//depends on scrollTo plugin

var zoom_active = true;
$(document).ready(
	function() {
		//do not zoom when user is navigating slides 
		$(".nozoom").hover(
			function() {
				zoom_active = false;
			}, function () {
				zoom_active = true;
			});
		
				
		//set up zoom behavior
		$("#slide")
			.css("cursor", "pointer")
			.click(function (e) {
				var presentation_id;
				var slideFile;
				var zoomSrc;
				var offset;
				var slideSrc;
				var slideHeight = 0;
				var slideSrcPieces = [];
				var zoomSlideHeight = 0;
				var zoomSlideWidth = 650; //auto scaled to this width
				var windowLeftOffset = 0;
				
				//proceed or not
				if (zoom_active != true) {
					return;
				}
				
				//detemine where to place the zoomed image
				windowLeftOffset = (($(window).width() - zoomSlideWidth) / 2);
				if (windowLeftOffset <  0) {
					windowLeftOffset = 20;
				}

				//get position of the title and scroll to the title
				var slide_zoom_anchor = $('#slide_zoom_anchor').val();
				offset = $("#" + slide_zoom_anchor).offset();
				
				//set zoom slide height
				slideHeight = $('#slide').height();
				if (slideHeight == 0) {
					return;
				}
				zoomSlideHeight = zoomSlideWidth * (slideHeight / $('#slide').width());
				
				//determine current slide source
				slideSrc = $('#slide').css('backgroundImage');
				slideSrc = slideSrc.replace(/http:\/\/|url\(|\)/gi, '');
				
				//set full size slide src
				slideSrcPieces = slideSrc.split('/');
				presentation_id = slideSrcPieces[2];
				slideFile = slideSrcPieces[5];
				zoomSrc = 'http://framewelder.com-cache.s3.amazonaws.com/presentations/' + presentation_id + '/slides/full/' + slideFile;

				//add zoom div to page
				$('body').prepend('<div id="zoom"></div>');
				
				//style the zoom div
				$('#zoom')
					.css({
						position: 'absolute',
						zIndex: 5001,
						height: zoomSlideHeight + 'px',
						width: zoomSlideWidth + 'px',
						top: offset['top'],
						left: windowLeftOffset + 'px',
						cursor: 'pointer',
						backgroundRepeat: 'no-repeat',
						backgroundImage: 'url(' + zoomSrc + ')'
					})
					.click(function (e) {
						$("#zoom").remove();
					});
			});
});