fix(chat): 回复后再移出待处理

backend/internal/modules/chat/admin_list_test.go

@@ -99,6 +99,9 @@ func TestListAdminConversationsUsesPersonalStateAndBatchData(t *testing.T) {
 	if item.UnreadCount != 1 {
 		t.Fatalf("管理员未读数 = %d, want 1", item.UnreadCount)
 	}
+	if !item.NeedsReply {
+		t.Fatal("用户消息未回复时应保持待处理")
+	}
 	counts, err := repo.AdminConversationCounts(t.Context(), Principal{Type: "admin", ID: admin.ID}, adminChatFilterMine, adminChatStageAll, "")
 	if err != nil {
 		t.Fatalf("查询客服统计失败: %v", err)
@@ -106,4 +109,23 @@ func TestListAdminConversationsUsesPersonalStateAndBatchData(t *testing.T) {
 	if counts.Ownership[adminChatFilterMine] != 1 || counts.Stages[adminChatStageAll] != 1 {
 		t.Fatalf("聚合统计异常: ownership=%v stages=%v", counts.Ownership, counts.Stages)
 	}
+
+	adminMessage := model.ChatMessage{ConversationID: conversation.ID, SenderType: "admin", SenderID: admin.ID, SenderRole: "support", ContentType: "text", Content: "客服回复", CreatedAt: now.Add(2 * time.Second)}
+	if err := db.Create(&adminMessage).Error; err != nil {
+		t.Fatalf("创建客服回复失败: %v", err)
+	}
+	if err := db.Model(&conversation).Updates(map[string]interface{}{
+		"last_message_id":      adminMessage.ID,
+		"last_message_preview": adminMessage.Content,
+		"last_message_at":      adminMessage.CreatedAt,
+	}).Error; err != nil {
+		t.Fatalf("更新客服回复摘要失败: %v", err)
+	}
+	result, err = repo.ListConversationsWithFilter(t.Context(), Principal{Type: "admin", ID: admin.ID}, 1, 20, adminChatFilterMine, adminChatStagePending, "")
+	if err != nil {
+		t.Fatalf("查询已回复待处理会话失败: %v", err)
+	}
+	if result.Total != 0 {
+		t.Fatalf("客服回复后待处理数量 = %d, want 0", result.Total)
+	}
 }

backend/internal/modules/chat/dto.go

@@ -30,6 +30,7 @@ type ConversationDTO struct {
 	LastSenderID        uint64           `json:"last_sender_id,omitempty"`
 	LastSenderRole      string           `json:"last_sender_role,omitempty"`
 	UnreadCount         int64            `json:"unread_count"`
+	NeedsReply          bool             `json:"needs_reply"`
 	CreatedAt           time.Time        `json:"created_at"`
 	UpdatedAt           time.Time        `json:"updated_at"`
 }

backend/internal/modules/chat/participant.go

@@ -33,6 +33,7 @@ type conversationRow struct {
 	LastSenderID        uint64
 	LastSenderRole      string
 	UnreadCount         int64
+	NeedsReply          int64
 	CreatedAt           time.Time
 	UpdatedAt           time.Time
 }
@@ -333,6 +334,7 @@ func (row conversationRow) toDTO(participants []ParticipantDTO) ConversationDTO
 		LastSenderID:        row.LastSenderID,
 		LastSenderRole:      row.LastSenderRole,
 		UnreadCount:         row.UnreadCount,
+		NeedsReply:          row.NeedsReply > 0,
 		CreatedAt:           row.CreatedAt,
 		UpdatedAt:           row.UpdatedAt,
 	}

backend/internal/modules/chat/support.go

@@ -239,6 +239,7 @@ func (r *Repository) listAdminConversations(ctx context.Context, principal Princ
 			COALESCE(explicit_lo.handoff_status, listing_lo.handoff_status) AS latest_handoff_status,
 			COALESCE(explicit_lo.refund_status, listing_lo.refund_status) AS latest_refund_status,
 			lm.sender_type AS last_sender_type, lm.sender_id AS last_sender_id, lm.sender_role AS last_sender_role,
+			CASE WHEN ` + adminNeedsReplyExpression() + ` THEN 1 ELSE 0 END AS needs_reply,
 			(
 				SELECT COUNT(1)
 				FROM chat_messages AS cm
@@ -414,13 +415,7 @@ func adminChatStageCondition(stage string, principal Principal) (string, []inter
 	latestRefundStatus := "COALESCE(explicit_lo.refund_status, listing_lo.refund_status)"
 	switch stage {
 	case adminChatStagePending:
-		return `EXISTS (
-				SELECT 1
-				FROM chat_messages AS cm_pending
-				WHERE cm_pending.conversation_id = c.id
-					  AND (cm_pending.admin_attention_type <> '' OR cm_pending.sender_type = 'user')
-					  AND cm_pending.id > COALESCE(cas.last_read_message_id, 0)
-			)`, nil
+		return adminNeedsReplyExpression(), nil
 	case adminChatStageUnjoined:
 		return latestID + " IS NULL", nil
 	case adminChatStageHandoff:
@@ -438,6 +433,20 @@ func adminChatStageCondition(stage string, principal Principal) (string, []inter
 	}
 }
 
+func adminNeedsReplyExpression() string {
+	return `COALESCE((
+		SELECT MAX(cm_attention.id)
+		FROM chat_messages AS cm_attention
+		WHERE cm_attention.conversation_id = c.id
+		  AND (cm_attention.admin_attention_type <> '' OR cm_attention.sender_type = 'user')
+	), 0) > COALESCE((
+		SELECT MAX(cm_admin.id)
+		FROM chat_messages AS cm_admin
+		WHERE cm_admin.conversation_id = c.id
+		  AND cm_admin.sender_type = 'admin'
+	), 0)`
+}
+
 // ArchiveListingConversation 将商品关联的发布群标记为已归档（解散），并写入系统提示。
 // 用于客服封存订单时同事务解散群聊；发布群不存在时静默跳过，不阻断封存流程。
 // 归档后 SendMessage 的 status 校验会阻断所有成员继续发言。