Mfonte\Base62x\Compression\Huffman\HuffmanNodeQueue

Complexity

Total Complexity

8

Size/Duplication

Total Lines	47
Duplicated Lines	0 %

Importance

Changes	1
Bugs	0	Features	0

3 Methods

Rating	Name	Duplication	Size	Complexity
A	popTwoNodes()	0	9	2
A	getOnlyNode()	0	6	2
A	addNode()	0	13	4

<?php

namespace Mfonte\Base62x\Compression\Huffman;

use Mfonte\Base62x\Exception\CompressionException;

/**
 *	A queue of Huffman Nodes that need to be incorporated into a tree.
 */
class HuffmanNodeQueue
{
    private $nodes = [];

    /**
     * put the new node into the queue, keeping it in order by weight
     * NOTE: schliemel going on here!
     */
    public function addNode(HuffmanNode $node)
    {
        if (\count($this->nodes) == 0) {
            $this->nodes = [$node];

            return;
        }

        $index = 0;
        while (isset($this->nodes[$index]) && $this->nodes[$index]->getWeight() < $node->getWeight()) {
            ++$index;
        }
        array_splice($this->nodes, $index, 0, [$node]);
    }

    /**
     * 	get the two nodes with the lowest weights from the front of the queue.
     */
    public function popTwoNodes()
    {
        if (\count($this->nodes) > 1) {
            $first = array_shift($this->nodes);
            $second = array_shift($this->nodes);

            return [$first, $second];
        } else {
            return false;
        }
    }

    /**
     * 	once there's only one node left, extract it.
     */
    public function getOnlyNode()
    {
        if (\count($this->nodes) == 1) {
            return $this->nodes[0];
        } else {
            throw new CompressionException('huffman', 'Wrong number of nodes. Only call getOnlyNode when exactly one node exists.');
        }
    }
}