Auto create ProductInventory entities

modules/EasyAbp.EShop.Products/src/EasyAbp.EShop.Products.Domain/EasyAbp/EShop/Products/Products/DefaultProductInventoryProvider.cs

@@ -5,6 +5,8 @@ using System.Threading.Tasks;
 using EasyAbp.EShop.Products.ProductInventories;
 using Volo.Abp.DependencyInjection;
 using Volo.Abp.EventBus.Distributed;
+using Volo.Abp.Guids;
+using Volo.Abp.MultiTenancy;
 using Volo.Abp.Uow;
 
 namespace EasyAbp.EShop.Products.Products
@@ -12,15 +14,21 @@ namespace EasyAbp.EShop.Products.Products
     public class DefaultProductInventoryProvider : IProductInventoryProvider, ITransientDependency
     {
         // Todo: should use IProductInventoryStore.
+        private readonly IGuidGenerator _guidGenerator;
+        private readonly ICurrentTenant _currentTenant;
         private readonly IUnitOfWorkManager _unitOfWorkManager;
         private readonly IDistributedEventBus _distributedEventBus;
         private readonly IProductInventoryRepository _productInventoryRepository;
 
         public DefaultProductInventoryProvider(
+            IGuidGenerator guidGenerator,
+            ICurrentTenant currentTenant,
             IUnitOfWorkManager unitOfWorkManager,
             IDistributedEventBus distributedEventBus,
             IProductInventoryRepository productInventoryRepository)
         {
+            _guidGenerator = guidGenerator;
+            _currentTenant = currentTenant;
             _unitOfWorkManager = unitOfWorkManager;
             _distributedEventBus = distributedEventBus;
             _productInventoryRepository = productInventoryRepository;
@@ -49,7 +57,7 @@ namespace EasyAbp.EShop.Products.Products
         [UnitOfWork(true)]
         public virtual async Task<bool> TryIncreaseInventoryAsync(Product product, ProductSku productSku, int quantity, bool decreaseSold)
         {
-            var productInventory = await _productInventoryRepository.GetAsync(x => x.ProductSkuId == productSku.Id);
+            var productInventory = await GetOrCreateProductInventoryAsync(product.Id, productSku.Id);
             
             return await TryIncreaseInventoryAsync(product, productInventory, quantity, decreaseSold);
         }
@@ -57,11 +65,29 @@ namespace EasyAbp.EShop.Products.Products
         [UnitOfWork(true)]
         public virtual async Task<bool> TryReduceInventoryAsync(Product product, ProductSku productSku, int quantity, bool increaseSold)
         {
-            var productInventory = await _productInventoryRepository.GetAsync(x => x.ProductSkuId == productSku.Id);
+            var productInventory = await GetOrCreateProductInventoryAsync(product.Id, productSku.Id);
             
             return await TryReduceInventoryAsync(product, productInventory, quantity, increaseSold);
         }
         
+        [UnitOfWork]
+        protected virtual async Task<ProductInventory> GetOrCreateProductInventoryAsync(Guid productId, Guid productSkuId)
+        {
+            var productInventory =
+                await _productInventoryRepository.FindAsync(x =>
+                    x.ProductId == productId && x.ProductSkuId == productSkuId);
+            
+            if (productInventory is null)
+            {
+                productInventory = new ProductInventory(_guidGenerator.Create(), _currentTenant.Id, productId,
+                    productSkuId, 0, 0);
+
+                await _productInventoryRepository.InsertAsync(productInventory, true);
+            }
+
+            return productInventory;
+        }
+        
         [UnitOfWork(true)]
         public virtual async Task<bool> TryIncreaseInventoryAsync(Product product, ProductInventory productInventory, int quantity, bool decreaseSold)
         {