Encode file to UTF-8 on fetch call

Signed-off-by: Raul <raul@nextcloud.com>

Author: Raudius

lib/Service/ApiService.php

@@ -30,6 +30,7 @@
 use OC\Files\Node\File;
 use OCA\Text\DocumentHasUnsavedChangesException;
 use OCA\Text\DocumentSaveConflictException;
+use OCA\Text\TextFile;
 use OCA\Text\VersionMismatchException;
 use OCP\AppFramework\Db\DoesNotExistException;
 use OCP\AppFramework\Http;
@@ -111,7 +112,7 @@ public function fetch($documentId, $sessionId, $sessionToken) {
 		if ($this->sessionService->isValidSession($documentId, $sessionId, $sessionToken)) {
 			$this->sessionService->removeInactiveSessions($documentId);
 			try {
-				$file = $this->documentService->getBaseFile($documentId);
+				$file = new TextFile($this->documentService->getBaseFile($documentId), $this->encodingService);
 			} catch (NotFoundException $e) {
 				return new NotFoundResponse();
 			}

lib/TextFile.php

@@ -0,0 +1,92 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2022 Raul Ferreira Fuentes <raul@nextcloud.com>
+ *
+ * @author Raul Ferreira Fuentes <raul@nextcloud.com>
+ *
+ * @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 OCA\Text;
+
+use OCA\Text\Service\EncodingService;
+use OCP\Files\NotFoundException;
+use OCP\Files\SimpleFS\ISimpleFile;
+
+/**
+ * Wrapper around a ISimpleFile object to ensure that it is correctly encoded (UTF-8) for the text app.
+ */
+class TextFile implements ISimpleFile {
+
+	/** @var ISimpleFile */
+	private $file;
+	/** @var EncodingService */
+	private $encodingService;
+
+	public function __construct(ISimpleFile $file, EncodingService $encodingService) {
+		$this->file = $file;
+		$this->encodingService = $encodingService;
+	}
+
+	public function getName() {
+		return $this->file->getName();
+	}
+
+	public function getSize() {
+		return $this->file->getSize();
+	}
+
+	public function getETag() {
+		return $this->file->getETag();
+	}
+
+	public function getMTime() {
+		return $this->file->getMTime();
+	}
+
+	public function getContent() {
+		$content = $this->encodingService->encodeToUtf8($this->file->getContent());
+		if (!$content) {
+			throw new NotFoundException('File not compatible with text because it could not be encoded to UTF-8.');
+		}
+
+		return $content;
+	}
+
+	public function putContent($data) {
+		return $this->file->putContent($data);
+	}
+
+	public function delete() {
+		$this->file->delete();
+	}
+
+	public function getMimeType() {
+		return 'text/plain;encoding=utf-8';
+	}
+
+	public function read() {
+		return $this->file->read();
+	}
+
+	public function write() {
+		return $this->file->write();
+	}
+}