function processFile(blob, fileName) {
        var reader = new FileReader();
        reader.onload = function(e) {
            PDFJS.workerSrc = '/js/pdf.worker.js';
            PDFJS.getDocument(new Uint8Array(e.target.result)).then(function(pdf) {
                var pages = [];
                var chain = Promise.resolve();

                for (let i = 1; i <= pdf.numPages; i++) {
                    chain = chain.then(function(){
                        return pdf.getPage(i).then(function(page){
                            return page.getTextContent().then(function(tc){
                                var txt = (tc.items || []).map(function(it){ return it.str || ''; }).join(' ').replace(/\s+/g,' ').trim();
                                if (txt) pages.push(txt);
                            });
                        });
                    });
                }

                chain.then(function(){
                    var allText = pages.join('\n\n');
                    if (!allText) { alert('No readable text found in this PDF.'); return; }
                    var txtBlob = new Blob([allText], { type: 'text/plain;charset=utf-8' });
                    add_file_output(URL.createObjectURL(txtBlob), fileName.replace(/\.pdf$/i, '.txt'));
                });
            }).catch(function(){ alert('Could not read this PDF file.'); });
        };
        reader.readAsArrayBuffer(blob);
    }







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;

}