Add Bookmarks to PDF in PHP SDK

    private function _create_rest_api() {
        $credentials = json_decode(file_get_contents("./Credentials/credentials.json"), true);

        $configAuth = new Configuration();
        $configAuth->setAppKey($credentials['key']);
        $configAuth->setAppSid($credentials['id']);

        $this->pdfApi = new PdfApi(null, $configAuth);
    }

    public function __construct($config) {
        $this->configParams = $config;
        $this->_create_rest_api();
    }

    public function uploadDocument() {
        $filePath = $this->configParams['LOCAL_FOLDER'] . $this->configParams['PDF_DOCUMENT_NAME'];
        $fileData = file_get_contents($filePath);

        $response = $this->pdfApi->uploadFile($this->configParams['PDF_DOCUMENT_NAME'], $fileData);
        if ($response->getCode() === 200) {
            echo "Uploaded file: {$this->configParams['PDF_DOCUMENT_NAME']}\n";
        } else {
            echo "Failed to upload file.";
        }
    }

    public function downloadResult() {
        $response = $this->pdfApi->downloadFile($this->configParams['PDF_DOCUMENT_NAME']);
        $filePath = $this->configParams['LOCAL_FOLDER'] . $this->configParams['LOCAL_RESULT_DOCUMENT_NAME'];

        if ($response->getCode() === 200) {
            file_put_contents($filePath, $response->getContents());
            echo "Downloaded: $filePath\n";
        } else {
            echo "Failed to download file.";
        }
    }

    public function appendBookmarkLink() {
        $bookmarkLink = new Link(array('rel' => 'self'));
        $bookmarkColor = new Color(array('a' => 255, 'r' => 0, 'g' => 255, 'b' => 0));

        $newBookmark = new Bookmark(array(
            'title' => $this->configParams['NEW_BOOKMARK_TITLE'],
            'italic' => true,
            'bold' => false,
            'links' => array( $bookmarkLink ),
            'color' => $bookmarkColor,
            'action' => LinkActionType::GO_TO_ACTION,
            'level' => 1,
            'pageDisplayLeft' => 83,
            'pageDisplayTop' => 751,
            'pageDisplayZoom' => 2,
            'pageNumber' => $this->configParams['NEW_BOOKMARK_PAGE_NUMBER']
        ));

        $response = $this->pdfApi->postBookmark( $this->configParams['PDF_DOCUMENT_NAME'], $this->configParams['PARENT_BOOKMARK_FOR_APPEND'], array( $newBookmark ) );

        if ($response->getCode() === 200 && null !== $response->getBookmarks()->getList()) {
            $bookmarks = $response->getBookmarks()->getList();
            $addedBookmark = end($bookmarks);
            echo "Appended bookmark: {$addedBookmark->getLinks()[0]->getHref()} => {$addedBookmark->getTitle()}\n";
            return $addedBookmark;
        } else {
            echo "Failed to append bookmark.";
        }
    }

    function main() {
        global $configParams;

        try {
            $pdfBookmarks = new PdfBookmarks($configParams);
            $pdfBookmarks->uploadDocument();
            $pdfBookmarks->appendBookmarkLink();
            $pdfBookmarks->downloadResult();
        } catch (\Exception $e) {
            echo "Error: " . $e->getMessage() . "\n";
        }
    }