OrderedCollection

OrderedCollection.php

<?php declare(strict_types=1);

namespace App\Library\DataStructures;

use Ds\Vector;
use Iterator;
use IteratorAggregate;

final class OrderedCollection implements IteratorAggregate
{
	/**
	 * @var bool
	 */
	private $isOrdered = true;

	/**
	 * @var Vector
	 */
	private $items;

	/**
	 * @var callable
	 */
	private $comparator;

	public function __construct(callable $comparator)
	{
		$this->comparator = $comparator;
		$this->items = new Vector();
	}

	public function push($item): void
	{
		$this->items->push($item);
		$this->isOrdered = false;
	}

	public function getIterator(): Iterator
	{
		if (! $this->isOrdered) {
			$this->items->sort($this->comparator);
			$this->isOrdered = true;
		}

		yield from clone $this->items;
	}
}