From 624cc8e5f5539f0a39d6b5a725c49b6a744d8840 Mon Sep 17 00:00:00 2001
From: Eduardo Iriarte-Mendez <eduardo.iriarte-mendez@ratepay.com>
Date: Tue, 1 Feb 2022 13:37:52 +0100
Subject: [PATCH] feat: reorganize offline inst-calculation

- implement unit-tests
- add DateTime wrapper
- throw proper exceptions

ORCA-1973

Squashed commit of the following:

commit d9038a95afac8c972e593daa7e6234da0f382647
Author: Eduardo Iriarte-Mendez <eduardo.iriarte-mendez@ratepay.com>
Date:   Fri Jan 28 18:11:50 2022 +0100

    feat: reorganize offline inst-calculation

    - implement unit-tests
    - add DateTime wrapper
    - throw proper exceptions
---
 .../OfflineInstalmentCalculationException.php |  18 +++
 src/Service/DateTime/DateTime.php             |  43 ++++++
 src/Service/DateTime/DateTimeCalculators.php  |  57 ++++++++
 src/Service/DateTime/DateTimeModifiers.php    | 101 +++++++++++++
 src/Service/DateTime/DateTimeTesting.php      |  61 ++++++++
 src/Service/Math.php                          |  16 ++
 src/Service/OfflineInstallmentCalculation.php |  73 +++------
 tests/Unit/Service/DateTimeTest.php           |  95 ++++++++++++
 tests/Unit/Service/MathTest.php               |  24 +++
 .../OfflineInstallmentCalculationTest.php     | 138 +++++++++++++++++-
 10 files changed, 572 insertions(+), 54 deletions(-)
 create mode 100644 src/Exception/OfflineInstalmentCalculationException.php
 create mode 100644 src/Service/DateTime/DateTime.php
 create mode 100644 src/Service/DateTime/DateTimeCalculators.php
 create mode 100644 src/Service/DateTime/DateTimeModifiers.php
 create mode 100644 src/Service/DateTime/DateTimeTesting.php
 create mode 100644 tests/Unit/Service/DateTimeTest.php

diff --git a/src/Exception/OfflineInstalmentCalculationException.php b/src/Exception/OfflineInstalmentCalculationException.php
new file mode 100644
index 0000000..eae5354
--- /dev/null
+++ b/src/Exception/OfflineInstalmentCalculationException.php
@@ -0,0 +1,18 @@
+<?php
+
+/*
+ * Ratepay PHP-Library
+ *
+ * This document contains trade secret data which are the property of
+ * Ratepay GmbH, Berlin, Germany. Information contained herein must not be used,
+ * copied or disclosed in whole or part unless permitted in writing by Ratepay GmbH.
+ * All rights reserved by Ratepay GmbH.
+ *
+ * Copyright (c) 2019 Ratepay GmbH / Berlin / Germany
+ */
+
+namespace RatePAY\Exception;
+
+class OfflineInstalmentCalculationException extends \Exception
+{
+}
diff --git a/src/Service/DateTime/DateTime.php b/src/Service/DateTime/DateTime.php
new file mode 100644
index 0000000..29e8385
--- /dev/null
+++ b/src/Service/DateTime/DateTime.php
@@ -0,0 +1,43 @@
+<?php
+
+/*
+ * Ratepay PHP-Library
+ *
+ * This document contains trade secret data which are the property of
+ * Ratepay GmbH, Berlin, Germany. Information contained herein must not be used,
+ * copied or disclosed in whole or part unless permitted in writing by Ratepay GmbH.
+ * All rights reserved by Ratepay GmbH.
+ *
+ * Copyright (c) 2019 Ratepay GmbH / Berlin / Germany
+ */
+
+namespace RatePAY\Service\DateTime;
+
+use DateTime as InternalDateTime;
+
+/**
+ * DateTime wrapper class inspired by Carbon.
+ * It provides handy accessors and allow isolation of internal classes during testing.
+ */
+class DateTime extends InternalDateTime
+{
+    use DateTimeTesting;
+    use DateTimeModifiers;
+    use DateTimeCalculators;
+
+    /**
+     * @return DateTime
+     */
+    public static function now()
+    {
+        return self::hasTestingNow() ? self::getTestingNow() : new DateTime();
+    }
+
+    /**
+     * @return DateTime
+     */
+    public static function today()
+    {
+        return self::hasTestingNow() ? self::getTestingNow()->setTime(0, 0) : new DateTime('today');
+    }
+}
diff --git a/src/Service/DateTime/DateTimeCalculators.php b/src/Service/DateTime/DateTimeCalculators.php
new file mode 100644
index 0000000..9f06e80
--- /dev/null
+++ b/src/Service/DateTime/DateTimeCalculators.php
@@ -0,0 +1,57 @@
+<?php
+
+/*
+ * Ratepay PHP-Library
+ *
+ * This document contains trade secret data which are the property of
+ * Ratepay GmbH, Berlin, Germany. Information contained herein must not be used,
+ * copied or disclosed in whole or part unless permitted in writing by Ratepay GmbH.
+ * All rights reserved by Ratepay GmbH.
+ *
+ * Copyright (c) 2019 Ratepay GmbH / Berlin / Germany
+ */
+
+namespace RatePAY\Service\DateTime;
+
+trait DateTimeCalculators
+{
+    /**
+     * @param DateTime $dateTime related date time to perform calculation
+     *
+     * @return int|float difference between dates in seconds
+     */
+    public function diffInSeconds($dateTime)
+    {
+        return $this->getTimestamp() - $dateTime->getTimestamp();
+    }
+
+    /**
+     * @param DateTime $dateTime related date time to perform calculation
+     *
+     * @return int|float difference between dates in minutes
+     */
+    public function diffInMinutes($dateTime)
+    {
+        return $this->diffInSeconds($dateTime) / 60;
+    }
+
+    /**
+     * @param DateTime $dateTime related date time to perform calculation
+     *
+     * @return int|float difference between dates in minutes
+     */
+    public function diffInHours($dateTime)
+    {
+        return $this->diffInMinutes($dateTime) / 60;
+    }
+
+    /**
+     * @param DateTime $dateTime related date time to perform calculation
+     *
+     * @return int|float difference between dates in minutes
+     */
+    public function diffInDays($dateTime)
+    {
+        return $this->diffInHours($dateTime) / 24;
+    }
+}
diff --git a/src/Service/DateTime/DateTimeModifiers.php b/src/Service/DateTime/DateTimeModifiers.php
new file mode 100644
index 0000000..181d0cb
--- /dev/null
+++ b/src/Service/DateTime/DateTimeModifiers.php
@@ -0,0 +1,101 @@
+<?php
+
+/*
+ * Ratepay PHP-Library
+ *
+ * This document contains trade secret data which are the property of
+ * Ratepay GmbH, Berlin, Germany. Information contained herein must not be used,
+ * copied or disclosed in whole or part unless permitted in writing by Ratepay GmbH.
+ * All rights reserved by Ratepay GmbH.
+ *
+ * Copyright (c) 2019 Ratepay GmbH / Berlin / Germany
+ */
+
+namespace RatePAY\Service\DateTime;
+
+trait DateTimeModifiers
+{
+    /**
+     * @param int $day days of month to set
+     *
+     * @return DateTime
+     */
+    public function setDay($day)
+    {
+        $date = $this->getDateFields();
+
+        return $this->setDate($date->year, $date->month, $day);
+    }
+
+    /**
+     * @param int $daysOffset number of days to be added
+     *
+     * @return DateTime
+     */
+    public function addDays($daysOffset)
+    {
+        $date = $this->getDateFields();
+
+        return $this->setDate($date->year, $date->month, $date->day + $daysOffset);
+    }
+
+    /**
+     * @param int $month month of year to set
+     *
+     * @return DateTime
+     */
+    public function setMonth($month)
+    {
+        $date = $this->getDateFields();
+
+        return $this->setDate($date->year, $month, $date->day);
+    }
+
+    /**
+     * @param int $monthsOffset number of months to be added
+     *
+     * @return DateTime
+     */
+    public function addMonths($monthsOffset)
+    {
+        $date = $this->getDateFields();
+
+        return $this->setDate($date->year, $date->month + $monthsOffset, $date->day);
+    }
+
+    /**
+     * @param int $year year to set
+     *
+     * @return DateTime
+     */
+    public function setYear($year)
+    {
+        $date = $this->getDateFields();
+
+        return $this->setDate($year, $date->month, $date->day);
+    }
+
+    /**
+     * @param int $yearsOffset number of years to be added
+     *
+     * @return DateTime
+     */
+    public function addYears($yearsOffset)
+    {
+        $date = $this->getDateFields();
+
+        return $this->setDate($date->year + $yearsOffset, $date->month, $date->day);
+    }
+
+    /**
+     * @return object
+     */
+    private function getDateFields()
+    {
+        return (object) [
+            'year' => (int) $this->format('Y'),
+            'month' => (int) $this->format('m'),
+            'day' => (int) $this->format('d'),
+        ];
+    }
+}
diff --git a/src/Service/DateTime/DateTimeTesting.php b/src/Service/DateTime/DateTimeTesting.php
new file mode 100644
index 0000000..0cca32d
--- /dev/null
+++ b/src/Service/DateTime/DateTimeTesting.php
@@ -0,0 +1,61 @@
+<?php
+
+/*
+ * Ratepay PHP-Library
+ *
+ * This document contains trade secret data which are the property of
+ * Ratepay GmbH, Berlin, Germany. Information contained herein must not be used,
+ * copied or disclosed in whole or part unless permitted in writing by Ratepay GmbH.
+ * All rights reserved by Ratepay GmbH.
+ *
+ * Copyright (c) 2019 Ratepay GmbH / Berlin / Germany
+ */
+
+namespace RatePAY\Service\DateTime;
+
+trait DateTimeTesting
+{
+    /**
+     * @var DateTime
+     */
+    private static $_testingNow;
+
+    /**
+     * It sets a custom DateTime instance as the "now" value.
+     * This handy hook allows performing tests without side effects.
+     *
+     * @return DateTime
+     */
+    public static function withTestingNow(DateTime $dateTime)
+    {
+        self::$_testingNow = $dateTime;
+
+        return self::now();
+    }
+
+    /**
+     * It restores testing now to empty value and allows normal DateTime functionality.
+     *
+     * @return void
+     */
+    public static function resetTestingNow()
+    {
+        self::$_testingNow = null;
+    }
+
+    /**
+     * @return bool
+     */
+    private static function hasTestingNow()
+    {
+        return isset(self::$_testingNow);
+    }
+
+    /**
+     * @return DateTime
+     */
+    private static function getTestingNow()
+    {
+        return clone self::$_testingNow;
+    }
+}
diff --git a/src/Service/Math.php b/src/Service/Math.php
index b4d3db0..0e9f1b9 100644
--- a/src/Service/Math.php
+++ b/src/Service/Math.php
@@ -18,6 +18,11 @@
  */
 class Math
 {
+    public static function isZero($number, $precission = 2)
+    {
+        return round($number, $precission) === 0.0;
+    }
+
     /**
      * @param float     $netPrice
      * @param float|int $taxPercentage
@@ -37,4 +42,15 @@ public static function netToGross($netPrice, $taxPercentage, $round = false)
 
         return $rounded;
     }
+
+    /**
+     * @param float $annualInterestRate annual percentage interest rate
+     * @param float $interval           Fraction of a year
+     *
+     * @return float|int
+     */
+    public static function interestByInterval($annualInterestRate, $interval)
+    {
+        return pow((1 + ($annualInterestRate / 100)), $interval) - 1;
+    }
 }
diff --git a/src/Service/OfflineInstallmentCalculation.php b/src/Service/OfflineInstallmentCalculation.php
index e7a96fb..744f9f7 100644
--- a/src/Service/OfflineInstallmentCalculation.php
+++ b/src/Service/OfflineInstallmentCalculation.php
@@ -13,8 +13,10 @@
 
 namespace RatePAY\Service;
 
+use RatePAY\Exception\OfflineInstalmentCalculationException;
 use RatePAY\Exception\RequestException;
 use RatePAY\ModelBuilder as ModelBuilder;
+use RatePAY\Service\DateTime\DateTime;
 
 /**
  * Class OfflineInstallmentCalculation.
@@ -107,60 +109,33 @@ public function subtype($subtype)
      */
     private function callCalculationByTime()
     {
-        $datePaymentFirstday = mktime(0, 0, 0, $this->_paymentFirstday == 28 ? (int) date('m') + 1 : (int) date('m') + 2, $this->_paymentFirstday, date('Y'));
-        $today = time();
-        $difference = $datePaymentFirstday - $today;
-
-        $daysTillPaymentFirstday = ceil($difference / 60 / 60 / 24) + 1;
-
-        $interestRateMonth =
-            pow(
-                (1 + ($this->_interestRate / 100)),
-                (1 / 12)
-            )
-            -
-            1;
-
-        $interestRateTillStart =
-            pow(
-                (($this->_interestRate / 100) + 1),
-                ($daysTillPaymentFirstday / 365)
-            )
-            -
-            1;
-
-        $installment =
-            (
-                $this->_basketAmount
-                *
-                (1 + ($interestRateTillStart))
-                *
-                $interestRateMonth
-                *
-                pow(
-                    (1 + $interestRateMonth),
-                    ($this->_runtime - 1)
-                )
-            )
-            /
-            (
-                pow(
-                    (1 + $interestRateMonth),
-                    ($this->_runtime)
-                )
-                -
-                1
-            )
-            +
-            ($this->_serviceCharge / $this->_runtime);
-
-        return round($installment, 2);
+        $totalMonths = (int) ($this->_runtime ?: 0);
+
+        if ($totalMonths === 0) {
+            throw new OfflineInstalmentCalculationException('Runtime of 0 months not allowed.');
+        }
+
+        $daysUntilFirstDueDate = DateTime::today()
+            ->addMonths($this->_paymentFirstday == 28 ? 1 : 2)
+            ->setDay($this->_paymentFirstday + 1)
+            ->diffInDays(DateTime::today());
+        $monthlyInterestRate = Math::interestByInterval($this->_interestRate, (1 / 12));
+        $interestRateUntilFirstDue = Math::interestByInterval($this->_interestRate, ($daysUntilFirstDueDate / 365));
+        $interestRateProduct = pow((1 + $monthlyInterestRate), $totalMonths) - 1;
+        $monthlyServiceCharge = $this->_serviceCharge / $totalMonths;
+        $paymentStreamFactor = $this->_basketAmount * (1 + $interestRateUntilFirstDue) * $monthlyInterestRate;
+
+        $monthlyInstalment = ($paymentStreamFactor / $interestRateProduct)
+            * pow((1 + $monthlyInterestRate), ($totalMonths - 1))
+            + $monthlyServiceCharge;
+
+        return round($monthlyInstalment, 2);
     }
 
     private function callZeroPercentCalculationByTime()
     {
         if ((int) $this->_runtime === 0) {
-            throw new \Exception('Runtime of 0 months not allowed.');
+            throw new OfflineInstalmentCalculationException('Runtime of 0 months not allowed.');
         }
 
         $monthlyInstalment = $this->_basketAmount / $this->_runtime;
diff --git a/tests/Unit/Service/DateTimeTest.php b/tests/Unit/Service/DateTimeTest.php
new file mode 100644
index 0000000..6d1cb22
--- /dev/null
+++ b/tests/Unit/Service/DateTimeTest.php
@@ -0,0 +1,95 @@
+<?php
+
+namespace RatePAY\Tests\Unit\Service;
+
+use PHPUnit\Framework\TestCase;
+use RatePAY\Service\DateTime\DateTime;
+
+class DateTimeTest extends TestCase
+{
+    /** @dataProvider provideFakeNow */
+    public function testNow($now, $expectedDate, $format)
+    {
+        DateTime::withTestingNow(new DateTime($now));
+
+        $dateTime = DateTime::now();
+
+        DateTime::resetTestingNow();
+
+        $this->assertEquals($expectedDate, $dateTime->format($format));
+    }
+
+    public function provideFakeNow()
+    {
+        return [
+            ['2020-01-10T10:32:57+01:00', '2020-01-10', 'Y-m-d'],
+            ['2018-05-10T17:32:23+00:00', '2018-05-10 17:32:23', 'Y-m-d H:i:s'],
+            ['yesterday', (new \DateTime('yesterday'))->format('Y-m-d'), 'Y-m-d'],
+        ];
+    }
+
+    /** @dataProvider provideFakeToday */
+    public function testToday($now, $expectedDate, $format)
+    {
+        DateTime::withTestingNow(new DateTime($now));
+
+        $dateTime = DateTime::today();
+
+        DateTime::resetTestingNow();
+
+        $this->assertEquals($expectedDate, $dateTime->format($format));
+    }
+
+    public function provideFakeToday()
+    {
+        return [
+            ['2020-01-10T10:32:57+01:00', '2020-01-10', 'Y-m-d'],
+            ['2018-05-10T17:32:23+00:00', '2018-05-10 00:00:00', 'Y-m-d H:i:s'],
+            ['yesterday', (new \DateTime('yesterday'))->format('Y-m-d H:i:s'), 'Y-m-d H:i:s'],
+        ];
+    }
+
+    /** @dataProvider provideAddDayTransformations */
+    public function testAddDayTransformation($now, $days, $expectedDate)
+    {
+        DateTime::withTestingNow(new DateTime($now));
+
+        $dateTime = DateTime::now()->addDays($days);
+
+        DateTime::resetTestingNow();
+
+        $this->assertEquals($expectedDate, $dateTime->format('Y-m-d H:i:s'));
+    }
+
+    public function provideAddDayTransformations()
+    {
+        return [
+            ['2020-01-10T10:32:57+01:00', 5, '2020-01-15 10:32:57'],
+            ['2020-02-27T17:32:23+00:00', 3, '2020-03-01 17:32:23'],
+            ['2019-02-27T17:32:23+00:00', 3, '2019-03-02 17:32:23'],
+            ['2019-02-27T17:32:23+00:00', -3, '2019-02-24 17:32:23'],
+        ];
+    }
+
+    /** @dataProvider provideAddMonthTransformations */
+    public function testAddMonthTransformation($now, $months, $expectedDate)
+    {
+        DateTime::withTestingNow(new DateTime($now));
+
+        $dateTime = DateTime::now()->addMonths($months);
+
+        DateTime::resetTestingNow();
+
+        $this->assertEquals($expectedDate, $dateTime->format('Y-m-d H:i:s'));
+    }
+
+    public function provideAddMonthTransformations()
+    {
+        return [
+            ['2020-01-10T10:32:57+01:00', 5, '2020-06-10 10:32:57'],
+            ['2020-11-27T17:32:23+00:00', 3, '2021-02-27 17:32:23'],
+            ['2019-11-27T17:32:23+00:00', -3, '2019-08-27 17:32:23'],
+            ['2019-02-27T17:32:23+00:00', -3, '2018-11-27 17:32:23'],
+        ];
+    }
+}
diff --git a/tests/Unit/Service/MathTest.php b/tests/Unit/Service/MathTest.php
index edf73b5..26d49f4 100644
--- a/tests/Unit/Service/MathTest.php
+++ b/tests/Unit/Service/MathTest.php
@@ -50,4 +50,28 @@ public function provideRoundedNatPricesWithTaxRates()
             [29.99, 2.5, 30.74],
         ];
     }
+
+    /** @dataProvider provideZeroValues */
+    public function testIsZero($number, $precission, $expectation)
+    {
+        $isZero = Math::isZero($number, $precission);
+
+        $this->assertEquals($expectation, $isZero);
+    }
+
+    public function provideZeroValues()
+    {
+        return [
+            [ -0.000001, 0, true ],
+            [ -0.000001, 1, true ],
+            [ -0.000001, 2, true ],
+            [ -0.000001, 3, true ],
+            [ -0.000001, 4, true ],
+            [ -0.000001, 5, true ],
+            [ -0.000001, 6, false ],
+            [ -0.3 + 0.09 + 0.2, 0, true ],
+            [ -0.3 + 0.09 + 0.2, 1, true ],
+            [ -0.3 + 0.09 + 0.2, 2, false ],
+        ];
+    }
 }
diff --git a/tests/Unit/Service/OfflineInstallmentCalculationTest.php b/tests/Unit/Service/OfflineInstallmentCalculationTest.php
index 90fcfd7..212a3b0 100644
--- a/tests/Unit/Service/OfflineInstallmentCalculationTest.php
+++ b/tests/Unit/Service/OfflineInstallmentCalculationTest.php
@@ -10,17 +10,95 @@
 
 use PHPUnit\Framework\TestCase;
 use RatePAY\ModelBuilder;
+use RatePAY\Service\DateTime\DateTime;
 use RatePAY\Service\OfflineInstallmentCalculation;
 
 class OfflineInstallmentCalculationTest extends TestCase
 {
-    public function testCallOfflineCalculation()
+    /**
+     * @dataProvider provideOfflineInstalmentCalculations
+     */
+    public function testCallOfflineCalculation($contentData, $currentNow, $expectedAmount)
     {
-        $this->markTestSkipped('Due to lack of understanding of ModelBuilder functionalities!');
-        // it also seems that `callOfflineInstallmentCalculation` is unused at all...
+        DateTime::withTestingNow(new DateTime($currentNow));
+
+        $modelBuilder = new ModelBuilder('Content');
+        $modelBuilder->setArray($contentData);
+
         $service = new OfflineInstallmentCalculation();
-        $calculation = $service->callOfflineCalculation(new ModelBuilder());
-        $this->assertEquals('today', $calculation);
+
+        $instalmentCalculation = $service->callOfflineCalculation($modelBuilder)
+            ->subtype('calculation-by-time');
+
+        DateTime::resetTestingNow();
+
+        $this->assertEquals(round($expectedAmount, 2), $instalmentCalculation);
+    }
+
+    public function provideOfflineInstalmentCalculations()
+    {
+        return [
+            [
+                'contentData' => [
+                    'InstallmentCalculation' => [
+                        'Amount' => 2000,
+                        'CalculationTime' => [
+                            'Month' => 24,
+                        ],
+                        'PaymentFirstday' => 28,
+                        'ServiceCharge' => 3.95,
+                        'InterestRate' => 13.6,
+                    ],
+                ],
+                'currentNow' => '2022-01-23',
+                'expectedAmount' => 95.3, // Payment API = 95.31,
+            ],
+            [
+                'contentData' => [
+                    'InstallmentCalculation' => [
+                        'Amount' => 2000,
+                        'CalculationTime' => [
+                            'Month' => 24,
+                        ],
+                        'PaymentFirstday' => 2,
+                        'ServiceCharge' => 3.95,
+                        'InterestRate' => 10.5,
+                    ],
+                ],
+                'currentNow' => '2022-01-23',
+                'expectedAmount' => 92.7, // Payment API = 92.71,
+            ],
+            [
+                'contentData' => [
+                    'InstallmentCalculation' => [
+                        'Amount' => 1000,
+                        'CalculationTime' => [
+                            'Month' => 24,
+                        ],
+                        'PaymentFirstday' => 2,
+                        'ServiceCharge' => 0,
+                        'InterestRate' => 13.7,
+                    ],
+                ],
+                'currentNow' => '2022-01-24',
+                'expectedAmount' => 47.63, // Payment API = 47.16,
+            ],
+            [
+                'contentData' => [
+                    'InstallmentCalculation' => [
+                        'Amount' => 1000,
+                        'CalculationTime' => [
+                            'Month' => 24,
+                        ],
+                        'PaymentFirstday' => 2,
+                        'ServiceCharge' => 0,
+                        'InterestRate' => 13.7,
+                    ],
+                ],
+                'currentNow' => '2022-01-28',
+                'expectedAmount' => 47.56, // Payment API = 47.1,
+            ],
+        ];
     }
 
     public function testCallZeroPercentOfflineCalculation()
@@ -41,4 +119,54 @@ public function testCallZeroPercentOfflineCalculation()
 
         $this->assertEquals(round(83.33, 2), $monthlyInstalment);
     }
+
+    /**
+     * @dataProvider provideOfflineInstalmentCalculationWithZeroRuntime
+     */
+    public function testCalculationThrowsExceptionsForZeroRuntimes()
+    {
+        $content = new ModelBuilder('Content');
+        $content->setArray([
+            'InstallmentCalculation' => [
+                'Amount' => 2000,
+                'CalculationTime' => ['Month' => 0],
+                'PaymentFirstday' => 2,
+                'ServiceCharge' => 3.95,
+                'InterestRate' => 0,
+            ]
+        ]);
+
+        $this->expectException('RatePAY\Exception\OfflineInstalmentCalculationException');
+
+        $service = new OfflineInstallmentCalculation();
+        $service->callOfflineCalculation($content)->subtype('calculation-by-time');
+    }
+
+    public function provideOfflineInstalmentCalculationWithZeroRuntime()
+    {
+        return [
+            [
+                'contentData' => [
+                    'InstallmentCalculation' => [
+                        'Amount' => 2000,
+                        'CalculationTime' => ['Month' => 0],
+                        'PaymentFirstday' => 2,
+                        'ServiceCharge' => 3.95,
+                        'InterestRate' => 0,
+                    ]
+                ],
+            ],
+            [
+                'contentData' => [
+                    'InstallmentCalculation' => [
+                        'Amount' => 2000,
+                        'CalculationTime' => ['Month' => 0],
+                        'PaymentFirstday' => 2,
+                        'ServiceCharge' => 3.95,
+                        'InterestRate' => 10.7,
+                    ]
+                ],
+            ],
+        ];
+    }
 }