feat(purchase): unwired unit convertions

internal/processor/purchase_order_processor.go

@@ -32,6 +32,9 @@ type PurchaseOrderProcessorImpl struct {
 	categoryRepo             CategoryRepository
 	unitRepo                 UnitRepository
 	fileRepo                 FileRepository
+	// Kept wired but currently unused: purchase orders are a record of spending
+	// only, so nothing here moves stock or converts units. These stay so that
+	// tying purchases back to inventory is a change in one place.
 	inventoryMovementService InventoryMovementService
 	unitConverterRepo        IngredientUnitConverterRepository
 }
@@ -438,73 +441,11 @@ func (p *PurchaseOrderProcessorImpl) UpdatePurchaseOrderStatus(ctx context.Conte
 
 	fmt.Println("status:", po.Status)
 
-	// Check if status is changing to "received" and current status is not "received"
-	if status == "received" && po.Status != "received" {
-		// Get purchase order with items for inventory update
-		poWithItems, err := p.purchaseOrderRepo.GetByID(ctx, id)
-		if err != nil {
-			return nil, fmt.Errorf("failed to get purchase order with items: %w", err)
-		}
-
-		// Update inventory for each item
-		for _, item := range poWithItems.Items {
-			if item.PurchaseCategory != nil && item.PurchaseCategory.Type == entities.PurchaseCategoryTypeExpense {
-				continue
-			}
-
-			if item.IngredientID == nil || item.UnitID == nil || item.Quantity == nil {
-				return nil, fmt.Errorf("purchase order item %s is missing raw material inventory fields", item.ID)
-			}
-
-			// Get ingredient to find its base unit
-			ingredient, err := p.ingredientRepo.GetByID(ctx, *item.IngredientID, organizationID)
-			if err != nil {
-				return nil, fmt.Errorf("failed to get ingredient %s: %w", *item.IngredientID, err)
-			}
-
-			// Convert quantity to ingredient's base unit if needed. An ingredient
-			// without a unit has no base unit to convert into, so the purchased
-			// quantity is taken as-is.
-			quantityToAdd := *item.Quantity
-			if ingredient.UnitID != nil && *item.UnitID != *ingredient.UnitID {
-				// Convert from purchase unit to ingredient's base unit
-				convertedQuantity, err := p.unitConverterRepo.ConvertQuantity(ctx, *item.IngredientID, *item.UnitID, *ingredient.UnitID, organizationID, *item.Quantity)
-				if err != nil {
-					return nil, fmt.Errorf("failed to convert quantity for ingredient %s from unit %s to %s: %w", *item.IngredientID, *item.UnitID, *ingredient.UnitID, err)
-				}
-				quantityToAdd = convertedQuantity
-			}
-
-			// Calculate unit cost in ingredient's base unit
-			unitCost := 0.0
-			if quantityToAdd > 0 {
-				unitCost = calculatePurchaseOrderItemTotal(item.Quantity, item.Amount) / quantityToAdd
-			}
-
-			// Create inventory movement for ingredient purchase
-			reason := fmt.Sprintf("Purchase order %s received", po.PONumber)
-			referenceType := entities.InventoryMovementReferenceTypePurchaseOrder
-			referenceID := &id
-
-			err = p.inventoryMovementService.CreateIngredientMovement(
-				ctx,
-				*item.IngredientID,
-				organizationID,
-				outletID,
-				userID,
-				entities.InventoryMovementTypePurchase,
-				quantityToAdd,
-				unitCost,
-				reason,
-				&referenceType,
-				referenceID,
-				&item.ID,
-			)
-			if err != nil {
-				return nil, fmt.Errorf("failed to create inventory movement for ingredient %s: %w", *item.IngredientID, err)
-			}
-		}
-	}
+	// A purchase order is a record of spending only. Receiving one does not move
+	// ingredient stock, does not recalculate ingredient cost, and never converts
+	// units: the quantity and unit on an item are kept exactly as the user
+	// entered them. Raw material items are therefore treated the same way expense
+	// items already were, and the ingredient on an item is just a reference.
 
 	// Update the purchase order status
 	statusOutletID := po.OutletID