实现AssignEmptyPensToBatch

internal/domain/pig/pig_batch.go

@@ -46,21 +46,25 @@ type PigBatchService interface {
 	ListPigBatches(isActive *bool) ([]*models.PigBatch, error)
 	// UpdatePigBatchPens 更新猪批次关联的猪栏。
 	UpdatePigBatchPens(batchID uint, desiredPenIDs []uint) error
+	// AssignEmptyPensToBatch 为猪群分配空栏
+	AssignEmptyPensToBatch(batchID uint, penIDs []uint, operatorID uint) error
+	// MovePigsIntoPen 将猪只从“虚拟库存”移入指定猪栏
+	MovePigsIntoPen(batchID uint, toPenID uint, quantity int, operatorID uint, remarks string) error
+	// ReclassifyPenToNewBatch 连猪带栏，整体划拨到另一个猪群
+	ReclassifyPenToNewBatch(fromBatchID uint, toBatchID uint, penID uint, operatorID uint, remarks string) error
 
 	// GetCurrentPigQuantity 获取指定猪批次的当前猪只数量。
 	GetCurrentPigQuantity(batchID uint) (int, error)
 
 	UpdatePigBatchQuantity(operatorID uint, batchID uint, changeType models.LogChangeType, changeAmount int, changeReason string, happenedAt time.Time) error
 
-	// 交易子服务
+	// ---交易子服务---
-
 	// SellPigs 处理卖猪的业务逻辑。
 	SellPigs(batchID uint, penID uint, quantity int, unitPrice float64, tatalPrice float64, traderName string, tradeDate time.Time, remarks string, operatorID uint) error
 	// BuyPigs 处理买猪的业务逻辑。
 	BuyPigs(batchID uint, penID uint, quantity int, unitPrice float64, tatalPrice float64, traderName string, tradeDate time.Time, remarks string, operatorID uint) error
 
-	// 调栏子服务
+	// ---调栏子服务 ---
-
 	TransferPigsAcrossBatches(sourceBatchID uint, destBatchID uint, fromPenID uint, toPenID uint, quantity uint, operatorID uint, remarks string) error
 	TransferPigsWithinBatch(batchID uint, fromPenID uint, toPenID uint, quantity uint, operatorID uint, remarks string) error
 }

internal/domain/pig/pig_batch_service_pen_transfer.go

@@ -158,3 +158,60 @@ func (s *pigBatchService) TransferPigsAcrossBatches(sourceBatchID uint, destBatc
 		return nil
 	})
 }
+
+// AssignEmptyPensToBatch 为猪群分配空栏
+func (s *pigBatchService) AssignEmptyPensToBatch(batchID uint, penIDs []uint, operatorID uint) error {
+	return s.uow.ExecuteInTransaction(func(tx *gorm.DB) error {
+		// 1. 验证猪批次是否存在且活跃
+		pigBatch, err := s.pigBatchRepo.GetPigBatchByIDTx(tx, batchID)
+		if err != nil {
+			if errors.Is(err, gorm.ErrRecordNotFound) {
+				return ErrPigBatchNotFound
+			}
+			return fmt.Errorf("获取猪批次信息失败: %w", err)
+		}
+		if !pigBatch.IsActive() {
+			return ErrPigBatchNotActive
+		}
+
+		// 2. 遍历并校验每一个待分配的猪栏
+		for _, penID := range penIDs {
+			pen, err := s.transferSvc.GetPenByID(tx, penID)
+			if err != nil {
+				if errors.Is(err, gorm.ErrRecordNotFound) {
+					return fmt.Errorf("猪栏 %d 不存在: %w", penID, ErrPenNotFound)
+				}
+				return fmt.Errorf("获取猪栏 %d 信息失败: %w", penID, err)
+			}
+
+			// 核心业务规则：校验猪栏是否完全空闲
+			if pen.Status != models.PenStatusEmpty {
+				return fmt.Errorf("猪栏 %s 状态不为空 (%s)，无法分配", pen.PenNumber, pen.Status)
+			}
+			if pen.PigBatchID != nil {
+				return fmt.Errorf("猪栏 %s 已被其他批次 %d 占用，无法分配", pen.PenNumber, *pen.PigBatchID)
+			}
+
+			// 3. 更新猪栏的归属
+			updates := map[string]interface{}{
+				"pig_batch_id": &batchID,
+				"status":       models.PenStatusOccupied,
+			}
+			if err := s.transferSvc.UpdatePenFields(tx, penID, updates); err != nil {
+				return fmt.Errorf("分配猪栏 %d 失败: %w", penID, err)
+			}
+		}
+
+		return nil
+	})
+}
+
+// MovePigsIntoPen 将猪只从“虚拟库存”移入指定猪栏
+func (s *pigBatchService) MovePigsIntoPen(batchID uint, toPenID uint, quantity int, operatorID uint, remarks string) error {
+	panic("implement me")
+}
+
+// ReclassifyPenToNewBatch 连猪带栏，整体划拨到另一个猪群
+func (s *pigBatchService) ReclassifyPenToNewBatch(fromBatchID uint, toBatchID uint, penID uint, operatorID uint, remarks string) error {
+	panic("implement me")
+}