// page load
	var vid = varcall('v');
	var sharelink = '';

function grabbit(pl) {
	/*====
			on page load check to see if a vid has been called
			if it has been, check to make sure the vid exists and if it does exist, substitute the first video for the vid that has been called
	==== */
	vid = setvid(pl);	// figure out which video ID to show
	
	turnvideobuttonsoff();	// turn off all the other video buttons
	turnvideobuttonon(vid);	// turn on the correct video button
	videosynopsis(vid);		// turn on correct synopsis
	sharelink = pathname() + '?v=' + vid;	// place correct share link
	document.getElementById('shl').value = sharelink;
	buildembedcode(vid);	// place correct embed code
	if (vidimg != vid) {
		document.getElementById('video_player_yes').style.display = 'block';
		if (document.getElementById('video-replace-' + vidimg)) {
			document.getElementById('video-replace-' + vidimg).style.display = 'none';
		}
		setTimeout('player.playByChoice(' + vid + ');', 300);
	} else {
		
		if (document.getElementById('video-replace-' + vidimg)) {
			document.getElementById('video-replace-' + vidimg).style.display = 'block';
		}
		setTimeout('player.playByChoice(' + vid + ');', 300);
		document.getElementById('video_player_yes').style.display = 'none';
		
	}
	
	
}

function buildembedcode(xl) {
	var pl = "<iframe style='width: 525px; height: 345px; padding: 0; margin: 0;' id='embastd' src='http://www.microsoft.com/uk/academia/studenttechnologyday/VideoPlayer.html?v=" + xl + "'/>";
	document.getElementById('shel').value = pl;
	
}
function videosynopsis(pl) {
	for (i = 1; i <= vididc; i++) {	// turn off synopsis
		if (vidid[i] != pl) {
			if (document.getElementById('synopsis-' + vidid[i])) {
				document.getElementById('synopsis-' + vidid[i]).style.display = 'none';
			}
		}
	}
	if (document.getElementById('synopsis-' + pl)) {	 // turn on the correct synopsis
		document.getElementById('synopsis-' + pl).style.display = 'block';
	}
}
function setvid(xl) {
	var pl = '';
	if (xl == '') {
		xl = vididf;
	}
	// make sure the video ID exists
	for (i = 1; i <= vididc; i++) {
		if (xl == vidid[i]) {
			pl = true;
			break;
		} else {
			pl = false;
		}
	}
	if (pl != true) {
		xl = vididf;
	}
	return xl;
}

function turnvideobuttonon(id) {
	if (document.getElementById('video_tab_' + id)) {
		document.getElementById('video_tab_' + id).className = 'video_tab_selected';
	}
}
function turnvideobuttonsoff() {
	for (i = 1; i <= vididc; i++) {
		if (document.getElementById('video_tab_' + vidid[i])) {
			document.getElementById('video_tab_' + vidid[i]).className = 'video_tab';
		}
	}
}

function varcall( name ) {
	name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");
	var regexS = "[\\?&]"+name+"=([^&#]*)";
	var regex = new RegExp( regexS );
	var results = regex.exec( window.location.href );
	if( results == null ) {
		return "";
	} else {
		return results[1];
	}
}

function pathname() {
	var results = window.location.href.split('?');
	return results[0]
}