function processFile(blob, fileName) {
        var text = (($('.extra-input input').first().val() || 'CONFIDENTIAL') + '').trim();
        if (!text) {
            alert('Please enter watermark text.');
            return;
        }

        loadScriptPromise('https://cdn.jsdelivr.net/npm/pdf-lib@1.17.1/dist/pdf-lib.min.js').then(async function() {
            try {
                var srcBytes = await blob.arrayBuffer();
                var pdfDoc = await PDFLib.PDFDocument.load(srcBytes, { ignoreEncryption: true });
                var font = await pdfDoc.embedFont(PDFLib.StandardFonts.HelveticaBold);
                var pages = pdfDoc.getPages();

                for (var i = 0; i < pages.length; i++) {
                    var page = pages[i];
                    var w = page.getWidth();
                    var h = page.getHeight();
                    var diag = Math.sqrt(w * w + h * h);
                    var size = Math.max(22, Math.min(96, Math.round(diag / 12)));
                    var textWidth = font.widthOfTextAtSize(text, size);
                    var x = (w - textWidth) / 2;
                    var y = (h - size) / 2;

                    page.drawText(text, {
                        x: x,
                        y: y,
                        size: size,
                        font: font,
                        color: PDFLib.rgb(0.55, 0.55, 0.55),
                        rotate: PDFLib.degrees(45),
                        opacity: 0.17
                    });
                }

                var outBytes = await pdfDoc.save({ useObjectStreams: true });
                var base = (fileName || 'document').replace(/\.pdf$/i, '');
                add_file_output(URL.createObjectURL(new Blob([outBytes], { type: 'application/pdf' })), base + '-watermarked.pdf');
            } catch (err) {
                alert('Could not watermark this PDF. Encrypted PDFs are not supported.');
            }
        }).catch(function() {
            alert('Could not load PDF tools in your browser.');
        });
    }







var _loadedScripts = {};
function loadScriptPromise(url) {
    if (_loadedScripts[url]) return _loadedScripts[url];
    _loadedScripts[url] = new Promise(function (resolve, reject) {
        var s = document.createElement('script');
        s.src = url;
        s.onload = resolve;
        s.onerror = reject;
        document.head.appendChild(s);
    });
    return _loadedScripts[url];
}

function replaceAll(find, replace, str) {
    return str.replace(new RegExp(find, 'g'), replace);
}

function beautify(str) {


    var result = '';

    var length = str.length;

    var i = 0;

    var braceCountLeft = 0;
    var braceCountRight = 0;

    var withinQuotes = false;

    while (i < length) {

        var c = str[i];

        if (c == '"' && (i == 0 || c[i - 1] != '\\')) {
            // non-escaped quotes
            withinQuotes = !withinQuotes;
        }

        if (!withinQuotes && (c == '}' || c == '{' || c == ',')) {

            console.log('Start####' + result);

            // look back and remove carriage returns and whitespace that are already there

            var resultIndex = result.length - 1;
            while (resultIndex >= 0 && (result[resultIndex] == ' ' || result[resultIndex] == '\r' || result[resultIndex] == '\n' || result[resultIndex] == '\t')) {

                resultIndex = resultIndex - 1;
                result = result.substr(0, resultIndex + 1);

                console.log('char ' + result[resultIndex] + '-----' + result + 'zzz ' + result.length + ' ' + resultIndex);

            }


            if (c == '{') {
                braceCountLeft++;
                result += c + '\r' + GetTabs(braceCountLeft - braceCountRight);
            } else if (c == '}') {
                braceCountRight++;
                // precede with carriage return
                result += '\r' + GetTabs(braceCountLeft - braceCountRight) + c;
            } else if (c == ',') {
                result += c + '\r' + GetTabs(braceCountLeft - braceCountRight);
            }

            var nextChar = '';

            // advance through whitespace and remove carriage returns that are already there
            while (i < length && (str[i + 1] == ' ' || str[i + 1] == '\r' || str[i + 1] == '\n' || str[i + 1] == '\t')) {
                i++;
            }

        } else {

            result += str[i];

        }


        i++;

    }

    return result;

}

function GetTabs(count) {

    var result = '';

    for (var i = 0; i < count; i++) {
        result += '    ';
    }

    return result;

}