var divHeight = 0;
var divPosition = 676;
var aagSpeed = 300;
var scrollSpeed = 20;
var t, s, videos;
var subTab = "A";
var subTab2 = "A2";
var sTime = Array();
sTime['GT'] = "A";
sTime['ST'] = "A";
sTime['PL'] = "A";
var screenTop = 0;
var pdfTracks = Array();
pdfTracks['GT'] = '<a href="pdf/Shift_Gen_Breakouts.pdf" target="_blank">Download PDF</a>';
pdfTracks['ST'] = '<a href="pdf/Shift_Student_Breakouts.pdf" target="_blank">Download PDF</a>';
pdfTracks['PL'] = '<a href="pdf/Shift_PL_Breakouts.pdf" target="_blank">Download PDF</a>';


/* Initialization code. */
if (window.addEventListener)
	window.addEventListener('DOMMouseScroll', wheel, false);
window.onmousewheel = document.onmousewheel = wheel;

function openAAG()
{
	var overlay = document.getElementById('pageOverlay');
	overlay.style.display = "block";
	
	slideAAGUp();
}

function slideAAGUp()
{
	var overlay = document.getElementById('pageOverlay');
	divHeight = divHeight + aagSpeed;
	divPosition = divPosition - aagSpeed;
	overlay.style.height = divHeight + "px";
	overlay.style.top = divPosition + "px";
	aagSpeed = (divPosition - 120) / 2;
	if(divHeight < 545)
	{
		t = setTimeout("slideAAGUp()", 50);
	}
}

function closeAAG()
{
	slideAAGDown();
}

function slideAAGDown()
{
	var overlay = document.getElementById('pageOverlay');
	divHeight = divHeight - aagSpeed;
	divPosition = divPosition + aagSpeed;
	if(divHeight < 1)
	{
		divHeight = 0;
		divPosition = 676;
	}
	overlay.style.height = divHeight + "px";
	overlay.style.top = divPosition + "px";
	aagSpeed = (divPosition -120) / 2;
	if(divHeight > 1)
	{
		t = setTimeout("slideAAGDown()", 50);
	}
	else
	{
		overlay.style.display = "none";
	}
}


function toggleSession(id)
{
	var div = document.getElementById(id);
	if(div.className == "open")
	{
		div.className = "closed";
	}
	else
	{
		div.className = "open";
	}
	resetSliderButtons();
}


function displayBreakouts(cat, time)
{
	document.getElementById('Track-'+cat+'-'+sTime[cat]).className = "";
	document.getElementById('TrackList-'+cat+'-'+sTime[cat]).className = "hide";
	document.getElementById('Track-'+cat+'-'+time).className = "selected";
	document.getElementById('TrackList-'+cat+'-'+time).className = "show";
	sTime[cat] = time;
	resetSliderButtons();
}

function scrollUp()
{
	if(screenTop < 0)
	{
		screenTop = screenTop + scrollSpeed + 20;
		document.getElementById('screen').style.top = screenTop + "px";
		s = setTimeout('scrollUp()', 10);
		document.getElementById('moreSpan').className = "on";
	}
	else
	{
		document.getElementById('previousSpan').className = "";
	}
}

function scrollDown()
{
	if(screenTop > document.getElementById('subBody').offsetHeight - document.getElementById('screen').offsetHeight)
	{
		screenTop = screenTop - scrollSpeed - 20;
		document.getElementById('screen').style.top = screenTop + "px";
		s = setTimeout('scrollDown()', 10);
		document.getElementById('previousSpan').className = "on";
	}
	else
	{
		document.getElementById('moreSpan').className = "";
	}
}

function scrollWheelUp()
{
	if(screenTop < 0)
	{
		screenTop = screenTop + scrollSpeed;
		document.getElementById('screen').style.top = screenTop + "px";
		document.getElementById('moreSpan').className = "on";
	}
	else
	{
		document.getElementById('previousSpan').className = "";
	}
}

function scrollWheelDown()
{
	if(screenTop > document.getElementById('subBody').offsetHeight - document.getElementById('screen').offsetHeight)
	{
		screenTop = screenTop - scrollSpeed;
		document.getElementById('screen').style.top = screenTop + "px";
		document.getElementById('previousSpan').className = "on";
	}
	else
	{
		document.getElementById('moreSpan').className = "";
	}
}

function scrollVideoUp()
{
	if(screenTop < 0)
	{
		screenTop = screenTop + 245;
		document.getElementById('screen').style.top = screenTop + "px";
	}
	resetSliderButtons();
}

function scrollVideoDown()
{
	if(screenTop > document.getElementById('subBody').offsetHeight - document.getElementById('screen').offsetHeight)
	{
		screenTop = screenTop - 245;
		document.getElementById('screen').style.top = screenTop + "px";
	}
	resetSliderButtons();
}

function scrollStop()
{
	clearTimeout(s);
}


function changeTab(tab)
{
	document.getElementById('subTab-'+subTab).className = "";
	document.getElementById('subTabDiv-'+subTab).className = "hide";
	document.getElementById('subTab-'+tab).className = "selected";
	document.getElementById('subTabDiv-'+tab).className = "show";
	subTab = tab;
	
	resetSlider();
}

function changeTab2(tab)
{
	document.getElementById('subTab-'+subTab2).className = "";
	document.getElementById('subTabDiv-'+subTab2).className = "hide";
	document.getElementById('subTab-'+tab).className = "selected";
	document.getElementById('subTabDiv-'+tab).className = "show";
	subTab2 = tab;
	
	resetSlider();
}

function resetSlider()
{
	document.getElementById('screen').style.top = 0;
	screenTop = 0;
	resetSliderButtons();
}

function resetSliderButtons()
{
	if(screenTop < 0)
	{
		document.getElementById('previousSpan').className = "on";
	}
	else
	{
		document.getElementById('previousSpan').className = "";
	}
	if(screenTop > document.getElementById('subBody').offsetHeight - document.getElementById('screen').offsetHeight)
	{
		document.getElementById('moreSpan').className = "on";
	}
	else
	{
		document.getElementById('moreSpan').className = "";
	}
}

function togglePL()
{
	if(document.getElementById('PL-Listing').className == "show")
	{
		document.getElementById('PL-Listing').className = "hide";
		document.getElementById('PL-MoreInfo').className = "show";
		document.getElementById('PLmoreAnchor').innerHTML = "Back to Point Leader Track Listing";
		document.getElementById('PLToggleDiv').className = "hide";
		document.getElementById('subBody').className = "tallHeight";
	}
	else
	{
		document.getElementById('PL-Listing').className = "show";
		document.getElementById('PL-MoreInfo').className = "hide";
		document.getElementById('PLmoreAnchor').innerHTML = "Find out more about Point Leader Breakouts";
		document.getElementById('PLToggleDiv').className = "show";
		document.getElementById('subBody').className = "changeHeight";
	}
    resetSlider();
}

function getQueryVariable(variable) { 
	var query = window.location.search.substring(1); 
	var vars = query.split("&"); 
	for (var i=0;i<vars.length;i++) { 
		var pair = vars[i].split("="); 
		if (pair[0] == variable) { 
			return pair[1]; 
		} 
	} 

}

function breakoutPDF(track)
{
    document.getElementById('pdf').innerHTML = pdfTracks[track];   
}

/** This is high-level function; REPLACE IT WITH YOUR CODE.
 * It must react to delta being more/less than zero.
 */
function handle(delta) {
	if (delta < 0)
	{
	    if(videos == true)
	        scrollVideoDown();
	    else
		    scrollWheelDown();
	}
	else
    {
        if(videos == true)
            scrollVideoUp();
        else
		    scrollWheelUp();
	}
}

function wheel(event){
	var delta = 0;
	if (!event) event = window.event;
	if (event.wheelDelta) {
		delta = event.wheelDelta/120; 
		if (window.opera) delta = -delta;
	} else if (event.detail) {
		delta = -event.detail/3;
	}
	if (delta)
		handle(delta);
        if (event.preventDefault)
                event.preventDefault();
        event.returnValue = false;
}