diff --git a/cloudfunctions/userDownloadLogs/index.js b/cloudfunctions/userDownloadLogs/index.js
new file mode 100644
index 0000000..6586b36
--- /dev/null
+++ b/cloudfunctions/userDownloadLogs/index.js
@@ -0,0 +1,98 @@
+const cloud = require('wx-server-sdk');
+cloud.init({ env: cloud.DYNAMIC_CURRENT_ENV });
+
+const db = cloud.database();
+const command = db.command;
+
+exports.main = async (event) => {
+    const wxContext = cloud.getWXContext();
+    const openid = wxContext.OPENID;
+
+    // 获取 userId
+    const { data: users } = await db
+        .collection('users')
+        .where({ openid })
+        .limit(1)
+        .get();
+
+    if (users.length === 0) {
+        return { code: -1, message: '用户未登录' };
+    }
+
+    const userId = users[0]._id;
+    const { action } = event;
+
+    switch (action) {
+        case 'add':
+            return await handleAdd(userId, event);
+        case 'list':
+            return await handleList(userId, event);
+        default:
+            return { code: -1, message: '未知操作' };
+    }
+};
+
+async function handleAdd(userId, event) {
+    const { worksheetId } = event;
+    if (!worksheetId) return { code: -1, message: 'worksheetId 不能为空' };
+
+    const collection = db.collection('download_logs');
+
+    const record = {
+        userId,
+        worksheetId,
+        createdAt: db.serverDate(),
+    };
+    const { _id } = await collection.add({ data: record });
+
+    // worksheets.downloads +1
+    try {
+        await db.collection('worksheets').doc(worksheetId).update({
+            data: {
+                downloads: command.inc(1),
+                updatedAt: db.serverDate(),
+            },
+        });
+    } catch (e) {
+        console.warn('更新 worksheets.downloads 失败', e);
+    }
+
+    return { code: 0, data: { _id, ...record } };
+}
+
+async function handleList(userId, event) {
+    const { page = 1, pageSize = 20 } = event;
+    const skip = (page - 1) * pageSize;
+
+    const collection = db.collection('download_logs');
+
+    const { data: logs } = await collection
+        .where({ userId })
+        .orderBy('createdAt', 'desc')
+        .skip(skip)
+        .limit(pageSize)
+        .get();
+
+    if (logs.length === 0) {
+        return { code: 0, data: [] };
+    }
+
+    // 关联查询 worksheets 信息
+    const worksheetIds = [...new Set(logs.map((l) => l.worksheetId))];
+    const { data: worksheets } = await db
+        .collection('worksheets')
+        .where({ _id: command.in(worksheetIds) })
+        .get();
+
+    const worksheetMap = {};
+    worksheets.forEach((w) => {
+        worksheetMap[w._id] = w;
+    });
+
+    const result = logs.map((l) => ({
+        ...l,
+        worksheet: worksheetMap[l.worksheetId] || null,
+    }));
+
+    return { code: 0, data: result };
+}
diff --git a/cloudfunctions/userDownloadLogs/package.json b/cloudfunctions/userDownloadLogs/package.json
new file mode 100644
index 0000000..25915dd
--- /dev/null
+++ b/cloudfunctions/userDownloadLogs/package.json
@@ -0,0 +1,8 @@
+{
+    "name": "user-download-logs",
+    "version": "1.0.0",
+    "main": "index.js",
+    "dependencies": {
+        "wx-server-sdk": "^3.0.4"
+    }
+}
diff --git a/cloudfunctions/userFavorites/index.js b/cloudfunctions/userFavorites/index.js
new file mode 100644
index 0000000..451f54f
--- /dev/null
+++ b/cloudfunctions/userFavorites/index.js
@@ -0,0 +1,190 @@
+const cloud = require('wx-server-sdk');
+cloud.init({ env: cloud.DYNAMIC_CURRENT_ENV });
+
+const db = cloud.database();
+const command = db.command;
+
+exports.main = async (event) => {
+    const wxContext = cloud.getWXContext();
+    const openid = wxContext.OPENID;
+
+    // 获取 userId
+    const { data: users } = await db
+        .collection('users')
+        .where({ openid })
+        .limit(1)
+        .get();
+
+    if (users.length === 0) {
+        return { code: -1, message: '用户未登录' };
+    }
+
+    const userId = users[0]._id;
+    const { action } = event;
+
+    switch (action) {
+        case 'add':
+            return await handleAdd(userId, event);
+        case 'remove':
+            return await handleRemove(userId, event);
+        case 'list':
+            return await handleList(userId, event);
+        case 'check':
+            return await handleCheck(userId, event);
+        case 'batchCheck':
+            return await handleBatchCheck(userId, event);
+        default:
+            return { code: -1, message: '未知操作' };
+    }
+};
+
+async function handleAdd(userId, event) {
+    const { worksheetId } = event;
+    if (!worksheetId) return { code: -1, message: 'worksheetId 不能为空' };
+
+    const collection = db.collection('favorites');
+
+    // 幂等检查：已收藏则直接返回
+    const { data: existing } = await collection
+        .where({ userId, worksheetId })
+        .limit(1)
+        .get();
+
+    if (existing.length > 0) {
+        return { code: 0, data: existing[0], message: '已收藏' };
+    }
+
+    // 写入收藏记录
+    const record = {
+        userId,
+        worksheetId,
+        createdAt: db.serverDate(),
+    };
+    const { _id } = await collection.add({ data: record });
+
+    // worksheets.likes +1
+    try {
+        await db
+            .collection('worksheets')
+            .doc(worksheetId)
+            .update({
+                data: {
+                    likes: command.inc(1),
+                    updatedAt: db.serverDate(),
+                },
+            });
+    } catch (e) {
+        console.warn('更新 worksheets.likes 失败', e);
+    }
+
+    return { code: 0, data: { _id, ...record } };
+}
+
+async function handleRemove(userId, event) {
+    const { worksheetId } = event;
+    if (!worksheetId) return { code: -1, message: 'worksheetId 不能为空' };
+
+    const collection = db.collection('favorites');
+
+    const { data: existing } = await collection
+        .where({ userId, worksheetId })
+        .limit(1)
+        .get();
+
+    if (existing.length === 0) {
+        return { code: 0, message: '未收藏' };
+    }
+
+    await collection.doc(existing[0]._id).remove();
+
+    // worksheets.likes -1
+    try {
+        await db
+            .collection('worksheets')
+            .doc(worksheetId)
+            .update({
+                data: {
+                    likes: command.inc(-1),
+                    updatedAt: db.serverDate(),
+                },
+            });
+    } catch (e) {
+        console.warn('更新 worksheets.likes 失败', e);
+    }
+
+    return { code: 0, message: '已取消收藏' };
+}
+
+async function handleList(userId, event) {
+    const { page = 1, pageSize = 20 } = event;
+    const skip = (page - 1) * pageSize;
+
+    const collection = db.collection('favorites');
+
+    // 查询收藏记录
+    const { data: favorites } = await collection
+        .where({ userId })
+        .orderBy('createdAt', 'desc')
+        .skip(skip)
+        .limit(pageSize)
+        .get();
+
+    if (favorites.length === 0) {
+        return { code: 0, data: [] };
+    }
+
+    // 关联查询 worksheets 信息
+    const worksheetIds = favorites.map((f) => f.worksheetId);
+    const { data: worksheets } = await db
+        .collection('worksheets')
+        .where({ _id: command.in(worksheetIds) })
+        .get();
+
+    const worksheetMap = {};
+    worksheets.forEach((w) => {
+        worksheetMap[w._id] = w;
+    });
+
+    const result = favorites.map((f) => ({
+        ...f,
+        worksheet: worksheetMap[f.worksheetId] || null,
+    }));
+
+    return { code: 0, data: result };
+}
+
+async function handleCheck(userId, event) {
+    const { worksheetId } = event;
+    if (!worksheetId) return { code: -1, message: 'worksheetId 不能为空' };
+
+    const { data } = await db
+        .collection('favorites')
+        .where({ userId, worksheetId })
+        .limit(1)
+        .get();
+
+    return { code: 0, data: { favorited: data.length > 0 } };
+}
+
+async function handleBatchCheck(userId, event) {
+    const { worksheetIds } = event;
+    if (
+        !worksheetIds ||
+        !Array.isArray(worksheetIds) ||
+        worksheetIds.length === 0
+    ) {
+        return { code: 0, data: {} };
+    }
+
+    const { data } = await db
+        .collection('favorites')
+        .where({ userId, worksheetId: command.in(worksheetIds) })
+        .get();
+
+    const favoritedMap = {};
+    data.forEach((item) => {
+        favoritedMap[item.worksheetId] = true;
+    });
+
+    return { code: 0, data: favoritedMap };
+}
diff --git a/cloudfunctions/userFavorites/package.json b/cloudfunctions/userFavorites/package.json
new file mode 100644
index 0000000..0d436a1
--- /dev/null
+++ b/cloudfunctions/userFavorites/package.json
@@ -0,0 +1,8 @@
+{
+    "name": "user-favorites",
+    "version": "1.0.0",
+    "main": "index.js",
+    "dependencies": {
+        "wx-server-sdk": "^3.0.4"
+    }
+}
diff --git a/cloudfunctions/userLogin/index.js b/cloudfunctions/userLogin/index.js
new file mode 100644
index 0000000..d887c18
--- /dev/null
+++ b/cloudfunctions/userLogin/index.js
@@ -0,0 +1,84 @@
+const cloud = require('wx-server-sdk');
+cloud.init({ env: cloud.DYNAMIC_CURRENT_ENV });
+
+const db = cloud.database();
+
+exports.main = async (event, context) => {
+    const wxContext = cloud.getWXContext();
+    const openid = wxContext.OPENID;
+    const unionid = wxContext.UNIONID || null;
+
+    const { action } = event;
+
+    switch (action) {
+        case 'updateProfile':
+            return await handleUpdateProfile(event, openid);
+        default:
+            return await handleSilentLogin(openid, unionid);
+    }
+};
+
+async function handleSilentLogin(openid, unionid) {
+    const usersCollection = db.collection('users');
+
+    const { data } = await usersCollection.where({ openid }).limit(1).get();
+
+    const now = db.serverDate();
+
+    if (data.length > 0) {
+        const user = data[0];
+        const updateData = { lastActiveAt: now };
+        if (unionid && !user.unionid) {
+            updateData.unionid = unionid;
+        }
+        await usersCollection.doc(user._id).update({ data: updateData });
+
+        return {
+            code: 0,
+            data: { ...user, ...updateData, lastActiveAt: new Date() },
+        };
+    } else {
+        const newUser = {
+            openid,
+            unionid,
+            nickName: null,
+            avatarUrl: null,
+            totalDownloads: 0,
+            createdAt: now,
+            lastActiveAt: now,
+        };
+        const { _id } = await usersCollection.add({ data: newUser });
+
+        return {
+            code: 0,
+            data: {
+                _id,
+                ...newUser,
+                createdAt: new Date(),
+                lastActiveAt: new Date(),
+            },
+        };
+    }
+}
+
+async function handleUpdateProfile(event, openid) {
+    const { nickName, avatarUrl } = event;
+    const usersCollection = db.collection('users');
+
+    const { data } = await usersCollection.where({ openid }).limit(1).get();
+
+    if (data.length === 0) {
+        return { code: -1, message: '用户不存在' };
+    }
+
+    const updateData = {};
+    if (nickName !== undefined) updateData.nickName = nickName;
+    if (avatarUrl !== undefined) updateData.avatarUrl = avatarUrl;
+
+    await usersCollection.doc(data[0]._id).update({ data: updateData });
+
+    return {
+        code: 0,
+        data: { ...data[0], ...updateData },
+    };
+}
diff --git a/cloudfunctions/userLogin/package.json b/cloudfunctions/userLogin/package.json
new file mode 100644
index 0000000..8fad6ca
--- /dev/null
+++ b/cloudfunctions/userLogin/package.json
@@ -0,0 +1,8 @@
+{
+    "name": "user-login",
+    "version": "1.0.0",
+    "main": "index.js",
+    "dependencies": {
+        "wx-server-sdk": "^3.0.4"
+    }
+}
diff --git a/docs/小程序云开发方案和数据库设计.md b/docs/小程序云开发方案和数据库设计.md
index 130703d..a35d14a 100644
--- a/docs/小程序云开发方案和数据库设计.md
+++ b/docs/小程序云开发方案和数据库设计.md
@@ -125,16 +125,15 @@
 
 对应 Prisma `User`（`@@map("users")`）。**`openid` / `unionid` 与 `_id` 的取舍、`unionid` 写入方式**见 §3.2。
 
-| 字段             | BSON 类型      | 必填 | 说明                                                                                                  |
-| ---------------- | -------------- | ---- | ----------------------------------------------------------------------------------------------------- |
-| `_id`            | string         | 是   | 主键；可与 Prisma `User.id` 一样使用 cuid，也可自定义为其它字符串，团队内与用户档案查询方式统一即可。 |
-| `openid`         | string         | 是   | 当前小程序下微信用户标识；与 Prisma 一致建议 ≤100 字符；**业务唯一**，索引见下表。                    |
-| `unionid`        | string \| null | 否   | 开放平台下跨应用用户标识；建议 ≤100 字符；未绑开放平台或未返回时为空。                                |
-| `nickName`       | string \| null | 否   | 用户昵称；建议 ≤50 字符。                                                                             |
-| `avatarUrl`      | string \| null | 否   | 头像 URL 或云存储 fileID；建议 ≤500 字符。                                                            |
-| `totalDownloads` | int            | 是   | 累计下载次数，默认 `0`。                                                                              |
-| `createdAt`      | date           | 是   | 首次创建时间。                                                                                        |
-| `lastActiveAt`   | date           | 是   | 最近一次活跃时间（登录、打开小程序、写库等策略由实现约定）。                                          |
+| 字段           | BSON 类型      | 必填 | 说明                                                                                                  |
+| -------------- | -------------- | ---- | ----------------------------------------------------------------------------------------------------- | ----- |
+| `_id`          | string         | 是   | 主键；可与 Prisma `User.id` 一样使用 cuid，也可自定义为其它字符串，团队内与用户档案查询方式统一即可。 |
+| `openid`       | string         | 是   | 当前小程序下微信用户标识；与 Prisma 一致建议 ≤100 字符；**业务唯一**，索引见下表。                    |
+| `unionid`      | string \| null | 否   | 开放平台下跨应用用户标识；建议 ≤100 字符；未绑开放平台或未返回时为空。                                |
+| `nickName`     | string \| null | 否   | 用户昵称；建议 ≤50 字符。                                                                             |
+| `avatarUrl`    | string \| null | 否   | 头像 URL 或云存储 fileID；建议 ≤500 字符。                                                            | `0`。 |
+| `createdAt`    | date           | 是   | 首次创建时间。                                                                                        |
+| `lastActiveAt` | date           | 是   | 最近一次活跃时间（登录、打开小程序、写库等策略由实现约定）。                                          |
 
 **索引建议**
 
@@ -145,7 +144,7 @@
 
 ---
 
-### 3.6 集合：`favorites`（收藏日志）
+### 3.6 集合：`favorites_log`（收藏日志）
 
 对应 Prisma `FavoriteLog`。
 
diff --git a/docs/用户登录与信息授权方案.md b/docs/用户登录与信息授权方案.md
new file mode 100644
index 0000000..9f1dff6
--- /dev/null
+++ b/docs/用户登录与信息授权方案.md
@@ -0,0 +1,338 @@
+# 用户登录与信息授权方案
+
+> 版本：v1.0
+> 最后更新：2026-05-06
+> 适用范围：微信小程序云开发环境下的用户身份管理
+
+---
+
+## 一、方案概述
+
+采用**静默登录**策略：用户进入小程序后无感知地完成身份识别与用户创建，不弹出任何授权弹窗。昵称和头像等个人信息在后续需要时（如个人中心、评论等场景）再引导用户主动授权。
+
+**核心流程**：
+
+```
+用户打开小程序
+    │
+    ├─ 本地 Storage 有用户数据且未过期？
+    │       │
+    │       ├─ 是 → 直接使用本地数据，跳过登录
+    │       │
+    │       └─ 否 → 调用云函数 silentLogin
+    │                   │
+    │                   ├─ cloud.getWXContext() 获取 openid/unionid
+    │                   │
+    │                   ├─ 查询 users 集合（openid）
+    │                   │       │
+    │                   │       ├─ 存在 → 更新 lastActiveAt，返回用户数据
+    │                   │       │
+    │                   │       └─ 不存在 → 创建用户（nickName/avatarUrl 为空），返回用户数据
+    │                   │
+    │                   └─ 前端收到用户数据 → 写入内存 + Storage
+    │
+    └─ 完成，进入正常使用
+```
+
+---
+
+## 二、技术细节
+
+### 2.1 云函数：`userLogin`
+
+**职责**：静默登录，upsert 用户记录。
+
+```javascript
+// cloudfunctions/userLogin/index.js
+const cloud = require('wx-server-sdk');
+cloud.init({ env: cloud.DYNAMIC_CURRENT_ENV });
+
+const db = cloud.database();
+
+exports.main = async (event, context) => {
+    const wxContext = cloud.getWXContext();
+    const openid = wxContext.OPENID;
+    const unionid = wxContext.UNIONID || null;
+
+    const usersCollection = db.collection('users');
+
+    // 查询是否已存在
+    const { data } = await usersCollection.where({ openid }).limit(1).get();
+
+    const now = db.serverDate();
+
+    if (data.length > 0) {
+        // 已存在：更新 lastActiveAt 和 unionid（如果有新值）
+        const user = data[0];
+        const updateData = { lastActiveAt: now };
+        if (unionid && !user.unionid) {
+            updateData.unionid = unionid;
+        }
+        await usersCollection.doc(user._id).update({ data: updateData });
+
+        return {
+            code: 0,
+            data: { ...user, ...updateData, lastActiveAt: new Date() },
+        };
+    } else {
+        // 不存在：创建新用户
+        const newUser = {
+            openid,
+            unionid,
+            nickName: null,
+            avatarUrl: null,
+            totalDownloads: 0,
+            createdAt: now,
+            lastActiveAt: now,
+        };
+        const { _id } = await usersCollection.add({ data: newUser });
+
+        return {
+            code: 0,
+            data: {
+                _id,
+                ...newUser,
+                createdAt: new Date(),
+                lastActiveAt: new Date(),
+            },
+        };
+    }
+};
+```
+
+**要点**：
+
+- `cloud.getWXContext()` 在云函数中自动获取调用者的 `OPENID`，无需前端传 code
+- `UNIONID` 仅在小程序绑定了开放平台且满足条件时才有值，所以设为可选
+- 使用 `db.serverDate()` 确保时间由服务端生成，避免客户端时间不准
+- `_id` 由云数据库自动生成（`add()` 时不指定），为随机唯一字符串；业务上通过 `openid` 唯一索引定位用户，`_id` 作为主键供子表（favorites、download_logs）的 `userId` 外键引用
+
+---
+
+### 2.2 前端登录逻辑
+
+**位置**：建议封装为 `miniprogram/utils/auth.ts`
+
+```typescript
+// miniprogram/utils/auth.ts
+
+interface UserInfo {
+    _id: string;
+    openid: string;
+    unionid: string | null;
+    nickName: string | null;
+    avatarUrl: string | null;
+    totalDownloads: number;
+    createdAt: string;
+    lastActiveAt: string;
+}
+
+const STORAGE_KEY = 'user_info';
+const STORAGE_EXPIRE_KEY = 'user_info_expire';
+const EXPIRE_DURATION = 7 * 24 * 60 * 60 * 1000; // 7 天
+
+/** 内存中的用户数据（App 生命周期内有效） */
+let currentUser: UserInfo | null = null;
+
+/**
+ * 获取当前用户，优先内存 → Storage → 云函数登录
+ */
+export async function getUser(): Promise<UserInfo> {
+    // 1. 内存中有，直接返回
+    if (currentUser) return currentUser;
+
+    // 2. 尝试从 Storage 读取
+    const cached = loadFromStorage();
+    if (cached) {
+        currentUser = cached;
+        return cached;
+    }
+
+    // 3. 静默登录
+    return await silentLogin();
+}
+
+/**
+ * 静默登录：调用云函数
+ */
+async function silentLogin(): Promise<UserInfo> {
+    const { result } = await wx.cloud.callFunction({
+        name: 'userLogin',
+    });
+
+    if (result.code !== 0) {
+        throw new Error('登录失败');
+    }
+
+    const user = result.data as UserInfo;
+    currentUser = user;
+    saveToStorage(user);
+    return user;
+}
+
+/**
+ * 从 Storage 读取用户数据（检查过期）
+ */
+function loadFromStorage(): UserInfo | null {
+    try {
+        const expire = wx.getStorageSync(STORAGE_EXPIRE_KEY);
+        if (!expire || Date.now() > expire) {
+            // 已过期，清除
+            wx.removeStorageSync(STORAGE_KEY);
+            wx.removeStorageSync(STORAGE_EXPIRE_KEY);
+            return null;
+        }
+        const user = wx.getStorageSync(STORAGE_KEY);
+        return user || null;
+    } catch {
+        return null;
+    }
+}
+
+/**
+ * 写入 Storage
+ */
+function saveToStorage(user: UserInfo): void {
+    try {
+        wx.setStorageSync(STORAGE_KEY, user);
+        wx.setStorageSync(STORAGE_EXPIRE_KEY, Date.now() + EXPIRE_DURATION);
+    } catch {
+        // Storage 写入失败不影响主流程
+    }
+}
+
+/**
+ * 清除登录状态（用于退出登录或需要强制刷新时）
+ */
+export function clearUser(): void {
+    currentUser = null;
+    wx.removeStorageSync(STORAGE_KEY);
+    wx.removeStorageSync(STORAGE_EXPIRE_KEY);
+}
+
+/**
+ * 强制刷新用户数据（跳过缓存）
+ */
+export async function refreshUser(): Promise<UserInfo> {
+    clearUser();
+    return await silentLogin();
+}
+```
+
+---
+
+### 2.3 调用时机
+
+在 `app.ts` 的 `onLaunch` 中触发登录：
+
+```typescript
+// app.ts
+import { getUser } from './utils/auth';
+
+App({
+    onLaunch() {
+        // 初始化云开发
+        wx.cloud.init({ env: 'your-env-id' });
+
+        // 静默登录（不阻塞页面渲染）
+        getUser().catch((err) => {
+            console.error('静默登录失败', err);
+        });
+    },
+});
+```
+
+**注意**：登录是异步的，不阻塞页面渲染。页面中需要用户数据时通过 `await getUser()` 获取，如果登录已完成会立即返回内存数据。
+
+---
+
+### 2.4 缓存过期策略
+
+| 策略       | 说明                                      |
+| ---------- | ----------------------------------------- |
+| 有效期     | 7 天                                      |
+| 过期后行为 | 下次 `getUser()` 时自动触发静默登录       |
+| 过期目的   | 定期刷新 `lastActiveAt`，保持活跃数据准确 |
+| 强制刷新   | 调用 `refreshUser()` 可随时强制重新登录   |
+
+---
+
+## 三、昵称与头像授权（后续实现）
+
+静默登录不获取用户昵称和头像。当需要展示或使用这些信息时（如个人中心页），引导用户主动填写：
+
+```typescript
+// 使用微信头像昵称填写能力（基础库 2.21.2+）
+// 在 wxml 中使用 <button open-type="chooseAvatar"> 获取头像
+// 使用 <input type="nickname"> 获取昵称
+
+export async function updateProfile(
+    nickName: string,
+    avatarUrl: string,
+): Promise<void> {
+    const { result } = await wx.cloud.callFunction({
+        name: 'userLogin',
+        data: {
+            action: 'updateProfile',
+            nickName,
+            avatarUrl,
+        },
+    });
+
+    if (result.code === 0) {
+        // 更新本地缓存
+        const user = await getUser();
+        user.nickName = nickName;
+        user.avatarUrl = avatarUrl;
+        saveToStorage(user);
+    }
+}
+```
+
+> 注：微信已废弃 `wx.getUserProfile` 和 `wx.getUserInfo` 获取真实用户信息的能力，现在只能通过头像昵称填写组件让用户主动填写。
+
+---
+
+## 四、云函数目录结构
+
+```
+cloudfunctions/
+└── userLogin/
+    ├── index.js          ← 入口，支持 action 路由
+    ├── package.json
+    └── config.json       ← 云函数配置
+```
+
+若后续 `updateProfile` 等操作较多，可在同一个云函数内通过 `event.action` 路由：
+
+```javascript
+exports.main = async (event, context) => {
+    const { action } = event;
+
+    switch (action) {
+        case 'updateProfile':
+            return await handleUpdateProfile(event, context);
+        default:
+            return await handleSilentLogin(event, context);
+    }
+};
+```
+
+---
+
+## 五、安全考虑
+
+| 项目         | 措施                                                      |
+| ------------ | --------------------------------------------------------- |
+| openid 来源  | 仅从 `cloud.getWXContext()` 获取，不信任前端传入          |
+| unionid      | 服务端获取，不暴露给前端                                  |
+| Storage 数据 | 不存储敏感信息（openid 不算高敏感，但也不主动展示给用户） |
+| 接口幂等     | upsert 逻辑天然幂等，重复调用不会创建多条记录             |
+
+---
+
+## 六、与现有架构的关系
+
+- **数据库**：使用 `users` 集合，字段设计见 [小程序云开发方案和数据库设计.md](./小程序云开发方案和数据库设计.md) §3.5
+- **其他云函数**：需要用户身份的云函数（如收藏、下载记录）通过 `cloud.getWXContext().OPENID` 查询 `users` 集合获取 `_id`，作为 `userId` 关联
+- **前端**：各页面通过 `getUser()` 获取用户数据，无需关心登录细节
diff --git a/miniprogram/app.ts b/miniprogram/app.ts
index 4562034..09f6302 100644
--- a/miniprogram/app.ts
+++ b/miniprogram/app.ts
@@ -1,4 +1,5 @@
 import { defaultPrintConfig } from './config/config';
+import { getUser } from './utils/auth';
 import { generateUUID, getAppUUID, setAppUUID } from './utils/uuid';
 
 const STORAGE_KEY_PAGE_CONFIG = 'pageConfig';
@@ -39,6 +40,11 @@ App<IAppOption>({
             this.globalData.printConfig = printConfig;
         }
 
+        // 静默登录（不阻塞页面渲染）
+        getUser().catch((err) => {
+            console.error('静默登录失败', err);
+        });
+
         void this.loadPageConfig();
     },
 
diff --git a/miniprogram/englishPages/letterTracing/letterTracing.ts b/miniprogram/englishPages/letterTracing/letterTracing.ts
index 69960e6..fc86883 100644
--- a/miniprogram/englishPages/letterTracing/letterTracing.ts
+++ b/miniprogram/englishPages/letterTracing/letterTracing.ts
@@ -22,7 +22,7 @@ import {
 } from '../shared/data/fontProfiles';
 import { loadLetterFont } from '../shared/draw/drawTools';
 import type { DebugPublishMeta } from '../../utils/debugPublish';
-import { incrementWorksheetLikes } from '../../utils/worksheetStats';
+import { addFavorite, removeFavorite, batchCheckFavorited } from '../../utils/favorites';
 
 /** 三字母精练分组：26 字母每 3 个一组 */
 const TRIPLE_GROUPS: { title: string; letters: string[] }[] = [];
@@ -82,6 +82,7 @@ createPage(
         boxWidth: 0,
         drawService: null as LetterTracingDraw | null,
         fontProfile: DEFAULT_LETTER_PROFILE as FontProfile,
+        _favoritedMap: {} as Record<string, boolean>,
 
         data: {
             pageTitle: '字母描红',
@@ -147,6 +148,8 @@ createPage(
                     updates as Partial<PageData> & WechatMiniprogram.IAnyObject,
                 );
             }
+
+            this.loadFavoritedMap();
         },
 
         /** 用户点击模式选择器时切换 worksheet */
@@ -275,8 +278,14 @@ createPage(
         async onPreviewFavorite() {
             const next = !this.data.isPreviewFavorite;
             this.setData({ isPreviewFavorite: next });
-            if (next) {
-                incrementWorksheetLikes(this.data.worksheetId);
+            const id = this.data.worksheetId;
+            if (id) {
+                this._favoritedMap[id] = next;
+                if (next) {
+                    addFavorite(id);
+                } else {
+                    removeFavorite(id);
+                }
             }
             wx.showToast({
                 title: next ? '收藏成功' : '已取消收藏',
@@ -284,6 +293,15 @@ createPage(
             });
         },
 
+        async loadFavoritedMap() {
+            const ids = LETTER_TRACING_MODE_OPTIONS.map((d) => d.id);
+            this._favoritedMap = await batchCheckFavorited(ids);
+            const currentId = this.data.worksheetId;
+            if (this._favoritedMap[currentId]) {
+                this.setData({ isPreviewFavorite: true });
+            }
+        },
+
         getPublishMeta(): DebugPublishMeta {
             const meta = getPublishMetaByMode(this.data.worksheetId);
             if (!meta) {
@@ -358,7 +376,7 @@ createPage(
                     worksheetId,
                     functionId: worksheetId,
                     traceMode,
-                    isPreviewFavorite: false,
+                    isPreviewFavorite: !!this._favoritedMap[worksheetId],
                     selectedLetter,
                     selectedLetterPair: `${selectedLetter}${selectedLetter.toLowerCase()}`,
                     letterCaseLower,
diff --git a/miniprogram/focusPages/focusDraw/focusDraw.ts b/miniprogram/focusPages/focusDraw/focusDraw.ts
index 0b05feb..dbbbbfb 100644
--- a/miniprogram/focusPages/focusDraw/focusDraw.ts
+++ b/miniprogram/focusPages/focusDraw/focusDraw.ts
@@ -6,9 +6,9 @@ import {
     type FocusTypeConfig,
     type FocusTypeAction,
 } from './registry';
-import { getPublishMetaByFocusState } from './focusDraw.config';
+import { getPublishMetaByFocusState, FOCUS_WORKSHEET_DEFINITIONS } from './focusDraw.config';
 import type { DebugPublishMeta } from '../../utils/debugPublish';
-import { incrementWorksheetLikes } from '../../utils/worksheetStats';
+import { addFavorite, removeFavorite, batchCheckFavorited } from '../../utils/favorites';
 
 const TYPE_LIST = FOCUS_TYPE_CONFIGS.map((t) => ({
     id: t.id,
@@ -24,6 +24,7 @@ createFocusPage({
     drawService: null as BaseDrawService | null,
     currentTypeConfig: null as FocusTypeConfig | null,
     currentData: null as any,
+    _favoritedMap: {} as Record<string, boolean>,
 
     data: {
         pageTitle: '专注力练习',
@@ -73,6 +74,8 @@ createFocusPage({
         });
 
         this.initPageInfo(routeId, title);
+
+        this.loadFavoritedMap();
     },
 
     onCanvasReady(e: WechatMiniprogram.CustomEvent) {
@@ -121,7 +124,9 @@ createFocusPage({
             selectedTypeId: id,
             functionId: id,
             pageTitle: title,
-            isPreviewFavorite: false,
+            isPreviewFavorite: !!this._favoritedMap[
+                getPublishMetaByFocusState(id, id, mode)?.id || id
+            ],
             showActions: !!typeConfig.actions,
             currentActions: typeConfig.actions || [],
             actionsTitle: typeConfig.actionsTitle || '选择模式',
@@ -158,7 +163,7 @@ createFocusPage({
         this.setData({
             currentMode: value,
             pageTitle: title,
-            isPreviewFavorite: false,
+            isPreviewFavorite: !!this._favoritedMap[this.getWorksheetStatsIdFor(value)],
         });
 
         this.initPageInfo(this.data.functionId, title);
@@ -202,9 +207,14 @@ createFocusPage({
     async onPreviewFavorite() {
         const next = !this.data.isPreviewFavorite;
         this.setData({ isPreviewFavorite: next });
-        if (next) {
-            const id = this.getWorksheetStatsId();
-            if (id) incrementWorksheetLikes(id);
+        const id = this.getWorksheetStatsId();
+        if (id) {
+            this._favoritedMap[id] = next;
+            if (next) {
+                addFavorite(id);
+            } else {
+                removeFavorite(id);
+            }
         }
         wx.showToast({
             title: next ? '收藏成功' : '已取消收藏',
@@ -221,6 +231,24 @@ createFocusPage({
         return meta?.id || this.data.functionId;
     },
 
+    getWorksheetStatsIdFor(mode: string): string {
+        const meta = getPublishMetaByFocusState(
+            this.data.functionId,
+            this.data.selectedTypeId,
+            mode,
+        );
+        return meta?.id || this.data.functionId;
+    },
+
+    async loadFavoritedMap() {
+        const ids = FOCUS_WORKSHEET_DEFINITIONS.map((d) => d.id);
+        this._favoritedMap = await batchCheckFavorited(ids);
+        const currentId = this.getWorksheetStatsId();
+        if (this._favoritedMap[currentId]) {
+            this.setData({ isPreviewFavorite: true });
+        }
+    },
+
     getPublishMeta(): DebugPublishMeta {
         const meta = getPublishMetaByFocusState(
             this.data.functionId,
diff --git a/miniprogram/mathPages/mathDraw/mathDraw.ts b/miniprogram/mathPages/mathDraw/mathDraw.ts
index 675b1de..1a106da 100644
--- a/miniprogram/mathPages/mathDraw/mathDraw.ts
+++ b/miniprogram/mathPages/mathDraw/mathDraw.ts
@@ -6,9 +6,9 @@ import {
     type MathTypeConfig,
     type MathTypeAction,
 } from './registry';
-import { getPublishMetaByMathState } from './mathDraw.config';
+import { getPublishMetaByMathState, MATH_WORKSHEET_DEFINITIONS } from './mathDraw.config';
 import type { DebugPublishMeta } from '../../utils/debugPublish';
-import { incrementWorksheetLikes } from '../../utils/worksheetStats';
+import { addFavorite, removeFavorite, batchCheckFavorited } from '../../utils/favorites';
 
 const TYPE_LIST = MATH_TYPE_CONFIGS.map((t) => ({
     id: t.id,
@@ -25,6 +25,7 @@ createMathPage({
     currentTypeConfig: null as MathTypeConfig | null,
     currentData: null as any,
     routeExtra: null as Record<string, any> | null,
+    _favoritedMap: {} as Record<string, boolean>,
 
     data: {
         pageTitle: '数学练习',
@@ -82,6 +83,9 @@ createMathPage({
         });
 
         this.initPageInfo(routeId, title);
+
+        // 加载收藏状态
+        this.loadFavoritedMap();
     },
 
     onCanvasReady(e: WechatMiniprogram.CustomEvent) {
@@ -131,7 +135,9 @@ createMathPage({
             selectedTypeId: id,
             functionId: id,
             pageTitle: title,
-            isPreviewFavorite: false,
+            isPreviewFavorite: !!this._favoritedMap[
+                getPublishMetaByMathState(id, id, mode)?.id || id
+            ],
             showActions: !!typeConfig.actions,
             currentActions: typeConfig.actions || [],
             actionsTitle: typeConfig.actionsTitle || '选择模式',
@@ -172,7 +178,7 @@ createMathPage({
         this.setData({
             currentMode: value,
             pageTitle: title,
-            isPreviewFavorite: false,
+            isPreviewFavorite: !!this._favoritedMap[this.getWorksheetStatsIdFor(value)],
         });
 
         this.initPageInfo(this.data.functionId, title);
@@ -266,9 +272,14 @@ createMathPage({
     async onPreviewFavorite() {
         const next = !this.data.isPreviewFavorite;
         this.setData({ isPreviewFavorite: next });
-        if (next) {
-            const id = this.getWorksheetStatsId();
-            if (id) incrementWorksheetLikes(id);
+        const id = this.getWorksheetStatsId();
+        if (id) {
+            this._favoritedMap[id] = next;
+            if (next) {
+                addFavorite(id);
+            } else {
+                removeFavorite(id);
+            }
         }
         wx.showToast({
             title: next ? '收藏成功' : '已取消收藏',
@@ -285,6 +296,25 @@ createMathPage({
         return meta?.id || this.data.functionId;
     },
 
+    getWorksheetStatsIdFor(mode: string): string {
+        const meta = getPublishMetaByMathState(
+            this.data.functionId,
+            this.data.selectedTypeId,
+            mode,
+        );
+        return meta?.id || this.data.functionId;
+    },
+
+    async loadFavoritedMap() {
+        const ids = MATH_WORKSHEET_DEFINITIONS.map((d) => d.id);
+        this._favoritedMap = await batchCheckFavorited(ids);
+        // 回显当前选中的收藏状态
+        const currentId = this.getWorksheetStatsId();
+        if (this._favoritedMap[currentId]) {
+            this.setData({ isPreviewFavorite: true });
+        }
+    },
+
     getPublishMeta(): DebugPublishMeta {
         const meta = getPublishMetaByMathState(
             this.data.functionId,
diff --git a/miniprogram/pages/favorites/favorites.ts b/miniprogram/pages/favorites/favorites.ts
index 822eecf..6766fbe 100644
--- a/miniprogram/pages/favorites/favorites.ts
+++ b/miniprogram/pages/favorites/favorites.ts
@@ -1,27 +1,24 @@
 import { NAV_INNER_PX } from '../../utils/navMetrics';
+import { getFavoriteList, removeFavorite } from '../../utils/favorites';
+import { getDownloadLogs } from '../../utils/downloadLogs';
+import type { FavoriteRecord } from '../../utils/favorites';
+import type { DownloadLogRecord } from '../../utils/downloadLogs';
 
 const { statusBarHeight } = wx.getWindowInfo();
 const NAV_BLOCK_HEIGHT = statusBarHeight + NAV_INNER_PX;
 
 type FavoritesTab = 'favorites' | 'downloads';
 
-type FavoriteItem =
-    | {
-          id: string;
-          variant: 'standard';
-          title: string;
-          metaLine: string;
-          stars: number;
-          timeBadge: string;
-          thumb: string;
-      }
-    | {
-          id: string;
-          variant: 'featured';
-          title: string;
-          metaLine: string;
-          tags: string[];
-      };
+type FavoriteItem = {
+    id: string;
+    worksheetId: string;
+    variant: 'standard';
+    title: string;
+    metaLine: string;
+    stars: number;
+    timeBadge: string;
+    thumb: string;
+};
 
 type DownloadRow = {
     id: string;
@@ -39,88 +36,94 @@ type DownloadSection = {
     items: DownloadRow[];
 };
 
-const MOCK_FAVORITES: FavoriteItem[] = [
-    {
-        id: '1',
-        variant: 'standard',
-        title: '10以内加法',
-        metaLine: '数学启蒙 · 4-6岁 · ',
-        stars: 2,
-        timeBadge: '收藏于 3 天前',
-        thumb: 'https://lh3.googleusercontent.com/aida-public/AB6AXuD7khp0rJABfa9yFrMt9ZgIhAPyN44XmJ2pXNBgCzbgBvwA5ptFZVty013JedVzbE9_VvCQnToN7QETLDKjtiX22igzK-a5h4E8wjKrembFW4eVuk1RsJIbHjx3_cCz0hJ7_t76hF8t-Qdod_5R9sNMor1ZEjf6dGNp6UI_eIBjsN9b22iCTJ2VB-IEh0Rmil6_iC4Og-4I03IcQDV2rTHYIXcZxjiay1IiYGXw3wJ3bfo2SF2N7ZFT00akTgYU-9JyF7xJ6n15Yzc',
-    },
-    {
-        id: '2',
-        variant: 'standard',
-        title: '图形连连看',
-        metaLine: '逻辑思维 · 3-5岁 · ',
-        stars: 1,
-        timeBadge: '收藏于 5 天前',
-        thumb: 'https://lh3.googleusercontent.com/aida-public/AB6AXuBY_0Rr153ZBT4IHcMyFtrcgl-y2ZRyVnOuGecnn7f4PZKoAx2lOuCorsMmfRa72s0JmbXrt4XT3QU1x7cIbZUyhv_EXwCfMaNxtkHc-ymIBIQ5jqm5oiQebrEWH4kjv14JdkCiziT4xzac4TdVN5yqpk7Wlg80QBl_ldDmAQqIgcUeN2PvlVvhmpOYmFeWE2HS3I_e4vV1J8s_cfV9_4g7y8SbxlSfnTmgQNeXrVbcdwaNEAGQWp92Iif0d2pVIqdfuUHO1pTw8oQ',
-    },
-    {
-        id: '3',
-        variant: 'standard',
-        title: '拼音字母认读',
-        metaLine: '语文基础 · 5-7岁 · ',
-        stars: 3,
-        timeBadge: '收藏于 1 周前',
-        thumb: 'https://lh3.googleusercontent.com/aida-public/AB6AXuC54mXQ8620XwIsWmUHBHJGdmpF8uE4cSYxwR2NLJTsa6gYdTCHz2tqrKbGOye-y0CGgCPPWwJXzEuB2ZYrQ3CWWPlamvbjhTUDYf8yoA9Lyapll1t2w17AqzSHrbBPNFrq931IUCis64b51kslQZoq3c0KslZsBQiky-YSnuE7xUuNsgiF4hOak_ReFFufWE53h1sPkjHFeRM-H34b-e1MCNxGObGPhI0mNlJ_qz0c8aCuS-jdnDocSvIYda-iVcJLWcIT-mO6klw',
-    },
-    {
-        id: '4',
-        variant: 'featured',
-        title: '趣味英语单词卡',
-        metaLine: '语言学习 · 4-8岁 · ⭐⭐⭐',
-        tags: ['畅销经典', '全彩打印'],
-    },
-];
+function mapFavoriteToItem(record: FavoriteRecord): FavoriteItem {
+    const ws = record.worksheet;
+    const title = ws?.title || '未知题型';
+    const category = ws?.category || '';
+    const ageRange = ws ? `${ws.ageMin}-${ws.ageMax}岁` : '';
+    const metaLine = [category, ageRange].filter(Boolean).join(' · ') + ' · ';
+    const difficulty = ws?.difficulty || 0;
+    const timeBadge = formatTimeBadge(record.createdAt);
 
-const MOCK_DOWNLOADS: DownloadSection[] = [
-    {
-        key: 'today',
-        label: '今天',
-        items: [
-            {
-                id: 'd1',
-                title: '拼音描红 · 声母表',
-                time: '14:32',
-                status: '已保存相册',
-                statusHighlight: true,
-                thumb: 'https://lh3.googleusercontent.com/aida-public/AB6AXuBCm6X4rhibw2_WxP-U0dDyOsiYol3y12OnEXHRkPONZYMQBUcr3Grqo1IbwH3sdWPg5jIUeIbr_AEwv_hFwUOMMz9jTIIMc6Pke1bzSvlQcgdDq-zMEIU4A--IQFX59ac-8BscCajXZcd4v8rE6JEZFf1-aztKclPTkE_Rrgj-nbVCy5V6bOE6yDOB67VdTbcqiOdaFN18ju_MgWVo3FQZLwIUZOBahkPl0vDIKA0mkiaGK9eiFpfnERYxkYG3eWJZ40umTYp46Jo',
-            },
-            {
-                id: 'd2',
-                title: '趣味口算题卡',
-                time: '09:15',
-                status: '已下载 PDF',
-                statusHighlight: false,
-                thumb: 'https://lh3.googleusercontent.com/aida-public/AB6AXuBxNORxN_vftYMLaMjZVscL-o9bZnBrfUi7IAqOrFATIztGV12_0ggwgae-fmk0cORWtysZWJJDcAzj0NEyniFxbREoGDuq9U4kytprJkA70_k0MCzPgStmq0bRwu1Gx1j4peglFam8PH6IlPvOMbiHQ7-fMFfYTSBtA1p7Dp06NDOzS2VrMlF8VxjEgihVmhHUrHePVvXlktUkXBKNzrXEXrogO3iOyouTUKyvJh0TeChKUv3KohMoD5ol7C3fjBhdHf7QD4StOQ4',
-            },
-        ],
-    },
-    {
-        key: 'yesterday',
-        label: '昨天',
-        items: [
-            {
-                id: 'd3',
-                title: '汉字笔画基础训练',
-                time: '16:40',
-                status: '已发送邮件',
-                statusHighlight: false,
-                placeholder: 'draw',
-            },
-        ],
-    },
-];
+    return {
+        id: record._id,
+        worksheetId: record.worksheetId,
+        variant: 'standard',
+        title,
+        metaLine,
+        stars: Math.min(difficulty, 3),
+        timeBadge,
+        thumb: ws?.previewImg || '',
+    };
+}
+
+function formatTimeBadge(dateStr: string): string {
+    const date = new Date(dateStr);
+    const now = new Date();
+    const diff = now.getTime() - date.getTime();
+    const days = Math.floor(diff / (1000 * 60 * 60 * 24));
+
+    if (days === 0) return '收藏于今天';
+    if (days === 1) return '收藏于昨天';
+    if (days < 7) return `收藏于 ${days} 天前`;
+    if (days < 30) return `收藏于 ${Math.floor(days / 7)} 周前`;
+    return `收藏于 ${Math.floor(days / 30)} 个月前`;
+}
+
+function groupDownloadsByDate(records: DownloadLogRecord[]): DownloadSection[] {
+    const now = new Date();
+    const todayStr = formatDateKey(now);
+    const yesterday = new Date(now.getTime() - 24 * 60 * 60 * 1000);
+    const yesterdayStr = formatDateKey(yesterday);
+
+    const groups: Record<string, { label: string; items: DownloadRow[] }> = {};
+
+    for (const record of records) {
+        const date = new Date(record.createdAt);
+        const key = formatDateKey(date);
+        let label: string;
+
+        if (key === todayStr) {
+            label = '今天';
+        } else if (key === yesterdayStr) {
+            label = '昨天';
+        } else {
+            label = `${date.getMonth() + 1}月${date.getDate()}日`;
+        }
+
+        if (!groups[key]) {
+            groups[key] = { label, items: [] };
+        }
+
+        const ws = record.worksheet;
+        groups[key].items.push({
+            id: record._id,
+            title: ws?.title || '未知题型',
+            time: `${String(date.getHours()).padStart(2, '0')}:${String(date.getMinutes()).padStart(2, '0')}`,
+            status: '已保存相册',
+            statusHighlight: true,
+            thumb: ws?.previewImg,
+        });
+    }
+
+    return Object.keys(groups).map((key) => ({
+        key,
+        label: groups[key].label,
+        items: groups[key].items,
+    }));
+}
+
+function formatDateKey(date: Date): string {
+    return `${date.getFullYear()}-${date.getMonth() + 1}-${date.getDate()}`;
+}
 
 Page({
     data: {
         favScrollHeight: 0,
         activeTab: 'favorites' as FavoritesTab,
-        favoriteList: MOCK_FAVORITES as FavoriteItem[],
-        downloadSections: MOCK_DOWNLOADS as DownloadSection[],
+        favoriteList: [] as FavoriteItem[],
+        downloadSections: [] as DownloadSection[],
+        loading: false,
     },
 
     onLoad() {
@@ -136,6 +139,7 @@ Page({
             this.setData({ activeTab: tab });
             wx.removeStorageSync('favorites_active_tab');
         }
+        this.loadData();
     },
 
     onTabSwitch(e: WechatMiniprogram.TouchEvent) {
@@ -144,6 +148,24 @@ Page({
         this.setData({ activeTab: tab });
     },
 
+    async loadData() {
+        this.setData({ loading: true });
+        await Promise.all([this.loadFavorites(), this.loadDownloads()]);
+        this.setData({ loading: false });
+    },
+
+    async loadFavorites() {
+        const records = await getFavoriteList();
+        const list = records.map((r) => mapFavoriteToItem(r));
+        this.setData({ favoriteList: list });
+    },
+
+    async loadDownloads() {
+        const records = await getDownloadLogs();
+        const sections = groupDownloadsByDate(records);
+        this.setData({ downloadSections: sections });
+    },
+
     onDiscoverTap() {
         wx.switchTab({ url: '/pages/home/home' });
     },
@@ -152,12 +174,24 @@ Page({
         wx.showToast({ title: '搜索功能开发中', icon: 'none' });
     },
 
-    onRemoveFavorite(e: WechatMiniprogram.TouchEvent) {
+    async onRemoveFavorite(e: WechatMiniprogram.TouchEvent) {
         const id = e.currentTarget.dataset.id as string | undefined;
         if (!id) return;
-        const list = (this.data.favoriteList as FavoriteItem[]).filter((item) => item.id !== id);
+
+        const item = (this.data.favoriteList as FavoriteItem[]).find(
+            (i) => i.id === id,
+        );
+        if (!item) return;
+
+        // 乐观更新 UI
+        const list = (this.data.favoriteList as FavoriteItem[]).filter(
+            (i) => i.id !== id,
+        );
         this.setData({ favoriteList: list });
         wx.showToast({ title: '已取消收藏', icon: 'none' });
+
+        // 调用云端
+        await removeFavorite(item.worksheetId);
     },
 
     onClearHistory() {
@@ -174,6 +208,9 @@ Page({
 
     onDownloadMore(e: WechatMiniprogram.TouchEvent) {
         const id = e.currentTarget.dataset.id as string | undefined;
-        wx.showToast({ title: id ? `更多操作：${id}` : '更多', icon: 'none' });
+        wx.showToast({
+            title: id ? `更多操作：${id}` : '更多',
+            icon: 'none',
+        });
     },
 });
diff --git a/miniprogram/utils/auth.ts b/miniprogram/utils/auth.ts
new file mode 100644
index 0000000..5eed2b0
--- /dev/null
+++ b/miniprogram/utils/auth.ts
@@ -0,0 +1,111 @@
+interface UserInfo {
+    _id: string;
+    openid: string;
+    unionid: string | null;
+    nickName: string | null;
+    avatarUrl: string | null;
+    totalDownloads: number;
+    createdAt: string;
+    lastActiveAt: string;
+}
+
+const STORAGE_KEY = 'user_info';
+const STORAGE_EXPIRE_KEY = 'user_info_expire';
+const EXPIRE_DURATION = 7 * 24 * 60 * 60 * 1000; // 7 天
+
+/** 内存中的用户数据（App 生命周期内有效） */
+let currentUser: UserInfo | null = null;
+
+/** 登录进行中的 Promise（防止并发重复调用） */
+let loginPromise: Promise<UserInfo> | null = null;
+
+/**
+ * 获取当前用户，优先内存 → Storage → 云函数登录
+ */
+export async function getUser(): Promise<UserInfo> {
+    // 1. 内存中有，直接返回
+    if (currentUser) return currentUser;
+
+    // 2. 尝试从 Storage 读取
+    const cached = loadFromStorage();
+    if (cached) {
+        currentUser = cached;
+        return cached;
+    }
+
+    // 3. 静默登录（防止并发）
+    if (!loginPromise) {
+        loginPromise = silentLogin().finally(() => {
+            loginPromise = null;
+        });
+    }
+    return loginPromise;
+}
+
+/**
+ * 静默登录：调用云函数
+ */
+async function silentLogin(): Promise<UserInfo> {
+    const res = await wx.cloud.callFunction({
+        name: 'userLogin',
+    });
+    const result = (res?.result as any) || {};
+
+    if (result.code !== 0) {
+        throw new Error('登录失败');
+    }
+
+    const user = result.data as UserInfo;
+    currentUser = user;
+    saveToStorage(user);
+    return user;
+}
+
+/**
+ * 从 Storage 读取用户数据（检查过期）
+ */
+function loadFromStorage(): UserInfo | null {
+    try {
+        const expire = wx.getStorageSync(STORAGE_EXPIRE_KEY);
+        if (!expire || Date.now() > expire) {
+            wx.removeStorageSync(STORAGE_KEY);
+            wx.removeStorageSync(STORAGE_EXPIRE_KEY);
+            return null;
+        }
+        const user = wx.getStorageSync(STORAGE_KEY);
+        return user || null;
+    } catch {
+        return null;
+    }
+}
+
+/**
+ * 写入 Storage
+ */
+function saveToStorage(user: UserInfo): void {
+    try {
+        wx.setStorageSync(STORAGE_KEY, user);
+        wx.setStorageSync(STORAGE_EXPIRE_KEY, Date.now() + EXPIRE_DURATION);
+    } catch {
+        // Storage 写入失败不影响主流程
+    }
+}
+
+/**
+ * 清除登录状态
+ */
+export function clearUser(): void {
+    currentUser = null;
+    wx.removeStorageSync(STORAGE_KEY);
+    wx.removeStorageSync(STORAGE_EXPIRE_KEY);
+}
+
+/**
+ * 强制刷新用户数据（跳过缓存）
+ */
+export async function refreshUser(): Promise<UserInfo> {
+    clearUser();
+    return await silentLogin();
+}
+
+export type { UserInfo };
diff --git a/miniprogram/utils/downloadLogs.ts b/miniprogram/utils/downloadLogs.ts
new file mode 100644
index 0000000..7744e85
--- /dev/null
+++ b/miniprogram/utils/downloadLogs.ts
@@ -0,0 +1,56 @@
+import { getUser } from './auth';
+
+export interface DownloadLogRecord {
+    _id: string;
+    userId: string;
+    worksheetId: string;
+    createdAt: string;
+    worksheet?: {
+        _id: string;
+        title: string;
+        subtitle: string;
+        category: string;
+        subcategory: string;
+        previewImg: string;
+    } | null;
+}
+
+/**
+ * 记录下载日志
+ */
+export async function addDownloadLog(worksheetId: string): Promise<boolean> {
+    if (!worksheetId) return false;
+    try {
+        await getUser();
+        const res = await wx.cloud.callFunction({
+            name: 'userDownloadLogs',
+            data: { action: 'add', worksheetId },
+        });
+        const result = (res?.result as any) || {};
+        return result.code === 0;
+    } catch (e) {
+        console.error('addDownloadLog failed', e);
+        return false;
+    }
+}
+
+/**
+ * 获取下载历史
+ */
+export async function getDownloadLogs(
+    page = 1,
+    pageSize = 20,
+): Promise<DownloadLogRecord[]> {
+    try {
+        await getUser();
+        const res = await wx.cloud.callFunction({
+            name: 'userDownloadLogs',
+            data: { action: 'list', page, pageSize },
+        });
+        const result = (res?.result as any) || {};
+        return result.code === 0 ? result.data : [];
+    } catch (e) {
+        console.error('getDownloadLogs failed', e);
+        return [];
+    }
+}
diff --git a/miniprogram/utils/downloadPrint.ts b/miniprogram/utils/downloadPrint.ts
index a0b3575..f0af73c 100644
--- a/miniprogram/utils/downloadPrint.ts
+++ b/miniprogram/utils/downloadPrint.ts
@@ -5,7 +5,7 @@
 
 import { checkAndSaveImage } from './saveImage';
 import tracker from './tracker';
-import { incrementWorksheetDownloads } from './worksheetStats';
+import { addDownloadLog } from './downloadLogs';
 
 // 存储键名
 const STORAGE_KEY_DOWNLOAD_COUNT = 'downloadCount';
@@ -212,7 +212,7 @@ function doDownload(
         if (saved) {
             incrementDownloadCount();
             if (options.worksheetId) {
-                incrementWorksheetDownloads(options.worksheetId);
+                addDownloadLog(options.worksheetId);
             }
         }
         return saved;
diff --git a/miniprogram/utils/favorites.ts b/miniprogram/utils/favorites.ts
new file mode 100644
index 0000000..4605d52
--- /dev/null
+++ b/miniprogram/utils/favorites.ts
@@ -0,0 +1,116 @@
+import { getUser } from './auth';
+
+export interface FavoriteRecord {
+    _id: string;
+    userId: string;
+    worksheetId: string;
+    createdAt: string;
+    worksheet?: {
+        _id: string;
+        title: string;
+        subtitle: string;
+        category: string;
+        subcategory: string;
+        ageMin: number;
+        ageMax: number;
+        difficulty: number;
+        previewImg: string;
+        tags: string[];
+    } | null;
+}
+
+/**
+ * 添加收藏
+ */
+export async function addFavorite(worksheetId: string): Promise<boolean> {
+    try {
+        await getUser(); // 确保已登录
+        const res = await wx.cloud.callFunction({
+            name: 'userFavorites',
+            data: { action: 'add', worksheetId },
+        });
+        const result = (res?.result as any) || {};
+        return result.code === 0;
+    } catch (e) {
+        console.error('addFavorite failed', e);
+        return false;
+    }
+}
+
+/**
+ * 取消收藏
+ */
+export async function removeFavorite(worksheetId: string): Promise<boolean> {
+    try {
+        await getUser();
+        const res = await wx.cloud.callFunction({
+            name: 'userFavorites',
+            data: { action: 'remove', worksheetId },
+        });
+        const result = (res?.result as any) || {};
+        return result.code === 0;
+    } catch (e) {
+        console.error('removeFavorite failed', e);
+        return false;
+    }
+}
+
+/**
+ * 获取收藏列表
+ */
+export async function getFavoriteList(
+    page = 1,
+    pageSize = 20,
+): Promise<FavoriteRecord[]> {
+    try {
+        await getUser();
+        const res = await wx.cloud.callFunction({
+            name: 'userFavorites',
+            data: { action: 'list', page, pageSize },
+        });
+        const result = (res?.result as any) || {};
+        return result.code === 0 ? result.data : [];
+    } catch (e) {
+        console.error('getFavoriteList failed', e);
+        return [];
+    }
+}
+
+/**
+ * 检查是否已收藏
+ */
+export async function checkFavorited(worksheetId: string): Promise<boolean> {
+    try {
+        await getUser();
+        const res = await wx.cloud.callFunction({
+            name: 'userFavorites',
+            data: { action: 'check', worksheetId },
+        });
+        const result = (res?.result as any) || {};
+        return result.code === 0 && result.data?.favorited;
+    } catch (e) {
+        console.error('checkFavorited failed', e);
+        return false;
+    }
+}
+
+/**
+ * 批量检查是否已收藏，返回 { worksheetId: true } 的 map
+ */
+export async function batchCheckFavorited(
+    worksheetIds: string[],
+): Promise<Record<string, boolean>> {
+    if (!worksheetIds.length) return {};
+    try {
+        await getUser();
+        const res = await wx.cloud.callFunction({
+            name: 'userFavorites',
+            data: { action: 'batchCheck', worksheetIds },
+        });
+        const result = (res?.result as any) || {};
+        return result.code === 0 ? result.data : {};
+    } catch (e) {
+        console.error('batchCheckFavorited failed', e);
+        return {};
+    }
+}