<?php
namespace FluidTYPO3\Vhs\ViewHelpers\Media;

/*
 * This file is part of the FluidTYPO3/Vhs project under GPLv2 or later.
 *
 * For the full copyright and license information, please read the
 * LICENSE.md file that was distributed with this source code.
 */

use TYPO3\CMS\Core\Utility\GeneralUtility;
use TYPO3\CMS\Fluid\Core\ViewHelper\AbstractViewHelper;

/**
 * Returns the extension of the provided file
 *
 * @author Björn Fromme <fromme@dreipunktnull.com>, dreipunktnull
 * @package Vhs
 * @subpackage ViewHelpers\Media
 */
class ExtensionViewHelper extends AbstractViewHelper {

	/**
	 * Initialize arguments.
	 *
	 * @return void
	 * @api
	 */
	public function initializeArguments() {
		$this->registerArgument('file', 'string', 'Path to the file to determine extension for.', FALSE);
	}

	/**
	 * @return string
	 */
	public function render() {

		$filePath = $this->arguments['file'];

		if (TRUE === empty($filePath)) {
			$filePath = $this->renderChildren();

			if (NULL === $filePath) {
				return '';
			}
		}

		$file = GeneralUtility::getFileAbsFileName($filePath);

		$parts = explode('.', basename($file));

		// file has no extension
		if (1 === count($parts)) {
			return '';
		}

		$extension = strtolower(array_pop($parts));

		return $extension;
	}

}