commit existing workshops

workshop5/Models/Calculator.php

@@ -0,0 +1,50 @@
+<?php
+class Calculator
+{
+    /*
+     * Class for calculating 2 numbers
+     */
+    var $expression;
+
+    /*
+     * Constructor takes 2 numbers and an operator
+     * @param int $number Number to be converted
+     * @param string $unit Conversion unit
+     */
+    public function __construct($expression = '')
+    {
+        $this->expression = $expression;
+    }
+
+    /*
+     * Calculates number and returns result
+     * @return string Result of calculation
+     */
+    public function calculate(): string
+    {
+        $result = false;
+        $this->expression = preg_replace('/\s+/', '', $this->expression);
+        if(preg_match('/(\d+)([x\*\-\+\/])(\d+)/', $this->expression, $matches)) {
+            $number1 = $matches[1];
+            $operator = $matches[2];
+            $number2 = $matches[3];
+            if (is_numeric($number1) && is_numeric($number2)) {
+                switch ($operator) {
+                    case '+':
+                        $result = ($number1 + $number2);
+                        break;
+                    case '-':
+                        $result = ($number1 - $number2);
+                        break;
+                    case '*':
+                    case 'x':
+                        $result = ($number1 * $number2);
+                        break;
+                    case '/':
+                        $result = ($number1 / $number2);
+                        break;
+                }
+            }
+        } return $result;
+    }
+}