import type TrackPurchaseParameters from '../models/TrackPurchaseParameters';

export default class TrackPurchaseParametersUtil {
  /**
   * Returns the names of the fields required for Shopping V2 purchase
   * tracking parity with Web that are missing from `parameters`.
   *
   * Required fields: orderId, value (order_value), currencyCode (currency),
   * subtotal, and a non-empty products list (line_items) where every product
   * has a non-empty sku or extProductId.
   */
  static missingRequiredV2Fields(
    parameters?: TrackPurchaseParameters | null
  ): string[] {
    if (!parameters) {
      return ['parameters'];
    }

    const missing: string[] = [];
    if (!parameters.orderId) {
      missing.push('orderId');
    }
    if (typeof parameters.value !== 'number') {
      missing.push('value');
    }
    if (!parameters.currencyCode) {
      missing.push('currencyCode');
    }
    if (typeof parameters.subtotal !== 'number') {
      missing.push('subtotal');
    }

    const products = parameters.products;
    if (!products || products.length === 0) {
      missing.push('products');
    } else {
      products.forEach((product, index) => {
        if (!product.sku && !product.extProductId) {
          missing.push(`products[${index}].sku`);
        }
      });
    }
    return missing;
  }
}