A Flow HTTP component for multilanguage

DetectLanguageComponent.php

<?php
namespace Acme\Foo\Http;

use TYPO3\Flow\Annotations as Flow;
use TYPO3\Flow\Http\Component\ComponentContext;
use TYPO3\Flow\Http\Component\ComponentInterface;
use TYPO3\Flow\I18n\Detector;
use TYPO3\Flow\I18n\Locale;

/**
 * A HTTP component that detects and sets the current locale from request URI, cookie or Accept-Language header.
 */
class DetectLanguageComponent implements ComponentInterface
{
	/**
	 * @Flow\Inject
	 * @var Detector
	 */
	protected $localeDetector;

	/**
	 * @Flow\Inject
	 * @var \TYPO3\Flow\I18n\Service
	 */
	protected $i18nService;

	/**
	 * @var array
	 */
	protected $options;

	protected static $defaultOptions = array(
		'uriPosition' => 0,
		'cookieName' => 'locale'
	);

	/**
	 * @param array $options The component options
	 */
	public function __construct(array $options = array())
	{
		$this->options = array_merge(self::$defaultOptions, $options);
	}

	/**
	 * @param ComponentContext $componentContext
	 * @return void
	 */
	public function handle(ComponentContext $componentContext)
	{
		$httpRequest = $componentContext->getHttpRequest();
		$requestPath = $httpRequest->getUri()->getPath();
		$firstRequestPathSegment = explode('/', ltrim($requestPath, '/'))[$this->options['uriPosition']];

		if ($firstRequestPathSegment !== '') {
			try {
				$uriLocale = $this->localeDetector->detectLocaleFromTemplateLocale(new \TYPO3\Flow\I18n\Locale($firstRequestPathSegment));
				$this->i18nService->getConfiguration()->setCurrentLocale($uriLocale);

				return;
			} catch (\TYPO3\Flow\I18n\Exception\InvalidLocaleIdentifierException $exception) {
			}
		}

		$localeCookie = $httpRequest->getCookie($this->options['cookieName']);
		if ($localeCookie !== null) {
			try {
				$cookieLocale = $this->localeDetector->detectLocaleFromTemplateLocale(new \TYPO3\Flow\I18n\Locale($localeCookie));
				$this->i18nService->getConfiguration()->setCurrentLocale($cookieLocale);
				return;
			} catch (\TYPO3\Flow\I18n\Exception\InvalidLocaleIdentifierException $exception) {
			}
		}

		$detectedLocale = $this->localeDetector->detectLocaleFromHttpHeader($httpRequest->getHeader('Accept-Language'));
		if (!$detectedLocale instanceof Locale) {
			return;
		}
		$this->i18nService->getConfiguration()->setCurrentLocale($detectedLocale);
	}
}