From 10e5e6d6235dd4fdd39224f940f981dcb60aed06 Mon Sep 17 00:00:00 2001
From: Frederik Rommel <15031079+rommelfreddy@users.noreply.github.com>
Date: Mon, 5 Sep 2022 11:33:31 +0200
Subject: [PATCH] fix: installment: fix calculation of getAllowedMoth on
 ConfigurationRequest (#29)

getAllowedMoth has a legacy calculation of the monthly rate, so the results are not correctly on threshold values.
It has been replace with the offline-calculation-request, so it is the same calculation.
---
 src/Model/Response/ConfigurationRequest.php   | 33 +++++++++++--------
 .../Response/ConfigurationRequestTest.php     |  2 ++
 2 files changed, 22 insertions(+), 13 deletions(-)

diff --git a/src/Model/Response/ConfigurationRequest.php b/src/Model/Response/ConfigurationRequest.php
index 7cc1c59..5e1bba0 100644
--- a/src/Model/Response/ConfigurationRequest.php
+++ b/src/Model/Response/ConfigurationRequest.php
@@ -9,6 +9,9 @@
 
 namespace RatePAY\Model\Response;
 
+    use RatePAY\ModelBuilder;
+    use RatePAY\Service\OfflineInstallmentCalculation;
+
     class ConfigurationRequest extends AbstractResponse
     {
         /**
@@ -44,30 +47,34 @@ public function validateResponse()
          * Returns allowed months. If order amount is entered it returns only admitted month for specific order amount.
          *
          * @param float $orderAmount
+         * @param float $paymentFirstDay
          *
          * @return array
          */
-        public function getAllowedMonths($orderAmount = 0)
+        public function getAllowedMonths($orderAmount = 0, $paymentFirstDay = null)
         {
             if ($orderAmount == 0) {
                 return $this->result['monthAllowed'];
             }
 
-            $allowedMonths = $this->result['monthAllowed'];
             $possibleMonths = [];
 
-            $rateMinNormal = $this->result['rateMinNormal'];
-            $interestRate = $this->result['interestRateDefault'] / 100;
-            $interestRateMonth = $interestRate / 12;
+            foreach ($this->result['monthAllowed'] as $runtime) {
+                $mbContent = new ModelBuilder('Content');
+                $mbContent->setArray([
+                    'InstallmentCalculation' => [
+                        'Amount' => $orderAmount,
+                        'PaymentFirstday' => $paymentFirstDay ? $paymentFirstDay : $this->result['paymentFirstday'],
+                        'InterestRate' => $this->result['interestRateDefault'],
+                        'ServiceCharge' => $this->result['serviceCharge'],
+                        'CalculationTime' => [
+                            'Month' => $runtime,
+                        ],
+                    ],
+                ]);
 
-            foreach ($allowedMonths as $runtime) {
-                if ($interestRate > 0) {
-                    $rateAmount = $orderAmount * (($interestRateMonth * pow((1 + $interestRateMonth), $runtime)) / (pow((1 + $interestRateMonth), $runtime) - 1));
-                } else {
-                    $rateAmount = $orderAmount / $runtime;
-                }
-                $rateAmount = ceil($rateAmount);
-                if ($rateAmount >= $rateMinNormal) {
+                $monthlyRate = (new OfflineInstallmentCalculation())->callOfflineCalculation($mbContent)->subtype('calculation-by-time');
+                if ($monthlyRate >= $this->result['rateMinNormal']) {
                     $possibleMonths[] = $runtime;
                 }
             }
diff --git a/tests/Unit/Model/Response/ConfigurationRequestTest.php b/tests/Unit/Model/Response/ConfigurationRequestTest.php
index 4e17474..3cea17b 100644
--- a/tests/Unit/Model/Response/ConfigurationRequestTest.php
+++ b/tests/Unit/Model/Response/ConfigurationRequestTest.php
@@ -21,6 +21,8 @@ public function testGetAllowedMonths($amount, $expectedAllowedMonths)
             'monthAllowed' => [3, 6, 9, 12, 18, 24, 36],
             'rateMinNormal' => 20.0,
             'interestRateDefault' => 13.7,
+            'paymentFirstday' => 2,
+            'serviceCharge' => 0
         ]);
 
         $allowedMonths = $response->getAllowedMonths($amount);