f

app/main/api/internal/service/agentService.go

@@ -876,6 +876,102 @@ func (s *AgentService) ProcessUpgrade(ctx context.Context, agentId string, toLev
 	})
 }
 
+// UpgradeTypeAdminDowngrade 管理端降级
+const UpgradeTypeAdminDowngrade int64 = 4
+
+// ProcessDowngrade 管理端代理降级（仅降低等级，不退款、不收回历史返佣）
+func (s *AgentService) ProcessDowngrade(ctx context.Context, agentId string, toLevel int64, remark string) error {
+	return s.AgentWalletModel.Trans(ctx, func(transCtx context.Context, session sqlx.Session) error {
+		agent, err := s.AgentModel.FindOne(transCtx, agentId)
+		if err != nil {
+			if errors.Is(err, model.ErrNotFound) {
+				return errors.New("代理不存在")
+			}
+			return errors.Wrapf(err, "查询代理失败")
+		}
+
+		fromLevel := agent.Level
+		if fromLevel == 3 {
+			return errors.New("钻石代理不允许降级")
+		}
+		if fromLevel == 1 {
+			return errors.New("普通代理无法降级")
+		}
+		if fromLevel != 2 || toLevel != 1 {
+			return errors.New("仅支持将黄金代理降级为普通代理")
+		}
+
+		if err := s.validateDowngradeDirectChildren(transCtx, agentId, toLevel); err != nil {
+			return err
+		}
+
+		if remark == "" {
+			remark = "管理端降级"
+		}
+
+		upgradeRecord := &model.AgentUpgrade{
+			Id:          uuid.NewString(),
+			AgentId:     agent.Id,
+			FromLevel:   fromLevel,
+			ToLevel:     toLevel,
+			UpgradeType: UpgradeTypeAdminDowngrade,
+			UpgradeFee:  0,
+			Status:      2, // 已完成
+			Remark:      lzUtils.StringToNullString(remark),
+		}
+		if _, err := s.AgentUpgradeModel.Insert(transCtx, session, upgradeRecord); err != nil {
+			return errors.Wrapf(err, "创建降级记录失败")
+		}
+
+		agent.Level = toLevel
+
+		teamLeaderId, err := s.findTeamLeaderId(transCtx, agentId)
+		if err != nil && !errors.Is(err, model.ErrNotFound) {
+			return errors.Wrapf(err, "查找团队首领失败")
+		}
+		if teamLeaderId != "" {
+			agent.TeamLeaderId = sql.NullString{String: teamLeaderId, Valid: true}
+		} else {
+			agent.TeamLeaderId = sql.NullString{Valid: false}
+		}
+
+		if err := s.AgentModel.UpdateWithVersion(transCtx, session, agent); err != nil {
+			return errors.Wrapf(err, "更新代理等级失败")
+		}
+
+		return nil
+	})
+}
+
+// validateDowngradeDirectChildren 校验直接下级是否允许上级降到 toLevel
+func (s *AgentService) validateDowngradeDirectChildren(ctx context.Context, agentId string, toLevel int64) error {
+	builder := s.AgentRelationModel.SelectBuilder().
+		Where("parent_id = ? AND relation_type = ? AND del_state = ?", agentId, 1, globalkey.DelStateNo)
+	relations, err := s.AgentRelationModel.FindAll(ctx, builder, "")
+	if err != nil {
+		return errors.Wrapf(err, "查询直接下级失败")
+	}
+
+	for _, relation := range relations {
+		child, err := s.AgentModel.FindOne(ctx, relation.ChildId)
+		if err != nil {
+			if errors.Is(err, model.ErrNotFound) {
+				continue
+			}
+			return errors.Wrapf(err, "查询下级代理失败")
+		}
+
+		if child.Level > toLevel {
+			return fmt.Errorf("存在等级高于目标等级的直接下级（下级ID: %s），无法降级", child.Id)
+		}
+		if child.Level == toLevel && toLevel >= 2 {
+			return fmt.Errorf("存在与目标等级相同的黄金/钻石直接下级（下级ID: %s），无法降级", child.Id)
+		}
+	}
+
+	return nil
+}
+
 // needDetachFromParent 检查是否需要脱离直接上级关系
 func (s *AgentService) needDetachFromParent(ctx context.Context, agent *model.Agent, newLevel int64) (bool, error) {
 	parent, err := s.findDirectParent(ctx, agent.Id)