jQuery.fn.allWidth = function(){

    var allWidth = 0;

    this.each(function(){
        allWidth += $(this).outerWidth(true);
    });

    return allWidth;
}
jQuery.fn.slider = function(options){

        var settings = jQuery.extend({}, options);

        var $prev = $(settings.prev);
        var $prevs = $(settings.prevs);
        var $next = $(settings.next);
        var $nexts = $(settings.nexts);
        var $items = $(settings.item);
        var $container = $(settings.container);
        var $slider = $(settings.slider);

        if($items.length <= 3){
            $prevs.show();
            $nexts.show();
        }
        $prev.click(function(){
            $(this).blur();

            if( $items.filter('.slided').length > 0 )
            {
                var $invisible_items = $items.filter('.slided');
                var count_invisible_items = $invisible_items.length;
                var $last_invisible_item = $invisible_items.eq( count_invisible_items - 1 ).removeClass('slided');
                var item_Width = $last_invisible_item.outerWidth(true);
                $slider.animate({ marginLeft : '+='+item_Width+'px' });
                
                if( $items.filter('.slided').length == 0 ){
                    $prev.hide();
                    $prevs.show();
                }
                if($items.filter('.slided').length >= 0){
                    $next.show();
                    $nexts.hide();
                }
            }

            return false;
        });
        
        $next.click(function(){
            $(this).blur();

            if( $items.filter('*:not(.slided)').allWidth() > $container.outerWidth(true) )
            {
                var $first_visible_item = $items.filter('*:not(.slided)').eq(0).addClass('slided');
                var item_Width = $first_visible_item.outerWidth(true);
                $slider.animate({ marginLeft : '-='+item_Width+'px' });

                if( $items.filter('*:not(.slided)').allWidth() < ($container.outerWidth(true)+30) ){
                    $next.hide();
                    $nexts.show();
                }
                if($items.filter('.slided').length > 0){
                    $prev.show();
                    $prevs.hide();
                }
            }
            return false;
        });

        $(window).resize(function(){
            $slider.css({ marginLeft : '0px' });
            $items.removeClass("slided");
            $prev.hide();
            $prevs.show();
            $next.show();
            $nexts.hide();
        });
};