补齐论坛核心能力：讨论锁定、发帖本地草稿、标签精确筛选，以及私信与通知分流。

Co-authored-by: Cursor <cursoragent@cursor.com>

service/comment.go

@@ -194,6 +194,11 @@ func (s *CommentService) Create(in CommentCreateInput) (*model.Comment, error) {
 		return nil, errors.New("账号已被禁言")
 	}
 
+	// 讨论锁定：管理员亦不可强评（避免结贴后仍被顶楼）
+	if post.CommentsLocked {
+		return nil, ErrPostCommentsLocked
+	}
+
 	// 未公开帖仅作者/管理员可评论
 	if post.Status != model.ContentStatusPublished && post.Status != "" {
 		if user.Role != model.RoleAdmin && post.UserID != in.UserID {

service/common.go

@@ -25,6 +25,7 @@ var (
 	ErrPermissionDenied      = errors.New("无权操作")
 	ErrBoardNotFound         = errors.New("板块不存在")
 	ErrPostEditLocked        = errors.New("帖子已被管理员锁定，无法编辑")
+	ErrPostCommentsLocked    = errors.New("该帖子已锁定讨论，无法评论")
 	ErrPostEditExpired       = errors.New("已超过可编辑时限")
 	ErrRevisionNotFound      = errors.New("历史版本不存在")
 	ErrInvalidSetting        = errors.New("无效的设置值")

service/message.go

@@ -130,6 +130,59 @@ func (s *MessageService) UnreadCount(userID uint) (int64, error) {
 	return n, err
 }
 
+// UnreadCounts 未读总数，以及私信 / 系统通知分项
+func (s *MessageService) UnreadCounts(userID uint) (total, dm, notify int64, err error) {
+	err = model.DB.Model(&model.PrivateMessage{}).
+		Where("to_user_id = ? AND is_read = ?", userID, false).
+		Count(&total).Error
+	if err != nil {
+		return 0, 0, 0, err
+	}
+	err = model.DB.Model(&model.PrivateMessage{}).
+		Where("to_user_id = ? AND is_read = ? AND from_user_id = 0", userID, false).
+		Count(&notify).Error
+	if err != nil {
+		return 0, 0, 0, err
+	}
+	dm = total - notify
+	if dm < 0 {
+		dm = 0
+	}
+	return total, dm, notify, nil
+}
+
+// ListNotifications 系统通知列表（按时间倒序，非聊天气泡）
+func (s *MessageService) ListNotifications(userID uint, page, size int, kind string) ([]model.PrivateMessage, int64, error) {
+	if page < 1 {
+		page = 1
+	}
+	size = s.settings.NormalizePageSize(size)
+	db := model.DB.Model(&model.PrivateMessage{}).
+		Where("from_user_id = 0 AND to_user_id = ?", userID)
+	kind = strings.TrimSpace(kind)
+	if kind != "" && kind != "all" {
+		db = db.Where("kind = ?", kind)
+	}
+	var total int64
+	if err := db.Count(&total).Error; err != nil {
+		return nil, 0, err
+	}
+	var list []model.PrivateMessage
+	err := db.Order("id desc").Offset((page - 1) * size).Limit(size).Find(&list).Error
+	if err != nil {
+		return nil, 0, err
+	}
+	if list == nil {
+		list = []model.PrivateMessage{}
+	}
+	return list, total, nil
+}
+
+// MarkNotificationsRead 将系统通知全部标为已读
+func (s *MessageService) MarkNotificationsRead(userID uint) error {
+	return s.MarkConversationRead(userID, 0)
+}
+
 // MessageConversation 按对方聚合的会话摘要
 type MessageConversation struct {
 	PeerUserID  uint                 `json:"peer_user_id"` // 0 = 系统通知

service/post.go

@@ -34,6 +34,7 @@ type PostListQuery struct {
 	Page          int
 	Size          int
 	Keyword       string
+	Tag           string // 精确标签筛选（整枚匹配，不走 keyword LIKE）
 	Sort          string // latest | reply | hot
 	ViewerID      uint   // 当前查看者（用于 pending 仅作者可见）
 	ViewerIsAdmin bool
@@ -271,6 +272,12 @@ func (s *PostService) List(q PostListQuery) ([]model.Post, int64, error) {
 		kw := "%" + q.Keyword + "%"
 		db = db.Where("title LIKE ? OR content_plain LIKE ? OR tags LIKE ?", kw, kw, kw)
 	}
+	if tag := strings.TrimSpace(q.Tag); tag != "" {
+		// 整枚标签匹配：逗号/中文逗号分隔，忽略标签两侧空格，大小写不敏感
+		escaped := escapeLikePattern(strings.ToLower(tag))
+		normalized := "LOWER(',' || REPLACE(REPLACE(REPLACE(IFNULL(tags,''), '，', ','), ', ', ','), ' ,', ',') || ',')"
+		db = db.Where(normalized+" LIKE ? ESCAPE '\\'", "%,"+escaped+",%")
+	}
 	var total int64
 	db.Count(&total)
 	var posts []model.Post
@@ -310,6 +317,14 @@ func normalizePostSort(sort string) string {
 	}
 }
 
+// escapeLikePattern 转义 LIKE 通配符，配合 ESCAPE '\'
+func escapeLikePattern(s string) string {
+	s = strings.ReplaceAll(s, `\`, `\\`)
+	s = strings.ReplaceAll(s, `%`, `\%`)
+	s = strings.ReplaceAll(s, `_`, `\_`)
+	return s
+}
+
 func (s *PostService) FindByID(id uint) (*model.Post, error) {
 	var post model.Post
 	err := model.DB.Preload("User").Preload("Board").First(&post, id).Error
@@ -535,6 +550,18 @@ func (s *PostService) SetEditLocked(postID uint, locked bool) error {
 	return nil
 }
 
+// SetCommentsLocked 锁定/解锁讨论（禁止新评论）
+func (s *PostService) SetCommentsLocked(postID uint, locked bool) error {
+	res := model.DB.Model(&model.Post{}).Where("id = ?", postID).Update("comments_locked", locked)
+	if res.Error != nil {
+		return res.Error
+	}
+	if res.RowsAffected == 0 {
+		return ErrPostNotFound
+	}
+	return nil
+}
+
 func (s *PostService) ListRevisions(postID uint) ([]model.PostRevision, error) {
 	var revs []model.PostRevision
 	err := model.DB.Preload("Editor").Where("post_id = ?", postID).