From 14902a4b68731172f8a0a140816700af195a13b5 Mon Sep 17 00:00:00 2001
From: Lukasz Ostrowski <lukasz.ostrowski@saleor.io>
Date: Sun, 15 Dec 2024 18:37:55 +0100
Subject: [PATCH] log suspicious taxes calculation

---
 .changeset/six-lamps-shop.md                          |  5 +++++
 .../calculate-taxes/avatax-calculate-taxes-adapter.ts | 11 +++++++++++
 .../pages/api/webhooks/checkout-calculate-taxes.ts    |  1 +
 3 files changed, 17 insertions(+)
 create mode 100644 .changeset/six-lamps-shop.md

diff --git a/.changeset/six-lamps-shop.md b/.changeset/six-lamps-shop.md
new file mode 100644
index 000000000..1f7973d51
--- /dev/null
+++ b/.changeset/six-lamps-shop.md
@@ -0,0 +1,5 @@
+---
+"app-avatax": patch
+---
+
+Add log when suspicious calculation happen - when line tax rate is non-zero but amount of taxes is zero
diff --git a/apps/avatax/src/modules/avatax/calculate-taxes/avatax-calculate-taxes-adapter.ts b/apps/avatax/src/modules/avatax/calculate-taxes/avatax-calculate-taxes-adapter.ts
index 4f5cd3dab..c9f8b49b5 100644
--- a/apps/avatax/src/modules/avatax/calculate-taxes/avatax-calculate-taxes-adapter.ts
+++ b/apps/avatax/src/modules/avatax/calculate-taxes/avatax-calculate-taxes-adapter.ts
@@ -37,6 +37,17 @@ export class AvataxCalculateTaxesAdapter {
 
       const transformedResponse = this.avataxCalculateTaxesResponseTransformer.transform(response);
 
+      transformedResponse.lines.forEach((l) => {
+        const tax = (l.total_gross_amount = l.total_net_amount);
+        const rate = l.tax_rate;
+
+        if (tax === 0 && rate !== 0) {
+          this.logger.warn("Line has zero tax, but rate is not zero", {
+            taxCalculationSummary: response.summary,
+          });
+        }
+      });
+
       this.logger.debug("Transformed AvaTax createTransaction response");
 
       return transformedResponse;
diff --git a/apps/avatax/src/pages/api/webhooks/checkout-calculate-taxes.ts b/apps/avatax/src/pages/api/webhooks/checkout-calculate-taxes.ts
index 39a6f1579..98d7e4af5 100644
--- a/apps/avatax/src/pages/api/webhooks/checkout-calculate-taxes.ts
+++ b/apps/avatax/src/pages/api/webhooks/checkout-calculate-taxes.ts
@@ -31,6 +31,7 @@ const handler = checkoutCalculateTaxesSyncWebhook.createHandler(async (req, res,
 
   /**
    * Create deps in handler, so it's potentially faster and reduce lambda start
+   * TODO: It's rather not true, we should move it outside
    */
   const subscriptionErrorChecker = new SubscriptionPayloadErrorChecker(logger, captureException);
   const useCase = new CalculateTaxesUseCase({