var VirtualScroll=(function(document){var vs={};var numListeners,listeners=[],initialized=!1;var touchStartX,touchStartY;var touchMult=2;var firefoxMult=15;var keyStep=120;var mouseMult=1;var bodyTouchAction;var hasWheelEvent='onwheel' in document;var hasMouseWheelEvent='onmousewheel' in document;var hasTouch='ontouchstart' in document;var hasTouchWin=navigator.msMaxTouchPoints&&navigator.msMaxTouchPoints>1;var hasPointer=!!window.navigator.msPointerEnabled;var hasKeyDown='onkeydown' in document;var isFirefox=navigator.userAgent.indexOf('Firefox')>-1;var event={y:0,x:0,deltaX:0,deltaY:0,originalEvent:null};vs.on=function(f){if(!initialized)initListeners();listeners.push(f);numListeners=listeners.length}
vs.options=function(opt){keyStep=opt.keyStep||120;firefoxMult=opt.firefoxMult||15;touchMult=opt.touchMult||2;mouseMult=opt.mouseMult||1}
vs.off=function(f){listeners.splice(f,1);numListeners=listeners.length;if(numListeners<=0)destroyListeners()}
var notify=function(e){event.x+=event.deltaX;event.y+=event.deltaY;event.originalEvent=e;for(var i=0;i<numListeners;i++){listeners[i](event)}}
var onWheel=function(e){event.deltaX=e.wheelDeltaX||e.deltaX*-1;event.deltaY=e.wheelDeltaY||e.deltaY*-1;if(isFirefox&&e.deltaMode==1){event.deltaX*=firefoxMult;event.deltaY*=firefoxMult}
event.deltaX*=mouseMult;event.deltaY*=mouseMult;notify(e)}
var onMouseWheel=function(e){event.deltaX=(e.wheelDeltaX)?e.wheelDeltaX:0;event.deltaY=(e.wheelDeltaY)?e.wheelDeltaY:e.wheelDelta;notify(e)}
var onTouchStart=function(e){var t=(e.targetTouches)?e.targetTouches[0]:e;touchStartX=t.pageX;touchStartY=t.pageY}
var onTouchMove=function(e){var t=(e.targetTouches)?e.targetTouches[0]:e;event.deltaX=(t.pageX-touchStartX)*touchMult;event.deltaY=(t.pageY-touchStartY)*touchMult;touchStartX=t.pageX;touchStartY=t.pageY;notify(e)}
var onKeyDown=function(e){event.deltaX=event.deltaY=0;switch(e.keyCode){case 37:event.deltaX=-keyStep;break;case 39:event.deltaX=keyStep;break;case 38:event.deltaY=keyStep;break;case 40:event.deltaY=-keyStep;break}
notify(e)}
var initListeners=function(){if(hasWheelEvent)document.addEventListener("wheel",onWheel);if(hasMouseWheelEvent)document.addEventListener("mousewheel",onMouseWheel);if(hasTouch){document.addEventListener("touchstart",onTouchStart);document.addEventListener("touchmove",onTouchMove)}
if(hasPointer&&hasTouchWin){bodyTouchAction=document.body.style.msTouchAction;document.body.style.msTouchAction="none";document.addEventListener("MSPointerDown",onTouchStart,!0);document.addEventListener("MSPointerMove",onTouchMove,!0)}
if(hasKeyDown)document.addEventListener("keydown",onKeyDown);initialized=!0}
var destroyListeners=function(){if(hasWheelEvent)document.removeEventListener("wheel",onWheel);if(hasMouseWheelEvent)document.removeEventListener("mousewheel",onMouseWheel);if(hasTouch){document.removeEventListener("touchstart",onTouchStart);document.removeEventListener("touchmove",onTouchMove)}
if(hasPointer&&hasTouchWin){document.body.style.msTouchAction=bodyTouchAction;document.removeEventListener("MSPointerDown",onTouchStart,!0);document.removeEventListener("MSPointerMove",onTouchMove,!0)}
if(hasKeyDown)document.removeEventListener("keydown",onKeyDown);initialized=!1}
return vs})(document);