protected IEnumerable GroupRelationshipsByDescription()

in src/Foundation/CommerceServer/code/Managers/CatalogManager.cs [630:691]
53 lines of code
14 McCabe index (conditional complexity)

        protected IEnumerable<CategoryViewModel> GroupRelationshipsByDescription([NotNull] CommerceStorefront storefront, [NotNull] IVisitorContext visitorContext, RelationshipField field, IEnumerable<string> relationshipNames, IEnumerable<CatalogRelationshipInformation> productRelationshipInfoList, Rendering rendering)
        {
            var relationshipGroups = new Dictionary<string, CategoryViewModel>(StringComparer.OrdinalIgnoreCase);

            if (field != null && productRelationshipInfoList != null)
            {
                foreach (var relationshipInfo in productRelationshipInfoList)
                {
                    if (!relationshipNames.Any() || relationshipNames.Contains(relationshipInfo.RelationshipName, StringComparer.OrdinalIgnoreCase))
                    {
                        Item lookupItem = null;
                        bool usingRelationshipName = string.IsNullOrWhiteSpace(relationshipInfo.RelationshipDescription);
                        var relationshipDescription = string.IsNullOrWhiteSpace(relationshipInfo.RelationshipDescription) ? StorefrontManager.GetRelationshipName(relationshipInfo.RelationshipName, out lookupItem) : relationshipInfo.RelationshipDescription;
                        CategoryViewModel categoryModel;
                        if (!relationshipGroups.TryGetValue(relationshipDescription, out categoryModel))
                        {
                            categoryModel = new CategoryViewModel
                            {
                                ChildProducts = new List<ProductViewModel>(),
                                RelationshipName = relationshipInfo.RelationshipName,
                                RelationshipDescription = relationshipDescription,
                                LookupRelationshipItem = (usingRelationshipName) ? lookupItem : null
                            };

                            relationshipGroups[relationshipDescription] = categoryModel;
                        }

                        var targetItemId = ID.Parse(relationshipInfo.ToItemExternalId);
                        var targetItem = field.InnerField.Database.GetItem(targetItemId);
                        var productModel = new ProductViewModel(targetItem);
                        productModel.Initialize(rendering);

                        this.GetProductRating(targetItem);

                        categoryModel.ChildProducts.Add(productModel);
                    }
                }
            }

            if (relationshipGroups.Count > 0)
            {
                List<ProductViewModel> productViewModelList = new List<ProductViewModel>();

                foreach (string key in relationshipGroups.Keys)
                {
                    CategoryViewModel viewModel = relationshipGroups[key];
                    var childProducts = viewModel.ChildProducts;
                    if (childProducts != null && childProducts.Count > 0)
                    {
                        productViewModelList.AddRange(childProducts);
                    }
                }

                if (productViewModelList.Count > 0)
                {
                    this.GetProductBulkPrices(visitorContext, productViewModelList);
                    this.InventoryManager.GetProductsStockStatusForList(storefront, productViewModelList);
                }
            }

            return relationshipGroups.Values;
        }