function PresentGroupInviteOptions( rgFriendsToInvite )
{
    // this deferred will succeed if an invite is succesfully sent, fail if the user dismisses the modal or the invite AJAX fails
    var deferred = new jQuery.Deferred();

    var Modal = ShowDialog( 'In Ihre Gruppe einladen', '<div class="group_invite_throbber"><img src="https://steamcommunity-a.akamaihd.net/public/images/login/throbber.gif"></div>' );
    var $ListElement = $J('<div/>', {'class': 'newmodal_content_innerbg'} );

    var bBulkFriendInvite = false;
    var steamIDInvitee = g_rgProfileData['steamid'];
    var strProfileURL = g_rgProfileData['url'];

    // see if this is a request to bulk invite a group of friends
    if ( rgFriendsToInvite && rgFriendsToInvite instanceof Array )
    {
        if ( rgFriendsToInvite.length == 1 )
        {
            steamIDInvitee = rgFriendsToInvite[0];
            strProfileURL = 'https://steamcommunity.com/profiles/' + steamIDInvitee + '/';
        }
        else
        {
            // true bulk invite
            steamIDInvitee = rgFriendsToInvite;
            bBulkFriendInvite = true;
        }
    }

    // if the modal is dismissed , we'll cancel the deferred object.  We capture this in a closure so that we can dismiss the modal without affecting
    //  the deferred object if the user actually picks something (in which case the deferred object will be the success of the AJAX invite action)
    var fnOnModalDismiss = function() { deferred.reject() };

    $J.get( strProfileURL + 'ajaxgroupinvite?new_profile=1' + ( bBulkFriendInvite ? '&bulk=1' : '' ), function( html ) {
        Modal.GetContent().find( '.newmodal_content').html(''); // erase the throbber
        Modal.GetContent().find( '.newmodal_content').append( $ListElement );
        $ListElement.html( html );
        Modal.AdjustSizing();
        $ListElement.children( '.group_list_results' ).children().each( function () {
            var groupid = this.getAttribute( 'data-groupid' );
            if ( groupid )
            {
                $J(this).click( function() {
                    fnOnModalDismiss = function () {;}; // don't resolve the deferred on modal dismiss anymore, user has picked something
                    InviteUserToGroup( Modal, groupid, steamIDInvitee)
                    .done( function() { deferred.resolve(); } )
                    .fail( function() { deferred.reject(); } );
                } );
            }
        });
    });

    Modal.done( function() {fnOnModalDismiss();} );

    return deferred.promise();
}





function InviteUserToGroup( Modal, groupID, steamIDInvitee )
{
    var params = {
        json: 1,
        type: 'groupInvite',
        group: groupID,
        sessionID: g_sessionID
    };

    if ( !steamIDInvitee.length )
    {
        ShowAlertDialog( 'Fehler', 'Sie haben keine Freunde ausgewählt.' );
        return;
    }

    if ( steamIDInvitee instanceof Array )
        params.invitee_list = V_ToJSON( steamIDInvitee );
    else
        params.invitee = steamIDInvitee;

    return $J.ajax( { url: 'https://steamcommunity.com/actions/GroupInvite',
        data: params,
        type: 'POST'
    } ).done( function( data ) {
        Modal && Modal.Dismiss();

        var strMessage = 'Einladung verschickt!';
        if ( steamIDInvitee instanceof Array && steamIDInvitee.length > 1 )
            strMessage = 'Einladungen verschickt!';

        ShowAlertDialog( 'In Ihre Gruppe einladen', strMessage );
    }).fail( function( data ) {
        Modal && Modal.Dismiss();

        var rgResults = data.responseJSON;

        var strModalTitle = 'Gruppeneinladung fehlgeschlagen';
        var strAccountListModal = '<div class="ctnClanInviteErrors">';
        strAccountListModal += rgResults.results ? rgResults.results : 'Bei der Verarbeitung Ihrer Anfrage ist ein Fehler aufgetreten. Bitte versuchen Sie es erneut.';
        if ( rgResults.rgAccounts )
        {
            strAccountListModal += '<div class="ctnClanInviteErrors"><table class="clanInviteErrorTable" ><thead><tr><th class="inviteTablePersona" >Eingeladener Spieler</th><th class="inviteTableError">Fehler</th></tr></thead><tbody>';
            var cAccounts = 0;
            $J.each( rgResults.rgAccounts, function( accountid, rgError ){
                strAccountListModal += '<tr>';
                strAccountListModal += '<td class="inviteTablePersona ellipsis">' + rgError.persona + '</td>';
                strAccountListModal += '<td class="inviteTableError">' + rgError.strError + "</td>";
                strAccountListModal += '</tr>';

                if ( typeof SelectNone != 'undefined' )
                {
                    SelectNone();
                    $J( '#fr_' + accountid ).addClass( 'groupInviteFailed' );
                }

                cAccounts++;
            } );
            strAccountListModal += '</tbody></table>';

            if ( cAccounts > 1 )
                strModalTitle = 'Gruppeneinladungen fehlgeschlagen';

        }
        strAccountListModal +='</div>';
        ShowAlertDialog( strModalTitle, strAccountListModal );
    });
}



function ManageFriendsInviteToGroup( $Form, groupid )
{
    $Form.find('input[type="checkbox"]');
    var rgFriendSteamIDs = [];
    $Form.find( 'input[type=checkbox]' ).each( function() {
        if ( this.checked )
            rgFriendSteamIDs.push( $J(this).attr( 'data-steamid' ) );
    } );
    if ( rgFriendSteamIDs.length > 0 )
    {
        if ( groupid )
        {
            // specific group
            InviteUserToGroup( null /* no modal window */, groupid, rgFriendSteamIDs ).done( function() {
                $Form.find('input[type=checkbox]').prop( 'checked', false );
            });
        }
        else
        {
            // ask the user which group to invite to
            PresentGroupInviteOptions( rgFriendSteamIDs).done( function() {
                $Form.find('input[type=checkbox]').prop( 'checked', false );
            });
        }
    }
    else
    {
        ShowAlertDialog( 'In Ihre Gruppe einladen', 'Sie haben keine Freunde ausgewählt.' );
    }
}