var AmiMisuzuAuth = function(refreshUrl) {
    var userId = undefined,
        authToken = undefined;

    return {
        getUserId: function() { return userId; },
        getAuthToken: function() { return authToken; },
        getInfo: function() {
            return {
                method: 'Misuzu',
                token: authToken,
            };
        },
        getHttpAuth: function() {
            return 'Misuzu ' + authToken;
        },
        refresh: function(callback) {
            var xhr = new XMLHttpRequest;
            xhr.onload = function() {
                if(xhr.status === 200) {
                    var data = JSON.parse(xhr.responseText);
                    if(data.ok === true) {
                        userId = data.usr.toString();
                        authToken = data.tkn;
                    }

                    callback(data);
                } else
                    callback({ok: null});
            };
            xhr.onerror = function() {
                callback({ok: null});
            };
            xhr.open('GET', refreshUrl);
            xhr.withCredentials = true;
            xhr.send();
        },
    };
};