var page_size = 860;
var current_page = 0;
var transition = false;

function OnPageTransition()
{
	transition = false;
}

function SetButtons()
{
	var frame = jQuery('#frame');
	if (current_page > 0)
		frame.removeClass('first_page');
	else
		frame.addClass('first_page');
	
	num_pages = jQuery('#content_container').attr('offsetWidth') / page_size;
	if (current_page < num_pages - 1)
		frame.removeClass('last_page');
	else
		frame.addClass('last_page');
}

function NextPage()
{
	if (transition == false)
	{
		current_page = current_page + 1;
		jQuery('#content_container').animate({
			left: 0 - current_page * page_size
		}, 500, 'swing', OnPageTransition);
		
		transition = true;
	}

        SetButtons();
}

function PreviousPage()
{
    if (transition == false)
    {
        current_page = current_page - 1;
        jQuery('#content_container').animate({
                left: 0 - current_page * page_size
        }, 500, 'swing', OnPageTransition);

        transition = true;
    }

	SetButtons();
}

function ToggleFrame()
{
	var frame_element;
	frame_element = jQuery('.minimize');
	frame_element.toggleClass('closed');
}