feat(privacy): add user privacy settings and account deletion system

Add privacy settings allowing users to control visibility of their followers, following, posts, and favorites lists with three visibility levels: everyone, following, and self. Also implement account deletion workflow with 30-day cooldown period.

- Add PrivacySettings model with visibility levels
- Add DTOs for privacy settings and account deletion
- Add repository methods for privacy settings and deletion
- Add service methods to check visibility permissions
- Add handlers for get/update privacy settings and account deletion
- Add new routes for privacy settings and account management
- Add account cleanup service for hard-deleting expired accounts
- Modify login to cancel deletion when user logs in

BREAKING CHANGE: Users with pending_deletion status can no longer log in; logging in now automatically cancels deletion requests.

internal/dto/dto.go

@@ -44,6 +44,8 @@ type UserSelfResponse struct {
 	FollowingCount int     `json:"following_count"`
 	IsVerified     bool    `json:"is_verified"`
 	CreatedAt      string  `json:"created_at"`
+	// 隐私设置
+	PrivacySettings *PrivacySettingsResponse `json:"privacy_settings,omitempty"`
 }
 
 // UserDetailResponse 用户详情响应（仅本人可见，包含敏感信息）
@@ -66,6 +68,8 @@ type UserDetailResponse struct {
 	IsFollowing    bool    `json:"is_following"`
 	IsFollowingMe  bool    `json:"is_following_me"`
 	CreatedAt      string  `json:"created_at"`
+	// 隐私设置
+	PrivacySettings *PrivacySettingsResponse `json:"privacy_settings,omitempty"`
 }
 
 // ==================== Admin User DTOs ====================
@@ -1403,3 +1407,33 @@ type AdminReviewVerificationRequest struct {
 	Approve      bool   `json:"approve" binding:"required"`
 	RejectReason string `json:"reject_reason" binding:"omitempty,max=500"`
 }
+
+// ==================== Privacy & Account Deletion DTOs ====================
+
+// PrivacySettingsRequest 隐私设置请求
+type PrivacySettingsRequest struct {
+	FollowersVisibility *string `json:"followers_visibility" binding:"omitempty,oneof=everyone following self"`
+	FollowingVisibility *string `json:"following_visibility" binding:"omitempty,oneof=everyone following self"`
+	PostsVisibility     *string `json:"posts_visibility" binding:"omitempty,oneof=everyone following self"`
+	FavoritesVisibility *string `json:"favorites_visibility" binding:"omitempty,oneof=everyone following self"`
+}
+
+// PrivacySettingsResponse 隐私设置响应
+type PrivacySettingsResponse struct {
+	FollowersVisibility string `json:"followers_visibility"`
+	FollowingVisibility string `json:"following_visibility"`
+	PostsVisibility     string `json:"posts_visibility"`
+	FavoritesVisibility string `json:"favorites_visibility"`
+}
+
+// RequestDeletionRequest 申请注销请求
+type RequestDeletionRequest struct {
+	Password string `json:"password" binding:"required"`
+}
+
+// DeletionStatusResponse 注销状态响应
+type DeletionStatusResponse struct {
+	IsPendingDeletion   bool   `json:"is_pending_deletion"`
+	DeletionRequestedAt string `json:"deletion_requested_at,omitempty"`
+	CoolDownDays        int    `json:"cool_down_days,omitempty"`
+}

internal/dto/user_converter.go

@@ -40,22 +40,35 @@ func ConvertUserToSelfResponse(user *model.User, postsCount int) *UserSelfRespon
 		return nil
 	}
 	return &UserSelfResponse{
-		ID:             user.ID,
+		ID:              user.ID,
-		Username:       user.Username,
+		Username:        user.Username,
-		Nickname:       user.Nickname,
+		Nickname:        user.Nickname,
-		Email:          user.Email,
+		Email:           user.Email,
-		Phone:          user.Phone,
+		Phone:           user.Phone,
-		EmailVerified:  user.EmailVerified,
+		EmailVerified:   user.EmailVerified,
-		Avatar:         getAvatarOrDefault(user),
+		Avatar:          getAvatarOrDefault(user),
-		CoverURL:       user.CoverURL,
+		CoverURL:        user.CoverURL,
-		Bio:            user.Bio,
+		Bio:             user.Bio,
-		Website:        user.Website,
+		Website:         user.Website,
-		Location:       user.Location,
+		Location:        user.Location,
-		PostsCount:     postsCount,
+		PostsCount:      postsCount,
-		FollowersCount: user.FollowersCount,
+		FollowersCount:  user.FollowersCount,
-		FollowingCount: user.FollowingCount,
+		FollowingCount:  user.FollowingCount,
-		IsVerified:     user.IsVerified,
+		IsVerified:      user.IsVerified,
-		CreatedAt:      FormatTime(user.CreatedAt),
+		CreatedAt:       FormatTime(user.CreatedAt),
+		PrivacySettings: convertPrivacySettingsToResponse(&user.PrivacySettings),
+	}
+}
+
+func convertPrivacySettingsToResponse(ps *model.PrivacySettings) *PrivacySettingsResponse {
+	if ps == nil {
+		return nil
+	}
+	return &PrivacySettingsResponse{
+		FollowersVisibility: string(ps.FollowersVisibility),
+		FollowingVisibility: string(ps.FollowingVisibility),
+		PostsVisibility:     string(ps.PostsVisibility),
+		FavoritesVisibility: string(ps.FavoritesVisibility),
 	}
 }
 
@@ -159,21 +172,22 @@ func ConvertUserToDetailResponse(user *model.User) *UserDetailResponse {
 		return nil
 	}
 	return &UserDetailResponse{
-		ID:             user.ID,
+		ID:              user.ID,
-		Username:       user.Username,
+		Username:        user.Username,
-		Nickname:       user.Nickname,
+		Nickname:        user.Nickname,
-		Email:          user.Email,
+		Email:           user.Email,
-		EmailVerified:  user.EmailVerified,
+		EmailVerified:   user.EmailVerified,
-		Avatar:         getAvatarOrDefault(user),
+		Avatar:          getAvatarOrDefault(user),
-		CoverURL:       user.CoverURL,
+		CoverURL:        user.CoverURL,
-		Bio:            user.Bio,
+		Bio:             user.Bio,
-		Website:        user.Website,
+		Website:         user.Website,
-		Location:       user.Location,
+		Location:        user.Location,
-		PostsCount:     user.PostsCount,
+		PostsCount:      user.PostsCount,
-		FollowersCount: user.FollowersCount,
+		FollowersCount:  user.FollowersCount,
-		FollowingCount: user.FollowingCount,
+		FollowingCount:  user.FollowingCount,
-		IsVerified:     user.IsVerified,
+		IsVerified:      user.IsVerified,
-		CreatedAt:      FormatTime(user.CreatedAt),
+		CreatedAt:       FormatTime(user.CreatedAt),
+		PrivacySettings: convertPrivacySettingsToResponse(&user.PrivacySettings),
 	}
 }
 
@@ -183,22 +197,23 @@ func ConvertUserToDetailResponseWithPostsCount(user *model.User, postsCount int)
 		return nil
 	}
 	return &UserDetailResponse{
-		ID:             user.ID,
+		ID:              user.ID,
-		Username:       user.Username,
+		Username:        user.Username,
-		Nickname:       user.Nickname,
+		Nickname:        user.Nickname,
-		Email:          user.Email,
+		Email:           user.Email,
-		EmailVerified:  user.EmailVerified,
+		EmailVerified:   user.EmailVerified,
-		Phone:          user.Phone,
+		Phone:           user.Phone,
-		Avatar:         getAvatarOrDefault(user),
+		Avatar:          getAvatarOrDefault(user),
-		CoverURL:       user.CoverURL,
+		CoverURL:        user.CoverURL,
-		Bio:            user.Bio,
+		Bio:             user.Bio,
-		Website:        user.Website,
+		Website:         user.Website,
-		Location:       user.Location,
+		Location:        user.Location,
-		PostsCount:     postsCount,
+		PostsCount:      postsCount,
-		FollowersCount: user.FollowersCount,
+		FollowersCount:  user.FollowersCount,
-		FollowingCount: user.FollowingCount,
+		FollowingCount:  user.FollowingCount,
-		IsVerified:     user.IsVerified,
+		IsVerified:      user.IsVerified,
-		CreatedAt:      FormatTime(user.CreatedAt),
+		CreatedAt:       FormatTime(user.CreatedAt),
+		PrivacySettings: convertPrivacySettingsToResponse(&user.PrivacySettings),
 	}
 }
 

internal/handler/post_handler.go

@@ -17,9 +17,9 @@ import (
 
 // PostHandler 帖子处理器
 type PostHandler struct {
-	postService     service.PostService
+	postService    service.PostService
-	userService     service.UserService
+	userService    service.UserService
-	channelService  service.ChannelService
+	channelService service.ChannelService
 }
 
 // NewPostHandler 创建帖子处理器
@@ -116,27 +116,27 @@ func (h *PostHandler) GetByID(c *gin.Context) {
 
 	// 构建响应
 	responseData := &dto.PostResponse{
-		ID:             post.ID,
+		ID:              post.ID,
-		UserID:         post.UserID,
+		UserID:          post.UserID,
-		ChannelID:      post.ChannelID,
+		ChannelID:       post.ChannelID,
-		Title:          post.Title,
+		Title:           post.Title,
-		Content:        post.Content,
+		Content:         post.Content,
-		Images:         dto.ConvertPostImagesToResponse(post.Images),
+		Images:          dto.ConvertPostImagesToResponse(post.Images),
-		Status:         string(post.Status),
+		Status:          string(post.Status),
-		LikesCount:     post.LikesCount,
+		LikesCount:      post.LikesCount,
-		CommentsCount:  post.CommentsCount,
+		CommentsCount:   post.CommentsCount,
-		FavoritesCount: post.FavoritesCount,
+		FavoritesCount:  post.FavoritesCount,
-		SharesCount:    post.SharesCount,
+		SharesCount:     post.SharesCount,
-		ViewsCount:     post.ViewsCount,
+		ViewsCount:      post.ViewsCount,
-		IsPinned:       post.IsPinned,
+		IsPinned:        post.IsPinned,
-		IsLocked:       post.IsLocked,
+		IsLocked:        post.IsLocked,
-		IsVote:         post.IsVote,
+		IsVote:          post.IsVote,
 		CreatedAt:       dto.FormatTime(post.CreatedAt),
 		UpdatedAt:       dto.FormatTime(post.UpdatedAt),
 		ContentEditedAt: dto.FormatTimePointer(post.ContentEditedAt),
 		Author:          authorWithFollowStatus,
-		IsLiked:        isLiked,
+		IsLiked:         isLiked,
-		IsFavorited:    isFavorited,
+		IsFavorited:     isFavorited,
 	}
 
 	chMap := h.channelMapForPosts([]*model.Post{post})
@@ -553,6 +553,19 @@ func (h *PostHandler) Unfavorite(c *gin.Context) {
 
 // GetUserPosts 获取用户帖子列表（支持游标分页和偏移分页）
 func (h *PostHandler) GetUserPosts(c *gin.Context) {
+	userID := c.Param("id")
+	currentUserID := c.GetString("user_id")
+
+	canView, err := h.userService.CanViewPosts(c.Request.Context(), currentUserID, userID)
+	if err != nil {
+		response.InternalServerError(c, "failed to check privacy settings")
+		return
+	}
+	if !canView {
+		response.Forbidden(c, "该用户的帖子列表不对外公开")
+		return
+	}
+
 	// 检查是否使用游标分页
 	cursorStr := c.Query("cursor")
 	if cursorStr != "" {
@@ -561,12 +574,10 @@ func (h *PostHandler) GetUserPosts(c *gin.Context) {
 	}
 
 	// 偏移分页（向后兼容）
-	userID := c.Param("id")
 	page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
 	pageSize, _ := strconv.Atoi(c.DefaultQuery("page_size", "20"))
 	page, pageSize = normalizePagination(page, pageSize)
 
-	currentUserID := c.GetString("user_id")
 	includePending := currentUserID != "" && currentUserID == userID
 	posts, total, err := h.postService.GetUserPosts(c.Request.Context(), userID, page, pageSize, includePending)
 	if err != nil {
@@ -629,6 +640,18 @@ func (h *PostHandler) GetUserPostsByCursor(c *gin.Context) {
 // GetFavorites 获取收藏列表
 func (h *PostHandler) GetFavorites(c *gin.Context) {
 	userID := c.Param("id")
+	currentUserID := c.GetString("user_id")
+
+	canView, err := h.userService.CanViewFavorites(c.Request.Context(), currentUserID, userID)
+	if err != nil {
+		response.InternalServerError(c, "failed to check privacy settings")
+		return
+	}
+	if !canView {
+		response.Forbidden(c, "该用户的收藏列表不对外公开")
+		return
+	}
+
 	page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
 	pageSize, _ := strconv.Atoi(c.DefaultQuery("page_size", "20"))
 	page, pageSize = normalizePagination(page, pageSize)
@@ -639,8 +662,6 @@ func (h *PostHandler) GetFavorites(c *gin.Context) {
 		return
 	}
 
-	// 批量获取交互状态
-	currentUserID := c.GetString("user_id")
 	postIDs := make([]string, len(posts))
 	for i, post := range posts {
 		postIDs[i] = post.ID

internal/handler/user_handler.go

@@ -615,6 +615,17 @@ func (h *UserHandler) GetBlockStatus(c *gin.Context) {
 func (h *UserHandler) GetFollowingList(c *gin.Context) {
 	userID := c.Param("id")
 	currentUserID := c.GetString("user_id")
+
+	canView, err := h.userService.CanViewFollowing(c.Request.Context(), currentUserID, userID)
+	if err != nil {
+		response.InternalServerError(c, "failed to check privacy settings")
+		return
+	}
+	if !canView {
+		response.Forbidden(c, "该用户的关注列表不对外公开")
+		return
+	}
+
 	page := c.DefaultQuery("page", "1")
 	pageSize := c.DefaultQuery("page_size", "20")
 
@@ -654,6 +665,17 @@ func (h *UserHandler) GetFollowingList(c *gin.Context) {
 func (h *UserHandler) GetFollowersList(c *gin.Context) {
 	userID := c.Param("id")
 	currentUserID := c.GetString("user_id")
+
+	canView, err := h.userService.CanViewFollowers(c.Request.Context(), currentUserID, userID)
+	if err != nil {
+		response.InternalServerError(c, "failed to check privacy settings")
+		return
+	}
+	if !canView {
+		response.Forbidden(c, "该用户的粉丝列表不对外公开")
+		return
+	}
+
 	page := c.DefaultQuery("page", "1")
 	pageSize := c.DefaultQuery("page_size", "20")
 
@@ -810,3 +832,151 @@ func (h *UserHandler) Search(c *gin.Context) {
 
 	response.Paginated(c, userResponses, total, page, pageSize)
 }
+
+// GetPrivacySettings 获取隐私设置
+func (h *UserHandler) GetPrivacySettings(c *gin.Context) {
+	userID := c.GetString("user_id")
+	if userID == "" {
+		response.Unauthorized(c, "")
+		return
+	}
+
+	settings, err := h.userService.GetPrivacySettings(c.Request.Context(), userID)
+	if err != nil {
+		response.InternalServerError(c, "failed to get privacy settings")
+		return
+	}
+
+	response.Success(c, &dto.PrivacySettingsResponse{
+		FollowersVisibility: string(settings.FollowersVisibility),
+		FollowingVisibility: string(settings.FollowingVisibility),
+		PostsVisibility:     string(settings.PostsVisibility),
+		FavoritesVisibility: string(settings.FavoritesVisibility),
+	})
+}
+
+// UpdatePrivacySettings 更新隐私设置
+func (h *UserHandler) UpdatePrivacySettings(c *gin.Context) {
+	userID := c.GetString("user_id")
+	if userID == "" {
+		response.Unauthorized(c, "")
+		return
+	}
+
+	var req dto.PrivacySettingsRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		response.BadRequest(c, err.Error())
+		return
+	}
+
+	settings := &model.PrivacySettings{}
+	if req.FollowersVisibility != nil {
+		settings.FollowersVisibility = model.VisibilityLevel(*req.FollowersVisibility)
+	} else {
+		settings.FollowersVisibility = model.VisibilityEveryone
+	}
+	if req.FollowingVisibility != nil {
+		settings.FollowingVisibility = model.VisibilityLevel(*req.FollowingVisibility)
+	} else {
+		settings.FollowingVisibility = model.VisibilityEveryone
+	}
+	if req.PostsVisibility != nil {
+		settings.PostsVisibility = model.VisibilityLevel(*req.PostsVisibility)
+	} else {
+		settings.PostsVisibility = model.VisibilityEveryone
+	}
+	if req.FavoritesVisibility != nil {
+		settings.FavoritesVisibility = model.VisibilityLevel(*req.FavoritesVisibility)
+	} else {
+		settings.FavoritesVisibility = model.VisibilityEveryone
+	}
+
+	if err := h.userService.UpdatePrivacySettings(c.Request.Context(), userID, settings); err != nil {
+		response.InternalServerError(c, "failed to update privacy settings")
+		return
+	}
+
+	response.Success(c, &dto.PrivacySettingsResponse{
+		FollowersVisibility: string(settings.FollowersVisibility),
+		FollowingVisibility: string(settings.FollowingVisibility),
+		PostsVisibility:     string(settings.PostsVisibility),
+		FavoritesVisibility: string(settings.FavoritesVisibility),
+	})
+}
+
+// RequestAccountDeletion 申请注销账号
+func (h *UserHandler) RequestAccountDeletion(c *gin.Context) {
+	userID := c.GetString("user_id")
+	if userID == "" {
+		response.Unauthorized(c, "")
+		return
+	}
+
+	var req dto.RequestDeletionRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		response.BadRequest(c, err.Error())
+		return
+	}
+
+	if err := h.userService.RequestAccountDeletion(c.Request.Context(), userID, req.Password); err != nil {
+		response.HandleError(c, err, "failed to request account deletion")
+		return
+	}
+
+	isPending, requestedAt, daysLeft, err := h.userService.GetDeletionStatus(c.Request.Context(), userID)
+	if err != nil {
+		response.InternalServerError(c, "failed to get deletion status")
+		return
+	}
+
+	resp := &dto.DeletionStatusResponse{
+		IsPendingDeletion: isPending,
+		CoolDownDays:      daysLeft,
+	}
+	if requestedAt != nil {
+		resp.DeletionRequestedAt = dto.FormatTime(*requestedAt)
+	}
+
+	response.Success(c, resp)
+}
+
+// CancelAccountDeletion 取消注销
+func (h *UserHandler) CancelAccountDeletion(c *gin.Context) {
+	userID := c.GetString("user_id")
+	if userID == "" {
+		response.Unauthorized(c, "")
+		return
+	}
+
+	if err := h.userService.CancelAccountDeletion(c.Request.Context(), userID); err != nil {
+		response.InternalServerError(c, "failed to cancel account deletion")
+		return
+	}
+
+	response.Success(c, gin.H{"success": true})
+}
+
+// GetDeletionStatus 获取注销状态
+func (h *UserHandler) GetDeletionStatus(c *gin.Context) {
+	userID := c.GetString("user_id")
+	if userID == "" {
+		response.Unauthorized(c, "")
+		return
+	}
+
+	isPending, requestedAt, daysLeft, err := h.userService.GetDeletionStatus(c.Request.Context(), userID)
+	if err != nil {
+		response.InternalServerError(c, "failed to get deletion status")
+		return
+	}
+
+	resp := &dto.DeletionStatusResponse{
+		IsPendingDeletion: isPending,
+		CoolDownDays:      daysLeft,
+	}
+	if requestedAt != nil {
+		resp.DeletionRequestedAt = dto.FormatTime(*requestedAt)
+	}
+
+	response.Success(c, resp)
+}

internal/model/user.go

@@ -11,11 +11,29 @@ import (
 type UserStatus string
 
 const (
-	UserStatusActive   UserStatus = "active"
+	UserStatusActive          UserStatus = "active"
-	UserStatusBanned   UserStatus = "banned"
+	UserStatusBanned          UserStatus = "banned"
-	UserStatusInactive UserStatus = "inactive"
+	UserStatusInactive        UserStatus = "inactive"
+	UserStatusPendingDeletion UserStatus = "pending_deletion"
 )
 
+// VisibilityLevel 可见性级别
+type VisibilityLevel string
+
+const (
+	VisibilityEveryone  VisibilityLevel = "everyone"
+	VisibilityFollowing VisibilityLevel = "following"
+	VisibilitySelf      VisibilityLevel = "self"
+)
+
+// PrivacySettings 隐私设置
+type PrivacySettings struct {
+	FollowersVisibility VisibilityLevel `json:"followers_visibility" gorm:"type:varchar(20);default:everyone"`
+	FollowingVisibility VisibilityLevel `json:"following_visibility" gorm:"type:varchar(20);default:everyone"`
+	PostsVisibility     VisibilityLevel `json:"posts_visibility" gorm:"type:varchar(20);default:everyone"`
+	FavoritesVisibility VisibilityLevel `json:"favorites_visibility" gorm:"type:varchar(20);default:everyone"`
+}
+
 // UserIdentity 用户身份类型
 type UserIdentity string
 
@@ -73,6 +91,12 @@ type User struct {
 	LastLoginAt *time.Time `json:"last_login_at" gorm:"type:timestamp"`
 	LastLoginIP string     `json:"last_login_ip" gorm:"type:varchar(45)"`
 
+	// 账号注销
+	DeletionRequestedAt *time.Time `json:"deletion_requested_at" gorm:"type:timestamp"`
+
+	// 隐私设置
+	PrivacySettings PrivacySettings `json:"privacy_settings" gorm:"embedded;embeddedPrefix:privacy_"`
+
 	// 时间戳
 	CreatedAt time.Time      `json:"created_at" gorm:"autoCreateTime"`
 	UpdatedAt time.Time      `json:"updated_at" gorm:"autoUpdateTime"`

internal/repository/user_repo.go

@@ -3,6 +3,7 @@ package repository
 import (
 	"carrot_bbs/internal/model"
 	"strings"
+	"time"
 
 	"gorm.io/gorm"
 	"gorm.io/gorm/clause"
@@ -43,6 +44,16 @@ type UserRepository interface {
 	AdminList(page, pageSize int, keyword, status string) ([]*model.User, int64, error)
 	GetCommentsCount(userID string) (int64, error)
 	UpdateStatus(userID string, status model.UserStatus) error
+
+	// 隐私设置
+	UpdatePrivacySettings(userID string, settings *model.PrivacySettings) error
+	GetPrivacySettings(userID string) (*model.PrivacySettings, error)
+
+	// 账号注销
+	RequestDeletion(userID string) error
+	CancelDeletion(userID string) error
+	GetPendingDeletionUsers(beforeTime time.Time) ([]*model.User, error)
+	HardDeleteUser(userID string) error
 }
 
 // userRepository 用户仓储实现
@@ -544,3 +555,54 @@ func (r *userRepository) GetCommentsCount(userID string) (int64, error) {
 func (r *userRepository) UpdateStatus(userID string, status model.UserStatus) error {
 	return r.db.Model(&model.User{}).Where("id = ?", userID).Update("status", status).Error
 }
+
+// UpdatePrivacySettings 更新隐私设置
+func (r *userRepository) UpdatePrivacySettings(userID string, settings *model.PrivacySettings) error {
+	return r.db.Model(&model.User{}).Where("id = ?", userID).Updates(map[string]interface{}{
+		"privacy_followers_visibility": settings.FollowersVisibility,
+		"privacy_following_visibility": settings.FollowingVisibility,
+		"privacy_posts_visibility":     settings.PostsVisibility,
+		"privacy_favorites_visibility": settings.FavoritesVisibility,
+	}).Error
+}
+
+// GetPrivacySettings 获取隐私设置
+func (r *userRepository) GetPrivacySettings(userID string) (*model.PrivacySettings, error) {
+	var user model.User
+	err := r.db.Select("privacy_followers_visibility, privacy_following_visibility, privacy_posts_visibility, privacy_favorites_visibility").
+		First(&user, "id = ?", userID).Error
+	if err != nil {
+		return nil, err
+	}
+	return &user.PrivacySettings, nil
+}
+
+// RequestDeletion 申请注销账号
+func (r *userRepository) RequestDeletion(userID string) error {
+	now := time.Now()
+	return r.db.Model(&model.User{}).Where("id = ?", userID).Updates(map[string]interface{}{
+		"deletion_requested_at": &now,
+		"status":                model.UserStatusPendingDeletion,
+	}).Error
+}
+
+// CancelDeletion 取消注销
+func (r *userRepository) CancelDeletion(userID string) error {
+	return r.db.Model(&model.User{}).Where("id = ?", userID).Updates(map[string]interface{}{
+		"deletion_requested_at": nil,
+		"status":                model.UserStatusActive,
+	}).Error
+}
+
+// GetPendingDeletionUsers 获取待删除的用户列表（注销申请时间早于指定时间）
+func (r *userRepository) GetPendingDeletionUsers(beforeTime time.Time) ([]*model.User, error) {
+	var users []*model.User
+	err := r.db.Where("deletion_requested_at IS NOT NULL AND deletion_requested_at < ?", beforeTime).
+		Find(&users).Error
+	return users, err
+}
+
+// HardDeleteUser 硬删除用户（永久删除）
+func (r *userRepository) HardDeleteUser(userID string) error {
+	return r.db.Unscoped().Delete(&model.User{}, "id = ?", userID).Error
+}

internal/router/router.go

@@ -187,6 +187,15 @@ func (r *Router) setupRoutes() {
 			users.POST("/change-password/send-code", authMiddleware, r.userHandler.SendChangePasswordCode)
 			users.POST("/change-password", authMiddleware, r.userHandler.ChangePassword)
 
+			// 隐私设置
+			users.GET("/me/privacy", authMiddleware, r.userHandler.GetPrivacySettings)
+			users.PUT("/me/privacy", authMiddleware, r.userHandler.UpdatePrivacySettings)
+
+			// 账号注销
+			users.POST("/me/deactivate", authMiddleware, r.userHandler.RequestAccountDeletion)
+			users.DELETE("/me/deactivate", authMiddleware, r.userHandler.CancelAccountDeletion)
+			users.GET("/me/deletion-status", authMiddleware, r.userHandler.GetDeletionStatus)
+
 			// 当前用户角色
 			if r.roleHandler != nil {
 				users.GET("/me/roles", authMiddleware, r.roleHandler.GetMyRoles)

internal/service/account_cleanup_service.go

@@ -0,0 +1,109 @@
+package service
+
+import (
+	"context"
+	"log"
+	"time"
+
+	"carrot_bbs/internal/model"
+	"carrot_bbs/internal/repository"
+
+	"gorm.io/gorm"
+)
+
+const AccountDeletionCoolDownDays = 90
+
+type AccountCleanupService interface {
+	CleanupExpiredAccounts(ctx context.Context) (int64, error)
+}
+
+type accountCleanupServiceImpl struct {
+	db         *gorm.DB
+	userRepo   repository.UserRepository
+	logService *LogService
+}
+
+func NewAccountCleanupService(
+	db *gorm.DB,
+	userRepo repository.UserRepository,
+	logService *LogService,
+) AccountCleanupService {
+	return &accountCleanupServiceImpl{
+		db:         db,
+		userRepo:   userRepo,
+		logService: logService,
+	}
+}
+
+func (s *accountCleanupServiceImpl) CleanupExpiredAccounts(ctx context.Context) (int64, error) {
+	cutoffTime := time.Now().AddDate(0, 0, -AccountDeletionCoolDownDays)
+
+	users, err := s.userRepo.GetPendingDeletionUsers(cutoffTime)
+	if err != nil {
+		return 0, err
+	}
+
+	if len(users) == 0 {
+		return 0, nil
+	}
+
+	var deletedCount int64
+	for _, user := range users {
+		if err := s.anonymizeAndDeleteUser(ctx, user); err != nil {
+			log.Printf("[AccountCleanup] failed to cleanup user %s: %v", user.ID, err)
+			continue
+		}
+		deletedCount++
+	}
+
+	log.Printf("[AccountCleanup] cleaned up %d expired accounts", deletedCount)
+	return deletedCount, nil
+}
+
+func (s *accountCleanupServiceImpl) anonymizeAndDeleteUser(ctx context.Context, user *model.User) error {
+	deletedUserID := "deleted_user"
+
+	return s.db.Transaction(func(tx *gorm.DB) error {
+		if err := tx.Model(&model.Post{}).Where("user_id = ?", user.ID).Update("user_id", deletedUserID).Error; err != nil {
+			return err
+		}
+
+		if err := tx.Model(&model.Comment{}).Where("user_id = ?", user.ID).Update("user_id", deletedUserID).Error; err != nil {
+			return err
+		}
+
+		if err := tx.Where("follower_id = ? OR following_id = ?", user.ID, user.ID).Delete(&model.Follow{}).Error; err != nil {
+			return err
+		}
+
+		if err := tx.Where("user_id = ?", user.ID).Delete(&model.Favorite{}).Error; err != nil {
+			return err
+		}
+
+		if err := tx.Where("user_id = ?", user.ID).Delete(&model.PostLike{}).Error; err != nil {
+			return err
+		}
+
+		if err := tx.Where("user_id = ?", user.ID).Delete(&model.CommentLike{}).Error; err != nil {
+			return err
+		}
+
+		if err := tx.Unscoped().Delete(&model.User{}, "id = ?", user.ID).Error; err != nil {
+			return err
+		}
+
+		if s.logService != nil {
+			s.logService.OperationLog.RecordOperation(&model.OperationLog{
+				UserID:     user.ID,
+				UserName:   user.Username,
+				Operation:  "account_deleted",
+				Module:     "user",
+				TargetType: "user",
+				TargetID:   user.ID,
+				Status:     "success",
+			})
+		}
+
+		return nil
+	})
+}

internal/service/user_service.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"strings"
+	"time"
 
 	"carrot_bbs/internal/cache"
 	apperrors "carrot_bbs/internal/errors"
@@ -52,6 +53,20 @@ type UserService interface {
 	UnblockUser(ctx context.Context, blockerID, blockedID string) error
 	GetBlockedUsers(ctx context.Context, blockerID string, page, pageSize int) ([]*model.User, int64, error)
 	IsBlocked(ctx context.Context, blockerID, blockedID string) (bool, error)
+
+	// 隐私设置
+	GetPrivacySettings(ctx context.Context, userID string) (*model.PrivacySettings, error)
+	UpdatePrivacySettings(ctx context.Context, userID string, settings *model.PrivacySettings) error
+	CheckVisibility(ctx context.Context, viewerID, targetUserID string, visibility model.VisibilityLevel) (bool, error)
+	CanViewFollowers(ctx context.Context, viewerID, targetUserID string) (bool, error)
+	CanViewFollowing(ctx context.Context, viewerID, targetUserID string) (bool, error)
+	CanViewPosts(ctx context.Context, viewerID, targetUserID string) (bool, error)
+	CanViewFavorites(ctx context.Context, viewerID, targetUserID string) (bool, error)
+
+	// 账号注销
+	RequestAccountDeletion(ctx context.Context, userID, password string) error
+	CancelAccountDeletion(ctx context.Context, userID string) error
+	GetDeletionStatus(ctx context.Context, userID string) (isPending bool, requestedAt *time.Time, daysLeft int, err error)
 }
 
 // userServiceImpl 用户服务实现
@@ -320,11 +335,10 @@ func (s *userServiceImpl) Login(ctx context.Context, account, password string) (
 		return nil, ErrInvalidCredentials
 	}
 
-	if user.Status != model.UserStatusActive {
+	if user.Status != model.UserStatusActive && user.Status != model.UserStatusPendingDeletion {
 		loginResult = string(model.LoginResultFail)
 		failReason = string(model.FailReasonAccountBanned)
 
-		// 记录失败登录日志
 		if s.logService != nil {
 			s.logService.LoginLog.RecordLogin(&model.LoginLog{
 				UserID:     user.ID,
@@ -341,6 +355,13 @@ func (s *userServiceImpl) Login(ctx context.Context, account, password string) (
 		return nil, ErrUserBanned
 	}
 
+	// 如果用户已申请注销，登录即取消注销
+	if user.DeletionRequestedAt != nil {
+		_ = s.userRepo.CancelDeletion(user.ID)
+		user.DeletionRequestedAt = nil
+		user.Status = model.UserStatusActive
+	}
+
 	// 记录成功登录日志
 	if s.logService != nil {
 		s.logService.LoginLog.RecordLogin(&model.LoginLog{
@@ -700,6 +721,107 @@ func (s *userServiceImpl) Search(ctx context.Context, keyword string, page, page
 	return s.userRepo.Search(keyword, page, pageSize)
 }
 
+// GetPrivacySettings 获取隐私设置
+func (s *userServiceImpl) GetPrivacySettings(ctx context.Context, userID string) (*model.PrivacySettings, error) {
+	return s.userRepo.GetPrivacySettings(userID)
+}
+
+// UpdatePrivacySettings 更新隐私设置
+func (s *userServiceImpl) UpdatePrivacySettings(ctx context.Context, userID string, settings *model.PrivacySettings) error {
+	return s.userRepo.UpdatePrivacySettings(userID, settings)
+}
+
+// CheckVisibility 检查可见性权限
+func (s *userServiceImpl) CheckVisibility(ctx context.Context, viewerID, targetUserID string, visibility model.VisibilityLevel) (bool, error) {
+	switch visibility {
+	case model.VisibilityEveryone:
+		return true, nil
+	case model.VisibilityFollowing:
+		if viewerID == "" {
+			return false, nil
+		}
+		return s.userRepo.IsFollowing(viewerID, targetUserID)
+	case model.VisibilitySelf:
+		return viewerID == targetUserID, nil
+	default:
+		return false, nil
+	}
+}
+
+// CanViewFollowers 检查是否可以查看粉丝列表
+func (s *userServiceImpl) CanViewFollowers(ctx context.Context, viewerID, targetUserID string) (bool, error) {
+	settings, err := s.userRepo.GetPrivacySettings(targetUserID)
+	if err != nil {
+		return false, err
+	}
+	return s.CheckVisibility(ctx, viewerID, targetUserID, settings.FollowersVisibility)
+}
+
+// CanViewFollowing 检查是否可以查看关注列表
+func (s *userServiceImpl) CanViewFollowing(ctx context.Context, viewerID, targetUserID string) (bool, error) {
+	settings, err := s.userRepo.GetPrivacySettings(targetUserID)
+	if err != nil {
+		return false, err
+	}
+	return s.CheckVisibility(ctx, viewerID, targetUserID, settings.FollowingVisibility)
+}
+
+// CanViewPosts 检查是否可以查看帖子列表
+func (s *userServiceImpl) CanViewPosts(ctx context.Context, viewerID, targetUserID string) (bool, error) {
+	settings, err := s.userRepo.GetPrivacySettings(targetUserID)
+	if err != nil {
+		return false, err
+	}
+	return s.CheckVisibility(ctx, viewerID, targetUserID, settings.PostsVisibility)
+}
+
+// CanViewFavorites 检查是否可以查看收藏列表
+func (s *userServiceImpl) CanViewFavorites(ctx context.Context, viewerID, targetUserID string) (bool, error) {
+	settings, err := s.userRepo.GetPrivacySettings(targetUserID)
+	if err != nil {
+		return false, err
+	}
+	return s.CheckVisibility(ctx, viewerID, targetUserID, settings.FavoritesVisibility)
+}
+
+// RequestAccountDeletion 申请注销账号
+func (s *userServiceImpl) RequestAccountDeletion(ctx context.Context, userID, password string) error {
+	user, err := s.userRepo.GetByID(userID)
+	if err != nil {
+		return ErrUserNotFound
+	}
+
+	if !utils.CheckPasswordHash(password, user.PasswordHash) {
+		return ErrInvalidCredentials
+	}
+
+	return s.userRepo.RequestDeletion(userID)
+}
+
+// CancelAccountDeletion 取消注销
+func (s *userServiceImpl) CancelAccountDeletion(ctx context.Context, userID string) error {
+	return s.userRepo.CancelDeletion(userID)
+}
+
+// GetDeletionStatus 获取注销状态
+func (s *userServiceImpl) GetDeletionStatus(ctx context.Context, userID string) (isPending bool, requestedAt *time.Time, daysLeft int, err error) {
+	user, err := s.userRepo.GetByID(userID)
+	if err != nil {
+		return false, nil, 0, err
+	}
+
+	if user.DeletionRequestedAt == nil {
+		return false, nil, 0, nil
+	}
+
+	daysLeft = 90 - int(time.Since(*user.DeletionRequestedAt).Hours()/24)
+	if daysLeft < 0 {
+		daysLeft = 0
+	}
+
+	return true, user.DeletionRequestedAt, daysLeft, nil
+}
+
 // 错误定义 - 使用统一的 AppError
 var (
 	ErrInvalidUsername             = apperrors.ErrInvalidUsername