fix on shelf

repositories/productRepository.go

@@ -46,6 +46,9 @@ type ProductRepository interface {
 	PublishProduct(tenantID, productID int, price, taxPercent float64) (int, error)
 	UnpublishProduct(tenantID, productID int) (int, error)
 	FindTenantProductByCatalogueRef(tenantid int, brand string, catalogueid int64) (*models.Products, error)
+	FindTenantProductByImageID(tenantid int, imageid string) (*models.Products, error)
+	SetCatalogueLink(productid int, imageid string, catalogueid int) error
+	ListCatalogueLinkedProducts(tenantid int) ([]models.Products, error)
 	CreateProductReturningID(product models.Products) (int, error)
 	GetImportedCatalogueRefs(tenantid int, brand string) ([]models.ImportedCatalogueRef, error)
 	GetTenantCategories(tenantid int) ([]models.TenantCategory, error)
@@ -1216,6 +1219,60 @@ func (r *productRepository) CreateProductReturningID(product models.Products) (i
 	return product.Productid, nil
 }
 
+// FindTenantProductByImageID looks up a tenant's snapshot by the catalogue's
+// own stable key.
+//
+// Preferred over FindTenantProductByCatalogueRef wherever an image_id is
+// available, because that one keys on a number the catalogue renumbers. After a
+// re-scrape the id no longer names the product it was stored for, so the lookup
+// misses, the import believes it is seeing the product for the first time, and
+// the shop gets a second copy of something it already stocks.
+//
+// No brand in the key: image_id already carries it (`cheetos_chips_2d6bf74f`,
+// `pepsico_kurkure_masala_munch_90g`) and is unique across the whole catalogue,
+// which is exactly what the bare catalogueid is not.
+func (r *productRepository) FindTenantProductByImageID(tenantid int, imageid string) (*models.Products, error) {
+	if strings.TrimSpace(imageid) == "" {
+		return nil, nil
+	}
+	var product models.Products
+	result := r.db.Table("products").
+		Where("tenantid = ? AND imageid = ?", tenantid, imageid).
+		First(&product)
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+			return nil, nil
+		}
+		return nil, result.Error
+	}
+	return &product, nil
+}
+
+// SetCatalogueLink repairs one product's pointer back into the catalogue.
+//
+// Both halves move together and both can be cleared, which is the point.
+// `imageid` is what a product should be linked by from now on; a `catalogueid`
+// of 0 marks a link that could not be repaired at all — the row it named is
+// gone and the re-scrape left nothing matching behind it. Clearing it is not
+// data loss: the pointer already pointed at nothing, and leaving it in place
+// makes a browse screen claim the product is imported from a row that does not
+// exist, and makes re-importing fail outright.
+func (r *productRepository) SetCatalogueLink(productid int, imageid string, catalogueid int) error {
+	return r.db.Table("products").
+		Where("productid = ?", productid).
+		Updates(map[string]any{"imageid": imageid, "catalogueid": catalogueid}).Error
+}
+
+// ListCatalogueLinkedProducts returns every product of a tenant that claims to
+// have come from the catalogue, so each claim can be checked.
+func (r *productRepository) ListCatalogueLinkedProducts(tenantid int) ([]models.Products, error) {
+	products := make([]models.Products, 0)
+	err := r.db.Table("products").
+		Where("tenantid = ? AND catalogueid IS NOT NULL AND catalogueid != 0", tenantid).
+		Find(&products).Error
+	return products, err
+}
+
 // GetImportedCatalogueRefs returns the (brand, catalogueid) pairs this
 // tenant has already imported, so a catalogue browse screen can mark items
 // as already-imported without diffing full product lists client-side. Brand
@@ -1225,7 +1282,7 @@ func (r *productRepository) CreateProductReturningID(product models.Products) (i
 func (r *productRepository) GetImportedCatalogueRefs(tenantid int, brand string) ([]models.ImportedCatalogueRef, error) {
 	refs := make([]models.ImportedCatalogueRef, 0)
 	query := r.db.Table("products").
-		Select("productbrand AS brand, catalogueid").
+		Select("productbrand AS brand, catalogueid, COALESCE(imageid, '') AS imageid").
 		Where("tenantid = ? AND catalogueid IS NOT NULL AND catalogueid != 0", tenantid)
 	if brand != "" {
 		query = query.Where("productbrand = ?", brand)
@@ -1289,9 +1346,9 @@ func (r *productRepository) UpdateProductCategory(productid, categoryid, subcate
 // than three unrelated products — and until now it could only ever be set at
 // CREATE time, by a caller that already knew the group id:
 //
-//   products/create           writes whatever the body carries, variants included
-//   importcatalogueproduct    never sets it, so every imported product is 0
-//   UpdateProduct             writes productlocations.status only, despite the name
+//	products/create           writes whatever the body carries, variants included
+//	importcatalogueproduct    never sets it, so every imported product is 0
+//	UpdateProduct             writes productlocations.status only, despite the name
 //
 // Since importing from the catalogue is how products actually arrive, every
 // product this console creates is ungrouped and there was no call that could