// JavaScript Document
$(function (){

   easyslider(); 
 
});


function tween(position, listwidth){
	$('.easyslider_content').animate({"left": ""+position+"px"}, "slow", function() {
    // Animation complete.
	pos=get_position(listwidth);
	check_buttons(pos);
  });
}

function check_buttons(pos){
		
	pos['current'] == pos['last'] ? disable_btn('next'):enable_btn('next');
	pos['current'] == 0 ? disable_btn('previous'):enable_btn('previous');
	
}

function disable_btn(name){
	btn = '.easyslider_'+name;
	$(btn).css({'display': 'none'});
}

function enable_btn(name){
	btn = '.easyslider_'+name;
	$(btn).css({'display': 'block'});
}

function get_position(listwidth){
	container_width = parseInt($('.easyslider_container').width());
	
	pos = new Array();
	pos['current'] = parseInt($('.easyslider_content').css('left'));
	pos['last'] = -(listwidth-container_width);
	pos['next'] = pos['current']-container_width;
	pos['pre'] = pos['current']+container_width;
	  
	if (pos['next'] < pos['last']){
		pos['next'] = pos['last'];
	}
	  	 
	if (pos['pre']>0){
		pos['pre'] = 0;
	}
	//alert(pos['next']);
	return pos;
}
function list_size(items){
	var itemwidth = 130 + 5 + 5 + 0 + 0; // width + marginleft + marginrigth + borderleft + borderright
	var count = items.length;
	var listwidth = count*itemwidth;
	return listwidth;
}

function easyslider(){
	$('.easyslider').wrapInner('<div class="easyslider_container"><div class="easyslider_content"></div></div>');
	$('.easyslider_content').css({left: '0px', position: 'relative'});
	$('.easyslider').append('<div class="easyslider_next"></div><div class="easyslider_previous"></div>');
	  
	var items = $('.easyslider').find('.easyslider_item');
	listwidth = list_size(items);
	$('.easyslider_content').css({width: listwidth + 'px'});
	  
	pos = get_position(listwidth);
	check_buttons(pos);
	
	$('.easyslider_next').click(function(){
	 	
		pos = get_position(listwidth);
		tween(pos['next'], listwidth);
		return false;
    });
	
	$('.easyslider_previous').click(function(){
		
		pos = get_position(listwidth, listwidth);
		tween(pos['pre']);
		return false;
    });
  
}