function scrollerPhotos(params) {

//     params = {
//        id:'id' ==> id скроллера,
//        slideLeftOnLoad:true ==> выезд элементов слева при загрузке
//    }

    var shift = 0;        
    var photos_vis // целое видимое кол-во превьюшек
    var photo_clip; // величина обреза видимой областью фото справа или слева    
    var photos_container = $("#" + params.id);
    var photos_inner = photos_container.find("> div.scroll_content");
    var avail_width = photos_inner.outerWidth(true);
    var photos_ul = photos_inner.find("> div.products");
    var lis = photos_ul.find("> div").length; // всего товаров в списке    
    var prev_scroll_btn = photos_container.find("> span.scroll_right");
    var next_scroll_btn = photos_container.find("> span.scroll_left");
    var scroll_speed = 700;

    var one_li_w = photos_ul.find("> div").outerWidth(this); //ширина li
    var ext_l = 0; // колво невидимых продуктов слева
    var ext_r = lis - Math.floor(avail_width / one_li_w); // колво невидимых продуктов справа
    var edge_r = false; // flag, если список дошел до правого края
    
    photos_inner.width(avail_width)
    // для отбражения товаров в одну строку задаем ширину списку
    photos_ul.width(lis * one_li_w);
   
    // проверяем кол-во переданных параметров
    if(params.slideLeftOnLoad) {
        // slideLeftOnLoad:true ==> выезд элементов слева при загрузке
        photos_ul.css("marginLeft", -photos_ul.width() + "px");
        var timeout_slideOnLoad = setTimeout(function() {slideOnLoad()}, 700)
        function slideOnLoad() {
            photos_ul.animate({"marginLeft":0}, 1000);
            clearTimeout(timeout_slideOnLoad);
        }
    }
    
    //photos_vis = lis - ext_r;
    photos_vis = parseInt(avail_width / one_li_w, 10);
    //photo_clip = photos_vis * one_li_w + one_li_w - avail_width;
    photo_clip = avail_width - (photos_vis * one_li_w);    
    
    if (avail_width >= photos_ul.width()) {
        next_scroll_btn.hide();
        prev_scroll_btn.hide();
    }
    // стрелка слева
    next_scroll_btn.click(function () {
        prev_scroll_btn.removeClass("inactive");
        //photo_clip = avail_width - (photos_vis * one_li_w);
        if(ext_r == 0) edge_r = true;
        if (!($(this).hasClass("inactive"))) {
            
            if(ext_l > photos_vis) {
                shift = photos_vis * one_li_w;
                //console.log("l1a / " + shift + " / photos_vis = " + photos_vis + " / photo_clip = " + photo_clip + " / ext_l = " + ext_l + " / ext_r = " + ext_r)
                ext_l -= photos_vis;  
                ext_r += photos_vis;
                //photo_clip = avail_width - (photos_vis * one_li_w); 
                //console.log(shift + " - left a2 || ext_l > photos_vis / ext_l = " + ext_l + " / ext_r = " + ext_r);
            }
            else if(ext_l <= photos_vis ) {
                $(this).addClass("inactive");
                shift = ext_l * one_li_w;
                
                if(ext_l == 1) {
                    shift = photo_clip;
                }
                //console.log(shift + " - left b1  || ext_l <= photos_vis / ext_l = " + ext_l + " / ext_r = " + ext_r);
                ext_l = 0;
                ext_r = lis - photos_vis;
                
                //console.log("l1b / " + shift + " / photos_vis = " + photos_vis + " / photo_clip = " + photo_clip + " / ext_l = " + ext_l + " / ext_r = " + ext_r)
                
            }
            if(ext_l == 0)
                photos_ul.stop(false, true).animate({ "marginLeft": "0" }, scroll_speed);
            else 
                photos_ul.stop(false, true).animate({ "marginLeft": "+=" + shift + "px" }, scroll_speed);
        }
    })
    // стрелка справа
    prev_scroll_btn.click(function () {
        next_scroll_btn.removeClass("inactive");
        if (!($(this).hasClass("inactive"))) {
            
            if(ext_r > photos_vis) {
                //photo_clip = avail_width - (photos_vis * one_li_w);
                shift = photos_vis * one_li_w;
                //console.log("r1a / " + shift + " / photos_vis = " + photos_vis + " / photo_clip = " + photo_clip + " / ext_l = " + ext_l + " / ext_r = " + ext_r)
                ext_r -= photos_vis;
                ext_l += photos_vis;
                //console.log("r1a / " + shift + " / photos_vis = " + photos_vis + " / photo_clip = " + photo_clip + " / ext_l = " + ext_l + " / ext_r = " + ext_r)
                
            }
            else if(ext_r <= photos_vis) {
                $(this).addClass("inactive");
                
                //photo_clip = avail_width - (photos_vis * one_li_w); 
                if(ext_r > 1) {
                    //photo_clip = 0;
                    
                    shift = ext_r * one_li_w - photo_clip;
                    if(edge_r && ext_l != 0) {
                        shift = ext_r * one_li_w;
                        //console.log("edge_r")
                    }
                    //console.log("r1b / " + shift + " / photos_vis = " + photos_vis + " / photo_clip = " + photo_clip + " / ext_l = " + ext_l + " / ext_r = " + ext_r)
                    edge_r = false;
                }
                
                else if(ext_r <= 1) {                    
                    shift = (one_li_w - photo_clip);
                    //console.log("r1c / " + shift + " / photos_vis = " + photos_vis + " / photo_clip = " + photo_clip + " / ext_l = " + ext_l + " / ext_r = " + ext_r)
                }
                //console.log(shift + " - right b1 || ext_r <= photos_vis / ext_l = " + ext_l + " / ext_r = " + ext_r)
                ext_r = 0;
                ext_l = lis - photos_vis;
                
                //console.log("r2 / " + shift + " / photos_vis = " + photos_vis + " / photo_clip = " + photo_clip + " / ext_l = " + ext_l + " / ext_r = " + ext_r)
            }
//            if(ext_r == 0) 
//                photos_ul.stop(false, true).animate({ "marginLeft": (photos_ul.width - avail_width + photo_clip) + "px" }, scroll_speed);
//            else 
                photos_ul.stop(false, true).animate({ "marginLeft": "-=" + shift + "px" }, scroll_speed);   
        }
    })

}  // /scrollerPhotos


// -------------html
//<div class="blockProducts-abs section-abs blockProducts-onMain" id="sp1">
//    <div class="inner">
//        <ul class="clearfix">
//            <li>
//                ...
//            </li>
//        </ul>
//    </div>
//    <div class="arrnav prev"></div>
//    <div class="arrnav next inactive"></div>
//</div>        

// -------------css
//.blockProducts-abs {
//    position: relative;
//}
//.blockProducts-abs .inner {
//    overflow: hidden;
//    position: relative;
//}
//.blockProducts-abs li {
//    float: left;
//    margin: 0;
//    position: relative;
//    width: 146px;
//}

// -------------в конце indexa
//<script type="text/javascript" src="/js/slider.js"></script>
//<script type="text/javascript">
//      $(document).ready(function () {
//          scrollerPhotos('sp1');
//          scrollerPhotos('sp2');
//      });
//</script>