автопрокрутка контента как в соцсетях

var icms=icms||{};
icms.pageautoload=function(a){this.options={MAIN_CONTAINER:"article",BOTTOM_MARGIN:150,NEXT_BTN_CAPTION:"\u0421\u043b\u0435\u0434\u0443\u044e\u0449\u0430\u044f",LOADING_CAPTION:"\u0417\u0430\u0433\u0440\u0443\u0437\u043a\u0430...",SCROLL_SPEED:1100,PAGE_ADD_SPEED:600,PAGEBAR_CSS:{position:"fixed","z-index":"999999",padding:"15px",margin:"0","background-color":"rgba(255, 255, 255, 0.9)",border:"1px solid #DDDDDD"},CONTAINERS:".content_list .activity-list #comments_list .groups-list #album-photos-list #search_results_list #users_profiles_list #users_karma_log_list #entries_list".split(" ")};var k=
!1,f,n,g;this.onDocumentReady=function(){if(History.enabled){icms.pageautoload.options.CONTAINERS.forEach(function(c){0<a(c).length&&(g=c)});var b=a(".pagebar");if(0< !b.length)return!1;a(".pagebar_notice",b).remove();var c=a(icms.pageautoload.options.MAIN_CONTAINER);c.append("<div class='loading' style='display: none; margin-top: 10px;'>"+icms.pageautoload.options.LOADING_CAPTION+"</div>");c.append("<div id='pagebar_data' style='display: none;'/>");var d=parseInt(a(".pagebar .pagebar_current").text(),
10),h=a("#pagebar_data"),e=[];e[d-1]=b[0].outerHTML;h.data("pageArray",[d]).data("pageBar",e);a(g).prepend("<div id='page_anchor_"+d+"' style='display: none;'>"+d+"</div>");var p=a(window).height(),m=c.offset().top+42;f=m;a(window).scroll(function(){var b=a(this).scrollTop();b+10<m?f=m-b:f=10;var d=[];a("div[id ^= 'page_anchor_']").each(function(b){d.push(a(this).next().offset().top)});for(var g=c.height(),l=0,e=h.data("pageArray")[0],l=0;l<d.length;l++)0!=l&&b>=d[l]-p/2&&e++;l=p+b;g-l<icms.pageautoload.options.BOTTOM_MARGIN&&
(e=h.data("pageArray")[0]+d.length-1,k||(k=!0,b=a(".pagebar .pagebar_current").next().attr("href"),icms.pageautoload.getPage(b)));k||(b=a(".pagebar a:contains("+e+")").attr("href"),History.pushState({},null,b),icms.pageautoload.getPagebar(e))});a(window).resize(function(){n=a(document).width()-c.outerWidth()-c.offset().left+10;icms.pageautoload.setCSS()});a(window).resize()}};this.getPage=function(b){if(void 0==b)return k=!1;var c=a(".pagebar .pagebar_current").next().text();if(c===a(".pagebar #a_next_btn").text())return k=
!1;var d=parseInt(c,10),h=a("#pagebar_data");if(-1!==a.inArray(d,h.data("pageArray")))return k=!1;var e=icms.pageautoload.options.MAIN_CONTAINER+" .loading";a(e).show();a.ajax({url:b,type:"POST",dataType:"html",success:function(b){a(g).append("<div id='page_anchor_"+d+"' style='display: none;'>"+d+"</div>");var c=h.data("pageArray");c.push(d);h.data("pageArray",c);var f;a(b).is(g)?f=a(b):f=a(b).find(g).parent().children();f.filter(g).children().appendTo(a(g)).hide().fadeIn(icms.pageautoload.options.PAGE_ADD_SPEED);
a(e).show();f.filter(".pagebar").replaceAll(a(".pagebar"));a(".pagebar > .pagebar_notice").remove();b=h.data("pageBar");b[d-1]=a(".pagebar")[0].outerHTML;h.data("pageBar",b);icms.pageautoload.getPagebar(d-1);a(e).hide();k=!1}})};this.setPagebarLinks=function(){a(".pagebar a").each(function(b){b=a(this).attr("href");var c=b.indexOf("?page="),c=-1!==c?parseInt(b.substr(c+6),10):1;-1!==a.inArray(c,a("#pagebar_data").data("pageArray"))&&(a(this).attr("name","#page_anchor_"+c),a(this).addClass("onPageNow"),
isNaN(parseInt(a(this).text(),10))&&a(this).attr("id","a_back_btn"));a(this).text().toUpperCase()===icms.pageautoload.options.NEXT_BTN_CAPTION.toUpperCase()&&a(this).attr("id","a_next_btn")})};this.getPagebar=function(b){var c=a("#pagebar_data").data("pageBar");a(".pagebar").replaceWith(c[b-1]);icms.pageautoload.setPagebarLinks();icms.pageautoload.setAllClick();icms.pageautoload.setCSS()};this.setAllClick=function(){icms.pageautoload.setClick(a(".pagebar a.onPageNow"))};this.setClick=function(b){b.click(function(){var b=
a(this.name).next().offset().top;a("html,body").stop().animate({scrollTop:b},icms.pageautoload.options.SCROLL_SPEED).animate({scrollTop:b-20},icms.pageautoload.options.SCROLL_SPEED);return!1})};this.setCSS=function(){var b=a(".pagebar");b.css(icms.pageautoload.options.PAGEBAR_CSS);b.css("top",f);b.css("right",n)};return this}.call(icms.pageautoload||{},jQuery);