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    <h3>Editing: LoggingTranslator.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier &lt;fabien@symfony.com&gt;
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\Translation;

use Psr\Log\LoggerInterface;
use Symfony\Component\Translation\Exception\InvalidArgumentException;
use Symfony\Contracts\Translation\LocaleAwareInterface;
use Symfony\Contracts\Translation\TranslatorInterface;

/**
 * @author Abdellatif Ait boudad &lt;a.aitboudad@gmail.com&gt;
 */
class LoggingTranslator implements TranslatorInterface, TranslatorBagInterface, LocaleAwareInterface
{
    private $translator;
    private $logger;

    /**
     * @param TranslatorInterface&amp;TranslatorBagInterface&amp;LocaleAwareInterface $translator The translator must implement TranslatorBagInterface
     */
    public function __construct(TranslatorInterface $translator, LoggerInterface $logger)
    {
        if (!$translator instanceof TranslatorBagInterface || !$translator instanceof LocaleAwareInterface) {
            throw new InvalidArgumentException(sprintf('The Translator &quot;%s&quot; must implement TranslatorInterface, TranslatorBagInterface and LocaleAwareInterface.', get_debug_type($translator)));
        }

        $this-&gt;translator = $translator;
        $this-&gt;logger = $logger;
    }

    /**
     * {@inheritdoc}
     */
    public function trans(?string $id, array $parameters = [], ?string $domain = null, ?string $locale = null)
    {
        $trans = $this-&gt;translator-&gt;trans($id = (string) $id, $parameters, $domain, $locale);
        $this-&gt;log($id, $domain, $locale);

        return $trans;
    }

    /**
     * {@inheritdoc}
     */
    public function setLocale(string $locale)
    {
        $prev = $this-&gt;translator-&gt;getLocale();
        $this-&gt;translator-&gt;setLocale($locale);
        if ($prev === $locale) {
            return;
        }

        $this-&gt;logger-&gt;debug(sprintf('The locale of the translator has changed from &quot;%s&quot; to &quot;%s&quot;.', $prev, $locale));
    }

    /**
     * {@inheritdoc}
     */
    public function getLocale()
    {
        return $this-&gt;translator-&gt;getLocale();
    }

    /**
     * {@inheritdoc}
     */
    public function getCatalogue(?string $locale = null)
    {
        return $this-&gt;translator-&gt;getCatalogue($locale);
    }

    /**
     * {@inheritdoc}
     */
    public function getCatalogues(): array
    {
        return $this-&gt;translator-&gt;getCatalogues();
    }

    /**
     * Gets the fallback locales.
     *
     * @return array
     */
    public function getFallbackLocales()
    {
        if ($this-&gt;translator instanceof Translator || method_exists($this-&gt;translator, 'getFallbackLocales')) {
            return $this-&gt;translator-&gt;getFallbackLocales();
        }

        return [];
    }

    /**
     * Passes through all unknown calls onto the translator object.
     */
    public function __call(string $method, array $args)
    {
        return $this-&gt;translator-&gt;{$method}(...$args);
    }

    /**
     * Logs for missing translations.
     */
    private function log(string $id, ?string $domain, ?string $locale)
    {
        if (null === $domain) {
            $domain = 'messages';
        }

        $catalogue = $this-&gt;translator-&gt;getCatalogue($locale);
        if ($catalogue-&gt;defines($id, $domain)) {
            return;
        }

        if ($catalogue-&gt;has($id, $domain)) {
            $this-&gt;logger-&gt;debug('Translation use fallback catalogue.', ['id' =&gt; $id, 'domain' =&gt; $domain, 'locale' =&gt; $catalogue-&gt;getLocale()]);
        } else {
            $this-&gt;logger-&gt;warning('Translation not found.', ['id' =&gt; $id, 'domain' =&gt; $domain, 'locale' =&gt; $catalogue-&gt;getLocale()]);
        }
    }
}
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