Use fileId instead of dir

(cherry picked from commit e9f9711421)

js/viewer/viewer.js

@@ -66,11 +66,11 @@ var odfViewer = {
 		var viewer;
 		if($('#isPublic').val() === '1') {
 			viewer = OC.generateUrl(
-				'apps/richdocuments/public?shareToken={shareToken}&fileName={fileName}&requesttoken={requesttoken}&dir={dir}',
+				'apps/richdocuments/public?shareToken={shareToken}&fileName={fileName}&requesttoken={requesttoken}&fileId={fileId}',
 				{
 					shareToken: $('#sharingToken').val(),
 					fileName: fileName,
-					dir: fileDir,
+					fileId: fileId,
 					requesttoken: OC.requestToken
 				}
 			);

lib/Controller/DocumentController.php

@@ -142,7 +142,7 @@ class DocumentController extends Controller {
 	 * @return TemplateResponse
 	 * @throws \Exception
 	 */
-	public function publicPage($shareToken, $fileName, $dir) {
+	public function publicPage($shareToken, $fileName, $fileId) {
 		try {
 			$share = $this->shareManager->getShareByToken($shareToken);
 			// not authenticated ?
@@ -156,7 +156,7 @@ class DocumentController extends Controller {
 
 			$node = $share->getNode();
 			if($node instanceof Folder) {
-				$item = $node->get($dir.'/'.$fileName);
+				$item = $node->getById($fileId)[0];
 			} else {
 				$item = $node;
 			}