refactoring

packages/domain/value-objects/CheckoutPrice.ts

@@ -10,7 +10,7 @@ export class CheckoutPrice {
 
   static fromString(priceStr: string): CheckoutPrice {
     const trimmed = priceStr.trim();
-    
+
     if (!trimmed.startsWith('$')) {
       throw new Error('Invalid price format: missing dollar sign');
     }
@@ -21,13 +21,13 @@ export class CheckoutPrice {
     }
 
     const numericPart = trimmed.substring(1).replace(/,/g, '');
-    
+
     if (numericPart === '') {
       throw new Error('Invalid price format: no numeric value');
     }
 
     const amount = parseFloat(numericPart);
-    
+
     if (isNaN(amount)) {
       throw new Error('Invalid price format: not a valid number');
     }
@@ -35,6 +35,14 @@ export class CheckoutPrice {
     return new CheckoutPrice(amount);
   }
 
+  /**
+   * Factory for a neutral/zero checkout price.
+   * Used when no explicit price can be extracted from the DOM.
+   */
+  static zero(): CheckoutPrice {
+    return new CheckoutPrice(0);
+  }
+
   toDisplayString(): string {
     return `$${this.amountUsd.toFixed(2)}`;
   }