ACP2E-2651: Incorrect subtotal in order when FPT is used

Author: veloraven

app/code/Magento/Weee/Model/Total/Invoice/Weee.php

@@ -174,6 +174,18 @@ public function collect(\Magento\Sales\Model\Order\Invoice $invoice)
             $baseTotalWeeeAmountInclTax += $baseWeeeAmountInclTax;
         }
 
+        // If FPT is configured to be included in the subtotal,
+        // we need to subtract it from the subtotal and the grand total,
+        // as Collect function from Catalog module knows nothing about FPT and that it is already included in Subtotal
+        if ($invoice->isLast() && $this->_weeeData->includeInSubtotal($store)) {
+            $invoice->setSubtotal($invoice->getSubtotal() - $totalWeeeAmount);
+            $invoice->setBaseSubtotal($invoice->getBaseSubtotal() - $baseTotalWeeeAmount);
+            $invoice->setGrandTotal($invoice->getGrandTotal() - $totalWeeeAmountInclTax);
+            $invoice->setBaseGrandTotal($invoice->getBaseGrandTotal() - $baseTotalWeeeAmountInclTax);
+            $invoice->setTaxAmount($invoice->getTaxAmount() - $totalWeeeTaxAmount);
+            $invoice->setBaseTaxAmount($invoice->getBaseTaxAmount() - $baseTotalWeeeTaxAmount);
+        }
+
         $allowedTax = $order->getTaxAmount() - $order->getTaxInvoiced() - $invoice->getTaxAmount();
         $allowedBaseTax = $order->getBaseTaxAmount() - $order->getBaseTaxInvoiced() - $invoice->getBaseTaxAmount();
         $totalWeeeTaxAmount = min($totalWeeeTaxAmount, $allowedTax);
@@ -200,7 +212,6 @@ public function collect(\Magento\Sales\Model\Order\Invoice $invoice)
             // need to add the Weee amounts including all their taxes
             $invoice->setSubtotalInclTax($invoice->getSubtotalInclTax() + $totalWeeeAmountInclTax);
             $invoice->setBaseSubtotalInclTax($invoice->getBaseSubtotalInclTax() + $baseTotalWeeeAmountInclTax);
-        } else {
             // since the Subtotal Incl Tax line will already have the taxes on Weee, just add the non-taxable amounts
             $invoice->setSubtotalInclTax($invoice->getSubtotalInclTax() + $totalWeeeAmount);
             $invoice->setBaseSubtotalInclTax($invoice->getBaseSubtotalInclTax() + $baseTotalWeeeAmount);