From 213d096edc50b489260d99ef8036eab6e2b7d37a Mon Sep 17 00:00:00 2001
From: PostScription <68855126+PostScipton@users.noreply.github.com>
Date: Fri, 30 Apr 2021 14:56:00 +0300
Subject: [PATCH 1/4] Add methods `add()`, `subtract()` and `rebase()`

---
 src/Exceptions/NotNumericException.php        |  24 ++
 src/Exceptions/ValueErrorException.php        |   4 +-
 src/Money.php                                 |  67 ++++-
 src/MoneyInterface.php                        |  35 +++
 src/MoneySettings.php                         |   4 +-
 tests/Feature/ManipulatingMoneyNumberTest.php | 278 ++++++++++++++++++
 6 files changed, 406 insertions(+), 6 deletions(-)
 create mode 100644 src/Exceptions/NotNumericException.php
 create mode 100644 tests/Feature/ManipulatingMoneyNumberTest.php

diff --git a/src/Exceptions/NotNumericException.php b/src/Exceptions/NotNumericException.php
new file mode 100644
index 0000000..50ba797
--- /dev/null
+++ b/src/Exceptions/NotNumericException.php
@@ -0,0 +1,24 @@
+<?php
+
+namespace PostScripton\Money\Exceptions;
+
+class NotNumericException extends ValueErrorException
+{
+    public function __construct(
+        string $method,
+        int $arg_num,
+        string $arg_name = null,
+        $code = 0,
+        BaseException $previous = null
+    ) {
+        parent::__construct(
+            $method,
+            $arg_num,
+            $arg_name,
+            'must be numeric',
+            null,
+            $code,
+            $previous
+        );
+    }
+}
\ No newline at end of file
diff --git a/src/Exceptions/ValueErrorException.php b/src/Exceptions/ValueErrorException.php
index 0d52d20..7028daf 100644
--- a/src/Exceptions/ValueErrorException.php
+++ b/src/Exceptions/ValueErrorException.php
@@ -14,9 +14,9 @@ public function __construct(
         BaseException $previous = null
     ) {
         $error = "ValueError: {$method}(): Argument #{$arg_num} ";
-        $error .= is_null($arg_name) ?: "({$arg_name}) ";
+        $error .= is_null($arg_name) ? '' : "({$arg_name}) ";
         $error .= "{$err_msg}.";
-        $error .= is_null($message) ?: " {$message}.";
+        $error .= is_null($message) ? '' : " {$message}.";
 
         parent::__construct($error, $code, $previous);
     }
diff --git a/src/Money.php b/src/Money.php
index 62d8d2e..4594d75 100644
--- a/src/Money.php
+++ b/src/Money.php
@@ -2,6 +2,8 @@
 
 namespace PostScripton\Money;
 
+use PostScripton\Money\Exceptions\NotNumericException;
+use PostScripton\Money\Exceptions\UndefinedOriginException;
 use PostScripton\Money\Traits\MoneyFormatter;
 use PostScripton\Money\Traits\MoneyStatic;
 
@@ -45,8 +47,8 @@ public function getPureNumber(): float
     public function getNumber(): string
     {
         $amount = $this->settings->getOrigin() === MoneySettings::ORIGIN_INT
-            ? (float)($this->number / $this->getDivisor())
-            : $this->number;
+            ? (float)($this->getPureNumber() / $this->getDivisor())
+            : $this->getPureNumber();
 
         $money = number_format(
             $amount,
@@ -67,6 +69,67 @@ public function getNumber(): string
         return $money;
     }
 
+    public function add($number, int $origin = MoneySettings::ORIGIN_INT): Money
+    {
+        // Error handlers
+        if (!is_numeric($number)) {
+            throw new NotNumericException(__METHOD__, 1, '$number');
+        }
+        if (!in_array($origin, MoneySettings::ORIGINS)) {
+            throw new UndefinedOriginException(__METHOD__, 2, '$origin');
+        }
+
+        $this->number += $this->numberIntoCorrectOrigin($number, $origin);
+        return $this;
+    }
+
+    public function subtract($number, int $origin = MoneySettings::ORIGIN_INT): Money
+    {
+        // Error handlers
+        if (!is_numeric($number)) {
+            throw new NotNumericException(__METHOD__, 1, '$number');
+        }
+        if (!in_array($origin, MoneySettings::ORIGINS)) {
+            throw new UndefinedOriginException(__METHOD__, 2, '$origin');
+        }
+
+        $number = $this->numberIntoCorrectOrigin($number, $origin);
+
+        // If less than 0, then result must be 0
+        if ($this->getPureNumber() - $number < 0) {
+            $number = $this->getPureNumber();
+        }
+
+        $this->number -= $number;
+        return $this;
+    }
+
+    public function rebase($number, int $origin = MoneySettings::ORIGIN_INT): Money
+    {
+        // Error handlers
+        if (!is_numeric($number)) {
+            throw new NotNumericException(__METHOD__, 1, '$number');
+        }
+        if (!in_array($origin, MoneySettings::ORIGINS)) {
+            throw new UndefinedOriginException(__METHOD__, 2, '$origin');
+        }
+
+        $this->number = $this->numberIntoCorrectOrigin($number, $origin);
+        return $this;
+    }
+
+    private function numberIntoCorrectOrigin($number, int $origin = MoneySettings::ORIGIN_INT)
+    {
+        // If origins are not the same
+        if ($this->settings->getOrigin() !== $origin) {
+            return $this->settings->getOrigin() === MoneySettings::ORIGIN_INT
+                ? floor($number * $this->getDivisor()) // $origin is float
+                : $number / $this->getDivisor(); // $origin is int
+        }
+
+        return $number;
+    }
+
     public function convertOfflineInto(Currency $currency, float $coeff): Money
     {
         $new_amount = $this->getPureNumber() * $coeff;
diff --git a/src/MoneyInterface.php b/src/MoneyInterface.php
index 4f41842..ce75c16 100644
--- a/src/MoneyInterface.php
+++ b/src/MoneyInterface.php
@@ -118,6 +118,41 @@ public function getNumber(): string;
      */
     public function getPureNumber(): float;
 
+    /**
+     * Adds a number to the money. It's like <p>
+     * `$100 + $50 = $150` </p>
+     * @param $number <p>
+     * A number that will be added </p>
+     * @param int $origin <p>
+     * Origin of the number whether it is integer of float. </p> <p>
+     * Use `Money::ORIGIN_*` to ensure it's correct </p>
+     * @return Money
+     */
+    public function add($number, int $origin = MoneySettings::ORIGIN_INT): Money;
+
+    /**
+     * Subtracts a number from the money. It's like <p>
+     * `$150 - $50 = $100` </p>
+     * @param $number <p>
+     * A number that will be subtracted </p>
+     * @param int $origin <p>
+     * Origin of the number whether it is integer of float. </p> <p>
+     * Use `Money::ORIGIN_*` to ensure it's correct </p>
+     * @return Money
+     */
+    public function subtract($number, int $origin = MoneySettings::ORIGIN_INT): Money;
+
+    /**
+     * Rebases the money on a number
+     * @param $number <p>
+     * A number to which the money will be rebased </p>
+     * @param int $origin <p>
+     * Origin of the number whether it is integer of float. </p> <p>
+     * Use `Money::ORIGIN_*` to ensure it's correct </p>
+     * @return Money
+     */
+    public function rebase($number, int $origin = MoneySettings::ORIGIN_INT): Money;
+
     /**
      * Converts money into another currency using coefficient between currencies
      * <p>USD -> RUB = 75.79 / 1</p>
diff --git a/src/MoneySettings.php b/src/MoneySettings.php
index 808110f..12a6eec 100644
--- a/src/MoneySettings.php
+++ b/src/MoneySettings.php
@@ -10,7 +10,7 @@ class MoneySettings implements MoneySettingsInterface
 {
     public const ORIGIN_INT = 0;
     public const ORIGIN_FLOAT = 1;
-    private const ORIGIN = [
+    public const ORIGINS = [
         self::ORIGIN_INT,
         self::ORIGIN_FLOAT,
     ];
@@ -89,7 +89,7 @@ public function setCurrency(Currency $currency): MoneySettings
 
     public function setOrigin(int $origin): MoneySettings
     {
-        if (!in_array($origin, self::ORIGIN)) {
+        if (!in_array($origin, self::ORIGINS)) {
             throw new UndefinedOriginException(__METHOD__, 1, '$origin');
         }
 
diff --git a/tests/Feature/ManipulatingMoneyNumberTest.php b/tests/Feature/ManipulatingMoneyNumberTest.php
new file mode 100644
index 0000000..3cbd2a8
--- /dev/null
+++ b/tests/Feature/ManipulatingMoneyNumberTest.php
@@ -0,0 +1,278 @@
+<?php
+
+namespace PostScripton\Money\Tests;
+
+use PostScripton\Money\Money;
+use PostScripton\Money\MoneySettings;
+use PostScripton\Money\Exceptions\UndefinedOriginException;
+use PostScripton\Money\Exceptions\NotNumericException;
+
+class ManipulatingMoneyNumberTest extends TestCase
+{
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function IntAddInt()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(1000, $settings);
+
+        $this->assertEquals('$ 150', $money->add(500));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function IntAddFloat()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(1000, $settings);
+
+        $this->assertEquals('$ 150', $money->add(50, MoneySettings::ORIGIN_FLOAT));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function FloatAddFloat()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_FLOAT);
+        $money = new Money(100, $settings);
+
+        $this->assertEquals('$ 150', $money->add(50, MoneySettings::ORIGIN_FLOAT));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function FloatAddInt()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_FLOAT);
+        $money = new Money(100, $settings);
+
+        $this->assertEquals('$ 150', $money->add(500));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     */
+    public function AddNumericError()
+    {
+        $this->expectException(NotNumericException::class);
+
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(100, $settings);
+
+        $money->add('asdf');
+    }
+
+    /** @test
+     * @throws NotNumericException
+     */
+    public function AddOriginError()
+    {
+        $this->expectException(UndefinedOriginException::class);
+
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(100, $settings);
+
+        $money->add(500, 1234);
+    }
+
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function IntSubtractInt()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(1500, $settings);
+
+        $this->assertEquals('$ 100', $money->subtract(500));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function IntSubtractFloat()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(1500, $settings);
+
+        $this->assertEquals('$ 100', $money->subtract(50, MoneySettings::ORIGIN_FLOAT));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function FloatSubtractFloat()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_FLOAT);
+        $money = new Money(150, $settings);
+
+        $this->assertEquals('$ 100', $money->subtract(50, MoneySettings::ORIGIN_FLOAT));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function FloatSubtractInt()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_FLOAT);
+        $money = new Money(150, $settings);
+
+        $this->assertEquals('$ 100', $money->subtract(500));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     */
+    public function SubtractNumericError()
+    {
+        $this->expectException(NotNumericException::class);
+
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(100, $settings);
+
+        $money->subtract('asdf');
+    }
+
+    /** @test
+     * @throws NotNumericException
+     */
+    public function SubtractOriginError()
+    {
+        $this->expectException(UndefinedOriginException::class);
+
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(100, $settings);
+
+        $money->subtract(500, 1234);
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function IntSubtractInt_MoreThanMoneyHas()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(500, $settings);
+
+        $this->assertEquals('$ 0', $money->subtract(1000));
+        $this->assertEquals(0, $money->getPureNumber());
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function IntSubtractFloat_MoreThanMoneyHas()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(500, $settings);
+
+        $this->assertEquals('$ 0', $money->subtract(100, MoneySettings::ORIGIN_FLOAT));
+        $this->assertEquals(0, $money->getPureNumber());
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function FloatSubtractFloat_MoreThanMoneyHas()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_FLOAT);
+        $money = new Money(50, $settings);
+
+        $this->assertEquals('$ 0', $money->subtract(100, MoneySettings::ORIGIN_FLOAT));
+        $this->assertEquals(0, $money->getPureNumber());
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function FloatSubtractInt_MoreThanMoneyHas()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_FLOAT);
+        $money = new Money(50, $settings);
+
+        $this->assertEquals('$ 0', $money->subtract(1000));
+        $this->assertEquals(0, $money->getPureNumber());
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function RebaseInt()
+    {
+        $money = new Money(1500);
+
+        $this->assertEquals('$ 100', $money->rebase(1000));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function RebaseFloat()
+    {
+        $money = new Money(1500);
+
+        $this->assertEquals('$ 100', $money->rebase(100, MoneySettings::ORIGIN_FLOAT));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     */
+    public function RebaseNumericError()
+    {
+        $this->expectException(NotNumericException::class);
+
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(100, $settings);
+
+        $money->rebase('asdf');
+    }
+
+    /** @test
+     * @throws NotNumericException
+     */
+    public function RebaseOriginError()
+    {
+        $this->expectException(UndefinedOriginException::class);
+
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(100, $settings);
+
+        $money->rebase(500, 1234);
+    }
+}
\ No newline at end of file

From beac9a0675a96eebc1266498f9ad4e69e09a872e Mon Sep 17 00:00:00 2001
From: PostScription <68855126+PostScipton@users.noreply.github.com>
Date: Fri, 30 Apr 2021 14:56:00 +0300
Subject: [PATCH 2/4] Add methods add(), subtract() and rebase()

---
 src/Exceptions/NotNumericException.php        |  24 ++
 src/Exceptions/ValueErrorException.php        |   4 +-
 src/Money.php                                 |  67 ++++-
 src/MoneyInterface.php                        |  35 +++
 src/MoneySettings.php                         |   4 +-
 tests/Feature/ManipulatingMoneyNumberTest.php | 278 ++++++++++++++++++
 6 files changed, 406 insertions(+), 6 deletions(-)
 create mode 100644 src/Exceptions/NotNumericException.php
 create mode 100644 tests/Feature/ManipulatingMoneyNumberTest.php

diff --git a/src/Exceptions/NotNumericException.php b/src/Exceptions/NotNumericException.php
new file mode 100644
index 0000000..50ba797
--- /dev/null
+++ b/src/Exceptions/NotNumericException.php
@@ -0,0 +1,24 @@
+<?php
+
+namespace PostScripton\Money\Exceptions;
+
+class NotNumericException extends ValueErrorException
+{
+    public function __construct(
+        string $method,
+        int $arg_num,
+        string $arg_name = null,
+        $code = 0,
+        BaseException $previous = null
+    ) {
+        parent::__construct(
+            $method,
+            $arg_num,
+            $arg_name,
+            'must be numeric',
+            null,
+            $code,
+            $previous
+        );
+    }
+}
\ No newline at end of file
diff --git a/src/Exceptions/ValueErrorException.php b/src/Exceptions/ValueErrorException.php
index 0d52d20..7028daf 100644
--- a/src/Exceptions/ValueErrorException.php
+++ b/src/Exceptions/ValueErrorException.php
@@ -14,9 +14,9 @@ public function __construct(
         BaseException $previous = null
     ) {
         $error = "ValueError: {$method}(): Argument #{$arg_num} ";
-        $error .= is_null($arg_name) ?: "({$arg_name}) ";
+        $error .= is_null($arg_name) ? '' : "({$arg_name}) ";
         $error .= "{$err_msg}.";
-        $error .= is_null($message) ?: " {$message}.";
+        $error .= is_null($message) ? '' : " {$message}.";
 
         parent::__construct($error, $code, $previous);
     }
diff --git a/src/Money.php b/src/Money.php
index 62d8d2e..4594d75 100644
--- a/src/Money.php
+++ b/src/Money.php
@@ -2,6 +2,8 @@
 
 namespace PostScripton\Money;
 
+use PostScripton\Money\Exceptions\NotNumericException;
+use PostScripton\Money\Exceptions\UndefinedOriginException;
 use PostScripton\Money\Traits\MoneyFormatter;
 use PostScripton\Money\Traits\MoneyStatic;
 
@@ -45,8 +47,8 @@ public function getPureNumber(): float
     public function getNumber(): string
     {
         $amount = $this->settings->getOrigin() === MoneySettings::ORIGIN_INT
-            ? (float)($this->number / $this->getDivisor())
-            : $this->number;
+            ? (float)($this->getPureNumber() / $this->getDivisor())
+            : $this->getPureNumber();
 
         $money = number_format(
             $amount,
@@ -67,6 +69,67 @@ public function getNumber(): string
         return $money;
     }
 
+    public function add($number, int $origin = MoneySettings::ORIGIN_INT): Money
+    {
+        // Error handlers
+        if (!is_numeric($number)) {
+            throw new NotNumericException(__METHOD__, 1, '$number');
+        }
+        if (!in_array($origin, MoneySettings::ORIGINS)) {
+            throw new UndefinedOriginException(__METHOD__, 2, '$origin');
+        }
+
+        $this->number += $this->numberIntoCorrectOrigin($number, $origin);
+        return $this;
+    }
+
+    public function subtract($number, int $origin = MoneySettings::ORIGIN_INT): Money
+    {
+        // Error handlers
+        if (!is_numeric($number)) {
+            throw new NotNumericException(__METHOD__, 1, '$number');
+        }
+        if (!in_array($origin, MoneySettings::ORIGINS)) {
+            throw new UndefinedOriginException(__METHOD__, 2, '$origin');
+        }
+
+        $number = $this->numberIntoCorrectOrigin($number, $origin);
+
+        // If less than 0, then result must be 0
+        if ($this->getPureNumber() - $number < 0) {
+            $number = $this->getPureNumber();
+        }
+
+        $this->number -= $number;
+        return $this;
+    }
+
+    public function rebase($number, int $origin = MoneySettings::ORIGIN_INT): Money
+    {
+        // Error handlers
+        if (!is_numeric($number)) {
+            throw new NotNumericException(__METHOD__, 1, '$number');
+        }
+        if (!in_array($origin, MoneySettings::ORIGINS)) {
+            throw new UndefinedOriginException(__METHOD__, 2, '$origin');
+        }
+
+        $this->number = $this->numberIntoCorrectOrigin($number, $origin);
+        return $this;
+    }
+
+    private function numberIntoCorrectOrigin($number, int $origin = MoneySettings::ORIGIN_INT)
+    {
+        // If origins are not the same
+        if ($this->settings->getOrigin() !== $origin) {
+            return $this->settings->getOrigin() === MoneySettings::ORIGIN_INT
+                ? floor($number * $this->getDivisor()) // $origin is float
+                : $number / $this->getDivisor(); // $origin is int
+        }
+
+        return $number;
+    }
+
     public function convertOfflineInto(Currency $currency, float $coeff): Money
     {
         $new_amount = $this->getPureNumber() * $coeff;
diff --git a/src/MoneyInterface.php b/src/MoneyInterface.php
index 4f41842..ce75c16 100644
--- a/src/MoneyInterface.php
+++ b/src/MoneyInterface.php
@@ -118,6 +118,41 @@ public function getNumber(): string;
      */
     public function getPureNumber(): float;
 
+    /**
+     * Adds a number to the money. It's like <p>
+     * `$100 + $50 = $150` </p>
+     * @param $number <p>
+     * A number that will be added </p>
+     * @param int $origin <p>
+     * Origin of the number whether it is integer of float. </p> <p>
+     * Use `Money::ORIGIN_*` to ensure it's correct </p>
+     * @return Money
+     */
+    public function add($number, int $origin = MoneySettings::ORIGIN_INT): Money;
+
+    /**
+     * Subtracts a number from the money. It's like <p>
+     * `$150 - $50 = $100` </p>
+     * @param $number <p>
+     * A number that will be subtracted </p>
+     * @param int $origin <p>
+     * Origin of the number whether it is integer of float. </p> <p>
+     * Use `Money::ORIGIN_*` to ensure it's correct </p>
+     * @return Money
+     */
+    public function subtract($number, int $origin = MoneySettings::ORIGIN_INT): Money;
+
+    /**
+     * Rebases the money on a number
+     * @param $number <p>
+     * A number to which the money will be rebased </p>
+     * @param int $origin <p>
+     * Origin of the number whether it is integer of float. </p> <p>
+     * Use `Money::ORIGIN_*` to ensure it's correct </p>
+     * @return Money
+     */
+    public function rebase($number, int $origin = MoneySettings::ORIGIN_INT): Money;
+
     /**
      * Converts money into another currency using coefficient between currencies
      * <p>USD -> RUB = 75.79 / 1</p>
diff --git a/src/MoneySettings.php b/src/MoneySettings.php
index 808110f..12a6eec 100644
--- a/src/MoneySettings.php
+++ b/src/MoneySettings.php
@@ -10,7 +10,7 @@ class MoneySettings implements MoneySettingsInterface
 {
     public const ORIGIN_INT = 0;
     public const ORIGIN_FLOAT = 1;
-    private const ORIGIN = [
+    public const ORIGINS = [
         self::ORIGIN_INT,
         self::ORIGIN_FLOAT,
     ];
@@ -89,7 +89,7 @@ public function setCurrency(Currency $currency): MoneySettings
 
     public function setOrigin(int $origin): MoneySettings
     {
-        if (!in_array($origin, self::ORIGIN)) {
+        if (!in_array($origin, self::ORIGINS)) {
             throw new UndefinedOriginException(__METHOD__, 1, '$origin');
         }
 
diff --git a/tests/Feature/ManipulatingMoneyNumberTest.php b/tests/Feature/ManipulatingMoneyNumberTest.php
new file mode 100644
index 0000000..3cbd2a8
--- /dev/null
+++ b/tests/Feature/ManipulatingMoneyNumberTest.php
@@ -0,0 +1,278 @@
+<?php
+
+namespace PostScripton\Money\Tests;
+
+use PostScripton\Money\Money;
+use PostScripton\Money\MoneySettings;
+use PostScripton\Money\Exceptions\UndefinedOriginException;
+use PostScripton\Money\Exceptions\NotNumericException;
+
+class ManipulatingMoneyNumberTest extends TestCase
+{
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function IntAddInt()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(1000, $settings);
+
+        $this->assertEquals('$ 150', $money->add(500));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function IntAddFloat()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(1000, $settings);
+
+        $this->assertEquals('$ 150', $money->add(50, MoneySettings::ORIGIN_FLOAT));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function FloatAddFloat()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_FLOAT);
+        $money = new Money(100, $settings);
+
+        $this->assertEquals('$ 150', $money->add(50, MoneySettings::ORIGIN_FLOAT));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function FloatAddInt()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_FLOAT);
+        $money = new Money(100, $settings);
+
+        $this->assertEquals('$ 150', $money->add(500));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     */
+    public function AddNumericError()
+    {
+        $this->expectException(NotNumericException::class);
+
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(100, $settings);
+
+        $money->add('asdf');
+    }
+
+    /** @test
+     * @throws NotNumericException
+     */
+    public function AddOriginError()
+    {
+        $this->expectException(UndefinedOriginException::class);
+
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(100, $settings);
+
+        $money->add(500, 1234);
+    }
+
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function IntSubtractInt()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(1500, $settings);
+
+        $this->assertEquals('$ 100', $money->subtract(500));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function IntSubtractFloat()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(1500, $settings);
+
+        $this->assertEquals('$ 100', $money->subtract(50, MoneySettings::ORIGIN_FLOAT));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function FloatSubtractFloat()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_FLOAT);
+        $money = new Money(150, $settings);
+
+        $this->assertEquals('$ 100', $money->subtract(50, MoneySettings::ORIGIN_FLOAT));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function FloatSubtractInt()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_FLOAT);
+        $money = new Money(150, $settings);
+
+        $this->assertEquals('$ 100', $money->subtract(500));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     */
+    public function SubtractNumericError()
+    {
+        $this->expectException(NotNumericException::class);
+
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(100, $settings);
+
+        $money->subtract('asdf');
+    }
+
+    /** @test
+     * @throws NotNumericException
+     */
+    public function SubtractOriginError()
+    {
+        $this->expectException(UndefinedOriginException::class);
+
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(100, $settings);
+
+        $money->subtract(500, 1234);
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function IntSubtractInt_MoreThanMoneyHas()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(500, $settings);
+
+        $this->assertEquals('$ 0', $money->subtract(1000));
+        $this->assertEquals(0, $money->getPureNumber());
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function IntSubtractFloat_MoreThanMoneyHas()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(500, $settings);
+
+        $this->assertEquals('$ 0', $money->subtract(100, MoneySettings::ORIGIN_FLOAT));
+        $this->assertEquals(0, $money->getPureNumber());
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function FloatSubtractFloat_MoreThanMoneyHas()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_FLOAT);
+        $money = new Money(50, $settings);
+
+        $this->assertEquals('$ 0', $money->subtract(100, MoneySettings::ORIGIN_FLOAT));
+        $this->assertEquals(0, $money->getPureNumber());
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function FloatSubtractInt_MoreThanMoneyHas()
+    {
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_FLOAT);
+        $money = new Money(50, $settings);
+
+        $this->assertEquals('$ 0', $money->subtract(1000));
+        $this->assertEquals(0, $money->getPureNumber());
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function RebaseInt()
+    {
+        $money = new Money(1500);
+
+        $this->assertEquals('$ 100', $money->rebase(1000));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     * @throws NotNumericException
+     */
+    public function RebaseFloat()
+    {
+        $money = new Money(1500);
+
+        $this->assertEquals('$ 100', $money->rebase(100, MoneySettings::ORIGIN_FLOAT));
+    }
+
+    /** @test
+     * @throws UndefinedOriginException
+     */
+    public function RebaseNumericError()
+    {
+        $this->expectException(NotNumericException::class);
+
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(100, $settings);
+
+        $money->rebase('asdf');
+    }
+
+    /** @test
+     * @throws NotNumericException
+     */
+    public function RebaseOriginError()
+    {
+        $this->expectException(UndefinedOriginException::class);
+
+        $settings = (new MoneySettings())
+            ->setOrigin(MoneySettings::ORIGIN_INT);
+        $money = new Money(100, $settings);
+
+        $money->rebase(500, 1234);
+    }
+}
\ No newline at end of file

From 5b1890cf14847959486b993edd29a6ed15b09f23 Mon Sep 17 00:00:00 2001
From: PostScription <68855126+PostScipton@users.noreply.github.com>
Date: Fri, 30 Apr 2021 16:28:08 +0300
Subject: [PATCH 3/4] Update README.md

---
 README.md | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 65 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 7be637e..79b9176 100644
--- a/README.md
+++ b/README.md
@@ -433,7 +433,71 @@ $money->getPureNumber(); // 132.76686139139672
 
 ---
 
+##### `add()`
+
+adds a number to the money
+
+```php
+use PostScripton\Money\Money;
+
+$money = new Money(1000);   // "$ 100"
+$money->add(500);           // "$ 150"
+```
+
+```php
+use PostScripton\Money\Money;
+use PostScripton\Money\MoneySettings;
+
+$money = new Money(1000);                       // "$ 100"
+$money->add(50.0, MoneySettings::ORIGIN_FLOAT); // "$ 150"
+```
+
+---
+
+##### `subtract()`
+
+subtracts a number from the money
+
+```php
+use PostScripton\Money\Money;
+
+$money = new Money(1500);   // "$ 150"
+$money->subtract(500);      // "$ 100"
+```
+
+```php
+use PostScripton\Money\Money;
+use PostScripton\Money\MoneySettings;
+
+$money = new Money(1500);                               // "$ 150"
+$money->subtract(50.0, MoneySettings::ORIGIN_FLOAT);    // "$ 100"
+```
+
+---
+
+##### `rebase()`
+
+a number to which the money will be rebased
+
+```php
+use PostScripton\Money\Money;
+
+$money = new Money(1500);   // "$ 150"
+$money->rebase(100);        // "$ 10"
+```
+
+```php
+use PostScripton\Money\Money;
+use PostScripton\Money\MoneySettings;
+
+$money = new Money(1500);                           // "$ 150"
+$money->rebase(10.0, MoneySettings::ORIGIN_FLOAT);  // "$ 10"
+```
+
+---
+
 ##### `convertOfflineInto()`
+
 converts Money object into the chosen currency
 
 ```php
@@ -477,4 +541,4 @@ use PostScripton\Money\Money;
 
 $money = new Money(1234);
 $money->toString(); // "$ 123.4"
-```
+```
\ No newline at end of file

From 10a78c8a6efc03114085c2a67b91774945d9ea67 Mon Sep 17 00:00:00 2001
From: Sergey <68855126+PostScripton@users.noreply.github.com>
Date: Fri, 30 Apr 2021 16:34:01 +0300
Subject: [PATCH 4/4] v2.1.0

---
 composer.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/composer.json b/composer.json
index f50abb3..9fbc1a2 100644
--- a/composer.json
+++ b/composer.json
@@ -1,7 +1,7 @@
 {
     "name": "postscripton/laravel-money",
     "description": "A convenient way to convert numbers from DB or inputs into money strings for humans",
-  	"version": "2.0.0",
+  	"version": "2.1.0",
   	"type": "library",
     "license": "MIT",
     "authors": [