Dynamically loading iframe to print

iframe.js

    function prepareIframe(src) {

        var iframeDocument, iframeContent;
        var iframe = document.getElementById("iframe-print");

        if (!iframe || !src)  {
            return;
        }

        iframe.src = src;

        // Apply delay to let iframe load content
        $timeout(function() {

            if (iframe.contentDocument) {
                iframeDocument = iframe.contentDocument;
            } else if (iframe.contentWindow) {
                iframeDocument = iframe.contentWindow.document; // IE
            }
            // Print iframe content
            if (iframeDocument) {
                iframeContent = iframeDocument.getElementsByTagName('html')[0].innerHTML;
            }

            // Send iframe content for print
            printIframe(iframeContent);

        }, 4000);
    }

    // Print content from iframe
    function printIframe(iframeHtml) {

         var openWindow = window.open("", "Print chapter", "attributes");
             openWindow.document.write(iframeHtml);
             openWindow.document.close();
             openWindow.focus();
             openWindow.print();
             openWindow.close();
    }

    /**
     * [Print - delegated call to browser page print]
     *
     */
    $scope.printClickHandler = function($event, a)
    {
        $event.preventDefault();
        $event.stopPropagation();

        // Print current page by default
        var action = a || 'current';

        if (a == 'current') {
            $window.print();
        } else {
            var iframeUrl = "http://url.for.iframe/";
            prepareIframe(iframeUrl);
        }
    };