Languages>
+    </inspection_tool>
+    <inspection_tool class="PyShadowingBuiltinsInspection" enabled="true" level="WEAK WARNING" enabled_by_default="true">
+      <option name="ignoredNames">
+        <list>
+          <option value="id" />
+        </list>
+      </option>
+    </inspection_tool>
+    <inspection_tool class="ShellCheck" enabled="true" level="ERROR" enabled_by_default="true">
+      <shellcheck_settings value="SC2317" />
+    </inspection_tool>
+  </profile>
+</component>

.idea/itstudio_manager.iml

@@ -3,8 +3,9 @@
   <component name="NewModuleRootManager" inherit-compiler-output="true">
     <exclude-output />
     <content url="file://$MODULE_DIR$">
-      <excludeFolder url="file://$MODULE_DIR$/src/beckend/.kotlin" />
-      <excludeFolder url="file://$MODULE_DIR$/src/beckend/build" />
+      <excludeFolder url="file://$MODULE_DIR$/src/backend/.kotlin" />
+      <excludeFolder url="file://$MODULE_DIR$/src/backend/build" />
+      <excludeFolder url="file://$MODULE_DIR$/.idea/dataSources" />
     </content>
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />

.idea/kotlinc.xml

@@ -6,12 +6,8 @@
   <component name="Kotlin2JvmCompilerArguments">
     <option name="jvmTarget" value="21" />
   </component>
-  <component name="KotlinCommonCompilerArguments">
-    <option name="apiVersion" value="2.2" />
-    <option name="languageVersion" value="2.2" />
-  </component>
   <component name="KotlinJpsPluginSettings">
     <option name="externalSystemId" value="Gradle" />
-    <option name="version" value="2.2.21" />
+    <option name="version" value="2.4.20-RC" />
   </component>
 </project>

.idea/misc.xml

@@ -2,7 +2,7 @@
 <project version="4">
   <component name="ExternalStorageConfigurationManager" enabled="true" />
   <component name="FrameworkDetectionExcludesConfiguration">
-    <file type="web" url="file://$PROJECT_DIR$/src/beckend" />
+    <file type="web" url="file://$PROJECT_DIR$/src/backend" />
   </component>
   <component name="ProjectRootManager" version="2" languageLevel="JDK_25" project-jdk-name="ms-25" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />

.idea/sqldialects.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="SqlDialectMappings">
+    <file url="file://$PROJECT_DIR$/schema.sql" dialect="MariaDB" />
+  </component>
+</project>

API.md

@@ -1,44 +1,76 @@
-# http://localhost:8080/api
+# API 文档
 
-所有返回的json对象总有如下格式
+Base URL：`http://localhost:8080/api`
+
+## 通用约定
+
+所有接口均返回统一 JSON 结构：
 
 ```typescript
-class respose<T> {
+class Response<T> {
     "code": number;
     "message": string;
-    "data": T
+    "data": T | null;
 }
 ```
 
-接下来将省略`/api`并只给出`T`的类声明
+- `code === 200` 表示成功；**`code !== 200` 时 `data` 恒为 `null`**
+- 除特别标注（公开）外，接口需在请求头携带 `Authorization: Bearer <token>`
+- 下文路径均省略 `/api` 前缀，`data` 仅给出 `T` 的声明
+- 部分 `/test` 接口的返回值不遵循上述格式
+- 前端类示例使用 **TypeScript** 类定义
 
-当`"code"`不是`200`时，`"data"`必定为`null`
+## 接口总览
 
-部分`/api/test`的返回值不遵循上述格式
+| 分组         | 路径前缀           | 说明                                      |
+|--------------|--------------------|-------------------------------------------|
+| 测试         | `/test`            | 连通性测试                                |
+| 认证         | `/v1/auth`         | 登录 / 注册 / 验证码 / Token 管理         |
+| 物品管理     | `/v1/items`        | 物品 / 类别 / 图片 CRUD、借还、上下架查询 |
+| 使用记录     | `/v1/usages`       | 使用记录 CRUD、图片、当前/按用户查询      |
+| 财务管理     | `/v1/finance`      | 财务记录 / 分类 CRUD、凭证图片上传        |
+| 财务凭证图片 | `/v1/proof-images` | 财务凭证图片 CRUD                         |
+| 邮件通知     | `/v1/email`        | 通知设置、收件邮箱启用状态                |
 
-## /test
+---
+
+## 分组：测试 `/test`
 
 ### GET /hello
 
-Authorization: Bearer $Token
+需要认证。
 
-key: 无
-
-回复：
+**响应**
 
 ```typescript
 "Hello Kotlin WebFlux!"
 ```
 
-## /v1/auth
+---
+
+## 分组：认证 `/v1/auth`
+
+| 方法   | 路径                      | 认证 | 说明                     |
+|--------|---------------------------|------|--------------------------|
+| POST   | `/login`                  | 公开 | 登录，获取 Token         |
+| GET    | `/logout`                 | 需要 | 注销，Token 加入黑名单   |
+| GET    | `/ask-code`               | 公开 | 发送邮箱验证码           |
+| POST   | `/register`               | 公开 | 邮箱注册                 |
+| POST   | `/reset`                  | 公开 | 重置密码                 |
+| GET    | `/relogin`                | 需要 | 用旧 Token 换取新 Token  |
 
 ### POST /login
 
-Authorization: 无
+以 `application/x-www-form-urlencoded` 表单提交。
 
-key: username, password
+**请求参数**
 
-data：
+| 字段     | 类型   | 说明     |
+|----------|--------|----------|
+| username | string | 用户名   |
+| password | string | 密码     |
+
+**响应 data**
 
 ```typescript
 class data {
@@ -51,79 +83,608 @@ class data {
 
 ### GET /logout
 
-Authorization: Bearer $Token
+**请求参数**：无
 
-key: 无
+**响应 data**：`null`
 
-data：
+### GET /ask-code
 
-```typescript
-null
-```
+**请求参数**
 
-### GET /ask-code?email=******&type=register
+| 字段  | 类型                        | 说明                               |
+|-------|-----------------------------|------------------------------------|
+| email | string                      | 接收验证码的邮箱                   |
+| type  | `register` \| `reset`       | 验证码用途（注册 / 重置密码）      |
 
-Authorization: 无
-
-key: 无
-
-data：
-
-```typescript
-null
-```
-
-### GET /ask-code?email=******&type=reset
-
-Authorization: 无
-
-key: 无
-
-data：
-
-```typescript
-null
-```
+**响应 data**：`null`
 
 ### POST /register
 
-Authorization: 无
+**请求体字段**：`email`、`code`、`username`、`password`
 
-key: 无
-
-data：email, code, username, password
-
-```typescript
-null
-```
+**响应 data**：`null`
 
 ### POST /reset
 
-Authorization: 无
+**请求体字段**：`email`、`code`、`password`
 
-key: email, code, password
-
-data：
-
-```typescript
-null
-```
+**响应 data**：`null`
 
 ### GET /relogin
 
-Authorization: Bearer $Token
+**请求参数**：无
 
-key: 无
-
-data：
+**响应 data**
 
 ```typescript
 class data {
-    "token": sting;
-    "expire": time
+    "token": string;
+    "expire": Date;
 }
 ```
 
-# ws://localhost:8080/ws
+---
 
-目前不支持WS
+## 分组：物品管理 `/v1/items`
+
+| 方法   | 路径                            | 认证 | 说明                                   |
+|--------|---------------------------------|------|----------------------------------------|
+| GET    | `/items`                        | 需要 | 分页查询物品                           |
+| POST   | `/items`                        | 需要 | 创建物品                               |
+| PUT    | `/items`                        | 需要 | 更新物品                               |
+| DELETE | `/items`                        | 需要 | 删除物品（同时清理其图片）             |
+| POST   | `/items/{id}/upload_images`     | 需要 | 上传物品图片（multipart）              |
+| POST   | `/items/{id}/set_primary_image` | 需要 | 设置物品主图                           |
+| POST   | `/items/{id}/borrow`            | 需要 | 借用物品（扣减可用库存）               |
+| POST   | `/items/{id}/return_item`       | 需要 | 归还物品（恢复可用库存）               |
+| GET    | `/items/available`              | 需要 | 获取可用物品列表                       |
+| GET    | `/items/in_use`                 | 需要 | 获取使用中物品列表                     |
+| GET    | `/items/categories`             | 需要 | 查询物品类别列表                       |
+| POST   | `/items/categories`             | 需要 | 创建物品类别                           |
+| PUT    | `/items/categories`             | 需要 | 更新物品类别                           |
+| DELETE | `/items/categories`             | 需要 | 删除物品类别                           |
+| GET    | `/items/images`                 | 需要 | 查询物品图片列表                       |
+| POST   | `/items/images`                 | 需要 | 创建物品图片                           |
+| PUT    | `/items/images`                 | 需要 | 更新物品图片                           |
+| DELETE | `/items/images`                 | 需要 | 删除物品图片（同时删除物理文件）       |
+
+### 实体定义
+
+```typescript
+class Item {
+    "id": number | null;
+    "code": string;                 // 物品编号 / 资产编号
+    "name": string;
+    "categoryId": number | null;
+    "model": string | null;
+    "brand": string | null;
+    "location": string | null;
+    "totalQuantity": number;
+    "availableQuantity": number;
+    "unit": string;                 // 默认 "件"
+    "price": number | null;
+    "purchaseDate": string | null;
+    "supplier": string | null;
+    "status": string;               // normal / disabled / lost / repair
+    "description": string | null;
+    "imagePath": string | null;
+    "createdBy": number | null;
+    "createdAt": string | null;
+    "updatedAt": string | null;
+}
+```
+
+```typescript
+class Category {
+    "id": number | null;
+    "name": string;
+    "parentId": number | null;
+    "description": string | null;
+    "createdAt": string | null;
+    "updatedAt": string | null;
+}
+```
+
+```typescript
+class Attachment {
+    "id": number | null;
+    "relatedTable": string | null;  // 关联表名，如 "items"
+    "relatedId": number | null;     // 关联记录 ID
+    "fileName": string | null;
+    "filePath": string | null;
+    "fileSize": number | null;
+    "contentType": string | null;
+    "uploadedBy": number | null;
+    "uploadedAt": string | null;
+}
+```
+
+```typescript
+class Page<T> {
+    "records": T[];
+    "total": number;
+    "size": number;
+    "current": number;
+    "pages": number;
+}
+```
+
+### GET /items
+
+**请求参数**
+
+| 字段     | 类型    | 说明                              |
+|----------|---------|-----------------------------------|
+| pageNum  | number  | 页码，默认 `1`                    |
+| pageSize | number  | 每页条数，默认 `10`               |
+| keyword  | string? | 按名称 / 编号模糊搜索             |
+| status   | string? | 按状态过滤，如 `normal`           |
+
+**响应 data**：`Page<Item>`
+
+### POST /items
+
+**请求体**：`Item`（`id` / `createdAt` / `updatedAt` 由服务端填充）
+
+**响应 data**：`null`
+
+### PUT /items
+
+**请求体**：`Item`（须包含 `id`）
+
+**响应 data**：`null`
+
+### DELETE /items
+
+**请求参数**
+
+| 字段 | 类型   | 说明    |
+|------|--------|---------|
+| id   | number | 物品 ID |
+
+**响应 data**：`null`
+
+### POST /items/{id}/upload_images
+
+**请求**：`multipart/form-data`，字段名 `files`，可传多个图片文件
+
+**响应 data**：`null`
+
+### POST /items/{id}/set_primary_image
+
+**请求参数**
+
+| 字段    | 类型   | 说明                                     |
+|---------|--------|------------------------------------------|
+| imageId | number | 附件 ID，须属于该物品                    |
+
+**响应 data**：`null`
+
+### POST /items/{id}/borrow
+
+**请求参数**
+
+| 字段     | 类型   | 说明               |
+|----------|--------|--------------------|
+| quantity | number | 借用数量，默认 `1` |
+
+**响应 data**：`null`
+
+### POST /items/{id}/return_item
+
+**请求参数**
+
+| 字段     | 类型   | 说明               |
+|----------|--------|--------------------|
+| quantity | number | 归还数量，默认 `1` |
+
+**响应 data**：`null`
+
+### GET /items/available
+
+**请求参数**：无
+
+**响应 data**：`Item[]`
+
+### GET /items/in_use
+
+**请求参数**：无
+
+**响应 data**：`Item[]`
+
+### GET /items/categories
+
+**请求参数**：无
+
+**响应 data**：`Category[]`
+
+### POST /items/categories
+
+**请求体**：`Category`（`id` / `createdAt` / `updatedAt` 由服务端填充）
+
+**响应 data**：`null`
+
+### PUT /items/categories
+
+**请求体**：`Category`（须包含 `id`）
+
+**响应 data**：`null`
+
+### DELETE /items/categories
+
+**请求参数**
+
+| 字段 | 类型   | 说明     |
+|------|--------|----------|
+| id   | number | 类别 ID  |
+
+**响应 data**：`null`
+
+### GET /items/images
+
+**请求参数**：无
+
+**响应 data**：`Attachment[]`（`relatedTable` 为 `"items"` 的图片）
+
+### POST /items/images
+
+**请求体**：`Attachment`（`id` / `uploadedAt` 由服务端填充）
+
+**响应 data**：`null`
+
+### PUT /items/images
+
+**请求体**：`Attachment`（须包含 `id`）
+
+**响应 data**：`null`
+
+### DELETE /items/images
+
+**请求参数**
+
+| 字段 | 类型   | 说明     |
+|------|--------|----------|
+| id   | number | 图片 ID  |
+
+**响应 data**：`null`
+
+---
+
+## 分组：使用记录 `/v1/usages`
+
+| 方法   | 路径                         | 认证 | 说明                                 |
+|--------|------------------------------|------|--------------------------------------|
+| GET    | `/usages`                    | 需要 | 分页查询使用记录                     |
+| POST   | `/usages`                    | 需要 | 创建使用记录                         |
+| PUT    | `/usages`                    | 需要 | 更新使用记录                         |
+| DELETE | `/usages`                    | 需要 | 删除使用记录                         |
+| POST   | `/usages/{id}/upload_images` | 需要 | 上传使用记录图片（multipart）        |
+| GET    | `/usages/current`            | 需要 | 获取当前使用中的记录                 |
+| GET    | `/usages/by_user`            | 需要 | 根据用户姓名获取使用记录             |
+| GET    | `/usages/images`             | 需要 | 查询使用记录图片列表                 |
+| POST   | `/usages/images`             | 需要 | 创建使用记录图片                     |
+| PUT    | `/usages/images`             | 需要 | 更新使用记录图片                     |
+| DELETE | `/usages/images`             | 需要 | 删除使用记录图片（同时删除物理文件） |
+
+### 实体定义
+
+```typescript
+class BorrowRecord {
+    "id": number | null;
+    "itemId": number;
+    "borrower": string;
+    "quantity": number;
+    "borrowDate": string | null;
+    "dueDate": string | null;
+    "returnDate": string | null;
+    "status": string;          // BORROWED / RETURNED / OVERDUE / CANCELED
+    "approver": string | null;
+    "note": string | null;
+    "createdAt": string | null;
+    "updatedAt": string | null;
+}
+```
+
+### GET /usages
+
+**请求参数**
+
+| 字段     | 类型    | 说明                |
+|----------|---------|---------------------|
+| pageNum  | number  | 页码，默认 `1`      |
+| pageSize | number  | 每页条数，默认 `10` |
+| keyword  | string? | 按借入人模糊搜索    |
+| status   | string? | 按状态过滤          |
+
+**响应 data**：`Page<BorrowRecord>`
+
+### POST /usages
+
+**请求体**：`BorrowRecord`（`id` / `createdAt` / `updatedAt` 由服务端填充）
+
+**响应 data**：`null`
+
+### PUT /usages
+
+**请求体**：`BorrowRecord`（须包含 `id`）
+
+**响应 data**：`null`
+
+### DELETE /usages
+
+**请求参数**
+
+| 字段 | 类型   | 说明    |
+|------|--------|---------|
+| id   | number | 记录 ID |
+
+**响应 data**：`null`
+
+### POST /usages/{id}/upload_images
+
+**请求**：`multipart/form-data`，字段名 `files`，可传多个图片文件
+
+**响应 data**：`null`
+
+### GET /usages/current
+
+**请求参数**：无
+
+**响应 data**：`BorrowRecord[]`（当前 `BORROWED` 与 `OVERDUE` 记录）
+
+### GET /usages/by_user
+
+**请求参数**
+
+| 字段 | 类型    | 说明       |
+|------|---------|------------|
+| name | string? | 借入人姓名 |
+
+**响应 data**：`BorrowRecord[]`
+
+### GET /usages/images
+
+**请求参数**：无
+
+**响应 data**：`Attachment[]`（`relatedTable` 为 `"borrow_records"` 的图片）
+
+### POST /usages/images
+
+**请求体**：`Attachment`（`id` / `uploadedAt` 由服务端填充）
+
+**响应 data**：`null`
+
+### PUT /usages/images
+
+**请求体**：`Attachment`（须包含 `id`）
+
+**响应 data**：`null`
+
+### DELETE /usages/images
+
+**请求参数**
+
+| 字段 | 类型   | 说明     |
+|------|--------|----------|
+| id   | number | 图片 ID  |
+
+**响应 data**：`null`
+
+---
+
+## 分组：财务管理 `/v1/finance`
+
+| 方法   | 路径                          | 认证 | 说明                                  |
+|--------|-------------------------------|------|---------------------------------------|
+| GET    | `/finance`                    | 需要 | 分页查询财务记录                      |
+| POST   | `/finance`                    | 需要 | 创建财务记录                          |
+| PUT    | `/finance`                    | 需要 | 更新财务记录                          |
+| DELETE | `/finance`                    | 需要 | 删除财务记录                          |
+| POST   | `/finance/{id}/upload_images` | 需要 | 上传财务凭证图片（multipart）         |
+| DELETE | `/finance/{id}`               | 需要 | 删除财务记录（发送邮件通知）          |
+| GET    | `/finance/categories`         | 需要 | 查询财务分类列表                      |
+| POST   | `/finance/categories`         | 需要 | 创建财务分类                          |
+| PUT    | `/finance/categories`         | 需要 | 更新财务分类                          |
+| DELETE | `/finance/categories`         | 需要 | 删除财务分类                          |
+
+### 实体定义
+
+```typescript
+class FinanceRecord {
+    "id": number | null;
+    "recordNo": string | null;
+    "type": string;              // PURCHASE / REFUND / REPAIR / DEPRECIATION / OTHER
+    "relatedItemId": number | null;
+    "amount": number;            // BigDecimal
+    "currency": string;          // 默认 "CNY"
+    "vendor": string | null;
+    "occurredAt": string | null;
+    "recordedBy": number | null;
+    "note": string | null;
+    "createdAt": string | null;
+}
+```
+
+### GET /finance
+
+**请求参数**
+
+| 字段     | 类型    | 说明                           |
+|----------|---------|--------------------------------|
+| pageNum  | number  | 页码，默认 `1`                 |
+| pageSize | number  | 每页条数，默认 `10`            |
+| keyword  | string? | 按单号 / 供应商 / 备注模糊搜索 |
+| type     | string? | 按类型过滤                     |
+| start    | string? | 发生时间起点                   |
+| end      | string? | 发生时间终点                   |
+| vendor   | string? | 按供应商过滤                   |
+| itemId   | number? | 按关联物品 ID 过滤             |
+
+**响应 data**：`Page<FinanceRecord>`
+
+### POST /finance
+
+**请求体**：`FinanceRecord`（`id` / `createdAt` 由服务端填充）
+
+**响应 data**：`null`
+
+### PUT /finance
+
+**请求体**：`FinanceRecord`（须包含 `id`）
+
+**响应 data**：`null`
+
+### DELETE /finance
+
+**请求参数**
+
+| 字段 | 类型   | 说明    |
+|------|--------|---------|
+| id   | number | 记录 ID |
+
+**响应 data**：`null`
+
+### POST /finance/{id}/upload_images
+
+**请求**：`multipart/form-data`，字段名 `files`，可传多个图片文件
+
+**响应 data**：`null`
+
+### DELETE /finance/{id}
+
+删除财务记录，并向 `recordedBy` 对应账号的邮箱发送删除通知。
+
+**响应 data**：`null`
+
+### GET /finance/categories
+
+**请求参数**：无
+
+**响应 data**：`Category[]`
+
+### POST /finance/categories
+
+**请求体**：`Category`（`id` / `createdAt` / `updatedAt` 由服务端填充）
+
+**响应 data**：`null`
+
+### PUT /finance/categories
+
+**请求体**：`Category`（须包含 `id`）
+
+**响应 data**：`null`
+
+### DELETE /finance/categories
+
+**请求参数**
+
+| 字段 | 类型   | 说明     |
+|------|--------|----------|
+| id   | number | 分类 ID  |
+
+**响应 data**：`null`
+
+---
+
+## 分组：财务凭证图片 `/v1/proof-images`
+
+| 方法   | 路径                   | 认证 | 说明                              |
+|--------|------------------------|------|-----------------------------------|
+| GET    | `/proof-images`        | 需要 | 查询财务凭证图片列表              |
+| POST   | `/proof-images`        | 需要 | 创建财务凭证图片                  |
+| PUT    | `/proof-images`        | 需要 | 更新财务凭证图片                  |
+| DELETE | `/proof-images`        | 需要 | 删除财务凭证图片                  |
+| DELETE | `/proof-images/{id}`   | 需要 | 删除凭证图片（同时删除物理文件）  |
+
+凭证图片为 `relatedTable` 为 `"finance_records"` 的 `Attachment`，与 `/items/images` 共用 `Attachment` 实体。
+
+### GET /proof-images
+
+**请求参数**：无
+
+**响应 data**：`Attachment[]`
+
+### POST /proof-images
+
+**请求体**：`Attachment`（`id` / `uploadedAt` 由服务端填充）
+
+**响应 data**：`null`
+
+### PUT /proof-images
+
+**请求体**：`Attachment`（须包含 `id`）
+
+**响应 data**：`null`
+
+### DELETE /proof-images
+
+**请求参数**
+
+| 字段 | 类型   | 说明     |
+|------|--------|----------|
+| id   | number | 图片 ID  |
+
+**响应 data**：`null`
+
+### DELETE /proof-images/{id}
+
+删除图片并清理物理文件。
+
+**响应 data**：`null`
+
+---
+
+## 分组：邮件通知 `/v1/email`
+
+| 方法   | 路径                     | 认证 | 说明                    |
+|--------|--------------------------|------|-------------------------|
+| GET    | `/notification-settings` | 需要 | 获取通知设置和邮箱列表  |
+| POST   | `/notification-settings` | 需要 | 创建 / 更新通知设置     |
+| POST   | `/toggle-email-status`   | 需要 | 切换邮箱启用 / 禁用状态 |
+
+### 实体定义
+
+```typescript
+class EmailNotice {
+    "id": number | null;
+    "name": string | null;
+    "targetEmails": string | null;
+    "subject": string | null;
+    "body": string | null;
+    "enabled": boolean;              // 默认 true
+    "scheduleCron": string | null;
+    "lastSentAt": string | null;
+    "createdAt": string | null;
+    "updatedAt": string | null;
+}
+```
+
+### GET /notification-settings
+
+**请求参数**：无
+
+**响应 data**：`EmailNotice[]`
+
+### POST /notification-settings
+
+**请求体**：`EmailNotice`。`id` 为 `null` 时创建新记录，否则更新已有记录。
+
+**响应 data**：`null`
+
+### POST /toggle-email-status
+
+**请求参数**
+
+| 字段 | 类型    | 说明     |
+|------|---------|----------|
+| id   | number? | 通知 ID  |
+
+**响应 data**：`null`
+
+---
+
+## 其他
+
+### WebSocket
+
+`ws://localhost:8080/ws` — 目前不支持

README.md

@@ -5,141 +5,72 @@
 [完整信息](./API.md)
 
 - /api
-  - /test
-    - /hello
-  - /v1
-    - /auth
-      - /login
-      - /logout
-      - /relogin
-      - /ask-code
-      - /register
-      - /reset
-    - /departments
-    - /email
-    - /evaluation-records
-    - /finance
-    - /items
-    - /memos
-    - /personnel
-    - /project-groups
-    - /proof-images
-    - /usages
+    - /test
+        - /hello
+    - /v1
+        - /auth
+            - /login
+            - /logout
+            - /relogin
+            - /ask-code
+            - /register
+            - /reset
+        - /email
+            - /notification-settings
+            - /toggle-email-status
+        - /finance
+            - /
+            - /{id}/upload_images
+            - /{id}
+            - /categories
+        - /items
+            - /
+            - /{id}/upload_images
+            - /{id}/set_primary_image
+            - /{id}/borrow
+            - /{id}/return_item
+            - /available
+            - /in_use
+            - /categories
+            - /images
+        - /proof-images
+            - /
+            - /{id}
+        - /usages
+            - /
+            - /{id}/upload_images
+            - /current
+            - /by_user
+            - /images
 
-## 预计完成的 API 列表
+#### 认证方式
 
-### 1. **物品管理 (Items)** - `/api/`
+所有 API 均使用 **JWT 认证**（除了需要特殊处理的端点）
 
-| 端点                              | 方法                  | 功能说明           |
-|---------------------------------|---------------------|----------------|
-| `items/`                        | GET/POST/PUT/DELETE | 物品 CRUD 操作     |
-| `items/{id}/upload_images/`     | POST                | 上传物品图片         |
-| `items/{id}/set_primary_image/` | POST                | 设置主图片          |
-| `items/{id}/borrow/`            | POST                | 借用物品           |
-| `items/{id}/return_item/`       | POST                | 归还物品           |
-| `items/available/`              | GET                 | 获取可用物品列表       |
-| `items/in_use/`                 | GET                 | 获取使用中的物品列表     |
-| `usages/`                       | GET/POST/PUT/DELETE | 物品使用记录 CRUD 操作 |
-| `usages/{id}/upload_images/`    | POST                | 上传使用记录图片       |
-| `usages/current/`               | GET                 | 获取当前使用中的记录     |
-| `usages/by_user/`               | GET                 | 根据用户姓名获取使用记录   |
-| `item_categories/`              | GET/POST/PUT/DELETE | 物品类别 CRUD 操作   |
-| `users/`                        | GET                 | 获取用户列表（只读）     |
-| `item-images/`                  | GET/POST/PUT/DELETE | 物品图片 CRUD 操作   |
-| `usage-images/`                 | GET/POST/PUT/DELETE | 使用记录图片 CRUD 操作 |
-
----
-
-### 2. **人员管理 (Personnel)** - `/api/`
-
-| 端点                              | 方法                  | 功能说明             |
-|---------------------------------|---------------------|------------------|
-| `personnel/`                    | GET/POST/PUT/DELETE | 人员信息 CRUD 操作     |
-| `personnel/statistics/`         | GET                 | 获取人员统计信息（按部门和职位） |
-| `personnel/{id}/set_inactive/`  | POST                | 设置人员为已卸任状态       |
-| `personnel/{id}/set_active/`    | POST                | 设置人员为在职状态        |
-| `personnel/{id}/`               | DELETE              | 删除人员（发送邮件通知）     |
-| `personnel/check_expired/`      | POST                | 检查并更新已到期的人员状态    |
-| `project-groups/`               | GET/POST/PUT/DELETE | 项目组 CRUD 操作      |
-| `project-groups/by_department/` | GET                 | 按部门获取项目组         |
-| `project-groups/{id}/`          | DELETE              | 删除项目组（发送邮件通知）    |
-
-**搜索/过滤字段**: `name`, `student_id`, `phone`, `email`, `grade_major`
-
----
-
-### 3. **财务管理 (Finance)** - `/api/`
-
-| 端点                            | 方法                  | 功能说明             |
-|-------------------------------|---------------------|------------------|
-| `finance/`                    | GET/POST/PUT/DELETE | 财务记录 CRUD 操作     |
-| `finance/{id}/upload_images/` | POST                | 上传财务凭证图片         |
-| `finance/{id}/`               | DELETE              | 删除财务记录（发送邮件通知）   |
-| `departments/`                | GET/POST/PUT/DELETE | 部门 CRUD 操作       |
-| `departments/{id}/`           | DELETE              | 删除部门（发送邮件通知）     |
-| `finance_categories/`         | GET/POST/PUT/DELETE | 财务分类 CRUD 操作     |
-| `proof-images/`               | GET/POST/PUT/DELETE | 财务凭证图片 CRUD 操作   |
-| `proof-images/{id}/`          | DELETE              | 删除凭证图片（自动删除物理文件） |
-
----
-
-### 4. **邮件通知 (Email Notice)** - `/api/`
-
-| 端点                       | 方法       | 功能说明           |
-|--------------------------|----------|----------------|
-| `notification-settings/` | GET/POST | 获取/更新通知设置和邮箱列表 |
-| `toggle-email-status/`   | POST     | 切换邮箱启用/禁用状态    |
-
-**功能**: 管理邮件通知的全局开关和收件人列表
-
----
-
-### 5. **备忘录 (Memo)** - `/api/`
-
-| 端点                         | 方法                  | 功能说明        |
-|----------------------------|---------------------|-------------|
-| `memos/`                   | GET/POST/PUT/DELETE | 备忘录 CRUD 操作 |
-| `memos/{id}/upload_image/` | POST                | 上传备忘录图片     |
-| `memos/{id}/delete_image/` | DELETE              | 删除备忘录图片     |
-
-**搜索字段**: `title`, `content`  
-**默认排序**: 按更新时间倒序
-
----
-
-### 6. **考评系统 (Evaluation)** - `/api/`
-
-| 端点                                      | 方法                  | 功能说明                   |
-|-----------------------------------------|---------------------|------------------------|
-| `evaluation-records/`                   | GET/POST/PUT/DELETE | 考评记录 CRUD 操作           |
-| `evaluation-records/personnel-summary/` | GET                 | 获取人员考评汇总（按人员、部门、年级分组）  |
-| `evaluation-records/personnel-records/` | GET                 | 获取某个人员的所有考评记录          |
-| `evaluation-records/delete-personnel/`  | DELETE              | 删除某个人员的所有考评记录          |
-| `evaluation-records/export/`            | GET                 | 导出考评记录为 Excel（每个人一个表格） |
-| `evaluation-records/download-template/` | GET                 | 下载人员导入样表               |
-| `evaluation-records/import/`            | POST                | 导入考评记录（支持 Excel/CSV）   |
-
-**功能**:
-- 支持批量导入和导出
-- 样表格式：只需部门、年级、姓名（初始分39分）
-- 完整格式：包含详细的加分/扣分记录
-- 所有操作发送邮件通知
-
----
-
-### 7. **认证相关**
-
-| 端点                   | 方法       | 功能说明        |
-|----------------------|----------|-------------|
-| `api/token/`         | POST     | JWT 令牌获取    |
-| `api/token/refresh/` | POST     | JWT 令牌刷新    |
-| `admin/`             | GET/POST | Django 管理后台 |
-
----
-
-## 认证方式
-
-所有 API 均使用 **JWT 认证**（除了需要特殊处理的端点）：
 ```
 Authorization: Bearer <token>
 ```
+
+## 数据库结构
+
+[schema.sql](./schema.sql)
+
+- users/account (系统用户/认证信息)
+- categories (物品类别)
+    - parent_id -> categories.id (自关联父级)
+- items (物品基本信息)
+    - category_id -> categories.id
+    - created_by -> account.id
+- item_transactions (物品出入库流水)
+    - item_id -> items.id (ON DELETE CASCADE)
+    - operator_id -> account.id
+- borrow_records (借用/归还记录)
+    - item_id -> items.id (ON DELETE CASCADE)
+    - borrower (借入人，字符串)
+    - approver (借出/审批人，字符串)
+- finance_records (财务相关记录)
+    - related_item_id -> items.id
+    - recorded_by -> account.id
+- email_notices (邮件通知规则/历史)
+- attachments (文件附件存储索引表)
+    - uploaded_by -> account.id

schema.sql

@@ -0,0 +1,159 @@
+-- 用户表（若项目使用 Django auth，可忽略或与 auth_user 对应）
+DROP TABLE IF EXISTS account;
+CREATE TABLE account
+(
+    id         BIGINT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
+    username   VARCHAR(150)    NOT NULL UNIQUE,
+    password   VARCHAR(128)    NOT NULL,
+    email      VARCHAR(254),
+    full_name  VARCHAR(200),
+    is_active  TINYINT(1)      NOT NULL DEFAULT 1,
+    is_staff   TINYINT(1)      NOT NULL DEFAULT 0,
+    created_at DATETIME        NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at DATETIME        NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
+) ENGINE = InnoDB
+  DEFAULT CHARSET = utf8mb4
+  COLLATE = utf8mb4_unicode_ci COMMENT ='系统用户/认证信息';
+
+-- 物品类别
+DROP TABLE IF EXISTS categories;
+CREATE TABLE categories
+(
+    id          BIGINT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
+    name        VARCHAR(150)    NOT NULL,
+    parent_id   BIGINT UNSIGNED,
+    description TEXT,
+    created_at  DATETIME        NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at  DATETIME        NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+    CONSTRAINT fk_categories_parent FOREIGN KEY (parent_id) REFERENCES categories (id) ON DELETE SET NULL
+) ENGINE = InnoDB
+  DEFAULT CHARSET = utf8mb4 COMMENT ='物品类别';
+
+-- 物品（物品主表）
+DROP TABLE IF EXISTS items;
+CREATE TABLE items
+(
+    id                 BIGINT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
+    code               VARCHAR(100)    NOT NULL UNIQUE,           -- 物品编号/资产编号
+    name               VARCHAR(200)    NOT NULL,
+    category_id        BIGINT UNSIGNED,
+    model              VARCHAR(150),
+    brand              VARCHAR(150),
+    location           VARCHAR(200),
+    total_quantity     INT             NOT NULL DEFAULT 0,
+    available_quantity INT             NOT NULL DEFAULT 0,
+    unit               VARCHAR(30)              DEFAULT '件',
+    price              DECIMAL(12, 2)           DEFAULT NULL,
+    purchase_date      DATE                     DEFAULT NULL,
+    supplier           VARCHAR(200)             DEFAULT NULL,
+    status             VARCHAR(50)              DEFAULT 'normal', -- 如 normal/disabled/lost/repair
+    description        TEXT,
+    image_path         VARCHAR(500),
+    created_by         BIGINT UNSIGNED, -- 关联 account.id
+    created_at         DATETIME        NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at         DATETIME        NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+    CONSTRAINT fk_items_category FOREIGN KEY (category_id) REFERENCES categories (id) ON DELETE SET NULL,
+    CONSTRAINT fk_items_creator FOREIGN KEY (created_by) REFERENCES account (id) ON DELETE SET NULL,
+    INDEX (name),
+    INDEX (code)
+) ENGINE = InnoDB
+  DEFAULT CHARSET = utf8mb4 COMMENT ='物品基本信息';
+
+-- 物品库存/流水（每次入库/出库/调整都记录）
+DROP TABLE IF EXISTS item_transactions;
+CREATE TABLE item_transactions
+(
+    id            BIGINT UNSIGNED                       NOT NULL AUTO_INCREMENT PRIMARY KEY,
+    item_id       BIGINT UNSIGNED                       NOT NULL,
+    trans_type    ENUM ('IN','OUT','ADJUST','TRANSFER') NOT NULL,
+    quantity      INT                                   NOT NULL,
+    from_location VARCHAR(200),
+    to_location   VARCHAR(200),
+    related_id    BIGINT UNSIGNED, -- 可关联采购单/借用记录/调拨单 id
+    operator_id   BIGINT UNSIGNED, -- 关联 account.id（操作者）
+    note          TEXT,
+    created_at    DATETIME                              NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_trans_item FOREIGN KEY (item_id) REFERENCES items (id) ON DELETE CASCADE,
+    CONSTRAINT fk_trans_operator FOREIGN KEY (operator_id) REFERENCES account (id) ON DELETE SET NULL,
+    INDEX (item_id),
+    INDEX (trans_type)
+) ENGINE = InnoDB
+  DEFAULT CHARSET = utf8mb4 COMMENT ='物品出入库与调整流水';
+
+-- 借用记录（借/还）
+DROP TABLE IF EXISTS borrow_records;
+CREATE TABLE borrow_records
+(
+    id          BIGINT UNSIGNED                                   NOT NULL AUTO_INCREMENT PRIMARY KEY,
+    item_id     BIGINT UNSIGNED                                   NOT NULL,
+    borrower    VARCHAR(100)                                      NOT NULL, -- 借入人（姓名，字符串）
+    quantity    INT                                               NOT NULL DEFAULT 1,
+    borrow_date DATETIME                                          NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    due_date    DATETIME                                                   DEFAULT NULL,
+    return_date DATETIME                                                   DEFAULT NULL,
+    status      ENUM ('BORROWED','RETURNED','OVERDUE','CANCELED') NOT NULL DEFAULT 'BORROWED',
+    approver    VARCHAR(100)                                                DEFAULT NULL, -- 借出/审批人（姓名，字符串）
+    note        TEXT,
+    created_at  DATETIME                                          NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at  DATETIME                                          NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+    CONSTRAINT fk_borrow_item FOREIGN KEY (item_id) REFERENCES items (id) ON DELETE CASCADE,
+    INDEX (borrower),
+    INDEX (status)
+) ENGINE = InnoDB
+  DEFAULT CHARSET = utf8mb4 COMMENT ='借用/归还记录';
+
+-- 财务记录（采购/报销等）
+DROP TABLE IF EXISTS finance_records;
+CREATE TABLE finance_records
+(
+    id              BIGINT UNSIGNED                                            NOT NULL AUTO_INCREMENT PRIMARY KEY,
+    record_no       VARCHAR(100) UNIQUE,
+    type            ENUM ('PURCHASE','REFUND','REPAIR','DEPRECIATION','OTHER') NOT NULL,
+    related_item_id BIGINT UNSIGNED,
+    amount          DECIMAL(14, 2)                                             NOT NULL DEFAULT 0.00,
+    currency        VARCHAR(10)                                                         DEFAULT 'CNY',
+    vendor          VARCHAR(200),
+    occurred_at     DATETIME,
+    recorded_by     BIGINT UNSIGNED, -- 关联 account.id（记录人）
+    note            TEXT,
+    created_at      DATETIME                                                   NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_finance_item FOREIGN KEY (related_item_id) REFERENCES items (id) ON DELETE SET NULL,
+    CONSTRAINT fk_finance_user FOREIGN KEY (recorded_by) REFERENCES account (id) ON DELETE SET NULL,
+    INDEX (record_no)
+) ENGINE = InnoDB
+  DEFAULT CHARSET = utf8mb4 COMMENT ='财务相关记录';
+
+-- 邮件通知规则/历史
+DROP TABLE IF EXISTS email_notices;
+CREATE TABLE email_notices
+(
+    id            BIGINT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
+    name          VARCHAR(200),
+    target_emails TEXT,         -- 以逗号分隔或 JSON 数组
+    subject       VARCHAR(300),
+    body          TEXT,
+    enabled       TINYINT(1)      NOT NULL DEFAULT 1,
+    schedule_cron VARCHAR(100), -- 若使用定时任务
+    last_sent_at  DATETIME,
+    created_at    DATETIME        NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at    DATETIME        NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
+) ENGINE = InnoDB
+  DEFAULT CHARSET = utf8mb4 COMMENT ='邮件通知规则/历史';
+
+-- 附件表（文件存储路径）
+DROP TABLE IF EXISTS attachments;
+CREATE TABLE attachments
+(
+    id            BIGINT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
+    related_table VARCHAR(100),    -- 指示关联表，如 'items'
+    related_id    BIGINT UNSIGNED, -- 关联记录 ID
+    file_name     VARCHAR(300),
+    file_path     VARCHAR(1000),
+    file_size     BIGINT UNSIGNED,
+    content_type  VARCHAR(200),
+    uploaded_by   BIGINT UNSIGNED, -- 关联 account.id（上传者）
+    uploaded_at   DATETIME        NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_attachments_user FOREIGN KEY (uploaded_by) REFERENCES account (id) ON DELETE SET NULL,
+    INDEX (related_table, related_id)
+) ENGINE = InnoDB
+  DEFAULT CHARSET = utf8mb4 COMMENT ='文件附件存储索引表';

src/backend/.gitignore

@@ -5,6 +5,9 @@ build/
 !**/src/main/**/build/
 !**/src/test/**/build/
 
+src/main/resources/
+!src/main/resources/application.yaml
+
 ### STS ###
 .apt_generated
 .classpath

src/backend/build.gradle.kts

@@ -1,12 +1,13 @@
 plugins {
-    kotlin("jvm") version "2.2.21"
-    kotlin("plugin.spring") version "2.2.21"
-    id("org.springframework.boot") version "4.0.6"
+    kotlin("jvm") version "2.3.21"
+    kotlin("plugin.spring") version "2.3.21"
+    id("org.jetbrains.kotlin.plugin.serialization") version "2.4.20-RC"
+    id("org.springframework.boot") version "4.1.0"
     id("io.spring.dependency-management") version "1.1.7"
 }
 
 group = "club.itstudio"
-version = "0.0.1-SNAPSHOT"
+version = "1.0.0"
 description = "itmanager"
 
 java {
@@ -22,6 +23,7 @@ repositories {
 dependencies {
     implementation("com.auth0:java-jwt:4.4.0")
     implementation("com.baomidou:mybatis-plus-spring-boot4-starter:3.5.15")
+    implementation("com.baomidou:mybatis-plus-jsqlparser:3.5.15")
     implementation("org.springframework.boot:spring-boot-starter-amqp")
     implementation("org.springframework.boot:spring-boot-starter-data-redis-reactive")
     implementation("org.springframework.boot:spring-boot-starter-json")

src/backend/gradle.properties

@@ -0,0 +1,2 @@
+kotlin.jvm.target.validation=warning
+kotlin.jvm.target=25

src/backend/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,6 @@
+#Mon Aug 17 12:30:11 UTC 2026
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://mirrors.cloud.tencent.com/gradle/gradle-9.7.0-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

src/backend/gradlew

@@ -20,7 +20,7 @@
 
 ##############################################################################
 #
-#   Gradle start up script for POSIX generated by Gradle.
+#   gradlew start up script for POSIX generated by Gradle.
 #
 #   Important for running:
 #
@@ -29,7 +29,7 @@
 #       bash, then to run this script, type that shell name before the whole
 #       command line, like:
 #
-#           ksh Gradle
+#           ksh gradlew
 #
 #       Busybox and similar reduced shells will NOT work, because this script
 #       requires all of these POSIX shell features:

src/backend/gradlew.bat

@@ -19,7 +19,7 @@
 @if "%DEBUG%"=="" @echo off
 @rem ##########################################################################
 @rem
-@rem  Gradle startup script for Windows
+@rem  gradlew startup script for Windows
 @rem
 @rem ##########################################################################
 
@@ -72,7 +72,7 @@ echo location of your Java installation. 1>&2
 
 
 
-@rem Execute Gradle
+@rem Execute gradlew
 @rem endlocal doesn't take effect until after the line is parsed and variables are expanded
 @rem which allows us to clear the local environment before executing the java command
 endlocal & "%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -jar "%APP_HOME%\gradle\wrapper\gradle-wrapper.jar" %* & call :exitWithErrorLevel

src/backend/src/main/kotlin/club/itstudio/itmanager/config/MybatisConfig.kt

@@ -0,0 +1,18 @@
+package club.itstudio.itmanager.config
+
+import com.baomidou.mybatisplus.annotation.DbType
+import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor
+import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor
+import org.springframework.context.annotation.Bean
+import org.springframework.context.annotation.Configuration
+
+@Configuration
+class MybatisConfig {
+
+    @Bean
+    fun mybatisPlusInterceptor(): MybatisPlusInterceptor {
+        val interceptor = MybatisPlusInterceptor()
+        interceptor.addInnerInterceptor(PaginationInnerInterceptor(DbType.MARIADB))
+        return interceptor
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/config/SerializationConfig.kt

@@ -1,6 +1,9 @@
 package club.itstudio.itmanager.config
 
+import club.itstudio.itmanager.utils.BigDecimalSerializer
 import kotlinx.serialization.json.Json
+import kotlinx.serialization.modules.SerializersModule
+import kotlinx.serialization.modules.contextual
 import org.springframework.context.annotation.Bean
 import org.springframework.context.annotation.Configuration
 
@@ -9,6 +12,9 @@ class SerializationConfig {
 
     @Bean
     fun kotlinxSerializationJson(): Json = Json {
+        serializersModule = SerializersModule {
+            contextual(BigDecimalSerializer)
+        }
         ignoreUnknownKeys = true
         isLenient = true
         encodeDefaults = false

src/backend/src/main/kotlin/club/itstudio/itmanager/controller/v1/AuthorizeController.kt

@@ -1,21 +1,17 @@
 package club.itstudio.itmanager.controller.v1
 
 import club.itstudio.itmanager.entity.ApiResponse
+import club.itstudio.itmanager.entity.enums.EmailType
 import club.itstudio.itmanager.entity.vo.request.EmailRegisterVO
 import club.itstudio.itmanager.entity.vo.request.PasswordResetVO
-import club.itstudio.itmanager.service.AccountService
+import club.itstudio.itmanager.service.v1.AuthorizationService
+import club.itstudio.itmanager.utils.Const
 import jakarta.validation.Valid
 import jakarta.validation.constraints.Email
 import jakarta.validation.constraints.NotBlank
-import jakarta.validation.constraints.Pattern
 import org.slf4j.LoggerFactory
 import org.springframework.validation.annotation.Validated
-import org.springframework.web.bind.annotation.GetMapping
-import org.springframework.web.bind.annotation.PostMapping
-import org.springframework.web.bind.annotation.RequestBody
-import org.springframework.web.bind.annotation.RequestMapping
-import org.springframework.web.bind.annotation.RequestParam
-import org.springframework.web.bind.annotation.RestController
+import org.springframework.web.bind.annotation.*
 import org.springframework.web.server.ServerWebExchange
 import reactor.core.publisher.Mono
 
@@ -23,34 +19,34 @@ import reactor.core.publisher.Mono
 @RestController
 @RequestMapping("/api/v1/auth")
 class AuthorizeController(
-    private val service: AccountService
+    private val service: AuthorizationService
 ) {
     private val logger = LoggerFactory.getLogger(this::class.java)
 
     @GetMapping("/ask-code")
     fun askVerifyCode(
         @RequestParam @NotBlank @Email email: String,
-        @RequestParam @Pattern(regexp = "(register|reset)") type: String,
+        @RequestParam type: EmailType,
         exchange: ServerWebExchange
     ): Mono<ApiResponse<Any?>> {
         logger.info("Trying to ask code")
         val ip = exchange.request.remoteAddress?.address?.hostAddress ?: "unknown"
         return service.askEmailVerifyCode(type, email, ip)
-            .map { messageHandler(it) }
+            .map(Const::messageHandler)
     }
 
     @PostMapping("/register")
     fun emailRegister(@RequestBody @Valid vo: EmailRegisterVO): Mono<ApiResponse<Any?>> {
         logger.info("Trying to register")
         return service.registerEmailAccount(vo)
-            .map { messageHandler(it) }
+            .map(Const::messageHandler)
     }
 
     @PostMapping("/reset")
     fun emailResetPassword(@RequestBody @Valid vo: PasswordResetVO): Mono<ApiResponse<Any?>> {
         logger.info("Trying to reset password")
         return service.resetEmailAccountPassword(vo)
-            .map { messageHandler(it) }
+            .map(Const::messageHandler)
     }
 
     @GetMapping("/logout")
@@ -71,14 +67,6 @@ class AuthorizeController(
         return service
             .jwtTokenRelogin(authorization)
             ?.map { ApiResponse.success(it) }
-            ?: Mono.just(messageHandler("Please login with password."))
-    }
-
-    private fun messageHandler(wrongMessage: String): ApiResponse<Any?> {
-        return if (wrongMessage.isBlank()) {
-            ApiResponse.success()
-        } else {
-            ApiResponse.failure(400, null, wrongMessage)
-        }
+            ?: Mono.just(ApiResponse.failure(401, null, "Please login with password."))
     }
 }

src/backend/src/main/kotlin/club/itstudio/itmanager/controller/v1/EmailController.kt

@@ -0,0 +1,43 @@
+package club.itstudio.itmanager.controller.v1
+
+import club.itstudio.itmanager.entity.ApiResponse
+import club.itstudio.itmanager.entity.dto.EmailNotice
+import club.itstudio.itmanager.service.v1.EmailApiService
+import club.itstudio.itmanager.utils.Const
+import jakarta.validation.Valid
+import org.slf4j.LoggerFactory
+import org.springframework.validation.annotation.Validated
+import org.springframework.web.bind.annotation.*
+import reactor.core.publisher.Mono
+
+@Validated
+@RestController
+@RequestMapping("/api/v1/email")
+class EmailController(
+    private val service: EmailApiService
+) {
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    // notification-settings/ GET/POST 获取/更新通知设置和邮箱列表
+    @GetMapping("/notification-settings", "/notification-settings/")
+    fun getNotificationSettings(): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to list notification settings")
+        return service.getNotificationSettings()
+            .map { ApiResponse.success(it) }
+    }
+
+    @PostMapping("/notification-settings", "/notification-settings/")
+    fun updateNotificationSettings(@RequestBody @Valid notice: EmailNotice): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to update notification settings")
+        return service.updateNotificationSettings(notice)
+            .map(Const::messageHandler)
+    }
+
+    // toggle-email-status/ POST 切换邮箱启用/禁用状态
+    @PostMapping("/toggle-email-status", "/toggle-email-status/")
+    fun toggleEmailStatus(@RequestParam(required = false) id: Long?): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to toggle email status")
+        return service.toggleEmailStatus(id)
+            .map(Const::messageHandler)
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/controller/v1/FinanceController.kt

@@ -0,0 +1,111 @@
+package club.itstudio.itmanager.controller.v1
+
+import club.itstudio.itmanager.entity.ApiResponse
+import club.itstudio.itmanager.entity.dto.Category
+import club.itstudio.itmanager.entity.dto.FinanceRecord
+import club.itstudio.itmanager.service.v1.FinanceApiService
+import club.itstudio.itmanager.utils.Const
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page
+import jakarta.validation.Valid
+import org.slf4j.LoggerFactory
+import org.springframework.http.codec.multipart.FilePart
+import org.springframework.validation.annotation.Validated
+import org.springframework.web.bind.annotation.*
+import reactor.core.publisher.Flux
+import reactor.core.publisher.Mono
+
+@Validated
+@RestController
+@RequestMapping("/api/v1/finance")
+class FinanceController(
+    private val service: FinanceApiService
+) {
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    // finance/ GET/POST/PUT/DELETE 财务记录 CRUD 操作
+    @GetMapping("", "/")
+    fun getFinanceRecords(
+        @RequestParam(defaultValue = "1") pageNum: Long,
+        @RequestParam(defaultValue = "10") pageSize: Long,
+        @RequestParam(required = false) keyword: String?,
+        @RequestParam(required = false) type: String?,
+        @RequestParam(required = false) start: String?,
+        @RequestParam(required = false) end: String?,
+        @RequestParam(required = false) vendor: String?,
+        @RequestParam(required = false) itemId: Long?
+    ): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to list finance records")
+        val page = Page<FinanceRecord>(pageNum, pageSize)
+        return service.getFinanceRecords(page, keyword, type, start, end, vendor, itemId)
+            .map { ApiResponse.success(it) }
+    }
+
+    @PostMapping("", "/")
+    fun createFinanceRecord(@RequestBody @Valid record: FinanceRecord): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to create finance record")
+        return service.createFinanceRecord(record)
+            .map(Const::messageHandler)
+    }
+
+    @PutMapping("", "/")
+    fun updateFinanceRecord(@RequestBody @Valid record: FinanceRecord): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to update finance record")
+        return service.updateFinanceRecord(record)
+            .map(Const::messageHandler)
+    }
+
+    @DeleteMapping("", "/")
+    fun deleteFinanceRecord(@RequestParam(required = false) id: Long?): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to delete finance record")
+        return service.deleteFinanceRecord(id)
+            .map(Const::messageHandler)
+    }
+
+    // finance/{id}/upload_images/ POST 上传财务凭证图片
+    @PostMapping("/{id}/upload_images", "/{id}/upload_images/")
+    fun uploadImages(
+        @PathVariable("id") id: Long,
+        @RequestPart("files") files: Flux<FilePart>
+    ): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to upload images for finance record {}", id)
+        return service.uploadImages(id, files)
+            .map(Const::messageHandler)
+    }
+
+    // finance/{id}/ DELETE 删除财务记录（发送邮件通知）
+    @DeleteMapping("/{id}", "/{id}/")
+    fun deleteById(@PathVariable("id") id: Long): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to delete finance record {} with email notification", id)
+        return service.deleteById(id)
+            .map(Const::messageHandler)
+    }
+
+    // finance/categories/ GET/POST/PUT/DELETE 财务分类 CRUD 操作
+    @GetMapping("/categories", "/categories/")
+    fun getFinanceCategories(): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to list finance categories")
+        return service.getFinanceCategories()
+            .map { ApiResponse.success(it) }
+    }
+
+    @PostMapping("/categories", "/categories/")
+    fun createFinanceCategory(@RequestBody @Valid category: Category): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to create finance category")
+        return service.createFinanceCategory(category)
+            .map(Const::messageHandler)
+    }
+
+    @PutMapping("/categories", "/categories/")
+    fun updateFinanceCategory(@RequestBody @Valid category: Category): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to update finance category")
+        return service.updateFinanceCategory(category)
+            .map(Const::messageHandler)
+    }
+
+    @DeleteMapping("/categories", "/categories/")
+    fun deleteFinanceCategory(@RequestParam(required = false) id: Long?): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to delete finance category")
+        return service.deleteFinanceCategory(id)
+            .map(Const::messageHandler)
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/controller/v1/ItemsController.kt

@@ -0,0 +1,178 @@
+package club.itstudio.itmanager.controller.v1
+
+import club.itstudio.itmanager.entity.ApiResponse
+import club.itstudio.itmanager.entity.dto.Attachment
+import club.itstudio.itmanager.entity.dto.Category
+import club.itstudio.itmanager.entity.dto.Item
+import club.itstudio.itmanager.service.v1.ItemsApiService
+import club.itstudio.itmanager.utils.Const
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page
+import jakarta.validation.Valid
+import org.slf4j.LoggerFactory
+import org.springframework.http.codec.multipart.FilePart
+import org.springframework.validation.annotation.Validated
+import org.springframework.web.bind.annotation.*
+import reactor.core.publisher.Flux
+import reactor.core.publisher.Mono
+
+@Validated
+@RestController
+@RequestMapping("/api/v1/items")
+class ItemsController(
+    private val service: ItemsApiService
+) {
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    // items/ GET/POST/PUT/DELETE 物品 CRUD 操作
+    @GetMapping("", "/")
+    fun getItems(
+        @RequestParam(defaultValue = "1") pageNum: Long,
+        @RequestParam(defaultValue = "10") pageSize: Long,
+        @RequestParam(required = false) keyword: String?,
+        @RequestParam(required = false) status: String?
+    ): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to list items")
+        val page = Page<Item>(pageNum, pageSize)
+        return service.getItems(page, keyword, status)
+            .map { ApiResponse.success(it) }
+    }
+
+    @PostMapping("", "/")
+    fun createItem(@RequestBody @Valid item: Item): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to create item")
+        return service.createItem(item)
+            .map(Const::messageHandler)
+    }
+
+    @PutMapping("", "/")
+    fun updateItem(@RequestBody @Valid item: Item): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to update item")
+        return service.updateItem(item)
+            .map(Const::messageHandler)
+    }
+
+    @DeleteMapping("", "/")
+    fun deleteItem(@RequestParam(required = false) id: Long?): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to delete item")
+        return service.deleteItem(id)
+            .map(Const::messageHandler)
+    }
+
+    // items/{id}/upload_images/ POST 上传物品图片
+    @PostMapping("/{id}/upload_images", "/{id}/upload_images/")
+    fun uploadImages(
+        @PathVariable("id") id: Long,
+        @RequestPart("files") files: Flux<FilePart>
+    ): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to upload images for item {}", id)
+        return service.uploadImages(id, files)
+            .map(Const::messageHandler)
+    }
+
+    // items/{id}/set_primary_image/ POST 设置主图片
+    @PostMapping("/{id}/set_primary_image", "/{id}/set_primary_image/")
+    fun setPrimaryImage(
+        @PathVariable("id") id: Long,
+        @RequestParam imageId: Long
+    ): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to set primary image for item {}", id)
+        return service.setPrimaryImage(id, imageId)
+            .map(Const::messageHandler)
+    }
+
+    // items/{id}/borrow/ POST 借用物品
+    @PostMapping("/{id}/borrow", "/{id}/borrow/")
+    fun borrowItem(
+        @PathVariable("id") id: Long,
+        @RequestParam(defaultValue = "1") quantity: Int
+    ): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to borrow item {}", id)
+        return service.borrowItem(id, quantity)
+            .map(Const::messageHandler)
+    }
+
+    // items/{id}/return_item/ POST 归还物品
+    @PostMapping("/{id}/return_item", "/{id}/return_item/")
+    fun returnItem(
+        @PathVariable("id") id: Long,
+        @RequestParam(defaultValue = "1") quantity: Int
+    ): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to return item {}", id)
+        return service.returnItem(id, quantity)
+            .map(Const::messageHandler)
+    }
+
+    // items/available/ GET 获取可用物品列表
+    @GetMapping("/available", "/available/")
+    fun getAvailableItems(): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to list available items")
+        return service.getAvailableItems()
+            .map { ApiResponse.success(it) }
+    }
+
+    // items/in_use/ GET 获取使用中的物品列表
+    @GetMapping("/in_use", "/in_use/")
+    fun getInUseItems(): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to list in-use items")
+        return service.getInUseItems()
+            .map { ApiResponse.success(it) }
+    }
+
+    // items/categories/ GET/POST/PUT/DELETE 物品类别 CRUD 操作
+    @GetMapping("/categories", "/categories/")
+    fun getItemCategories(): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to list item categories")
+        return service.getItemCategories()
+            .map { ApiResponse.success(it) }
+    }
+
+    @PostMapping("/categories", "/categories/")
+    fun createItemCategory(@RequestBody @Valid category: Category): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to create item category")
+        return service.createItemCategory(category)
+            .map(Const::messageHandler)
+    }
+
+    @PutMapping("/categories", "/categories/")
+    fun updateItemCategory(@RequestBody @Valid category: Category): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to update item category")
+        return service.updateItemCategory(category)
+            .map(Const::messageHandler)
+    }
+
+    @DeleteMapping("/categories", "/categories/")
+    fun deleteItemCategory(@RequestParam(required = false) id: Long?): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to delete item category")
+        return service.deleteItemCategory(id)
+            .map(Const::messageHandler)
+    }
+
+    // items/images/ GET/POST/PUT/DELETE 物品图片 CRUD 操作
+    @GetMapping("/images", "/images/")
+    fun getItemImages(): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to list item images")
+        return service.getItemImages()
+            .map { ApiResponse.success(it) }
+    }
+
+    @PostMapping("/images", "/images/")
+    fun createItemImage(@RequestBody @Valid attachment: Attachment): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to create item image")
+        return service.createItemImage(attachment)
+            .map(Const::messageHandler)
+    }
+
+    @PutMapping("/images", "/images/")
+    fun updateItemImage(@RequestBody @Valid attachment: Attachment): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to update item image")
+        return service.updateItemImage(attachment)
+            .map(Const::messageHandler)
+    }
+
+    @DeleteMapping("/images", "/images/")
+    fun deleteItemImage(@RequestParam(required = false) id: Long?): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to delete item image")
+        return service.deleteItemImage(id)
+            .map(Const::messageHandler)
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/controller/v1/ProofImagesController.kt

@@ -0,0 +1,57 @@
+package club.itstudio.itmanager.controller.v1
+
+import club.itstudio.itmanager.entity.ApiResponse
+import club.itstudio.itmanager.entity.dto.Attachment
+import club.itstudio.itmanager.service.v1.ProofImagesApiService
+import club.itstudio.itmanager.utils.Const
+import jakarta.validation.Valid
+import org.slf4j.LoggerFactory
+import org.springframework.validation.annotation.Validated
+import org.springframework.web.bind.annotation.*
+import reactor.core.publisher.Mono
+
+@Validated
+@RestController
+@RequestMapping("/api/v1/proof-images")
+class ProofImagesController(
+    private val service: ProofImagesApiService
+) {
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    // proof-images/ GET/POST/PUT/DELETE 财务凭证图片 CRUD 操作
+    @GetMapping("", "/")
+    fun getProofImages(): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to list proof images")
+        return service.getProofImages()
+            .map { ApiResponse.success(it) }
+    }
+
+    @PostMapping("", "/")
+    fun createProofImage(@RequestBody @Valid attachment: Attachment): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to create proof image")
+        return service.createProofImage(attachment)
+            .map(Const::messageHandler)
+    }
+
+    @PutMapping("", "/")
+    fun updateProofImage(@RequestBody @Valid attachment: Attachment): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to update proof image")
+        return service.updateProofImage(attachment)
+            .map(Const::messageHandler)
+    }
+
+    @DeleteMapping("", "/")
+    fun deleteProofImage(@RequestParam(required = false) id: Long?): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to delete proof image")
+        return service.deleteProofImage(id)
+            .map(Const::messageHandler)
+    }
+
+    // proof-images/{id}/ DELETE 删除凭证图片（自动删除物理文件）
+    @DeleteMapping("/{id}", "/{id}/")
+    fun deleteById(@PathVariable("id") id: Long): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to delete proof image {}", id)
+        return service.deleteProofImage(id)
+            .map(Const::messageHandler)
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/controller/v1/UsagesController.kt

@@ -0,0 +1,115 @@
+package club.itstudio.itmanager.controller.v1
+
+import club.itstudio.itmanager.entity.ApiResponse
+import club.itstudio.itmanager.entity.dto.Attachment
+import club.itstudio.itmanager.entity.dto.BorrowRecord
+import club.itstudio.itmanager.service.v1.UsagesApiService
+import club.itstudio.itmanager.utils.Const
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page
+import jakarta.validation.Valid
+import org.slf4j.LoggerFactory
+import org.springframework.http.codec.multipart.FilePart
+import org.springframework.validation.annotation.Validated
+import org.springframework.web.bind.annotation.*
+import reactor.core.publisher.Flux
+import reactor.core.publisher.Mono
+
+@Validated
+@RestController
+@RequestMapping("/api/v1/usages")
+class UsagesController(
+    private val service: UsagesApiService
+) {
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    // usages/ GET/POST/PUT/DELETE 物品使用记录 CRUD 操作
+    @GetMapping("", "/")
+    fun getUsages(
+        @RequestParam(defaultValue = "1") pageNum: Long,
+        @RequestParam(defaultValue = "10") pageSize: Long,
+        @RequestParam(required = false) keyword: String?,
+        @RequestParam(required = false) status: String?
+    ): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to list usages")
+        val page = Page<BorrowRecord>(pageNum, pageSize)
+        return service.getUsages(page, keyword, status)
+            .map { ApiResponse.success(it) }
+    }
+
+    @PostMapping("", "/")
+    fun createUsage(@RequestBody @Valid record: BorrowRecord): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to create usage")
+        return service.createUsage(record)
+            .map(Const::messageHandler)
+    }
+
+    @PutMapping("", "/")
+    fun updateUsage(@RequestBody @Valid record: BorrowRecord): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to update usage")
+        return service.updateUsage(record)
+            .map(Const::messageHandler)
+    }
+
+    @DeleteMapping("", "/")
+    fun deleteUsage(@RequestParam(required = false) id: Long?): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to delete usage")
+        return service.deleteUsage(id)
+            .map(Const::messageHandler)
+    }
+
+    // usages/{id}/upload_images/ POST 上传使用记录图片
+    @PostMapping("/{id}/upload_images", "/{id}/upload_images/")
+    fun uploadImages(
+        @PathVariable("id") id: Long,
+        @RequestPart("files") files: Flux<FilePart>
+    ): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to upload images for usage {}", id)
+        return service.uploadImages(id, files)
+            .map(Const::messageHandler)
+    }
+
+    // usages/current/ GET 获取当前使用中的记录
+    @GetMapping("/current", "/current/")
+    fun getCurrentUsages(): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to list current usages")
+        return service.getCurrentUsages()
+            .map { ApiResponse.success(it) }
+    }
+
+    // usages/by_user/ GET 根据用户姓名获取使用记录
+    @GetMapping("/by_user", "/by_user/")
+    fun getUsagesByUser(@RequestParam(required = false) name: String?): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to list usages by user")
+        return service.getUsagesByUser(name)
+            .map { ApiResponse.success(it) }
+    }
+
+    // usages/images/ GET/POST/PUT/DELETE 使用记录图片 CRUD 操作
+    @GetMapping("/images", "/images/")
+    fun getUsageImages(): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to list usage images")
+        return service.getUsageImages()
+            .map { ApiResponse.success(it) }
+    }
+
+    @PostMapping("/images", "/images/")
+    fun createUsageImage(@RequestBody @Valid attachment: Attachment): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to create usage image")
+        return service.createUsageImage(attachment)
+            .map(Const::messageHandler)
+    }
+
+    @PutMapping("/images", "/images/")
+    fun updateUsageImage(@RequestBody @Valid attachment: Attachment): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to update usage image")
+        return service.updateUsageImage(attachment)
+            .map(Const::messageHandler)
+    }
+
+    @DeleteMapping("/images", "/images/")
+    fun deleteUsageImage(@RequestParam(required = false) id: Long?): Mono<ApiResponse<Any?>> {
+        logger.info("Trying to delete usage image")
+        return service.deleteUsageImage(id)
+            .map(Const::messageHandler)
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/DataCopy.kt

@@ -0,0 +1,46 @@
+package club.itstudio.itmanager.entity
+
+import kotlin.reflect.KClass
+import kotlin.reflect.KMutableProperty1
+import kotlin.reflect.KProperty1
+import kotlin.reflect.full.createInstance
+import kotlin.reflect.full.declaredMemberProperties
+import kotlin.reflect.full.memberProperties
+import kotlin.reflect.jvm.isAccessible
+import kotlin.reflect.jvm.javaField
+
+interface DataCopy {
+    fun <T : Any> toAnotherObject(
+        toClass: KClass<T>,
+        otherProperties: Map<String, Any?> = emptyMap()
+    ): T {
+        @Suppress("UNCHECKED_CAST")
+        val sourceProps = this::class.memberProperties
+            .associate { it.name to (it as KProperty1<Any, *>).get(this) }
+        return try {
+            val vo = toClass.createInstance()
+            for (prop in toClass.declaredMemberProperties) {
+                val value = when {
+                    sourceProps.containsKey(prop.name) -> sourceProps[prop.name]
+                    otherProperties.containsKey(prop.name) -> otherProperties[prop.name]
+                    else -> continue
+                }
+                @Suppress("UNCHECKED_CAST")
+                val mutableProp = prop as? KMutableProperty1<Any, Any?>
+                if (mutableProp != null) {
+                    mutableProp.isAccessible = true
+                    mutableProp.set(vo, value)
+                } else {
+                    val field = prop.javaField ?: continue
+                    field.isAccessible = true
+                    field.set(vo, value)
+                }
+            }
+            vo
+        } catch (e: ReflectiveOperationException) {
+            throw RuntimeException(
+                "Failed to instantiate ${toClass.simpleName}. Does it have a no-arg constructor?", e
+            )
+        }
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/dto/Account.kt

@@ -11,10 +11,13 @@ import kotlinx.serialization.Serializable
 @TableName("account")
 data class Account(
     @TableId(type = IdType.AUTO)
-    val id: Int? = null,
+    val id: Long? = null,
     val username: String = "",
     val password: String = "",
-    val email: String = "",
-    val role: String = "",
-    val registerTime: LocalDateTime? = null
+    val email: String? = null,
+    val fullName: String? = null,
+    val isActive: Boolean = true,
+    val isStaff: Boolean = false,
+    val createdAt: LocalDateTime? = null,
+    val updatedAt: LocalDateTime? = null
 ) : DataCopy

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/dto/Attachment.kt

@@ -0,0 +1,23 @@
+package club.itstudio.itmanager.entity.dto
+
+import com.baomidou.mybatisplus.annotation.IdType
+import com.baomidou.mybatisplus.annotation.TableId
+import com.baomidou.mybatisplus.annotation.TableName
+import club.itstudio.itmanager.entity.DataCopy
+import kotlinx.datetime.LocalDateTime
+import kotlinx.serialization.Serializable
+
+@Serializable
+@TableName("attachments")
+data class Attachment(
+    @TableId(type = IdType.AUTO)
+    val id: Long? = null,
+    val relatedTable: String? = null,
+    val relatedId: Long? = null,
+    val fileName: String? = null,
+    val filePath: String? = null,
+    val fileSize: Long? = null,
+    val contentType: String? = null,
+    val uploadedBy: Long? = null,
+    val uploadedAt: LocalDateTime? = null
+) : DataCopy

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/dto/BorrowRecord.kt

@@ -0,0 +1,26 @@
+package club.itstudio.itmanager.entity.dto
+
+import com.baomidou.mybatisplus.annotation.IdType
+import com.baomidou.mybatisplus.annotation.TableId
+import com.baomidou.mybatisplus.annotation.TableName
+import club.itstudio.itmanager.entity.DataCopy
+import kotlinx.datetime.LocalDateTime
+import kotlinx.serialization.Serializable
+
+@Serializable
+@TableName("borrow_records")
+data class BorrowRecord(
+    @TableId(type = IdType.AUTO)
+    val id: Long? = null,
+    val itemId: Long = 0,
+    val borrower: String = "",
+    val quantity: Int = 1,
+    val borrowDate: LocalDateTime? = null,
+    val dueDate: LocalDateTime? = null,
+    val returnDate: LocalDateTime? = null,
+    val status: String = "BORROWED",  // BORROWED / RETURNED / OVERDUE / CANCELED
+    val approver: String? = null,
+    val note: String? = null,
+    val createdAt: LocalDateTime? = null,
+    val updatedAt: LocalDateTime? = null
+) : DataCopy

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/dto/Category.kt

@@ -0,0 +1,20 @@
+package club.itstudio.itmanager.entity.dto
+
+import com.baomidou.mybatisplus.annotation.IdType
+import com.baomidou.mybatisplus.annotation.TableId
+import com.baomidou.mybatisplus.annotation.TableName
+import club.itstudio.itmanager.entity.DataCopy
+import kotlinx.datetime.LocalDateTime
+import kotlinx.serialization.Serializable
+
+@Serializable
+@TableName("categories")
+data class Category(
+    @TableId(type = IdType.AUTO)
+    val id: Long? = null,
+    val name: String = "",
+    val parentId: Long? = null,
+    val description: String? = null,
+    val createdAt: LocalDateTime? = null,
+    val updatedAt: LocalDateTime? = null
+) : DataCopy

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/dto/EmailNotice.kt

@@ -0,0 +1,24 @@
+package club.itstudio.itmanager.entity.dto
+
+import com.baomidou.mybatisplus.annotation.IdType
+import com.baomidou.mybatisplus.annotation.TableId
+import com.baomidou.mybatisplus.annotation.TableName
+import club.itstudio.itmanager.entity.DataCopy
+import kotlinx.datetime.LocalDateTime
+import kotlinx.serialization.Serializable
+
+@Serializable
+@TableName("email_notices")
+data class EmailNotice(
+    @TableId(type = IdType.AUTO)
+    val id: Long? = null,
+    val name: String? = null,
+    val targetEmails: String? = null,
+    val subject: String? = null,
+    val body: String? = null,
+    val enabled: Boolean = true,
+    val scheduleCron: String? = null,
+    val lastSentAt: LocalDateTime? = null,
+    val createdAt: LocalDateTime? = null,
+    val updatedAt: LocalDateTime? = null
+) : DataCopy

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/dto/EmailVerificationMsg.kt

@@ -1,10 +1,11 @@
 package club.itstudio.itmanager.entity.dto
 
+import club.itstudio.itmanager.entity.enums.EmailType
 import kotlinx.serialization.Serializable
 
 @Serializable
 data class EmailVerificationMsg(
     val email: String,
-    val type: String,
+    val type: EmailType,
     val code: String
 )

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/dto/FinanceRecord.kt

@@ -0,0 +1,28 @@
+package club.itstudio.itmanager.entity.dto
+
+import com.baomidou.mybatisplus.annotation.IdType
+import com.baomidou.mybatisplus.annotation.TableId
+import com.baomidou.mybatisplus.annotation.TableName
+import club.itstudio.itmanager.entity.DataCopy
+import club.itstudio.itmanager.entity.enums.FinanceRecordType
+import kotlinx.datetime.LocalDateTime
+import kotlinx.serialization.Contextual
+import kotlinx.serialization.Serializable
+import java.math.BigDecimal
+
+@Serializable
+@TableName("finance_records")
+data class FinanceRecord(
+    @TableId(type = IdType.AUTO)
+    val id: Long? = null,
+    val recordNo: String? = null,
+    val type: FinanceRecordType = FinanceRecordType.OTHER,
+    val relatedItemId: Long? = null,
+    val amount: @Contextual BigDecimal = BigDecimal.ZERO,
+    val currency: String = "CNY",
+    val vendor: String? = null,
+    val occurredAt: LocalDateTime? = null,
+    val recordedBy: Long? = null,
+    val note: String? = null,
+    val createdAt: LocalDateTime? = null
+) : DataCopy

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/dto/Item.kt

@@ -0,0 +1,36 @@
+package club.itstudio.itmanager.entity.dto
+
+import com.baomidou.mybatisplus.annotation.IdType
+import com.baomidou.mybatisplus.annotation.TableId
+import com.baomidou.mybatisplus.annotation.TableName
+import club.itstudio.itmanager.entity.DataCopy
+import kotlinx.datetime.LocalDate
+import kotlinx.datetime.LocalDateTime
+import kotlinx.serialization.Contextual
+import kotlinx.serialization.Serializable
+import java.math.BigDecimal
+
+@Serializable
+@TableName("items")
+data class Item(
+    @TableId(type = IdType.AUTO)
+    val id: Long? = null,
+    val code: String = "",
+    val name: String = "",
+    val categoryId: Long? = null,
+    val model: String? = null,
+    val brand: String? = null,
+    val location: String? = null,
+    val totalQuantity: Int = 0,
+    val availableQuantity: Int = 0,
+    val unit: String = "件",
+    val price: @Contextual BigDecimal? = null,
+    val purchaseDate: LocalDate? = null,
+    val supplier: String? = null,
+    val status: String = "normal",
+    val description: String? = null,
+    val imagePath: String? = null,
+    val createdBy: Long? = null,
+    val createdAt: LocalDateTime? = null,
+    val updatedAt: LocalDateTime? = null
+) : DataCopy

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/dto/ItemTransaction.kt

@@ -0,0 +1,25 @@
+package club.itstudio.itmanager.entity.dto
+
+import com.baomidou.mybatisplus.annotation.IdType
+import com.baomidou.mybatisplus.annotation.TableId
+import com.baomidou.mybatisplus.annotation.TableName
+import club.itstudio.itmanager.entity.DataCopy
+import club.itstudio.itmanager.entity.enums.TransactionType
+import kotlinx.datetime.LocalDateTime
+import kotlinx.serialization.Serializable
+
+@Serializable
+@TableName("item_transactions")
+data class ItemTransaction(
+    @TableId(type = IdType.AUTO)
+    val id: Long? = null,
+    val itemId: Long = 0,
+    val transType: TransactionType = TransactionType.IN,
+    val quantity: Int = 0,
+    val fromLocation: String? = null,
+    val toLocation: String? = null,
+    val relatedId: Long? = null,
+    val operatorId: Long? = null,
+    val note: String? = null,
+    val createdAt: LocalDateTime? = null
+) : DataCopy

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/enums/AccountRole.kt

@@ -0,0 +1,16 @@
+package club.itstudio.itmanager.entity.enums
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+@Serializable
+enum class AccountRole {
+    @SerialName("user")
+    USER,
+    @SerialName("admin")
+    ADMIN;
+
+    companion object {
+        fun fromIsStaff(isStaff: Boolean): AccountRole = if (isStaff) ADMIN else USER
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/enums/EmailType.kt

@@ -0,0 +1,16 @@
+package club.itstudio.itmanager.entity.enums
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+@Serializable
+enum class EmailType {
+    @SerialName("register")
+    REGISTER,
+    
+    @SerialName("reset")
+    RESET,
+    
+    @SerialName("finance-delete")
+    FINANCE_DELETE,
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/enums/FinanceRecordType.kt

@@ -0,0 +1,22 @@
+package club.itstudio.itmanager.entity.enums
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+@Serializable
+enum class FinanceRecordType {
+    @SerialName("PURCHASE")
+    PURCHASE,
+
+    @SerialName("REFUND")
+    REFUND,
+
+    @SerialName("REPAIR")
+    REPAIR,
+
+    @SerialName("DEPRECIATION")
+    DEPRECIATION,
+
+    @SerialName("OTHER")
+    OTHER,
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/enums/TransactionType.kt

@@ -0,0 +1,19 @@
+package club.itstudio.itmanager.entity.enums
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+@Serializable
+enum class TransactionType {
+    @SerialName("IN")
+    IN,
+
+    @SerialName("OUT")
+    OUT,
+
+    @SerialName("ADJUST")
+    ADJUST,
+
+    @SerialName("TRANSFER")
+    TRANSFER,
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/entity/vo/response/ReloginVO.kt

@@ -1,9 +1,11 @@
 package club.itstudio.itmanager.entity.vo.response
 
+import club.itstudio.itmanager.utils.DateUtils.getCurrentDateTime
+import kotlinx.datetime.LocalDateTime
 import kotlinx.serialization.Serializable
 
 @Serializable
 data class ReloginVO(
     val token: String = "",
-    val expire: String = "",
+    val expire: LocalDateTime = getCurrentDateTime(),
 )

src/backend/src/main/kotlin/club/itstudio/itmanager/listener/MailQueueListener.kt

@@ -1,6 +1,7 @@
 package club.itstudio.itmanager.listener
 
 import club.itstudio.itmanager.entity.dto.EmailVerificationMsg
+import club.itstudio.itmanager.entity.enums.EmailType
 import kotlinx.serialization.json.Json
 import org.slf4j.LoggerFactory
 import org.springframework.amqp.rabbit.annotation.RabbitHandler
@@ -28,21 +29,25 @@ class MailQueueListener(
         val (email, type, code) = data
         
         val message = when (type) {
-            "register" -> createMailMessage(
+            EmailType.REGISTER -> createMailMessage(
                 "Welcome to Our Service",
                 "Thank you for registering! Your verification code is: $code"
                         + "\nThis code is valid for 3 minutes.",
                 email
             )
 
-            "reset" -> createMailMessage(
+            EmailType.RESET -> createMailMessage(
                 "Password Reset Request",
                 "You requested a password reset. Your verification code is: $code"
                         + "\nThis code is valid for 3 minutes.",
                 email
             )
 
-            else -> return
+            EmailType.FINANCE_DELETE -> createMailMessage(
+                "Finance Record Deleted",
+                "A finance record has been deleted. Record No: $code",
+                email
+            )
         }
         sender.send(message)
         logger.info("Email sent to $email.")

src/backend/src/main/kotlin/club/itstudio/itmanager/mapper/AttachmentMapper.kt

@@ -0,0 +1,8 @@
+package club.itstudio.itmanager.mapper
+
+import com.baomidou.mybatisplus.core.mapper.BaseMapper
+import club.itstudio.itmanager.entity.dto.Attachment
+import org.apache.ibatis.annotations.Mapper
+
+@Mapper
+interface AttachmentMapper : BaseMapper<Attachment>

src/backend/src/main/kotlin/club/itstudio/itmanager/mapper/BorrowRecordMapper.kt

@@ -0,0 +1,8 @@
+package club.itstudio.itmanager.mapper
+
+import com.baomidou.mybatisplus.core.mapper.BaseMapper
+import club.itstudio.itmanager.entity.dto.BorrowRecord
+import org.apache.ibatis.annotations.Mapper
+
+@Mapper
+interface BorrowRecordMapper : BaseMapper<BorrowRecord>

src/backend/src/main/kotlin/club/itstudio/itmanager/mapper/CategoryMapper.kt

@@ -0,0 +1,8 @@
+package club.itstudio.itmanager.mapper
+
+import com.baomidou.mybatisplus.core.mapper.BaseMapper
+import club.itstudio.itmanager.entity.dto.Category
+import org.apache.ibatis.annotations.Mapper
+
+@Mapper
+interface CategoryMapper : BaseMapper<Category>

src/backend/src/main/kotlin/club/itstudio/itmanager/mapper/EmailNoticeMapper.kt

@@ -0,0 +1,8 @@
+package club.itstudio.itmanager.mapper
+
+import com.baomidou.mybatisplus.core.mapper.BaseMapper
+import club.itstudio.itmanager.entity.dto.EmailNotice
+import org.apache.ibatis.annotations.Mapper
+
+@Mapper
+interface EmailNoticeMapper : BaseMapper<EmailNotice>

src/backend/src/main/kotlin/club/itstudio/itmanager/mapper/FinanceRecordMapper.kt

@@ -0,0 +1,8 @@
+package club.itstudio.itmanager.mapper
+
+import com.baomidou.mybatisplus.core.mapper.BaseMapper
+import club.itstudio.itmanager.entity.dto.FinanceRecord
+import org.apache.ibatis.annotations.Mapper
+
+@Mapper
+interface FinanceRecordMapper : BaseMapper<FinanceRecord>

src/backend/src/main/kotlin/club/itstudio/itmanager/mapper/ItemMapper.kt

@@ -0,0 +1,8 @@
+package club.itstudio.itmanager.mapper
+
+import com.baomidou.mybatisplus.core.mapper.BaseMapper
+import club.itstudio.itmanager.entity.dto.Item
+import org.apache.ibatis.annotations.Mapper
+
+@Mapper
+interface ItemMapper : BaseMapper<Item>

src/backend/src/main/kotlin/club/itstudio/itmanager/mapper/ItemTransactionMapper.kt

@@ -0,0 +1,8 @@
+package club.itstudio.itmanager.mapper
+
+import com.baomidou.mybatisplus.core.mapper.BaseMapper
+import club.itstudio.itmanager.entity.dto.ItemTransaction
+import org.apache.ibatis.annotations.Mapper
+
+@Mapper
+interface ItemTransactionMapper : BaseMapper<ItemTransaction>

src/backend/src/main/kotlin/club/itstudio/itmanager/mapper/typehandler/TimeTypeHandler.kt

@@ -0,0 +1,49 @@
+package club.itstudio.itmanager.mapper.typehandler
+
+import kotlinx.datetime.LocalDateTime
+import kotlinx.datetime.toJavaLocalDateTime
+import kotlinx.datetime.toKotlinLocalDateTime
+import org.apache.ibatis.type.BaseTypeHandler
+import org.apache.ibatis.type.JdbcType
+import org.apache.ibatis.type.MappedJdbcTypes
+import org.apache.ibatis.type.MappedTypes
+import java.sql.CallableStatement
+import java.sql.PreparedStatement
+import java.sql.ResultSet
+
+@MappedTypes(LocalDateTime::class)
+@MappedJdbcTypes(JdbcType.TIMESTAMP)
+class TimeTypeHandler : BaseTypeHandler<LocalDateTime>() {
+    override fun setNonNullParameter(
+        ps: PreparedStatement,
+        i: Int,
+        parameter: LocalDateTime,
+        jdbcType: JdbcType?
+    ) {
+        ps.setObject(i, parameter.toJavaLocalDateTime())
+    }
+
+    override fun getNullableResult(
+        rs: ResultSet,
+        columnName: String
+    ): LocalDateTime? =
+        rs.getTimestamp(columnName)
+            ?.toLocalDateTime()
+            ?.toKotlinLocalDateTime()
+
+    override fun getNullableResult(
+        rs: ResultSet,
+        columnIndex: Int
+    ): LocalDateTime? =
+        rs.getTimestamp(columnIndex)
+            ?.toLocalDateTime()
+            ?.toKotlinLocalDateTime()
+
+    override fun getNullableResult(
+        cs: CallableStatement,
+        columnIndex: Int
+    ): LocalDateTime? =
+        cs.getTimestamp(columnIndex)
+            ?.toLocalDateTime()
+            ?.toKotlinLocalDateTime()
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/AccountService.kt

@@ -0,0 +1,21 @@
+package club.itstudio.itmanager.service
+
+import club.itstudio.itmanager.entity.dto.Account
+import com.baomidou.mybatisplus.extension.service.IService
+import org.springframework.security.core.userdetails.ReactiveUserDetailsService
+import reactor.core.publisher.Mono
+
+interface AccountService : IService<Account>, ReactiveUserDetailsService {
+    fun findAccountById(id: Long): Mono<Account>
+    fun findAccountByNameOrEmail(text: String): Mono<Account>
+    fun findAccountByName(username: String): Mono<Account>
+    fun findAccountByEmail(email: String): Mono<Account>
+    fun existAccountByName(username: String): Mono<Boolean>
+    fun existAccountByEmail(email: String): Mono<Boolean>
+    fun resetPasswordByEmail(email: String, encodedPassword: String): Mono<Void>
+    fun createAccount(account: Account): Mono<Boolean>
+
+//    fun batchInsert(accounts: List<Account>): Mono<Boolean>
+//    fun replaceAll(accounts: List<Account>): Mono<Boolean>
+//    fun exportAll(): Mono<List<Account>>
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/AttachmentService.kt

@@ -0,0 +1,16 @@
+package club.itstudio.itmanager.service
+
+import com.baomidou.mybatisplus.extension.service.IService
+import club.itstudio.itmanager.entity.dto.Attachment
+import reactor.core.publisher.Mono
+
+interface AttachmentService : IService<Attachment> {
+    fun getAttachmentById(id: Long): Mono<Attachment>
+    fun listByRelated(relatedTable: String, relatedId: Long): Mono<List<Attachment>>
+    fun listByUploader(uploadedBy: Long): Mono<List<Attachment>>
+    fun createAttachment(attachment: Attachment): Mono<Boolean>
+    fun updateAttachment(attachment: Attachment): Mono<Boolean>
+    fun deleteAttachment(id: Long): Mono<Boolean>
+    fun deleteByRelated(relatedTable: String, relatedId: Long): Mono<Boolean>
+    fun exportAllAttachments(): Mono<List<Attachment>>
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/BorrowRecordService.kt

@@ -0,0 +1,19 @@
+package club.itstudio.itmanager.service
+
+import com.baomidou.mybatisplus.extension.service.IService
+import club.itstudio.itmanager.entity.dto.BorrowRecord
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page
+import reactor.core.publisher.Mono
+
+interface BorrowRecordService : IService<BorrowRecord> {
+    fun getBorrowRecordById(id: Long): Mono<BorrowRecord>
+    fun pageUsages(page: Page<BorrowRecord>, keyword: String?, status: String?): Mono<Page<BorrowRecord>>
+    fun listByItem(itemId: Long): Mono<List<BorrowRecord>>
+    fun listByBorrower(borrower: String): Mono<List<BorrowRecord>>
+    fun listByStatus(status: String): Mono<List<BorrowRecord>>
+    fun listOverdueRecords(): Mono<List<BorrowRecord>>
+    fun createBorrowRecord(record: BorrowRecord): Mono<Boolean>
+    fun updateBorrowRecord(record: BorrowRecord): Mono<Boolean>
+    fun deleteBorrowRecord(id: Long): Mono<Boolean>
+    fun exportAllBorrowRecords(): Mono<List<BorrowRecord>>
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/CategoryService.kt

@@ -0,0 +1,15 @@
+package club.itstudio.itmanager.service
+
+import com.baomidou.mybatisplus.extension.service.IService
+import club.itstudio.itmanager.entity.dto.Category
+import reactor.core.publisher.Mono
+
+interface CategoryService : IService<Category> {
+    fun getCategoryById(id: Long): Mono<Category>
+    fun listAllCategories(): Mono<List<Category>>
+    fun listByParentId(parentId: Long): Mono<List<Category>>
+    fun createCategory(category: Category): Mono<Boolean>
+    fun updateCategory(category: Category): Mono<Boolean>
+    fun deleteCategory(id: Long): Mono<Boolean>
+    fun exportAllCategories(): Mono<List<Category>>
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/EmailNoticeService.kt

@@ -0,0 +1,16 @@
+package club.itstudio.itmanager.service
+
+import com.baomidou.mybatisplus.extension.service.IService
+import club.itstudio.itmanager.entity.dto.EmailNotice
+import reactor.core.publisher.Mono
+
+interface EmailNoticeService : IService<EmailNotice> {
+    fun getEmailNoticeById(id: Long): Mono<EmailNotice>
+    fun listAllNotices(): Mono<List<EmailNotice>>
+    fun listEnabledNotices(): Mono<List<EmailNotice>>
+    fun createEmailNotice(notice: EmailNotice): Mono<Boolean>
+    fun updateEmailNotice(notice: EmailNotice): Mono<Boolean>
+    fun deleteEmailNotice(id: Long): Mono<Boolean>
+    fun toggleEnabled(id: Long): Mono<Boolean>
+    fun exportAllEmailNotices(): Mono<List<EmailNotice>>
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/FileStorageService.kt

@@ -0,0 +1,61 @@
+package club.itstudio.itmanager.service
+
+import club.itstudio.itmanager.utils.Const
+import org.slf4j.LoggerFactory
+import org.springframework.beans.factory.annotation.Value
+import org.springframework.http.codec.multipart.FilePart
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Mono
+import reactor.core.scheduler.Schedulers
+import java.io.IOException
+import java.nio.file.Files
+import java.nio.file.Path
+import java.nio.file.Paths
+import java.util.*
+
+@Service
+class FileStorageService(
+    @Value($$"${app.file.data-path}")
+    private val dataPath: String
+) {
+    data class StoredFile(
+        val path: Path,
+        val size: Long
+    )
+
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    fun saveImage(file: FilePart, subDir: String, entityId: Long): Mono<StoredFile> {
+        val directory = Paths.get(dataPath, Const.FILE_DIR_IMAGE, subDir, entityId.toString())
+        val savedName = generateSafeFileName(file.filename())
+        val target = directory.resolve(savedName)
+        return Mono.fromCallable<Void> { Files.createDirectories(directory); null }
+            .then(file.transferTo(target))
+            .then(Mono.fromCallable { StoredFile(target, Files.size(target)) })
+            .subscribeOn(Schedulers.boundedElastic())
+    }
+
+    fun deleteFile(path: String?): Mono<Void> {
+        if (path.isNullOrBlank()) return Mono.empty()
+        return Mono.fromRunnable<Void> {
+            try {
+                Files.deleteIfExists(Paths.get(path))
+            } catch (e: IOException) {
+                logger.warn("Failed to delete file: {}", path, e)
+            }
+        }.subscribeOn(Schedulers.boundedElastic())
+    }
+
+    fun generateSafeFileName(original: String?): String {
+        val extension = original
+            ?.substringAfterLast('.')
+            ?.lowercase()
+            ?.takeIf {
+                it.isNotBlank() &&
+                        it.length <= 10 &&
+                        it.all { ch -> ch.isLetterOrDigit() }
+            }
+        return if (extension != null) "${UUID.randomUUID()}.$extension" else UUID.randomUUID().toString()
+    }
+}
+

src/backend/src/main/kotlin/club/itstudio/itmanager/service/FinanceRecordService.kt

@@ -0,0 +1,27 @@
+package club.itstudio.itmanager.service
+
+import com.baomidou.mybatisplus.extension.service.IService
+import club.itstudio.itmanager.entity.dto.FinanceRecord
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page
+import reactor.core.publisher.Mono
+
+interface FinanceRecordService : IService<FinanceRecord> {
+    fun getFinanceRecordById(id: Long): Mono<FinanceRecord>
+    fun pageFinanceRecords(
+        page: Page<FinanceRecord>,
+        keyword: String?,
+        type: String?,
+        start: String?,
+        end: String?,
+        vendor: String?,
+        itemId: Long?
+    ): Mono<Page<FinanceRecord>>
+    fun listByType(type: String): Mono<List<FinanceRecord>>
+    fun listByDateRange(start: String, end: String): Mono<List<FinanceRecord>>
+    fun listByVendor(vendor: String): Mono<List<FinanceRecord>>
+    fun listByRelatedItem(itemId: Long): Mono<List<FinanceRecord>>
+    fun createFinanceRecord(record: FinanceRecord): Mono<Boolean>
+    fun updateFinanceRecord(record: FinanceRecord): Mono<Boolean>
+    fun deleteFinanceRecord(id: Long): Mono<Boolean>
+    fun exportAllFinanceRecords(): Mono<List<FinanceRecord>>
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/ItemService.kt

@@ -0,0 +1,23 @@
+package club.itstudio.itmanager.service
+
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page
+import com.baomidou.mybatisplus.extension.service.IService
+import club.itstudio.itmanager.entity.dto.Item
+import reactor.core.publisher.Mono
+
+interface ItemService : IService<Item> {
+    fun pageItems(page: Page<Item>, keyword: String?, status: String?): Mono<Page<Item>>
+    fun getItemById(id: Long): Mono<Item>
+    fun listAvailableItems(): Mono<List<Item>>
+    fun listInUseItems(): Mono<List<Item>>
+    fun listItemsByCategory(categoryId: Long): Mono<List<Item>>
+    fun createItem(item: Item): Mono<Boolean>
+    fun updateItem(item: Item): Mono<Boolean>
+    fun removeItemById(id: Long): Mono<Boolean>
+    fun setPrimaryImage(id: Long, imagePath: String): Mono<Boolean>
+    fun borrowItem(id: Long, quantity: Int): Mono<Boolean>
+    fun returnItem(id: Long, quantity: Int): Mono<Boolean>
+    fun batchInsertItems(items: List<Item>): Mono<Boolean>
+    fun replaceAllItems(items: List<Item>): Mono<Boolean>
+    fun exportAllItems(): Mono<List<Item>>
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/ItemTransactionService.kt

@@ -0,0 +1,16 @@
+package club.itstudio.itmanager.service
+
+import com.baomidou.mybatisplus.extension.service.IService
+import club.itstudio.itmanager.entity.dto.ItemTransaction
+import reactor.core.publisher.Mono
+
+interface ItemTransactionService : IService<ItemTransaction> {
+    fun getTransactionById(id: Long): Mono<ItemTransaction>
+    fun listByItem(itemId: Long): Mono<List<ItemTransaction>>
+    fun listByType(transType: String): Mono<List<ItemTransaction>>
+    fun listByOperator(operatorId: Long): Mono<List<ItemTransaction>>
+    fun createTransaction(transaction: ItemTransaction): Mono<Boolean>
+    fun updateTransaction(transaction: ItemTransaction): Mono<Boolean>
+    fun deleteTransaction(id: Long): Mono<Boolean>
+    fun exportAllTransactions(): Mono<List<ItemTransaction>>
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/impl/AccountServiceImpl.kt

@@ -0,0 +1,158 @@
+package club.itstudio.itmanager.service.impl
+
+import club.itstudio.itmanager.entity.dto.Account
+import club.itstudio.itmanager.entity.enums.AccountRole
+import club.itstudio.itmanager.mapper.AccountMapper
+import club.itstudio.itmanager.service.AccountService
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl
+import org.slf4j.LoggerFactory
+import org.springframework.security.core.userdetails.User
+import org.springframework.security.core.userdetails.UserDetails
+import org.springframework.security.core.userdetails.UsernameNotFoundException
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Mono
+import reactor.core.scheduler.Schedulers
+import javax.security.auth.login.AccountNotFoundException
+import kotlin.jvm.java
+
+@Service
+class AccountServiceImpl : ServiceImpl<AccountMapper, Account>(), AccountService {
+
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    override fun findByUsername(
+        username: String
+    ): Mono<UserDetails> {
+
+        return findAccountByName(username)
+            .map {
+                User.withUsername(it.username)
+                    .password(it.password)
+                    .roles(AccountRole.fromIsStaff(it.isStaff).name)
+                    .build()
+            }
+            .onErrorMap(
+                AccountNotFoundException::class.java
+            ) {
+                UsernameNotFoundException(
+                    "User not found"
+                )
+            }
+    }
+
+    override fun findAccountByName(username: String): Mono<Account> =
+        findAccount("username") {
+            ktQuery()
+                .eq(Account::username, username)
+                .one()
+        }
+
+    override fun findAccountById(id: Long): Mono<Account> =
+        blockingCall {
+            logger.info("Searching account by id")
+            ktQuery()
+                .eq(Account::id, id)
+                .one()
+        }
+
+    override fun findAccountByEmail(email: String): Mono<Account> =
+        findAccount("email") {
+            ktQuery()
+                .eq(Account::email, email)
+                .one()
+        }
+
+    private fun <T : Any> blockingCall(
+        block: () -> T?
+    ): Mono<T> =
+        Mono.fromCallable(block)
+            .subscribeOn(Schedulers.boundedElastic())
+
+    private fun findAccount(
+        fieldName: String,
+        query: () -> Account?
+    ): Mono<Account> {
+        return blockingCall {
+            logger.info(
+                "Searching account by {}",
+                fieldName
+            )
+            query()
+        }.switchIfEmpty(
+            Mono.error(
+                AccountNotFoundException()
+            )
+        )
+    }
+
+    override fun findAccountByNameOrEmail(
+        text: String
+    ): Mono<Account> {
+        return blockingCall {
+            logger.info(
+                "Searching account by identifier"
+            )
+            ktQuery()
+                .and {
+                    it.eq(Account::email, text)
+                        .or()
+                        .eq(Account::username, text)
+                }
+                .one()
+        }.switchIfEmpty(
+            Mono.error(AccountNotFoundException())
+        )
+    }
+
+    override fun existAccountByName(
+        username: String
+    ): Mono<Boolean> {
+        return blockingCall {
+            ktQuery()
+                .eq(Account::username, username)
+                .exists()
+
+        }
+    }
+
+    override fun existAccountByEmail(
+        email: String
+    ): Mono<Boolean> {
+        return blockingCall {
+            ktQuery()
+                .eq(Account::email, email)
+                .exists()
+
+        }
+    }
+
+    override fun resetPasswordByEmail(
+        email: String,
+        encodedPassword: String
+    ): Mono<Void> {
+        return blockingCall {
+            ktUpdate()
+                .eq(Account::email, email)
+                .set(
+                    Account::password,
+                    encodedPassword
+                )
+                .update()
+        }
+            .flatMap { updated ->
+                if (updated) {
+                    Mono.empty()
+                } else {
+                    Mono.error(
+                        AccountNotFoundException()
+                    )
+                }
+            }
+    }
+
+    override fun createAccount(account: Account): Mono<Boolean> =
+        blockingCall {
+            logger.info("Creating account")
+            save(account)
+        }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/impl/AttachmentServiceImpl.kt

@@ -0,0 +1,78 @@
+package club.itstudio.itmanager.service.impl
+
+import club.itstudio.itmanager.entity.dto.Attachment
+import club.itstudio.itmanager.mapper.AttachmentMapper
+import club.itstudio.itmanager.service.AttachmentService
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl
+import org.slf4j.LoggerFactory
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Mono
+import reactor.core.scheduler.Schedulers
+
+@Service
+class AttachmentServiceImpl : ServiceImpl<AttachmentMapper, Attachment>(), AttachmentService {
+
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    private fun <T : Any> blockingCall(block: () -> T?): Mono<T> =
+        Mono.fromCallable(block).subscribeOn(Schedulers.boundedElastic())
+
+    override fun getAttachmentById(id: Long): Mono<Attachment> =
+        blockingCall {
+            logger.info("Searching attachment by id")
+            ktQuery()
+                .eq(Attachment::id, id)
+                .one()
+        }.switchIfEmpty(Mono.error(NoSuchElementException("Attachment not found")))
+
+    override fun listByRelated(relatedTable: String, relatedId: Long): Mono<List<Attachment>> =
+        blockingCall {
+            logger.info("Searching attachments by related table and id")
+            ktQuery()
+                .eq(Attachment::relatedTable, relatedTable)
+                .eq(Attachment::relatedId, relatedId)
+                .list()
+        }
+
+    override fun listByUploader(uploadedBy: Long): Mono<List<Attachment>> =
+        blockingCall {
+            logger.info("Searching attachments by uploader")
+            ktQuery()
+                .eq(Attachment::uploadedBy, uploadedBy)
+                .list()
+        }
+
+    override fun createAttachment(attachment: Attachment): Mono<Boolean> =
+        blockingCall {
+            logger.info("Creating attachment")
+            save(attachment)
+        }
+
+    override fun updateAttachment(attachment: Attachment): Mono<Boolean> =
+        blockingCall {
+            logger.info("Updating attachment")
+            updateById(attachment)
+        }
+
+    override fun deleteAttachment(id: Long): Mono<Boolean> =
+        blockingCall {
+            logger.info("Deleting attachment by id")
+            removeById(id)
+        }
+
+    override fun deleteByRelated(relatedTable: String, relatedId: Long): Mono<Boolean> =
+        blockingCall {
+            logger.info("Deleting attachments by related table and id")
+            remove(
+                ktQuery()
+                    .eq(Attachment::relatedTable, relatedTable)
+                    .eq(Attachment::relatedId, relatedId)
+            )
+        }
+
+    override fun exportAllAttachments(): Mono<List<Attachment>> =
+        blockingCall {
+            logger.info("Exporting all attachments")
+            list()
+        }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/impl/BorrowRecordServiceImpl.kt

@@ -0,0 +1,109 @@
+package club.itstudio.itmanager.service.impl
+
+import club.itstudio.itmanager.entity.dto.BorrowRecord
+import club.itstudio.itmanager.mapper.BorrowRecordMapper
+import club.itstudio.itmanager.service.BorrowRecordService
+import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper
+import com.baomidou.mybatisplus.core.metadata.OrderItem
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl
+import org.slf4j.LoggerFactory
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Mono
+import reactor.core.scheduler.Schedulers
+
+@Service
+class BorrowRecordServiceImpl : ServiceImpl<BorrowRecordMapper, BorrowRecord>(), BorrowRecordService {
+
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    private fun <T : Any> blockingCall(block: () -> T?): Mono<T> =
+        Mono.fromCallable(block).subscribeOn(Schedulers.boundedElastic())
+
+    override fun getBorrowRecordById(id: Long): Mono<BorrowRecord> =
+        blockingCall {
+            logger.info("Searching borrow record by id")
+            ktQuery()
+                .eq(BorrowRecord::id, id)
+                .one()
+        }.switchIfEmpty(Mono.error(NoSuchElementException("BorrowRecord not found")))
+
+    override fun pageUsages(
+        page: Page<BorrowRecord>,
+        keyword: String?,
+        status: String?
+    ): Mono<Page<BorrowRecord>> =
+        blockingCall {
+            logger.info("Paging borrow records")
+            if (keyword.isNullOrBlank() && status.isNullOrBlank()) {
+                page.addOrder(OrderItem.desc("created_at"))
+                page(page)
+            } else {
+                val wrapper = QueryWrapper<BorrowRecord>()
+                if (!keyword.isNullOrBlank()) {
+                    wrapper.like("borrower", keyword)
+                }
+                if (!status.isNullOrBlank()) {
+                    wrapper.eq("status", status)
+                }
+                wrapper.orderByDesc("created_at")
+                page(page, wrapper)
+            }
+        }
+
+    override fun listByItem(itemId: Long): Mono<List<BorrowRecord>> =
+        blockingCall {
+            logger.info("Searching borrow records by item id")
+            ktQuery()
+                .eq(BorrowRecord::itemId, itemId)
+                .list()
+        }
+
+    override fun listByBorrower(borrower: String): Mono<List<BorrowRecord>> =
+        blockingCall {
+            logger.info("Searching borrow records by borrower")
+            ktQuery()
+                .eq(BorrowRecord::borrower, borrower)
+                .list()
+        }
+
+    override fun listByStatus(status: String): Mono<List<BorrowRecord>> =
+        blockingCall {
+            logger.info("Searching borrow records by status")
+            ktQuery()
+                .eq(BorrowRecord::status, status)
+                .list()
+        }
+
+    override fun listOverdueRecords(): Mono<List<BorrowRecord>> =
+        blockingCall {
+            logger.info("Searching overdue borrow records")
+            ktQuery()
+                .eq(BorrowRecord::status, "OVERDUE")
+                .list()
+        }
+
+    override fun createBorrowRecord(record: BorrowRecord): Mono<Boolean> =
+        blockingCall {
+            logger.info("Creating borrow record")
+            save(record)
+        }
+
+    override fun updateBorrowRecord(record: BorrowRecord): Mono<Boolean> =
+        blockingCall {
+            logger.info("Updating borrow record")
+            updateById(record)
+        }
+
+    override fun deleteBorrowRecord(id: Long): Mono<Boolean> =
+        blockingCall {
+            logger.info("Deleting borrow record by id")
+            removeById(id)
+        }
+
+    override fun exportAllBorrowRecords(): Mono<List<BorrowRecord>> =
+        blockingCall {
+            logger.info("Exporting all borrow records")
+            list()
+        }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/impl/CategoryServiceImpl.kt

@@ -0,0 +1,65 @@
+package club.itstudio.itmanager.service.impl
+
+import club.itstudio.itmanager.entity.dto.Category
+import club.itstudio.itmanager.mapper.CategoryMapper
+import club.itstudio.itmanager.service.CategoryService
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl
+import org.slf4j.LoggerFactory
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Mono
+import reactor.core.scheduler.Schedulers
+
+@Service
+class CategoryServiceImpl : ServiceImpl<CategoryMapper, Category>(), CategoryService {
+
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    private fun <T : Any> blockingCall(block: () -> T?): Mono<T> =
+        Mono.fromCallable(block).subscribeOn(Schedulers.boundedElastic())
+
+    override fun getCategoryById(id: Long): Mono<Category> =
+        blockingCall {
+            logger.info("Searching category by id")
+            ktQuery()
+                .eq(Category::id, id)
+                .one()
+        }.switchIfEmpty(Mono.error(NoSuchElementException("Category not found")))
+
+    override fun listAllCategories(): Mono<List<Category>> =
+        blockingCall {
+            logger.info("Listing all categories")
+            list()
+        }
+
+    override fun listByParentId(parentId: Long): Mono<List<Category>> =
+        blockingCall {
+            logger.info("Searching categories by parent id")
+            ktQuery()
+                .eq(Category::parentId, parentId)
+                .list()
+        }
+
+    override fun createCategory(category: Category): Mono<Boolean> =
+        blockingCall {
+            logger.info("Creating category")
+            save(category)
+        }
+
+    override fun updateCategory(category: Category): Mono<Boolean> =
+        blockingCall {
+            logger.info("Updating category")
+            updateById(category)
+        }
+
+    override fun deleteCategory(id: Long): Mono<Boolean> =
+        blockingCall {
+            logger.info("Deleting category by id")
+            removeById(id)
+        }
+
+    override fun exportAllCategories(): Mono<List<Category>> =
+        blockingCall {
+            logger.info("Exporting all categories")
+            list()
+        }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/impl/EmailNoticeServiceImpl.kt

@@ -0,0 +1,72 @@
+package club.itstudio.itmanager.service.impl
+
+import club.itstudio.itmanager.entity.dto.EmailNotice
+import club.itstudio.itmanager.mapper.EmailNoticeMapper
+import club.itstudio.itmanager.service.EmailNoticeService
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl
+import org.slf4j.LoggerFactory
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Mono
+import reactor.core.scheduler.Schedulers
+
+@Service
+class EmailNoticeServiceImpl : ServiceImpl<EmailNoticeMapper, EmailNotice>(), EmailNoticeService {
+
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    private fun <T : Any> blockingCall(block: () -> T?): Mono<T> =
+        Mono.fromCallable(block).subscribeOn(Schedulers.boundedElastic())
+
+    override fun getEmailNoticeById(id: Long): Mono<EmailNotice> =
+        blockingCall {
+            logger.info("Searching email notice by id")
+            ktQuery()
+                .eq(EmailNotice::id, id)
+                .one()
+        }.switchIfEmpty(Mono.error(NoSuchElementException("EmailNotice not found")))
+
+    override fun listAllNotices(): Mono<List<EmailNotice>> =
+        blockingCall {
+            logger.info("Listing all email notices")
+            list()
+        }
+
+    override fun listEnabledNotices(): Mono<List<EmailNotice>> =
+        blockingCall {
+            logger.info("Listing enabled email notices")
+            ktQuery()
+                .eq(EmailNotice::enabled, true)
+                .list()
+        }
+
+    override fun createEmailNotice(notice: EmailNotice): Mono<Boolean> =
+        blockingCall {
+            logger.info("Creating email notice")
+            save(notice)
+        }
+
+    override fun updateEmailNotice(notice: EmailNotice): Mono<Boolean> =
+        blockingCall {
+            logger.info("Updating email notice")
+            updateById(notice)
+        }
+
+    override fun deleteEmailNotice(id: Long): Mono<Boolean> =
+        blockingCall {
+            logger.info("Deleting email notice by id")
+            removeById(id)
+        }
+
+    override fun toggleEnabled(id: Long): Mono<Boolean> =
+        blockingCall {
+            val notice = ktQuery().eq(EmailNotice::id, id).one()
+            notice != null
+                    && updateById(notice.copy(enabled = !notice.enabled))
+        }
+
+    override fun exportAllEmailNotices(): Mono<List<EmailNotice>> =
+        blockingCall {
+            logger.info("Exporting all email notices")
+            list()
+        }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/impl/FinanceRecordServiceImpl.kt

@@ -0,0 +1,129 @@
+package club.itstudio.itmanager.service.impl
+
+import club.itstudio.itmanager.entity.dto.FinanceRecord
+import club.itstudio.itmanager.mapper.FinanceRecordMapper
+import club.itstudio.itmanager.service.FinanceRecordService
+import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl
+import org.slf4j.LoggerFactory
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Mono
+import reactor.core.scheduler.Schedulers
+
+@Service
+class FinanceRecordServiceImpl : ServiceImpl<FinanceRecordMapper, FinanceRecord>(), FinanceRecordService {
+
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    private fun <T : Any> blockingCall(block: () -> T?): Mono<T> =
+        Mono.fromCallable(block).subscribeOn(Schedulers.boundedElastic())
+
+    override fun getFinanceRecordById(id: Long): Mono<FinanceRecord> =
+        blockingCall {
+            logger.info("Searching finance record by id")
+            ktQuery()
+                .eq(FinanceRecord::id, id)
+                .one()
+        }.switchIfEmpty(Mono.error(NoSuchElementException("FinanceRecord not found")))
+
+    override fun pageFinanceRecords(
+        page: Page<FinanceRecord>,
+        keyword: String?,
+        type: String?,
+        start: String?,
+        end: String?,
+        vendor: String?,
+        itemId: Long?
+    ): Mono<Page<FinanceRecord>> =
+        blockingCall {
+            logger.info("Paging finance records")
+            if (keyword.isNullOrBlank() && type.isNullOrBlank() && start.isNullOrBlank() &&
+                end.isNullOrBlank() && vendor.isNullOrBlank() && itemId == null
+            ) {
+                page(page)
+            } else {
+                val wrapper = QueryWrapper<FinanceRecord>()
+                if (!keyword.isNullOrBlank()) {
+                    wrapper.and {
+                        it.like("record_no", keyword)
+                            .or().like("vendor", keyword)
+                            .or().like("note", keyword)
+                    }
+                }
+                if (!type.isNullOrBlank()) {
+                    wrapper.eq("type", type)
+                }
+                if (!start.isNullOrBlank() && !end.isNullOrBlank()) {
+                    wrapper.apply("occurred_at BETWEEN {0} AND {1}", start, end)
+                } else if (!start.isNullOrBlank()) {
+                    wrapper.ge("occurred_at", start)
+                } else if (!end.isNullOrBlank()) {
+                    wrapper.le("occurred_at", end)
+                }
+                if (!vendor.isNullOrBlank()) {
+                    wrapper.eq("vendor", vendor)
+                }
+                if (itemId != null) {
+                    wrapper.eq("related_item_id", itemId)
+                }
+                page(page, wrapper)
+            }
+        }
+
+    override fun listByType(type: String): Mono<List<FinanceRecord>> =
+        blockingCall {
+            logger.info("Searching finance records by type")
+            ktQuery()
+                .eq(FinanceRecord::type, type)
+                .list()
+        }
+
+    override fun listByDateRange(start: String, end: String): Mono<List<FinanceRecord>> =
+        blockingCall {
+            logger.info("Searching finance records by date range")
+            ktQuery()
+                .apply("occurred_at BETWEEN {0} AND {1}", start, end)
+                .list()
+        }
+
+    override fun listByVendor(vendor: String): Mono<List<FinanceRecord>> =
+        blockingCall {
+            logger.info("Searching finance records by vendor")
+            ktQuery()
+                .eq(FinanceRecord::vendor, vendor)
+                .list()
+        }
+
+    override fun listByRelatedItem(itemId: Long): Mono<List<FinanceRecord>> =
+        blockingCall {
+            logger.info("Searching finance records by related item id")
+            ktQuery()
+                .eq(FinanceRecord::relatedItemId, itemId)
+                .list()
+        }
+
+    override fun createFinanceRecord(record: FinanceRecord): Mono<Boolean> =
+        blockingCall {
+            logger.info("Creating finance record")
+            save(record)
+        }
+
+    override fun updateFinanceRecord(record: FinanceRecord): Mono<Boolean> =
+        blockingCall {
+            logger.info("Updating finance record")
+            updateById(record)
+        }
+
+    override fun deleteFinanceRecord(id: Long): Mono<Boolean> =
+        blockingCall {
+            logger.info("Deleting finance record by id")
+            removeById(id)
+        }
+
+    override fun exportAllFinanceRecords(): Mono<List<FinanceRecord>> =
+        blockingCall {
+            logger.info("Exporting all finance records")
+            list()
+        }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/impl/ItemServiceImpl.kt

@@ -0,0 +1,145 @@
+package club.itstudio.itmanager.service.impl
+
+import club.itstudio.itmanager.entity.dto.Item
+import club.itstudio.itmanager.mapper.ItemMapper
+import club.itstudio.itmanager.service.ItemService
+import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl
+import org.slf4j.LoggerFactory
+import org.springframework.stereotype.Service
+import org.springframework.transaction.annotation.Transactional
+import reactor.core.publisher.Mono
+import reactor.core.scheduler.Schedulers
+
+@Service
+class ItemServiceImpl : ServiceImpl<ItemMapper, Item>(), ItemService {
+
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    private fun <T : Any> blockingCall(block: () -> T?): Mono<T> =
+        Mono.fromCallable(block).subscribeOn(Schedulers.boundedElastic())
+
+    override fun pageItems(page: Page<Item>, keyword: String?, status: String?): Mono<Page<Item>> =
+        blockingCall {
+            logger.info("Paging items with keyword and status")
+            if (keyword.isNullOrBlank() && status.isNullOrBlank()) {
+                page(page)
+            } else {
+                val wrapper = QueryWrapper<Item>()
+                if (!keyword.isNullOrBlank()) {
+                    wrapper.and {
+                        it.like("name", keyword)
+                            .or().like("code", keyword)
+                    }
+                }
+                if (!status.isNullOrBlank()) {
+                    wrapper.eq("status", status)
+                }
+                page(page, wrapper)
+            }
+        }
+
+    override fun getItemById(id: Long): Mono<Item> =
+        blockingCall {
+            logger.info("Searching item by id")
+            ktQuery()
+                .eq(Item::id, id)
+                .one()
+        }.switchIfEmpty(Mono.error(NoSuchElementException("Item not found")))
+
+    override fun listAvailableItems(): Mono<List<Item>> =
+        blockingCall {
+            logger.info("Listing available items")
+            ktQuery()
+                .gt(Item::availableQuantity, 0)
+                .eq(Item::status, "normal")
+                .list()
+        }
+
+    override fun listInUseItems(): Mono<List<Item>> =
+        blockingCall {
+            logger.info("Listing in-use items")
+            ktQuery()
+                .apply("total_quantity - available_quantity > 0")
+                .list()
+        }
+
+    override fun listItemsByCategory(categoryId: Long): Mono<List<Item>> =
+        blockingCall {
+            logger.info("Listing items by category")
+            ktQuery()
+                .eq(Item::categoryId, categoryId)
+                .list()
+        }
+
+    override fun createItem(item: Item): Mono<Boolean> =
+        blockingCall {
+            logger.info("Creating item")
+            save(item)
+        }
+
+    override fun updateItem(item: Item): Mono<Boolean> =
+        blockingCall {
+            logger.info("Updating item")
+            updateById(item)
+        }
+
+    override fun removeItemById(id: Long): Mono<Boolean> =
+        blockingCall {
+            logger.info("Removing item by id")
+            removeById(id)
+        }
+
+    override fun setPrimaryImage(id: Long, imagePath: String): Mono<Boolean> =
+        blockingCall {
+            logger.info("Setting primary image for item")
+            ktUpdate()
+                .eq(Item::id, id)
+                .set(Item::imagePath, imagePath)
+                .update()
+        }
+
+    override fun borrowItem(id: Long, quantity: Int): Mono<Boolean> =
+        blockingCall {
+            val item = ktQuery().eq(Item::id, id).one()
+            item != null
+                    && item.availableQuantity >= quantity
+                    && ktUpdate()
+                .eq(Item::id, id)
+                .set(Item::availableQuantity, item.availableQuantity - quantity)
+                .update()
+        }
+
+    override fun returnItem(id: Long, quantity: Int): Mono<Boolean> =
+        blockingCall {
+            val item = ktQuery().eq(Item::id, id).one()
+            item != null
+                    && item.totalQuantity >= item.availableQuantity + quantity
+                    && ktUpdate()
+                .eq(Item::id, id)
+                .set(Item::availableQuantity, item.availableQuantity + quantity)
+                .update()
+        }
+
+    @Transactional
+    override fun batchInsertItems(items: List<Item>): Mono<Boolean> =
+        blockingCall {
+            logger.info("Batch inserting items")
+            saveBatch(items)
+        }
+
+    @Transactional
+    override fun replaceAllItems(items: List<Item>): Mono<Boolean> =
+        blockingCall {
+            logger.info("Replacing all items")
+            remove(ktQuery())
+            saveBatch(items)
+        }
+
+    override fun exportAllItems(): Mono<List<Item>> =
+        blockingCall {
+            logger.info("Exporting all items")
+            list()
+        }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/impl/ItemTransactionServiceImpl.kt

@@ -0,0 +1,75 @@
+package club.itstudio.itmanager.service.impl
+
+import club.itstudio.itmanager.entity.dto.ItemTransaction
+import club.itstudio.itmanager.mapper.ItemTransactionMapper
+import club.itstudio.itmanager.service.ItemTransactionService
+import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl
+import org.slf4j.LoggerFactory
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Mono
+import reactor.core.scheduler.Schedulers
+
+@Service
+class ItemTransactionServiceImpl : ServiceImpl<ItemTransactionMapper, ItemTransaction>(), ItemTransactionService {
+
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    private fun <T : Any> blockingCall(block: () -> T?): Mono<T> =
+        Mono.fromCallable(block).subscribeOn(Schedulers.boundedElastic())
+
+    override fun getTransactionById(id: Long): Mono<ItemTransaction> =
+        blockingCall {
+            logger.info("Searching transaction by id")
+            ktQuery()
+                .eq(ItemTransaction::id, id)
+                .one()
+        }.switchIfEmpty(Mono.error(NoSuchElementException("ItemTransaction not found")))
+
+    override fun listByItem(itemId: Long): Mono<List<ItemTransaction>> =
+        blockingCall {
+            logger.info("Searching transactions by item id")
+            ktQuery()
+                .eq(ItemTransaction::itemId, itemId)
+                .list()
+        }
+
+    override fun listByType(transType: String): Mono<List<ItemTransaction>> =
+        blockingCall {
+            logger.info("Searching transactions by type")
+            ktQuery()
+                .eq(ItemTransaction::transType, transType)
+                .list()
+        }
+
+    override fun listByOperator(operatorId: Long): Mono<List<ItemTransaction>> =
+        blockingCall {
+            logger.info("Searching transactions by operator id")
+            ktQuery()
+                .eq(ItemTransaction::operatorId, operatorId)
+                .list()
+        }
+
+    override fun createTransaction(transaction: ItemTransaction): Mono<Boolean> =
+        blockingCall {
+            logger.info("Creating transaction")
+            save(transaction)
+        }
+
+    override fun updateTransaction(transaction: ItemTransaction): Mono<Boolean> =
+        blockingCall {
+            logger.info("Updating transaction")
+            updateById(transaction)
+        }
+
+    override fun deleteTransaction(id: Long): Mono<Boolean> =
+        blockingCall {
+            logger.info("Deleting transaction by id")
+            removeById(id)
+        }
+
+    override fun exportAllTransactions(): Mono<List<ItemTransaction>> =
+        blockingCall {
+            logger.info("Exporting all transactions")
+            list()
+        }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/v1/AuthorizationService.kt

@@ -0,0 +1,149 @@
+package club.itstudio.itmanager.service.v1
+
+import club.itstudio.itmanager.entity.dto.Account
+import club.itstudio.itmanager.entity.dto.EmailVerificationMsg
+import club.itstudio.itmanager.entity.enums.EmailType
+import club.itstudio.itmanager.entity.vo.request.EmailRegisterVO
+import club.itstudio.itmanager.entity.vo.request.PasswordResetVO
+import club.itstudio.itmanager.entity.vo.response.ReloginVO
+import club.itstudio.itmanager.service.AccountService
+import club.itstudio.itmanager.utils.Const
+import club.itstudio.itmanager.utils.DateUtils
+import club.itstudio.itmanager.utils.DateUtils.getCurrentDateTime
+import club.itstudio.itmanager.utils.FlowUtils
+import club.itstudio.itmanager.utils.JwtUtils
+import org.springframework.amqp.core.AmqpTemplate
+import org.springframework.data.redis.core.ReactiveStringRedisTemplate
+import org.springframework.security.crypto.password.PasswordEncoder
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Mono
+import reactor.core.scheduler.Schedulers
+import java.time.Duration
+
+@Service
+class AuthorizationService(
+    private val accountService: AccountService,
+    private val utils: FlowUtils,
+    private val jwtUtils: JwtUtils,
+    private val amqpTemplate: AmqpTemplate,
+    private val stringRedisTemplate: ReactiveStringRedisTemplate,
+    private val encoder: PasswordEncoder
+) {
+    fun askEmailVerifyCode(type: EmailType, email: String, ip: String): Mono<String> {
+        return verifyLimit(ip).flatMap { allowed ->
+            if (allowed) {
+                val code = (100000..999999).random().toString()
+                val data = EmailVerificationMsg(email, type, code)
+
+                Mono.fromRunnable<Void> {
+                    amqpTemplate.convertAndSend("mail", data)
+                }.then(
+                    stringRedisTemplate.opsForValue()
+                        .set(
+                            Const.VERIFY_EMAIL_DATA + email,
+                            code,
+                            Duration.ofMinutes(3)
+                        )
+                ).thenReturn("").subscribeOn(Schedulers.boundedElastic())
+            } else {
+                Mono.just("Request limit exceeded. Please try again later.")
+            }
+        }
+    }
+
+    fun registerEmailAccount(vo: EmailRegisterVO): Mono<String> {
+        val (email, code, username, password) = vo
+
+        return verifyCode(email, code)
+            .flatMap { result ->
+                if (result.isNotBlank()) {
+                    return@flatMap Mono.just(result)
+                }
+                accountService.existAccountByEmail(email)
+                    .flatMap { emailExists ->
+                        if (emailExists) {
+                            return@flatMap Mono.just("account with the same email already exists.")
+                        }
+                        accountService.existAccountByName(username)
+                            .flatMap { usernameExists ->
+                                if (usernameExists) {
+                                    return@flatMap Mono.just("username already exists.")
+                                }
+                                val account = Account(
+                                    id = null,
+                                    username = username,
+                                    password = encoder.encode(password)!!,
+                                    email = email,
+                                    isStaff = false,
+                                    createdAt = getCurrentDateTime()
+                                )
+                                accountService.createAccount(account)
+                                    .flatMap { success ->
+                                        if (success) {
+                                            stringRedisTemplate.delete(Const.VERIFY_EMAIL_DATA + email)
+                                                .thenReturn("")
+                                        } else {
+                                            Const.INTERNAL_ERROR_MONO
+                                        }
+                                    }
+                            }
+                    }
+            }
+    }
+
+    fun resetEmailAccountPassword(vo: PasswordResetVO): Mono<String> {
+        val (email, code, password) = vo
+
+        val encodedPassword =
+            encoder.encode(password)
+                ?: return Const.INTERNAL_ERROR_MONO
+
+        return verifyCode(email, code)
+            .then(
+                accountService.resetPasswordByEmail(
+                    email,
+                    encodedPassword
+                )
+            )
+            .then(
+                stringRedisTemplate.delete(
+                    Const.VERIFY_EMAIL_DATA + email
+                )
+            )
+            .thenReturn("Password reset successfully")
+    }
+
+    fun jwtTokenRelogin(headerToken: String?): Mono<ReloginVO>? {
+        val user = jwtUtils.resolveJwt(headerToken?.substring("Bearer ".length))
+            ?.let { jwtUtils.toUser(it) }
+            ?: return null
+        val accountMono = accountService.findAccountByName(user.username)
+        val voMono = accountMono.map {
+            ReloginVO(
+                jwtUtils.createJwt(user, it.id!!, it.username),
+                DateUtils.dateToLocalDateTime(jwtUtils.expiresTime())
+            )
+        }
+        return voMono
+    }
+
+    fun invalidateJwt(headerToken: String?): Boolean {
+        return jwtUtils.invalidateJwt(headerToken)
+    }
+
+    private fun verifyLimit(ip: String): Mono<Boolean> {
+        val key = Const.VERIFY_EMAIL_LIMIT + ip
+        return utils.limitOnceCheck(key, 60)
+    }
+
+    private fun verifyCode(email: String, receivedCode: String?): Mono<String> {
+        return stringRedisTemplate.opsForValue()
+            .get(Const.VERIFY_EMAIL_DATA + email)
+            .flatMap { code ->
+                if (receivedCode == null || code != receivedCode)
+                    Mono.just("verify code is wrong.")
+                else Mono.just("")
+            }
+            .switchIfEmpty(Mono.just("verify code has not been sent"))
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/v1/EmailApiService.kt

@@ -0,0 +1,56 @@
+package club.itstudio.itmanager.service.v1
+
+import club.itstudio.itmanager.entity.dto.EmailNotice
+import club.itstudio.itmanager.service.EmailNoticeService
+import club.itstudio.itmanager.utils.Const
+import club.itstudio.itmanager.utils.DateUtils.getCurrentDateTime
+import org.slf4j.LoggerFactory
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Mono
+import java.util.NoSuchElementException
+
+@Service
+class EmailApiService(
+    private val emailNoticeService: EmailNoticeService
+) {
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    fun getNotificationSettings(): Mono<List<EmailNotice>> {
+        logger.info("Listing notification settings and email list")
+        return emailNoticeService.listAllNotices()
+    }
+
+    fun updateNotificationSettings(notice: EmailNotice): Mono<String> {
+        logger.info("Updating notification settings")
+        if (notice.id == null) {
+            return emailNoticeService.createEmailNotice(
+                notice.copy(
+                    id = null,
+                    createdAt = getCurrentDateTime(),
+                    updatedAt = getCurrentDateTime()
+                )
+            ).flatMap { success ->
+                if (success) Mono.just("")
+                else Mono.just("notification settings create failed.")
+            }
+        }
+        return emailNoticeService.updateEmailNotice(
+            notice.copy(updatedAt = getCurrentDateTime())
+        ).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("notification settings update failed.")
+        }
+    }
+
+    fun toggleEmailStatus(id: Long?): Mono<String> {
+        logger.info("Toggling email status for id {}", id)
+        if (id == null) return Mono.just("email notice id is required.")
+        return emailNoticeService.toggleEnabled(id)
+            .flatMap { success ->
+                if (success) Mono.just("")
+                else Mono.just("email notice not found or toggle failed.")
+            }
+            .onErrorResume(NoSuchElementException::class.java) { Mono.just("email notice not found.") }
+            .onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/v1/FinanceApiService.kt

@@ -0,0 +1,217 @@
+package club.itstudio.itmanager.service.v1
+
+import club.itstudio.itmanager.entity.dto.Attachment
+import club.itstudio.itmanager.entity.dto.Category
+import club.itstudio.itmanager.entity.dto.EmailVerificationMsg
+import club.itstudio.itmanager.entity.dto.FinanceRecord
+import club.itstudio.itmanager.entity.enums.EmailType
+import club.itstudio.itmanager.service.AccountService
+import club.itstudio.itmanager.service.AttachmentService
+import club.itstudio.itmanager.service.CategoryService
+import club.itstudio.itmanager.service.FinanceRecordService
+import club.itstudio.itmanager.service.FileStorageService
+import club.itstudio.itmanager.utils.Const
+import club.itstudio.itmanager.utils.DateUtils.getCurrentDateTime
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page
+import org.slf4j.LoggerFactory
+import org.springframework.amqp.core.AmqpTemplate
+import org.springframework.http.codec.multipart.FilePart
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Flux
+import reactor.core.publisher.Mono
+import reactor.core.scheduler.Schedulers
+import java.util.NoSuchElementException
+
+@Service
+class FinanceApiService(
+    private val financeRecordService: FinanceRecordService,
+    private val categoryService: CategoryService,
+    private val attachmentService: AttachmentService,
+    private val accountService: AccountService,
+    private val amqpTemplate: AmqpTemplate,
+    private val fileStorageService: FileStorageService
+) {
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    fun getFinanceRecords(
+        page: Page<FinanceRecord>,
+        keyword: String?,
+        type: String?,
+        start: String?,
+        end: String?,
+        vendor: String?,
+        itemId: Long?
+    ): Mono<Page<FinanceRecord>> {
+        logger.info("Listing finance records")
+        return financeRecordService.pageFinanceRecords(page, keyword, type, start, end, vendor, itemId)
+    }
+
+    fun createFinanceRecord(record: FinanceRecord): Mono<String> {
+        logger.info("Creating finance record")
+        val rightNow = getCurrentDateTime()
+        return financeRecordService.createFinanceRecord(
+            record.copy(
+                id = null,
+                createdAt = rightNow
+            )
+        ).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("finance record create failed.")
+        }
+    }
+
+    fun updateFinanceRecord(record: FinanceRecord): Mono<String> {
+        logger.info("Updating finance record")
+        if (record.id == null) return Mono.just("finance record id is required.")
+        return financeRecordService.updateFinanceRecord(record).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("finance record update failed.")
+        }
+    }
+
+    fun deleteFinanceRecord(id: Long?): Mono<String> {
+        logger.info("Deleting finance record with id {}", id)
+        if (id == null) return Mono.just("finance record id is required.")
+        return financeRecordService.deleteFinanceRecord(id).flatMap { success ->
+            if (success) cleanupFinanceAttachments(id).thenReturn("")
+            else Mono.just("finance record delete failed.")
+        }
+    }
+
+    fun uploadImages(id: Long, files: Flux<FilePart>): Mono<String> {
+        logger.info("Uploading images for finance record {}", id)
+        return financeRecordService.getFinanceRecordById(id)
+            .flatMap { _ ->
+                files.flatMap { file -> saveFinanceImage(id, file) }
+                    .collectList()
+                    .flatMap { attachments ->
+                        if (attachments.isEmpty()) {
+                            Mono.just("no image files provided.")
+                        } else {
+                            Flux.fromIterable(attachments)
+                                .flatMap { attachmentService.createAttachment(it) }
+                                .collectList()
+                                .flatMap { results ->
+                                    if (results.any { !it }) {
+                                        Mono.just("finance image upload failed.")
+                                    } else {
+                                        Mono.just("")
+                                    }
+                                }
+                        }
+                    }
+            }
+            .onErrorResume(NoSuchElementException::class.java) { Mono.just("finance record not found.") }
+            .onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun deleteById(id: Long?): Mono<String> {
+        logger.info("Deleting finance record {} and notifying by email", id)
+        if (id == null) return Mono.just("finance record id is required.")
+        return financeRecordService.getFinanceRecordById(id)
+            .flatMap { record ->
+                financeRecordService.deleteFinanceRecord(id)
+                    .flatMap { success ->
+                        if (success) {
+                            cleanupFinanceAttachments(id)
+                                .then(sendFinanceDeleteNotification(record))
+                                .thenReturn("")
+                        } else {
+                            Mono.just("finance record delete failed.")
+                        }
+                    }
+            }
+            .onErrorResume(NoSuchElementException::class.java) { Mono.just("finance record not found.") }
+            .onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun getFinanceCategories(): Mono<List<Category>> {
+        logger.info("Listing finance categories")
+        return categoryService.listAllCategories()
+    }
+
+    fun createFinanceCategory(category: Category): Mono<String> {
+        logger.info("Creating finance category")
+        return categoryService.createCategory(
+            category.copy(
+                id = null,
+                createdAt = getCurrentDateTime(),
+                updatedAt = getCurrentDateTime()
+            )
+        ).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("category create failed.")
+        }
+    }
+
+    fun updateFinanceCategory(category: Category): Mono<String> {
+        logger.info("Updating finance category")
+        if (category.id == null) return Mono.just("category id is required.")
+        return categoryService.updateCategory(
+            category.copy(updatedAt = getCurrentDateTime())
+        ).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("category update failed.")
+        }
+    }
+
+    fun deleteFinanceCategory(id: Long?): Mono<String> {
+        logger.info("Deleting finance category with id {}", id)
+        if (id == null) return Mono.just("category id is required.")
+        return categoryService.deleteCategory(id).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("category delete failed.")
+        }
+    }
+
+    private fun saveFinanceImage(financeRecordId: Long, file: FilePart): Mono<Attachment> {
+        return fileStorageService.saveImage(file, "finance", financeRecordId)
+            .map { stored ->
+                Attachment(
+                    relatedTable = "finance_records",
+                    relatedId = financeRecordId,
+                    fileName = stored.path.fileName.toString(),
+                    filePath = stored.path.toString(),
+                    fileSize = stored.size,
+                    contentType = file.headers().contentType?.toString(),
+                    uploadedAt = getCurrentDateTime()
+                )
+            }
+    }
+
+    private fun cleanupFinanceAttachments(financeRecordId: Long): Mono<Boolean> {
+        return attachmentService.listByRelated("finance_records", financeRecordId)
+            .flatMap { attachments ->
+                Flux.fromIterable(attachments)
+                    .flatMap { fileStorageService.deleteFile(it.filePath) }
+                    .then(attachmentService.deleteByRelated("finance_records", financeRecordId))
+            }
+            .onErrorResume { error ->
+                logger.warn("Failed to clean up attachments for finance record {}: {}", financeRecordId, error.message)
+                Mono.just(false)
+            }
+    }
+
+    private fun sendFinanceDeleteNotification(record: FinanceRecord): Mono<Void> {
+        val recordedBy = record.recordedBy ?: return Mono.empty()
+        return accountService.findAccountById(recordedBy)
+            .flatMap { account ->
+                val email = account.email
+                if (email.isNullOrBlank()) {
+                    logger.warn("Skipping finance delete notification for record {}: no email for account {}", record.id, recordedBy)
+                    Mono.empty()
+                } else {
+                    Mono.fromRunnable<Void> {
+                        amqpTemplate.convertAndSend(
+                            "mail",
+                            EmailVerificationMsg(
+                                email = email,
+                                type = EmailType.FINANCE_DELETE,
+                                code = record.recordNo ?: record.id?.toString() ?: ""
+                            )
+                        )
+                    }.subscribeOn(Schedulers.boundedElastic())
+                }
+            }
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/v1/ItemsApiService.kt

@@ -0,0 +1,319 @@
+package club.itstudio.itmanager.service.v1
+
+import club.itstudio.itmanager.entity.dto.Attachment
+import club.itstudio.itmanager.entity.dto.Category
+import club.itstudio.itmanager.entity.dto.Item
+import club.itstudio.itmanager.entity.dto.ItemTransaction
+import club.itstudio.itmanager.entity.enums.TransactionType
+import club.itstudio.itmanager.service.AttachmentService
+import club.itstudio.itmanager.service.CategoryService
+import club.itstudio.itmanager.service.FileStorageService
+import club.itstudio.itmanager.service.ItemService
+import club.itstudio.itmanager.service.ItemTransactionService
+import club.itstudio.itmanager.utils.Const
+import club.itstudio.itmanager.utils.DateUtils.getCurrentDateTime
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page
+import org.slf4j.LoggerFactory
+import org.springframework.http.codec.multipart.FilePart
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Flux
+import reactor.core.publisher.Mono
+import java.util.NoSuchElementException
+
+@Service
+class ItemsApiService(
+    private val itemService: ItemService,
+    private val categoryService: CategoryService,
+    private val attachmentService: AttachmentService,
+    private val transactionService: ItemTransactionService,
+    private val fileStorageService: FileStorageService
+) {
+    private val logger = LoggerFactory.getLogger(this::class.java)
+    
+    fun getItems(page: Page<Item>, keyword: String?, status: String?): Mono<Page<Item>> {
+        logger.info("Listing items with keyword and status")
+        return itemService.pageItems(page, keyword, status)
+    }
+
+    fun createItem(item: Item): Mono<String> {
+        logger.info("Creating item")
+        val rightNow = getCurrentDateTime()
+        return itemService.createItem(
+            item.copy(
+                id = null,
+                createdAt = rightNow,
+                updatedAt = rightNow
+            )
+        ).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("item create failed.")
+        }
+    }
+
+    fun updateItem(item: Item): Mono<String> {
+        logger.info("Updating item")
+        if (item.id == null) return Mono.just("item id is required.")
+        return itemService.updateItem(
+            item.copy(updatedAt = getCurrentDateTime())
+        ).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("item update failed.")
+        }
+    }
+
+    fun deleteItem(id: Long?): Mono<String> {
+        logger.info("Deleting item with id {}", id)
+        if (id == null) return Mono.just("item id is required.")
+        return itemService.removeItemById(id).flatMap { success ->
+            if (success) {
+                cleanupItemAttachments(id)
+            } else {
+                Mono.just("item delete failed.")
+            }
+        }
+    }
+
+    fun uploadImages(id: Long, files: Flux<FilePart>): Mono<String> {
+        logger.info("Uploading images for item {}", id)
+        return itemService.getItemById(id)
+            .flatMap { item ->
+                files.flatMap { file -> saveItemImage(id, file) }
+                    .collectList()
+                    .flatMap { attachments ->
+                        if (attachments.isEmpty()) {
+                            Mono.just("no image files provided.")
+                        } else {
+                            Flux.fromIterable(attachments)
+                                .flatMap { attachmentService.createAttachment(it) }
+                                .collectList()
+                                .flatMap { results ->
+                                    if (results.any { !it }) {
+                                        Mono.just("item image upload failed.")
+                                    } else {
+                                        setPrimaryImageIfBlank(item, attachments.first(), id)
+                                    }
+                                }
+                        }
+                    }
+            }
+            .onErrorResume(NoSuchElementException::class.java) { Mono.just("item not found.") }
+            .onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun setPrimaryImage(id: Long, imageId: Long): Mono<String> {
+        logger.info("Setting primary image for item {}", id)
+        return itemService.getItemById(id)
+            .flatMap { _ ->
+                attachmentService.getAttachmentById(imageId)
+                    .flatMap { attachment ->
+                        if (attachment.relatedTable == "items" && attachment.relatedId == id) {
+                            val path = attachment.filePath
+                            if (path.isNullOrBlank()) {
+                                Mono.just("image file path is empty.")
+                            } else {
+                                itemService.setPrimaryImage(id, path).flatMap { success ->
+                                    if (success) Mono.just("")
+                                    else Mono.just("set primary image failed.")
+                                }
+                            }
+                        } else {
+                            Mono.just("image does not belong to this item.")
+                        }
+                    }
+                    .onErrorResume(NoSuchElementException::class.java) { _ -> Mono.just("image not found.") }
+            }
+            .onErrorResume(NoSuchElementException::class.java) { _ -> Mono.just("item not found.") }
+            .onErrorResume { _ -> Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun borrowItem(id: Long, quantity: Int): Mono<String> {
+        logger.info("Borrowing item {} with quantity {}", id, quantity)
+        if (quantity <= 0) return Mono.just("quantity must be positive.")
+        return itemService.getItemById(id)
+            .flatMap { item ->
+                itemService.borrowItem(id, quantity)
+                    .flatMap { success ->
+                        if (success) {
+                            transactionService.createTransaction(
+                                ItemTransaction(
+                                    itemId = id,
+                                    transType = TransactionType.OUT,
+                                    quantity = quantity,
+                                    fromLocation = item.location,
+                                    createdAt = getCurrentDateTime()
+                                )
+                            ).onErrorResume { error ->
+                                logger.warn("Failed to record OUT transaction for item {}: {}", id, error.message)
+                                Mono.just(false)
+                            }.thenReturn("")
+                        } else {
+                            Mono.just("item available quantity is not enough.")
+                        }
+                    }
+            }
+            .onErrorResume(NoSuchElementException::class.java) { Mono.just("item not found.") }
+            .onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun returnItem(id: Long, quantity: Int): Mono<String> {
+        logger.info("Returning item {} with quantity {}", id, quantity)
+        if (quantity <= 0) return Mono.just("quantity must be positive.")
+        return itemService.getItemById(id)
+            .flatMap { item ->
+                itemService.returnItem(id, quantity)
+                    .flatMap { success ->
+                        if (success) {
+                            transactionService.createTransaction(
+                                ItemTransaction(
+                                    itemId = id,
+                                    transType = TransactionType.IN,
+                                    quantity = quantity,
+                                    toLocation = item.location,
+                                    createdAt = getCurrentDateTime()
+                                )
+                            ).onErrorResume { error ->
+                                logger.warn("Failed to record IN transaction for item {}: {}", id, error.message)
+                                Mono.just(false)
+                            }.thenReturn("")
+                        } else {
+                            Mono.just("item cannot be returned with the given quantity.")
+                        }
+                    }
+            }
+            .onErrorResume(NoSuchElementException::class.java) { Mono.just("item not found.") }
+            .onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun getAvailableItems(): Mono<List<Item>> {
+        logger.info("Listing available items")
+        return itemService.listAvailableItems()
+    }
+
+    fun getInUseItems(): Mono<List<Item>> {
+        logger.info("Listing in-use items")
+        return itemService.listInUseItems()
+    }
+
+    fun getItemCategories(): Mono<List<Category>> {
+        logger.info("Listing item categories")
+        return categoryService.listAllCategories()
+    }
+
+    fun createItemCategory(category: Category): Mono<String> {
+        logger.info("Creating item category")
+        return categoryService.createCategory(
+            category.copy(
+                id = null,
+                createdAt = getCurrentDateTime(),
+                updatedAt = getCurrentDateTime()
+            )
+        ).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("category create failed.")
+        }
+    }
+
+    fun updateItemCategory(category: Category): Mono<String> {
+        logger.info("Updating item category")
+        if (category.id == null) return Mono.just("category id is required.")
+        return categoryService.updateCategory(
+            category.copy(updatedAt = getCurrentDateTime())
+        ).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("category update failed.")
+        }
+    }
+
+    fun deleteItemCategory(id: Long?): Mono<String> {
+        logger.info("Deleting item category with id {}", id)
+        if (id == null) return Mono.just("category id is required.")
+        return categoryService.deleteCategory(id).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("category delete failed.")
+        }
+    }
+
+    fun getItemImages(): Mono<List<Attachment>> {
+        logger.info("Listing item images")
+        return attachmentService.exportAllAttachments()
+            .map { list -> list.filter { it.relatedTable == "items" } }
+    }
+
+    fun createItemImage(attachment: Attachment): Mono<String> {
+        logger.info("Creating item image")
+        return attachmentService.createAttachment(
+            attachment.copy(
+                id = null,
+                uploadedAt = getCurrentDateTime()
+            )
+        ).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("item image create failed.")
+        }
+    }
+
+    fun updateItemImage(attachment: Attachment): Mono<String> {
+        logger.info("Updating item image")
+        if (attachment.id == null) return Mono.just("item image id is required.")
+        return attachmentService.updateAttachment(attachment)
+            .flatMap { success ->
+                if (success) Mono.just("")
+                else Mono.just("item image update failed.")
+            }
+    }
+
+    fun deleteItemImage(id: Long?): Mono<String> {
+        logger.info("Deleting item image with id {}", id)
+        if (id == null) return Mono.just("item image id is required.")
+        return attachmentService.getAttachmentById(id)
+            .flatMap { attachment ->
+                attachmentService.deleteAttachment(id).flatMap { success ->
+                    if (success) {
+                        fileStorageService.deleteFile(attachment.filePath).thenReturn("")
+                    } else {
+                        Mono.just("item image delete failed.")
+                    }
+                }
+            }
+            .onErrorResume(NoSuchElementException::class.java) { Mono.just("item image not found.") }
+            .onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    private fun setPrimaryImageIfBlank(item: Item, attachment: Attachment, id: Long): Mono<String> {
+        if (!item.imagePath.isNullOrBlank()) return Mono.just("")
+        val path = attachment.filePath ?: return Mono.just("")
+        return itemService.setPrimaryImage(id, path).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("set primary image failed.")
+        }
+    }
+
+    private fun saveItemImage(itemId: Long, file: FilePart): Mono<Attachment> {
+        return fileStorageService.saveImage(file, "items", itemId)
+            .map { stored ->
+                Attachment(
+                    relatedTable = "items",
+                    relatedId = itemId,
+                    fileName = stored.path.fileName.toString(),
+                    filePath = stored.path.toString(),
+                    fileSize = stored.size,
+                    contentType = file.headers().contentType?.toString(),
+                    uploadedAt = getCurrentDateTime()
+                )
+            }
+    }
+
+    private fun cleanupItemAttachments(itemId: Long): Mono<String> {
+        return attachmentService.listByRelated("items", itemId)
+            .flatMap { attachments ->
+                Flux.fromIterable(attachments)
+                    .flatMap { fileStorageService.deleteFile(it.filePath) }
+                    .then(attachmentService.deleteByRelated("items", itemId))
+                    .thenReturn("")
+            }
+            .onErrorResume { error ->
+                logger.warn("Failed to clean up attachments for item {}: {}", itemId, error.message)
+                Mono.just("")
+            }
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/v1/ProofImagesApiService.kt

@@ -0,0 +1,83 @@
+package club.itstudio.itmanager.service.v1
+
+import club.itstudio.itmanager.entity.dto.Attachment
+import club.itstudio.itmanager.service.AttachmentService
+import club.itstudio.itmanager.utils.Const
+import club.itstudio.itmanager.utils.DateUtils.getCurrentDateTime
+import org.slf4j.LoggerFactory
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Mono
+import reactor.core.scheduler.Schedulers
+import java.io.IOException
+import java.nio.file.Files
+import java.nio.file.Paths
+import java.util.NoSuchElementException
+
+@Service
+class ProofImagesApiService(
+    private val attachmentService: AttachmentService
+) {
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    fun getProofImages(): Mono<List<Attachment>> {
+        logger.info("Listing proof images")
+        return attachmentService.exportAllAttachments()
+            .map { list -> list.filter { it.relatedTable == RELATED_TABLE } }
+    }
+
+    fun createProofImage(attachment: Attachment): Mono<String> {
+        logger.info("Creating proof image")
+        return attachmentService.createAttachment(
+            attachment.copy(
+                id = null,
+                uploadedAt = getCurrentDateTime()
+            )
+        ).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("proof image create failed.")
+        }.onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun updateProofImage(attachment: Attachment): Mono<String> {
+        logger.info("Updating proof image")
+        if (attachment.id == null) return Mono.just("proof image id is required.")
+        return attachmentService.updateAttachment(attachment)
+            .flatMap { success ->
+                if (success) Mono.just("")
+                else Mono.just("proof image update failed.")
+            }
+            .onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun deleteProofImage(id: Long?): Mono<String> {
+        logger.info("Deleting proof image with id {}", id)
+        if (id == null) return Mono.just("proof image id is required.")
+        return attachmentService.getAttachmentById(id)
+            .flatMap { attachment ->
+                attachmentService.deleteAttachment(id).flatMap { success ->
+                    if (success) {
+                        deletePhysicalFile(attachment.filePath).thenReturn("")
+                    } else {
+                        Mono.just("proof image delete failed.")
+                    }
+                }
+            }
+            .onErrorResume(NoSuchElementException::class.java) { Mono.just("proof image not found.") }
+            .onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    private fun deletePhysicalFile(path: String?): Mono<Void> {
+        if (path.isNullOrBlank()) return Mono.empty()
+        return Mono.fromRunnable<Void> {
+            try {
+                Files.deleteIfExists(Paths.get(path))
+            } catch (e: IOException) {
+                logger.warn("Failed to delete file: {}", path, e)
+            }
+        }.subscribeOn(Schedulers.boundedElastic())
+    }
+
+    companion object {
+        private const val RELATED_TABLE = "finance_records"
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/service/v1/UsagesApiService.kt

@@ -0,0 +1,188 @@
+package club.itstudio.itmanager.service.v1
+
+import club.itstudio.itmanager.entity.dto.Attachment
+import club.itstudio.itmanager.entity.dto.BorrowRecord
+import club.itstudio.itmanager.service.AttachmentService
+import club.itstudio.itmanager.service.BorrowRecordService
+import club.itstudio.itmanager.service.FileStorageService
+import club.itstudio.itmanager.utils.Const
+import club.itstudio.itmanager.utils.DateUtils.getCurrentDateTime
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page
+import org.slf4j.LoggerFactory
+import org.springframework.http.codec.multipart.FilePart
+import org.springframework.stereotype.Service
+import reactor.core.publisher.Flux
+import reactor.core.publisher.Mono
+import java.util.NoSuchElementException
+
+@Service
+class UsagesApiService(
+    private val borrowRecordService: BorrowRecordService,
+    private val attachmentService: AttachmentService,
+    private val fileStorageService: FileStorageService
+) {
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
+    fun getUsages(page: Page<BorrowRecord>, keyword: String?, status: String?): Mono<Page<BorrowRecord>> {
+        logger.info("Paging usages with keyword and status")
+        return borrowRecordService.pageUsages(page, keyword, status)
+    }
+
+    fun createUsage(record: BorrowRecord): Mono<String> {
+        logger.info("Creating usage")
+        val rightNow = getCurrentDateTime()
+        return borrowRecordService.createBorrowRecord(
+            record.copy(
+                id = null,
+                createdAt = rightNow,
+                updatedAt = rightNow
+            )
+        ).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("usage create failed.")
+        }.onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun updateUsage(record: BorrowRecord): Mono<String> {
+        logger.info("Updating usage")
+        if (record.id == null) return Mono.just("usage id is required.")
+        return borrowRecordService.updateBorrowRecord(
+            record.copy(updatedAt = getCurrentDateTime())
+        ).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("usage update failed.")
+        }.onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun deleteUsage(id: Long?): Mono<String> {
+        logger.info("Deleting usage with id {}", id)
+        if (id == null) return Mono.just("usage id is required.")
+        return borrowRecordService.deleteBorrowRecord(id).flatMap { success ->
+            if (success) {
+                cleanupUsageAttachments(id)
+            } else {
+                Mono.just("usage delete failed.")
+            }
+        }.onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun uploadImages(id: Long, files: Flux<FilePart>): Mono<String> {
+        logger.info("Uploading images for usage {}", id)
+        return borrowRecordService.getBorrowRecordById(id)
+            .flatMap { _ ->
+                files.flatMap { file -> saveUsageImage(id, file) }
+                    .collectList()
+                    .flatMap { attachments ->
+                        if (attachments.isEmpty()) {
+                            Mono.just("no image files provided.")
+                        } else {
+                            Flux.fromIterable(attachments)
+                                .flatMap { attachmentService.createAttachment(it) }
+                                .collectList()
+                                .flatMap { results ->
+                                    if (results.any { !it }) {
+                                        Mono.just("usage image upload failed.")
+                                    } else {
+                                        Mono.just("")
+                                    }
+                                }
+                        }
+                    }
+            }
+            .onErrorResume(NoSuchElementException::class.java) { Mono.just("usage not found.") }
+            .onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun getCurrentUsages(): Mono<List<BorrowRecord>> {
+        logger.info("Listing current usages")
+        return borrowRecordService.listByStatus(STATUS_BORROWED)
+            .zipWith(borrowRecordService.listOverdueRecords()) { borrowed, overdue -> borrowed + overdue }
+    }
+
+    fun getUsagesByUser(name: String?): Mono<List<BorrowRecord>> {
+        logger.info("Listing usages by user {}", name)
+        if (name.isNullOrBlank()) return Mono.just(emptyList())
+        return borrowRecordService.listByBorrower(name)
+    }
+
+    fun getUsageImages(): Mono<List<Attachment>> {
+        logger.info("Listing usage images")
+        return attachmentService.exportAllAttachments()
+            .map { list -> list.filter { it.relatedTable == RELATED_TABLE } }
+    }
+
+    fun createUsageImage(attachment: Attachment): Mono<String> {
+        logger.info("Creating usage image")
+        return attachmentService.createAttachment(
+            attachment.copy(
+                id = null,
+                uploadedAt = getCurrentDateTime()
+            )
+        ).flatMap { success ->
+            if (success) Mono.just("")
+            else Mono.just("usage image create failed.")
+        }.onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun updateUsageImage(attachment: Attachment): Mono<String> {
+        logger.info("Updating usage image")
+        if (attachment.id == null) return Mono.just("usage image id is required.")
+        return attachmentService.updateAttachment(attachment)
+            .flatMap { success ->
+                if (success) Mono.just("")
+                else Mono.just("usage image update failed.")
+            }
+            .onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    fun deleteUsageImage(id: Long?): Mono<String> {
+        logger.info("Deleting usage image with id {}", id)
+        if (id == null) return Mono.just("usage image id is required.")
+        return attachmentService.getAttachmentById(id)
+            .flatMap { attachment ->
+                attachmentService.deleteAttachment(id).flatMap { success ->
+                    if (success) {
+                        fileStorageService.deleteFile(attachment.filePath).thenReturn("")
+                    } else {
+                        Mono.just("usage image delete failed.")
+                    }
+                }
+            }
+            .onErrorResume(NoSuchElementException::class.java) { Mono.just("usage image not found.") }
+            .onErrorResume { Mono.just(Const.INTERNAL_ERROR_STR) }
+    }
+
+    private fun saveUsageImage(usageId: Long, file: FilePart): Mono<Attachment> {
+        return fileStorageService.saveImage(file, "borrow_records", usageId)
+            .map { stored ->
+                Attachment(
+                    relatedTable = RELATED_TABLE,
+                    relatedId = usageId,
+                    fileName = stored.path.fileName.toString(),
+                    filePath = stored.path.toString(),
+                    fileSize = stored.size,
+                    contentType = file.headers().contentType?.toString(),
+                    uploadedAt = getCurrentDateTime()
+                )
+            }
+    }
+
+    private fun cleanupUsageAttachments(usageId: Long): Mono<String> {
+        return attachmentService.listByRelated(RELATED_TABLE, usageId)
+            .flatMap { attachments ->
+                Flux.fromIterable(attachments)
+                    .flatMap { fileStorageService.deleteFile(it.filePath) }
+                    .then(attachmentService.deleteByRelated(RELATED_TABLE, usageId))
+                    .thenReturn("")
+            }
+            .onErrorResume { error ->
+                logger.warn("Failed to clean up attachments for usage {}: {}", usageId, error.message)
+                Mono.just("")
+            }
+    }
+
+    companion object {
+        private const val RELATED_TABLE = "borrow_records"
+        private const val STATUS_BORROWED = "BORROWED"
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/utils/BigDecimalSerializer.kt

@@ -0,0 +1,29 @@
+package club.itstudio.itmanager.utils
+
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.SerializationException
+import kotlinx.serialization.descriptors.PrimitiveKind
+import kotlinx.serialization.descriptors.PrimitiveSerialDescriptor
+import kotlinx.serialization.descriptors.SerialDescriptor
+import kotlinx.serialization.encoding.Decoder
+import kotlinx.serialization.encoding.Encoder
+import kotlinx.serialization.json.JsonDecoder
+import kotlinx.serialization.json.JsonPrimitive
+import java.math.BigDecimal
+
+object BigDecimalSerializer : KSerializer<BigDecimal> {
+    override val descriptor: SerialDescriptor =
+        PrimitiveSerialDescriptor("BigDecimal", PrimitiveKind.STRING)
+
+    override fun serialize(encoder: Encoder, value: BigDecimal) {
+        encoder.encodeString(value.toPlainString())
+    }
+
+    override fun deserialize(decoder: Decoder): BigDecimal {
+        val element = (decoder as JsonDecoder).decodeJsonElement()
+        if (element !is JsonPrimitive) {
+            throw SerializationException("Expected JSON primitive, got $element")
+        }
+        return element.content.toBigDecimal()
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/utils/Const.kt

@@ -0,0 +1,29 @@
+package club.itstudio.itmanager.utils
+
+import club.itstudio.itmanager.entity.ApiResponse
+import reactor.core.publisher.Mono
+
+object Const {
+    const val FLOW_LIMIT_ORDER = -101
+
+    const val JWT_BLACK_LIST = "jwt:blacklist:"
+    const val VERIFY_EMAIL_LIMIT = "verify:email:limit:"
+    const val VERIFY_EMAIL_DATA = "verify:email:data:"
+
+    const val FLOW_LIMIT_COUNTER = "flow:counter:"
+    const val FLOW_LIMIT_BLOCK = "flow:block:"
+
+    const val FILE_DIR_IMAGE = "image"
+
+    const val INTERNAL_ERROR_STR = "something went wrong. Please contact the administrator."
+    val INTERNAL_ERROR_MONO = Mono.just(INTERNAL_ERROR_STR)
+
+    // for Controllers
+    fun messageHandler(wrongMessage: String): ApiResponse<Any?> {
+        return if (wrongMessage.isBlank()) {
+            ApiResponse.success()
+        } else {
+            ApiResponse.failure(400, null, wrongMessage)
+        }
+    }
+}

src/backend/src/main/kotlin/club/itstudio/itmanager/utils/JwtUtils.kt

@@ -4,26 +4,28 @@ import com.auth0.jwt.JWT
 import com.auth0.jwt.JWTVerifier
 import com.auth0.jwt.algorithms.Algorithm
 import com.auth0.jwt.interfaces.DecodedJWT
+import org.slf4j.LoggerFactory
 import org.springframework.beans.factory.annotation.Value
 import org.springframework.data.redis.core.StringRedisTemplate
 import org.springframework.security.core.userdetails.User
 import org.springframework.security.core.userdetails.UserDetails
 import org.springframework.stereotype.Component
+import java.time.Duration
 import java.util.*
-import java.util.concurrent.TimeUnit
 
 @Component
 class JwtUtils(
     @param:Value($$"${spring.security.jwt.key}")
     private val key: String,
-
     @param:Value($$"${spring.security.jwt.expire-hours}")
     private val expireHours: Int,
 
-    private val template: StringRedisTemplate,
-    private val algorithm: Algorithm = Algorithm.HMAC256(key),
-    private val jwtVerifier: JWTVerifier = JWT.require(algorithm).build()
+    private val template: StringRedisTemplate
 ) {
+    private val algorithm: Algorithm = Algorithm.HMAC256(key)
+    private val jwtVerifier: JWTVerifier = JWT.require(algorithm).build()
+    private val logger = LoggerFactory.getLogger(this::class.java)
+
     fun invalidateJwt(headerToken: String?): Boolean {
         val token = this.convertToToken(headerToken) ?: return false
         try {
@@ -31,7 +33,7 @@ class JwtUtils(
             val id = jwt.id
             return deleteToken(id, jwt.expiresAt)
         } catch (e: Exception) {
-            println(e.message)
+            logger.error("Error occurred while invalidating JWT", e)
             return false
         }
     }
@@ -42,8 +44,7 @@ class JwtUtils(
         template.opsForValue().set(
             Const.JWT_BLACK_LIST + uuid,
             "deleted",
-            expire,
-            TimeUnit.MILLISECONDS
+            Duration.ofMillis(expire)
         )
         return true
     }
@@ -62,14 +63,14 @@ class JwtUtils(
             else decodedJWT
 
         } catch (e: Exception) {
-            println(e.message)
+            logger.error("Error occurred while resolving JWT", e)
             return null
         }
     }
 
     fun createJwt(
         details: UserDetails,
-        id: Int,
+        id: Long,
         username: String
     ): String {
         return JWT.create()
@@ -94,7 +95,7 @@ class JwtUtils(
             .build()
     }
 
-    fun toId(jwt: DecodedJWT) = jwt.claims["id"]?.asInt() ?: -1
+    fun toId(jwt: DecodedJWT) = jwt.claims["id"]?.asLong() ?: -1L
 
     fun expiresTime(): Date {
         val cal = Calendar.getInstance()
@@ -102,6 +103,8 @@ class JwtUtils(
         return cal.time
     }
 
-    fun convertToToken(headerToken: String?): String? =
-        headerToken?.replace("Bearer ", "")
+    fun convertToToken(headerToken: String?): String? {
+        val token = headerToken?.replace("Bearer ", "")?.trim()
+        return token?.takeIf { it.isNotEmpty() }
+    }
 }

src/backend/src/main/resources/application.yaml

@@ -1,4 +1,7 @@
 spring:
+  profiles:
+    active: private
+  
   webflux:
     base-path: /
   
@@ -17,28 +20,30 @@ spring:
     host: localhost
     port: 5672
     virtual-host: /
-    username: admin
-    password: 123456
+    #username: admin
+    #password: 123456
   
   application:
     name: itmanager
   
   security:
     jwt:
-      key: 6846513216
+      #key: 6846513216
       expire-hours: 168
 
   datasource:
-    url: jdbc:mariadb://localhost:3306/kotlin_springboot
+    url: jdbc:mariadb://localhost:3306/itstudio_manager
     driver-class-name: org.mariadb.jdbc.Driver
-    username: root
-    password: 123456
+    #username: root
+    #password: 123456
 
 mybatis-plus:
-  type-handlers-package: com.github.sor2171.backend.config
+  type-handlers-package: club.itstudio.itmanager.mapper.typehandler
 
 app:
   flow-limit:
     count: 1000
     limit-time: 3
     ban-time: 60
+  file:
+    data-path: ./data

src/backend/src/test/kotlin/club/itstudio/itmanager/ItmanagerApplicationTests.kt

@@ -2,12 +2,14 @@ package club.itstudio.itmanager
 
 import org.junit.jupiter.api.Test
 import org.springframework.boot.test.context.SpringBootTest
+import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder
 
 @SpringBootTest
 class ItmanagerApplicationTests {
 
     @Test
     fun contextLoads() {
+        println(BCryptPasswordEncoder().encode("123456"))
     }
 
 }

src/beckend/gradle/wrapper/gradle-wrapper.properties

@@ -1,9 +0,0 @@
-distributionBase=GRADLE_USER_HOME
-distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-9.5.1-bin.zip
-networkTimeout=10000
-retries=0
-retryBackOffMs=500
-validateDistributionUrl=true
-zipStoreBase=GRADLE_USER_HOME
-zipStorePath=wrapper/dists

src/beckend/src/main/kotlin/club/itstudio/itmanager/controller/v1/DepartmentsController.kt

@@ -1,11 +0,0 @@
-package club.itstudio.itmanager.controller.v1
-
-import org.springframework.validation.annotation.Validated
-import org.springframework.web.bind.annotation.RequestMapping
-import org.springframework.web.bind.annotation.RestController
-
-@Validated
-@RestController
-@RequestMapping("/api/v1/department")
-class DepartmentsController {
-}

src/beckend/src/main/kotlin/club/itstudio/itmanager/controller/v1/EmailController.kt

@@ -1,11 +0,0 @@
-package club.itstudio.itmanager.controller.v1
-
-import org.springframework.validation.annotation.Validated
-import org.springframework.web.bind.annotation.RequestMapping
-import org.springframework.web.bind.annotation.RestController
-
-@Validated
-@RestController
-@RequestMapping("/api/v1/email")
-class EmailController {
-}

src/beckend/src/main/kotlin/club/itstudio/itmanager/controller/v1/EvaluationRecordsController.kt

@@ -1,11 +0,0 @@
-package club.itstudio.itmanager.controller.v1
-
-import org.springframework.validation.annotation.Validated
-import org.springframework.web.bind.annotation.RequestMapping
-import org.springframework.web.bind.annotation.RestController
-
-@Validated
-@RestController
-@RequestMapping("/api/v1/evaluation-records")
-class EvaluationRecordsController {
-}