// JavaScript Document
var pages = { pageWidth: 565, 
	curPage : 1, 
	maxPages : 5,
	startMargin : 0,
	curMargin : 0,
	targetMargin : 0,
	targetPage : 0,
	growing : false,
	animation : false,
	animationId : 0,
	baseStep : 50,
	step : 50,
	
	move : function() {
		var wrapper = document.getElementById('contentWrapperInner');
		
		if (pages.growing) {
			if (pages.curMargin - pages.step <= pages.targetMargin) {
				wrapper.style.marginLeft = pages.targetMargin + 'px';
			
				clearInterval(pages.animationId);
				pages.curPage = pages.targetPage
				pages.animation = false;
				pages.step = pages.baseStep;
			}
			else {
				pages.curMargin -= pages.step;
				
				var delta = Math.abs(pages.targetMargin - pages.startMargin);
				var curStep = Math.abs(pages.curMargin - pages.startMargin);
				if (curStep < (delta /2) ) {
					pages.step += 50;
				}
				else {
					if (pages.step > 50)
						pages.step -= 50;
				}
				wrapper.style.marginLeft = pages.curMargin + 'px';	
			}
		}
		else {
			if (pages.curMargin + pages.step >= pages.targetMargin) {
				wrapper.style.marginLeft = pages.targetMargin + 'px';
			
				clearInterval(pages.animationId);
				pages.curPage = pages.targetPage
				pages.animation = false;
				pages.step = pages.baseStep;
			}
			else {
				pages.curMargin += pages.step;
				
				var delta = Math.abs(pages.targetMargin - pages.startMargin);
				var curStep = Math.abs(pages.curMargin - pages.startMargin);
				if (curStep < (delta /2) ) {
					pages.step += 50;
				}
				else {
					if (pages.step > 50)
						pages.step -= 50;
				}
				wrapper.style.marginLeft = pages.curMargin + 'px';	
			}
		}
	}
};

function gotoPage(ndx) {
	var wrapper = document.getElementById('contentWrapperInner');
	
	if (ndx > 0 && ndx <= pages.maxPages) {
		if (!pages.animation) {
			if (ndx > pages.curPage)
				pages.growing = true;
			else
				pages.growing = false;
			
			pages.targetPage = ndx;
			pages.startMargin = pages.curMargin;
			pages.targetMargin = (0 - ((ndx-1) * pages.pageWidth));
			pages.animationId = setInterval('pages.move()', 50);
			pages.step = pages.baseStep;
			pages.animation = true;
		}
		//wrapper.style.marginLeft = (0 - ((ndx-1) * pages.pageWidth)).toString() + 'px';
	}
}