scroll.js

!function(t,e){"function"==typeof define&&define.amd?define([],e()):"object"==typeof module&&module.exports?module.exports=e():function n(){document&&document.body?t.zenscroll=e():setTimeout(n,9)}()}(this,function(){"use strict";var t=function(t){return"getComputedStyle"in window&&"smooth"===window.getComputedStyle(t)["scroll-behavior"]};if("undefined"==typeof window||!("document"in window))return{};var e=function(e,n,o){n=n||999,o||0===o||(o=9);var i,r=function(t){i=t},u=function(){clearTimeout(i),r(0)},c=function(t){return Math.max(0,e.getTopOf(t)-o)},f=function(o,i,c){if(u(),0===i||i&&i<0||t(e.body))e.toY(o),c&&c();else{var f=e.getY(),a=Math.max(0,o)-f,l=(new Date).getTime();i=i||Math.min(Math.abs(a),n),function t(){r(setTimeout(function(){var n=Math.min(1,((new Date).getTime()-l)/i),o=Math.max(0,Math.floor(f+a*(n<.5?2*n*n:n*(4-2*n)-1)));e.toY(o),n<1&&e.getHeight()+o<e.body.scrollHeight?t():(setTimeout(u,99),c&&c())},9))}()}},a=function(t,e,n){f(c(t),e,n)},l=function(t,n,i){var r=t.getBoundingClientRect().height,u=e.getTopOf(t)+r,l=e.getHeight(),s=e.getY(),d=s+l;c(t)<s||r+o>l?a(t,n,i):u+o>d?f(u-l+o,n,i):i&&i()},s=function(t,n,o,i){f(Math.max(0,e.getTopOf(t)-e.getHeight()/2+(o||t.getBoundingClientRect().height/2)),n,i)};return{setup:function(t,e){return(0===t||t)&&(n=t),(0===e||e)&&(o=e),{defaultDuration:n,edgeOffset:o}},to:a,toY:f,intoView:l,center:s,stop:u,moving:function(){return!!i},getY:e.getY,getTopOf:e.getTopOf}},n=document.documentElement,o=function(){return window.scrollY||n.scrollTop},i=e({body:document.scrollingElement||document.body,toY:function(t){window.scrollTo(0,t)},getY:o,getHeight:function(){return window.innerHeight||n.clientHeight},getTopOf:function(t){return t.getBoundingClientRect().top+o()-n.offsetTop}});if(i.createScroller=function(t,o,i){return e({body:t,toY:function(e){t.scrollTop=e},getY:function(){return t.scrollTop},getHeight:function(){return Math.min(t.clientHeight,window.innerHeight||n.clientHeight)},getTopOf:function(t){return t.offsetTop}},o,i)},"addEventListener"in window&&!window.noZensmooth&&!t(document.body)){var r="scrollRestoration"in history;r&&(history.scrollRestoration="auto"),window.addEventListener("load",function(){r&&(setTimeout(function(){history.scrollRestoration="manual"},9),window.addEventListener("popstate",function(t){t.state&&"zenscrollY"in t.state&&i.toY(t.state.zenscrollY)},!1)),window.location.hash&&setTimeout(function(){var t=i.setup().edgeOffset;if(t){var e=document.getElementById(window.location.href.split("#")[1]);if(e){var n=Math.max(0,i.getTopOf(e)-t),o=i.getY()-n;0<=o&&o<9&&window.scrollTo(0,n)}}},9)},!1);var u=new RegExp("(^|\\s)noZensmooth(\\s|$)");window.addEventListener("click",function(t){for(var e=t.target;e&&"A"!==e.tagName;)e=e.parentNode;if(!(!e||1!==t.which||t.shiftKey||t.metaKey||t.ctrlKey||t.altKey)){if(r)try{history.replaceState({zenscrollY:i.getY()},"")}catch(t){}var n=e.getAttribute("href")||"";if(0===n.indexOf("#")&&!u.test(e.className)){var o=0,c=document.getElementById(n.substring(1));if("#"!==n){if(!c)return;o=i.getTopOf(c)}t.preventDefault();var f=function(){window.location=n},a=i.setup().edgeOffset;a&&(o=Math.max(0,o-a),f=function(){history.pushState(null,"",n)}),i.toY(o,null,f)}}},!1)}return i});