var current = 0;
var slidesNumber = false;
var description = Array();
var slides = Array();

function goToSlide(number)
{
    document.getElementById('slide_number').innerHTML = number+1;
    
	id = slides[number];

	var link = '/material/player.php?id='+id;

	if ( number == 0 )
	{
	    link += '&first_slide=true';
	}
	if ( number == slidesNumber-1 )
	{
	    link += '&last_slide=true';
	}

	document.getElementById('player_frame').src = link;
	document.getElementById('slide-description_content').innerHTML = description[id];

	window.frames['slides_list-1'].document.getElementById('selection-'+current).src = '../images/ghost.gif';
	window.frames['slides_list-1'].document.getElementById('selection-'+number).src = '../images/slide_mask.gif';

	current = number;
}

function goNext()
{
	if ( slides[current+1] )
	{
    	goToSlide( current+1 );
	}

	window.frames['slides_list-1'].search(current);
}

function goPrevious()
{
	if ( slides[current-1] )
	{
    	goToSlide( current-1 );
	}

	window.frames['slides_list-1'].search(current);
}