From 8469f4124c26c2aa3912d0041b552506d8a8384e Mon Sep 17 00:00:00 2001
From: Amast <snow@amast.dev>
Date: Thu, 12 Dec 2019 12:58:24 +0800
Subject: [PATCH] Add decimal util.

---
 src/Utils/Decimal.php | 81 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 81 insertions(+)
 create mode 100644 src/Utils/Decimal.php

diff --git a/src/Utils/Decimal.php b/src/Utils/Decimal.php
new file mode 100644
index 0000000..4800f09
--- /dev/null
+++ b/src/Utils/Decimal.php
@@ -0,0 +1,81 @@
+<?php
+
+namespace PdToolKit\Utils;
+
+use Illuminate\Support\Arr;
+
+/**
+ * Class Decimal
+ * @package PdToolKit\Utils
+ * @method Decimal add(int|float|string|Decimal $v);
+ * @method Decimal sub(int|float|string|Decimal $v);
+ * @method Decimal mul(int|float|string|Decimal $v);
+ * @method Decimal div(int|float|string|Decimal $v);
+ */
+class Decimal
+{
+    protected $source;
+    protected $dp = 20;
+    const ROUND_UP = 0;
+    const ROUND_DOWN = 1;
+
+    function __construct($v)
+    {
+        if (!$this->isNumeric($v)) {
+            throw new \Exception("value type must be int|float|string|Decimal.");
+        }
+
+        $this->source = ($v instanceof Decimal) ? $v->getSource() : bcadd($v, 0, $this->dp);
+    }
+
+    private function isNumeric($v)
+    {
+        if ($v instanceof Decimal) return true;
+        return is_numeric($v);
+    }
+
+    function getSource()
+    {
+        return $this->source;
+    }
+
+    function __call($name, $arguments)
+    {
+        $methods = ['add', 'sub', 'mul', 'div'];
+        if (Arr::has($methods, $name)) {
+            $method = "bc$name";
+            $v = new Decimal($arguments[0]);
+            return new Decimal($method($this->source, $v->getSource()));
+        }
+
+        throw new \Exception("method $name not found.");
+    }
+
+    function equals($v): bool
+    {
+        return (new Decimal($v))->getSource() == $this->source;
+    }
+
+    function toFixed(int $dp, int $rm = self::ROUND_UP): string
+    {
+        if ($rm == self::ROUND_UP) {
+            return number_format($this->source, $dp, ".", "");
+        }
+
+        if ($rm == self::ROUND_DOWN) {
+            return bcadd($this->source, 0, $dp);
+        }
+
+        throw new \Exception("$rm must be " . self::ROUND_UP . ' or ' . self::ROUND_DOWN);
+    }
+
+    function toInt(): int
+    {
+        return (int) $this->source;
+    }
+
+    function toFloat(): float
+    {
+        return (float) $this->source;
+    }
+}