function isLoggedIn() {

    var text = bgTools.getCookie('BGUSER');
    var isLoggedIn = false;
    var data = null;

    if(typeof text == 'undefined' || text === null) {
        isLoggedIn = false;
    } else {
        data        = bgTools.Json.decode(text);
        isLoggedIn    = data.loggedIn;
    }

    return isLoggedIn;
}

function showUserContent() {

    var text = bgTools.getCookie('BGUSER');
    var data = null;
    var dataChanged = false;
    var loggedIn = false;
    // not logged in
    if(typeof text == 'undefined' || text === null) {
        loggedIn = false;
    } else {
        data        = bgTools.Json.decode(text);
        loggedIn    = data.loggedIn;
    }

    // user is not logged in
    if(loggedIn) {
        var welcome = document.getElementById('user_welcome');
        welcome.innerHTML = 'Willkommen ' + data.nickname + '!';
        welcome.style.display = 'block';
        // user is logged in, so show logout link
        document.getElementById('logout').style.display = 'block';
    }

    // check that the cookie was read
    if(typeof data == 'undefined' || data === null) {
        return;
    }

    var userMessages = data.messages;

    var messages = document.getElementById('userMessages');
    if(userMessages && userMessages.length > 0) {
        messages.style.display = 'block';

        var message = null, messageText = null;
        var text = null;
        for(var i=0;i<userMessages.length;i++) {
            text = userMessages[i].text.replace(/\+/g,' ');
            message = document.createElement('div');
            message.className = 'userMsg'+userMessages[i]['class'];
            messageText = document.createElement('h2');
            messageText.innerHTML = text;
            message.appendChild(messageText);
            messages.appendChild(message);
        }
        data.messages = [];

        dataChanged = true;
    }
    if(dataChanged) {
        bgTools.setCookie('BGUSER', bgTools.Json.encode(data), 0, '/');
    }
}

function decreaseFont() {
    bgoBody = document.getElementById('content');
    if( bgoBody.style.fontSize ) {
        bgoBody.style.fontSize = parseInt(bgoBody.style.fontSize.replace('px','')) - 1  + 'px';
    } else {
        bgoBody.style.fontSize = '11px'
    }
}

function increaseFont() {
    bgoBody = document.getElementById('content');
    if( bgoBody.style.fontSize ) {
        bgoBody.style.fontSize = parseInt(bgoBody.style.fontSize.replace('px',''))  + 1  + 'px';
    } else {
        bgoBody.style.fontSize = '13px'
    }
}

function resetFont() {
    bgoBody = document.getElementById('content');
    bgoBody.style.fontSize = '12px'
}