var httpGet = function(url, type, callback) {
    var xmlHttp = new XMLHttpRequest();
    xmlHttp.open("GET", url);
    xmlHttp.responseType = type;

    xmlHttp.onload = function() {
        callback(xmlHttp.response);
    };

    xmlHttp.send(null);
};

var getPlantUMLOnlineURL = function(server, format, text) {
    var s = unescape(encodeURIComponent(text));
    var arr = [];
    for (var i = 0; i < s.length; i++) {
        arr.push(s.charCodeAt(i));
    }

    var compressor = new Zopfli.RawDeflate(arr);
    var compressed = compressor.compress();
    var url = server + "/" + format + "/" + encode64_(compressed);
    return url;
};

var renderPlantUMLOnline = function(server, format, text, callback, data) {
    var url = getPlantUMLOnlineURL(server, format, text);

    if (format == 'png') {
        httpGet(url, 'blob', function(resp) {
            var blob = resp;
            var reader = new FileReader();
            reader.onload = function () {
                var dataUrl = reader.result;
                var png = dataUrl.substring(dataUrl.indexOf(',') + 1);
                callback(data, format, png);
            };

            reader.readAsDataURL(blob);
        });
    } else if (format == 'svg') {
        httpGet(url, 'text', function(resp) {
            callback(data, format, resp);
        });
    }
};