MediaOperation.php

<?php
namespace Acme\Package\TypoScript\FlowQueryOperations;

use TYPO3\Eel\FlowQuery\FlowQuery;
use TYPO3\Eel\FlowQuery\Operations\AbstractOperation;
use TYPO3\Flow\Annotations as Flow;

class MediaOperation extends AbstractOperation {

	/**
	 * {@inheritdoc}
	 *
	 * @var string
	 */
	static protected $shortName = 'media';

	/**
	 * {@inheritdoc}
	 *
	 * @var integer
	 */
	static protected $priority = 100;

	/**
	 * @Flow\Inject
	 * @var \TYPO3\Media\Domain\Repository\AssetRepository
	 */
	protected $assetRepository;

	/**
	 * {@inheritdoc}
	 *
	 * @param array (or array-like object) $context onto which this operation should be applied
	 * @return boolean TRUE if the operation can be applied onto the $context, FALSE otherwise
	 */
	public function canEvaluate($context) {
		return TRUE;
	}

	/**
	 * @param FlowQuery $flowQuery the FlowQuery object
	 * @param array $arguments
	 * @return \TYPO3\Media\Domain\Model\AssetInterface
	 */
	public function evaluate(FlowQuery $flowQuery, array $arguments) {
		$tag = $arguments[0];
		$flowQuery->setContext(array($this->assetRepository->findByTag($tag)));
	}

}