function getResponse(username) {
    const responses = {
        'GinsStreamCorner': `${userName} ist zu breit für den Stream`,
        'default': `${userName} ist leider nicht da :(`
    };

    const inChat = isInChat(username);
    if (inChat) {
        return 'Er ist da! :D';
    }

    const key = responses[userName];
    if (key !== undefined) {
        return key;
    } else {
        return responses['default'];
    }
}

function isInChat(username) {
    const url = 'https://tmi.twitch.tv/group/user/sic_smash/chatters';

    const xmlHttp = new XMLHttpRequest();
    xmlHttp.open( "GET", url, false);
    xmlHttp.send( null );
    const response = xmlHttp.responseText;

    const json = JSON.parse(response);
    const chatters = json.chatters;
    if (chatters.moderators.includes(username) {
        return true;
    }
    if (chatters.vips.includes(username) {
        return true;
    }
    if (chatters.viewers.includes(username) {
        return true;
    }
    return false;
}