Mass refactoring

Some changes:
+ Added support of functions with multiple arguments
+ Added some default function (min, max, avg). just example of multiple arguments :)
- Removed variables support (I think they pointless)
~ All tokens now in individual classes
~ Parsing based on regular expressions
~ Fix negative numbers
~ Fix grouping with brackets

1 files changed, 46 insertions, 0 deletions

diff --git a/src/NXP/Classes/Calculator.php b/src/NXP/Classes/Calculator.php
new file mode 100644
index 0000000..e74b7ab
--- /dev/null
+++ b/src/NXP/Classes/Calculator.php
@@ -0,0 +1,46 @@
+<?php
+/**
+ * This file is part of the MathExecutor package
+ *
+ * (c) Alexander Kiryukhin
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code
+ */
+
+namespace NXP\Classes;
+
+use NXP\Classes\Token\InterfaceOperator;
+use NXP\Classes\Token\TokenFunction;
+use NXP\Classes\Token\TokenNumber;
+use NXP\Exception\IncorrectExpressionException;
+
+/**
+ * @author Alexander Kiryukhin <alexander@symdev.org>
+ */
+class Calculator
+{
+    /**
+     * @param  array                                       $tokens Tokens in reverse polish notation
+     * @return number
+     * @throws \NXP\Exception\IncorrectExpressionException
+     */
+    public function calculate($tokens)
+    {
+        $stack = array();
+        foreach ($tokens as $token) {
+            if ($token instanceof TokenNumber) {
+                array_push($stack, $token);
+            }
+            if ($token instanceof InterfaceOperator || $token instanceof TokenFunction) {
+                array_push($stack, $token->execute($stack));
+            }
+        }
+        $result = array_pop($stack);
+        if (!empty($stack)) {
+            throw new IncorrectExpressionException();
+        }
+
+        return $result->getValue();
+    }
+}