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, 35 insertions, 316 deletions

diff --git a/src/NXP/MathExecutor.php b/src/NXP/MathExecutor.php
index 482b4b7..a93a305 100644
--- a/src/NXP/MathExecutor.php
+++ b/src/NXP/MathExecutor.php
@@ -11,14 +11,10 @@
 
 namespace NXP;
 
-use NXP\Classes\Func;
-use NXP\Classes\Operand;
+use NXP\Classes\Calculator;
+use NXP\Classes\Lexer;
 use NXP\Classes\Token;
-use NXP\Classes\TokenParser;
-use NXP\Exception\IncorrectExpressionException;
-use NXP\Exception\UnknownFunctionException;
-use NXP\Exception\UnknownOperatorException;
-use NXP\Exception\UnknownTokenException;
+use NXP\Classes\TokenFactory;
 
 /**
  * Class MathExecutor
@@ -27,35 +23,9 @@ use NXP\Exception\UnknownTokenException;
 class MathExecutor
 {
     /**
-     * Available operators
-     *
-     * @var array
+     * @var TokenFactory
      */
-    private $operators = array();
-
-    /**
-     * Available functions
-     *
-     * @var array
-     */
-    private $functions = array();
-
-    /**
-     * Available variables
-     *
-     * @var array
-     */
-    private $variables = array();
-
-    /**
-     * @var \SplStack
-     */
-    private $stack;
-
-    /**
-     * @var \SplQueue
-     */
-    private $queue;
+    private $tokenFactory;
 
     /**
      * Base math operators
@@ -67,10 +37,6 @@ class MathExecutor
 
     public function __clone()
     {
-        $this->variables = array();
-        $this->operators = array();
-        $this->functions = array();
-
         $this->addDefaults();
     }
 
@@ -79,29 +45,35 @@ class MathExecutor
      */
     protected function addDefaults()
     {
-        $this->addOperator(new Operand('+', 1, Operand::LEFT_ASSOCIATED, Operand::BINARY, function ($op1, $op2) { return $op1+$op2; }));
-        $this->addOperator(new Operand('-', 1, Operand::LEFT_ASSOCIATED, Operand::BINARY, function ($op1, $op2) { return $op1-$op2; }));
-        $this->addOperator(new Operand('*', 2, Operand::LEFT_ASSOCIATED, Operand::BINARY, function ($op1, $op2) { return $op1*$op2; }));
-        $this->addOperator(new Operand('/', 2, Operand::LEFT_ASSOCIATED, Operand::BINARY, function ($op1, $op2) { return $op1/$op2; }));
-        $this->addOperator(new Operand('^', 3, Operand::LEFT_ASSOCIATED, Operand::BINARY, function ($op1, $op2) { return pow($op1,$op2); }));
+        $this->tokenFactory = new TokenFactory();
+
+        $this->tokenFactory->addOperator('NXP\Classes\Token\TokenPlus');
+        $this->tokenFactory->addOperator('NXP\Classes\Token\TokenMinus');
+        $this->tokenFactory->addOperator('NXP\Classes\Token\TokenMultiply');
+        $this->tokenFactory->addOperator('NXP\Classes\Token\TokenDivision');
+        $this->tokenFactory->addOperator('NXP\Classes\Token\TokenDegree');
+
+        $this->tokenFactory->addFunction('sin', 'sin');
+        $this->tokenFactory->addFunction('cos', 'cos');
+        $this->tokenFactory->addFunction('tn', 'tan');
+        $this->tokenFactory->addFunction('asin', 'asin');
+        $this->tokenFactory->addFunction('acos', 'acos');
+        $this->tokenFactory->addFunction('atn', 'atan');
+        $this->tokenFactory->addFunction('min', 'min', 2);
+        $this->tokenFactory->addFunction('max', 'max', 2);
+        $this->tokenFactory->addFunction('avg', function($arg1, $arg2) { return ($arg1 + $arg2) / 2; }, 2);
 
-        $this->addFunction(new Func('sin',  function ($arg) { return sin($arg); }));
-        $this->addFunction(new Func('cos',  function ($arg) { return cos($arg); }));
-        $this->addFunction(new Func('tn',   function ($arg) { return tan($arg); }));
-        $this->addFunction(new Func('asin', function ($arg) { return asin($arg); }));
-        $this->addFunction(new Func('acos', function ($arg) { return acos($arg); }));
-        $this->addFunction(new Func('atn',  function ($arg) { return atan($arg); }));
     }
 
     /**
      * Add operator to executor
      *
-     * @param  Operand      $operator
+     * @param  string       $operatorClass Class of operator token
      * @return MathExecutor
      */
-    public function addOperator(Operand $operator)
+    public function addOperator($operatorClass)
     {
-        $this->operators[$operator->getSymbol()] = $operator;
+        $this->tokenFactory->addOperator($operatorClass);
 
         return $this;
     }
@@ -109,79 +81,14 @@ class MathExecutor
     /**
      * Add function to executor
      *
-     * @param  string       $name
-     * @param  callable     $function
+     * @param string   $name     Name of function
+     * @param callable $function Function
+     * @param int      $places   Count of arguments
      * @return MathExecutor
      */
-    public function addFunction($name, callable $function = null)
+    public function addFunction($name, callable $function = null, $places = 1)
     {
-        if ($name instanceof Func) {
-            $this->functions[$name->getName()] = $name->getCallback();
-        } else {
-            $this->functions[$name] = $function;
-        }
-
-        return $this;
-    }
-
-    /**
-     * Add variable to executor
-     *
-     * @param  string        $variable
-     * @param  integer|float $value
-     * @throws \Exception
-     * @return MathExecutor
-     */
-    public function setVar($variable, $value)
-    {
-        if (!is_numeric($value)) {
-            throw new \Exception("Variable value must be a number");
-        }
-
-        $this->variables[$variable] = $value;
-
-        return $this;
-    }
-
-    /**
-     * Add variables to executor
-     *
-     * @param  array        $variables
-     * @param  bool         $clear     Clear previous variables
-     * @return MathExecutor
-     */
-    public function setVars(array $variables, $clear = true)
-    {
-        if ($clear) {
-            $this->removeVars();
-        }
-
-        foreach ($variables as $name => $value) {
-            $this->setVar($name, $value);
-        }
-
-        return $this;
-    }
-
-    /**
-     * Remove variable from executor
-     *
-     * @param  string       $variable
-     * @return MathExecutor
-     */
-    public function removeVar($variable)
-    {
-        unset ($this->variables[$variable]);
-
-        return $this;
-    }
-
-    /**
-     * Remove all variables
-     */
-    public function removeVars()
-    {
-        $this->variables = array();
+        $this->tokenFactory->addFunction($name, $function, $places);
 
         return $this;
     }
@@ -194,199 +101,11 @@ class MathExecutor
      */
     public function execute($expression)
     {
-        $reversePolishNotation = $this->convertToReversePolishNotation($expression);
-        $result = $this->calculateReversePolishNotation($reversePolishNotation);
-
-        return $result;
-    }
-
-    /**
-     * Convert expression from normal expression form to RPN
-     *
-     * @param $expression
-     * @return \SplQueue
-     * @throws \Exception
-     */
-    private function convertToReversePolishNotation($expression)
-    {
-        $this->stack = new \SplStack();
-        $this->queue = new \SplQueue();
-
-        $tokenParser = new TokenParser();
-        $input = $tokenParser->tokenize($expression);
-
-        foreach ($input as $token) {
-            $this->categorizeToken($token);
-        }
-
-        while (!$this->stack->isEmpty()) {
-            $token = $this->stack->pop();
-
-            if ($token->getType() != Token::OPERATOR) {
-                throw new \Exception('Opening bracket without closing bracket');
-            }
-
-            $this->queue->push($token);
-        }
-
-        return $this->queue;
-    }
-
-    /**
-     * @param  Token      $token
-     * @throws \Exception
-     */
-    private function categorizeToken(Token $token)
-    {
-        switch ($token->getType()) {
-            case Token::NUMBER :
-                $this->queue->push($token);
-                break;
-
-            case Token::STRING:
-                if (array_key_exists($token->getValue(), $this->variables)) {
-                    $this->queue->push(new Token(Token::NUMBER, $this->variables[$token->getValue()]));
-                } else {
-                    $this->stack->push($token);
-                }
-                break;
-
-            case Token::LEFT_BRACKET:
-                $this->stack->push($token);
-                break;
-
-            case Token::RIGHT_BRACKET:
-                $previousToken = $this->stack->pop();
-                while (!$this->stack->isEmpty() && ($previousToken->getType() != Token::LEFT_BRACKET)) {
-                    $this->queue->push($previousToken);
-                    $previousToken = $this->stack->pop();
-                }
-                if ((!$this->stack->isEmpty()) && ($this->stack->top()->getType() == Token::STRING)) {
-                    $funcName = $this->stack->pop()->getValue();
-                    if (!array_key_exists($funcName, $this->functions)) {
-                        throw new UnknownFunctionException(sprintf(
-                            'Unknown function: "%s".',
-                            $funcName
-                        ));
-                    }
-                    $this->queue->push(new Token(Token::FUNC, $funcName));
-                }
-                break;
-
-            case Token::OPERATOR:
-                if (!array_key_exists($token->getValue(), $this->operators)) {
-                    throw new UnknownOperatorException(sprintf(
-                        'Unknown operator: "%s".',
-                        $token->getValue()
-                    ));
-                }
-
-                $this->proceedOperator($token);
-                $this->stack->push($token);
-                break;
-
-            default:
-                throw new UnknownTokenException(sprintf(
-                    'Unknown token: "%s".',
-                    $token->getValue()
-                ));
-        }
-    }
-
-    /**
-     * @param $token
-     * @throws \Exception
-     */
-    private function proceedOperator(Token $token)
-    {
-        if (!array_key_exists($token->getValue(), $this->operators)) {
-            throw new UnknownOperatorException(sprintf(
-                'Unknown operator: "%s".',
-                $token->getValue()
-            ));
-        }
-
-        /** @var Operand $operator */
-        $operator = $this->operators[$token->getValue()];
-
-        while (!$this->stack->isEmpty()) {
-            $top = $this->stack->top();
-
-            if ($top->getType() == Token::OPERATOR) {
-                /** @var Operand $operator */
-                $operator = $this->operators[$top->getValue()];
-                $priority = $operator->getPriority();
-                if ( $operator->getAssociation() == Operand::RIGHT_ASSOCIATED) {
-                    if (($priority > $operator->getPriority())) {
-                        $this->queue->push($this->stack->pop());
-                    } else {
-                        return;
-                    }
-                } else {
-                    if (($priority >= $operator->getPriority())) {
-                        $this->queue->push($this->stack->pop());
-                    } else {
-                        return;
-                    }
-                }
-            } elseif ($top->getType() == Token::STRING) {
-                $this->queue->push($this->stack->pop());
-            } else {
-                return;
-            }
-        }
-    }
-
-    /**
-     * @param  \SplQueue  $expression
-     * @return mixed
-     * @throws \Exception
-     */
-    private function calculateReversePolishNotation(\SplQueue $expression)
-    {
-        $this->stack = new \SplStack();
-        /** @var Token $token */
-        foreach ($expression as $token) {
-            switch ($token->getType()) {
-                case Token::NUMBER :
-                    $this->stack->push($token);
-                    break;
-
-                case Token::OPERATOR:
-                    /** @var Operand $operator */
-                    $operator = $this->operators[$token->getValue()];
-                    if ($operator->getType() == Operand::BINARY) {
-                        $arg2 = $this->stack->pop()->getValue();
-                        $arg1 = $this->stack->pop()->getValue();
-                    } else {
-                        $arg2 = null;
-                        $arg1 = $this->stack->pop()->getValue();
-                    }
-                    $callback = $operator->getCallback();
-
-                    $this->stack->push(new Token(Token::NUMBER, (call_user_func($callback, $arg1, $arg2))));
-                    break;
-
-                case Token::FUNC:
-                    /** @var Func $function */
-                    $callback = $this->functions[$token->getValue()];
-                    $arg = $this->stack->pop()->getValue();
-                    $this->stack->push(new Token(Token::NUMBER, (call_user_func($callback, $arg))));
-                    break;
-
-                default:
-                    throw new UnknownTokenException(sprintf(
-                        'Unknown token: "%s".',
-                        $token->getValue()
-                    ));
-            }
-        }
-
-        $result = $this->stack->pop()->getValue();
-
-        if (!$this->stack->isEmpty()) {
-            throw new IncorrectExpressionException('Incorrect expression.');
-        }
+        $lexer = new Lexer($this->tokenFactory);
+        $tokensStream = $lexer->stringToTokensStream($expression);
+        $tokens = $lexer->buildReversePolishNotation($tokensStream);
+        $calculator = new Calculator();
+        $result = $calculator->calculate($tokens);
 
         return $result;
     }