var vssMustDieStories = [ 'ann', 'jen', 'mike', 'sally', 'stu', 'xiao' ];

var stickyStory = false;

var killAllBut = function(leaveit) {
    for (var i = 0; i < vssMustDieStories.length; ++i)
    {
	var storyname = vssMustDieStories[i];
	if (storyname != leaveit.id)
	{
	    var subtext = storyname + 'subtext';

	    if ($(storyname).visible())
	    {
			Effect.Fade(storyname, { duration: 0.25 });
	    }

	    var img = $$('#' + storyname + 'link a img')[0];
	    img.src = 'images/' + storyname + '_off.jpg';

	    $(subtext).hide();
	}
    }
};


function showStory(story)
{
    killAllBut(story);
    Effect.Appear(story, { queue: 'end', duration: 0.5 });

    var img = $$('#' + story.id + 'link a img')[0];
    img.src = 'images/' + story.id + '_on.jpg';

    var subtext = story.id + 'subtext';
    $(subtext).show();
}

function addStoryHandler(link, linkdiv, story) {
    link.observe('mouseover', 
		 function(e) {
		     if (! stickyStory)
		     {
			 showStory(story);
		     }
		 }
		);

    link.observe('click',
		 function(e) {
		     showStory(story);
		     stickyStory = true;
		     Event.stop(e);
		 }
		);
}    

function addStoryHandlers() {

    for (var i = 0; i < vssMustDieStories.length; ++i)
    {
	var story = vssMustDieStories[i];
	var linkname = story + 'link';
	var storydiv = $(story);
	var linkdiv = $(linkname);
	var link = $$('#' + linkname + ' a')[0];

	addStoryHandler(link, linkdiv, storydiv);
    }
}

// Returns the version of Internet Explorer or a -1
// (indicating the use of another browser).
function getInternetExplorerVersion()
{
    var rv = -1; // Return value assumes failure.

    if (navigator.appName == 'Microsoft Internet Explorer')
    {
	var ua = navigator.userAgent;
	var re  = new RegExp("MSIE ([0-9]{1,}[\.0-9]{0,})");
	if (re.exec(ua) != null)
	    rv = parseFloat( RegExp.$1 );
    }

    return rv;
}


function trackExit(how, fromwhere)
{
	if (typeof(pageTracker) != 'undefined')
	{
		pageTracker._trackEvent('Exit', how, fromwhere);
	}
}

if ((getInternetExplorerVersion() > 0) && (getInternetExplorerVersion() < 6))
{
    for (var i = 0; i < vssMustDieStories.length; ++i)
    {
	$(vssMustDieStories[i]).show();
	$(vssMustDieStories[i] + 'subtext').show();
    }
}
else
{
    addStoryHandlers();
    showStory($('sally'));
}