1: <?php
 2: 
 3: namespace BN\Compiler\Parser;
 4: 
 5: use BN\Collections\Stack;
 6: use BN\Collections\Queue;
 7: use BN\Compiler\Token\Token;
 8: use BN\Compiler\Token\TokenType;
 9: 
10: class QueueAccumulator
11: {
12:     private $stack;
13:     private $queue;
14:     private $errorHandler;
15:     private $continueInParsing;
16: 
17:     public function __construct(ParserErrorHandler $errorHandler)
18:     {
19:         $this->errorHandler = $errorHandler;
20:         $this->stack = new Stack();
21:     }
22: 
23:     public function init()
24:     {
25:         $this->continueInParsing = true;
26:         $this->queue = new Queue();
27:         $this->stack->clear();
28:     }
29: 
30:     public function noError()
31:     {
32:         return $this->continueInParsing;
33:     }
34: 
35:     public function pushTokenToStack(Token $token)
36:     {
37:         $this->stack->push($token);
38:     }
39: 
40:     public function popTokenFromStack()
41:     {
42:         return $this->stack->pop();
43:     }
44: 
45:     public function isStackEmpty()
46:     {
47:         return $this->stack->isEmpty();
48:     }
49: 
50:     public function isOperatorAtTopOfStack()
51:     {
52:         return $this->isTypeAtStackPeek(TokenType::OPERATOR)
53:             || $this->isTypeAtStackPeek(TokenType::ASSIGN);
54:     }
55: 
56:     public function isTypeAtStackPeek($tokenType)
57:     {
58:         return $this->stack->peek()->type == $tokenType;
59:     }
60: 
61:     public function valueAtStackPeek()
62:     {
63:         return $this->stack->peek()->value;
64:     }
65: 
66:     public function pushTokenFromStackToQueue()
67:     {
68:         $this->pushTokenToQueue($this->stack->pop());
69:     }
70: 
71:     public function pushTokenToQueue(Token $token)
72:     {
73:         $this->queue->push($token);
74:     }
75: 
76:     public function stopParsing($method, $arg = null)
77:     {
78:         $this->stack->clear();
79:         $this->continueInParsing = false;
80:         $this->errorHandler->$method($arg);
81:     }
82: 
83:     public function getResult()
84:     {
85:         if ($this->noError()) {
86:             return $this->queue;
87:         } else {
88:             return false;
89:         }
90:     }
91: }
92: