feat(translations): Add translation provider API

Signed-off-by: Julius Härtl <jus@bitgrid.net>

1 files changed, 120 insertions, 0 deletions

diff --git a/lib/private/Translation/TranslationManager.php b/lib/private/Translation/TranslationManager.php
new file mode 100644
index 00000000000..ec829e83255
--- /dev/null
+++ b/lib/private/Translation/TranslationManager.php
@@ -0,0 +1,120 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2023 Julius Härtl <jus@bitgrid.net>
+ *
+ * @author Julius Härtl <jus@bitgrid.net>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+namespace OC\Translation;
+
+use InvalidArgumentException;
+use OC\AppFramework\Bootstrap\Coordinator;
+use OCP\IServerContainer;
+use OCP\PreConditionNotMetException;
+use OCP\Translation\IDetectLanguageProvider;
+use OCP\Translation\ITranslationManager;
+use OCP\Translation\ITranslationProvider;
+use Psr\Container\ContainerExceptionInterface;
+use Psr\Container\NotFoundExceptionInterface;
+use Psr\Log\LoggerInterface;
+use RuntimeException;
+use Throwable;
+
+class TranslationManager implements ITranslationManager {
+	/** @var ?ITranslationProvider[] */
+	private ?array $providers = null;
+
+	public function __construct(
+		private IServerContainer $serverContainer,
+		private Coordinator $coordinator,
+		private LoggerInterface $logger,
+	) {
+	}
+
+	public function getLanguages(): array {
+		$languages = [];
+		foreach ($this->getProviders() as $provider) {
+			$languages = array_merge($languages, $provider->getAvailableLanguages());
+		}
+		return $languages;
+	}
+
+	public function translate(string $text, ?string $fromLanguage, string $toLanguage): string {
+		if (!$this->hasProviders()) {
+			throw new PreConditionNotMetException('No translation providers available');
+		}
+
+		foreach ($this->getProviders() as $provider) {
+			if ($fromLanguage === null && $provider instanceof IDetectLanguageProvider) {
+				$fromLanguage = $provider->detectLanguage($text);
+			}
+
+			if ($fromLanguage === null) {
+				throw new InvalidArgumentException('Could not detect language');
+			}
+
+			try {
+				return $provider->translate($fromLanguage, $toLanguage, $text);
+			} catch (RuntimeException $e) {
+				$this->logger->warning("Failed to translate from {$fromLanguage} to {$toLanguage}", ['exception' => $e]);
+			}
+		}
+
+		throw new RuntimeException('Could not translate text');
+	}
+
+	public function getProviders(): array {
+		$context = $this->coordinator->getRegistrationContext();
+
+		if ($this->providers !== null) {
+			return $this->providers;
+		}
+
+		$this->providers = [];
+		foreach ($context->getTranslationProviders() as $providerRegistration) {
+			$class = $providerRegistration->getService();
+			try {
+				$this->providers[$class] = $this->serverContainer->get($class);
+			} catch (NotFoundExceptionInterface|ContainerExceptionInterface|Throwable $e) {
+				$this->logger->error('Failed to load translation provider ' . $class, [
+					'exception' => $e
+				]);
+			}
+		}
+
+		return $this->providers;
+	}
+
+	public function hasProviders(): bool {
+		$context = $this->coordinator->getRegistrationContext();
+		return !empty($context->getTranslationProviders());
+	}
+
+	public function canDetectLanguage(): bool {
+		foreach ($this->getProviders() as $provider) {
+			if ($provider instanceof IDetectLanguageProvider) {
+				return true;
+			}
+		}
+		return false;
+	}
+}