var prevBlock=0, curBlock=1, nBlocks=4;
var tabpref="#istab",conpref="#iStoryTabCon",pxMove=825;

jQuery(document).ready(function(){
    setupIS(1,true);								
	jQuery("#isNext").click(function(){
		if(curBlock>=nBlocks)
			curBlock=1;
		else
			curBlock++;
		setupIS(curBlock);
	});
	jQuery("#isPrev").click(function(){
		prevBlock = curBlock;
		if(curBlock<=1)
			curBlock=4;
		else
			curBlock--;
		setupIS(curBlock);
	});
});

function setupIS(xBlock,topTrue)
{
	if(prevBlock>0 && prevBlock!=xBlock)
	{
		jQuery(conpref+prevBlock).animate({left:"-"+pxMove+"px"},500,setupISClear);
	}
	if(topTrue){
		jQuery(conpref+xBlock).animate({top:"0px"},500);
	}
	else{
		jQuery(conpref+xBlock).animate({left:"0px"},500);
	}
	for(i=1;i<=nBlocks;i++)
	{
		if(i==xBlock){
			jQuery(tabpref+i).attr("class","iStoryBlkMidTabOn")
		}
		else if(prevBlock!=xBlock){		
			jQuery(tabpref+i).attr("class","iStoryBlkMidTabOff")
		}
	}
	
	prevBlock=xBlock;
	curBlock=xBlock;
}

function setupISClear()
{
	for(i=1;i<=nBlocks;i++)
	{
		if(i!=curBlock){
			jQuery(conpref+i).css("left","825px");
		}
	}	
}