PortableMag/ext-lib/iscroll.js

/*!
 * iScroll v4.2.5 ~ Copyright (c) 2012 Matteo Spinelli, http://cubiq.org
 * Released under MIT license, http://cubiq.org/license
 */
(function(window, doc){
var m = Math,
	dummyStyle = doc.createElement('div').style,
	vendor = (function () {
		var vendors = 't,webkitT,MozT,msT,OT'.split(','),
			t,
			i = 0,
			l = vendors.length;

		for ( ; i < l; i++ ) {
			t = vendors[i] + 'ransform';
			if ( t in dummyStyle ) {
				return vendors[i].substr(0, vendors[i].length - 1);
			}
		}

		return false;
	})(),
	cssVendor = vendor ? '-' + vendor.toLowerCase() + '-' : '',

	// Style properties
	transform = prefixStyle('transform'),
	transitionProperty = prefixStyle('transitionProperty'),
	transitionDuration = prefixStyle('transitionDuration'),
	transformOrigin = prefixStyle('transformOrigin'),
	transitionTimingFunction = prefixStyle('transitionTimingFunction'),
	transitionDelay = prefixStyle('transitionDelay'),

    // Browser capabilities
	isAndroid = (/android/gi).test(navigator.appVersion),
	isIDevice = (/iphone|ipad/gi).test(navigator.appVersion),
	isTouchPad = (/hp-tablet/gi).test(navigator.appVersion),

    has3d = prefixStyle('perspective') in dummyStyle,
    hasTouch = 'ontouchstart' in window && !isTouchPad,
    hasTransform = vendor !== false,
    hasTransitionEnd = prefixStyle('transition') in dummyStyle,

	RESIZE_EV = 'onorientationchange' in window ? 'orientationchange' : 'resize',
	START_EV = hasTouch ? 'touchstart' : 'mousedown',
	MOVE_EV = hasTouch ? 'touchmove' : 'mousemove',
	END_EV = hasTouch ? 'touchend' : 'mouseup',
	CANCEL_EV = hasTouch ? 'touchcancel' : 'mouseup',
	TRNEND_EV = (function () {
		if ( vendor === false ) return false;

		var transitionEnd = {
				''			: 'transitionend',
				'webkit'	: 'webkitTransitionEnd',
				'Moz'		: 'transitionend',
				'O'			: 'otransitionend',
				'ms'		: 'MSTransitionEnd'
			};

		return transitionEnd[vendor];
	})(),

	nextFrame = (function() {
		return window.requestAnimationFrame ||
			window.webkitRequestAnimationFrame ||
			window.mozRequestAnimationFrame ||
			window.oRequestAnimationFrame ||
			window.msRequestAnimationFrame ||
			function(callback) { return setTimeout(callback, 1); };
	})(),
	cancelFrame = (function () {
		return window.cancelRequestAnimationFrame ||
			window.webkitCancelAnimationFrame ||
			window.webkitCancelRequestAnimationFrame ||
			window.mozCancelRequestAnimationFrame ||
			window.oCancelRequestAnimationFrame ||
			window.msCancelRequestAnimationFrame ||
			clearTimeout;
	})(),

	// Helpers
	translateZ = has3d ? ' translateZ(0)' : '',

	// Constructor
	iScroll = function (el, options) {
		var that = this,
			i;

		that.wrapper = typeof el == 'object' ? el : doc.getElementById(el);
		that.wrapper.style.overflow = 'hidden';
		that.scroller = that.wrapper.children[0];

		// Default options
		that.options = {
			hScroll: true,
			vScroll: true,
			x: 0,
			y: 0,
			bounce: true,
			bounceLock: false,
			momentum: true,
			lockDirection: true,
			useTransform: true,
			useTransition: false,
			topOffset: 0,
			checkDOMChanges: false,		// Experimental
			handleClick: true,

			// Scrollbar
			hScrollbar: true,
			vScrollbar: true,
			fixedScrollbar: isAndroid,
			hideScrollbar: isIDevice,
			fadeScrollbar: isIDevice && has3d,
			scrollbarClass: '',

			// Zoom
			zoom: false,
			zoomMin: 1,
			zoomMax: 4,
			doubleTapZoom: 2,
			wheelAction: 'scroll',

			// Snap
			snap: false,
			snapThreshold: 1,

			// Events
			onRefresh: null,
			onBeforeScrollStart: function (e) { e.preventDefault(); },
			onScrollStart: null,
			onBeforeScrollMove: null,
			onScrollMove: null,
			onBeforeScrollEnd: null,
			onScrollEnd: null,
			onTouchEnd: null,
			onDestroy: null,
			onZoomStart: null,
			onZoom: null,
			onZoomEnd: null
		};

		// User defined options
		for (i in options) that.options[i] = options[i];
		
		// Set starting position
		that.x = that.options.x;
		that.y = that.options.y;

		// Normalize options
		that.options.useTransform = hasTransform && that.options.useTransform;
		that.options.hScrollbar = that.options.hScroll && that.options.hScrollbar;
		that.options.vScrollbar = that.options.vScroll && that.options.vScrollbar;
		that.options.zoom = that.options.useTransform && that.options.zoom;
		that.options.useTransition = hasTransitionEnd && that.options.useTransition;

		// Helpers FIX ANDROID BUG!
		// translate3d and scale doesn't work together!
		// Ignoring 3d ONLY WHEN YOU SET that.options.zoom
		if ( that.options.zoom && isAndroid ){
			translateZ = '';
		}
		
		// Set some default styles
		that.scroller.style[transitionProperty] = that.options.useTransform ? cssVendor + 'transform' : 'top left';
		that.scroller.style[transitionDuration] = '0';
		that.scroller.style[transformOrigin] = '0 0';
		if (that.options.useTransition) that.scroller.style[transitionTimingFunction] = 'cubic-bezier(0.33,0.66,0.66,1)';
		
		if (that.options.useTransform) that.scroller.style[transform] = 'translate(' + that.x + 'px,' + that.y + 'px)' + translateZ;
		else that.scroller.style.cssText += ';position:absolute;top:' + that.y + 'px;left:' + that.x + 'px';

		if (that.options.useTransition) that.options.fixedScrollbar = true;

		that.refresh();

		that._bind(RESIZE_EV, window);
		that._bind(START_EV);
		if (!hasTouch) {
			if (that.options.wheelAction != 'none') {
				that._bind('DOMMouseScroll');
				that._bind('mousewheel');
			}
		}

		if (that.options.checkDOMChanges) that.checkDOMTime = setInterval(function () {
			that._checkDOMChanges();
		}, 500);
	};

// Prototype
iScroll.prototype = {
	enabled: true,
	x: 0,
	y: 0,
	steps: [],
	scale: 1,
	currPageX: 0, currPageY: 0,
	pagesX: [], pagesY: [],
	aniTime: null,
	wheelZoomCount: 0,
	
	handleEvent: function (e) {
		var that = this;
		switch(e.type) {
			case START_EV:
				if (!hasTouch && e.button !== 0) return;
				that._start(e);
				break;
			case MOVE_EV: that._move(e); break;
			case END_EV:
			case CANCEL_EV: that._end(e); break;
			case RESIZE_EV: that._resize(); break;
			case 'DOMMouseScroll': case 'mousewheel': that._wheel(e); break;
			case TRNEND_EV: that._transitionEnd(e); break;
		}
	},
	
	_checkDOMChanges: function () {
		if (this.moved || this.zoomed || this.animating ||
			(this.scrollerW == this.scroller.offsetWidth * this.scale && this.scrollerH == this.scroller.offsetHeight * this.scale)) return;

		this.refresh();
	},
	
	_scrollbar: function (dir) {
		var that = this,
			bar;

		if (!that[dir + 'Scrollbar']) {
			if (that[dir + 'ScrollbarWrapper']) {
				if (hasTransform) that[dir + 'ScrollbarIndicator'].style[transform] = '';
				that[dir + 'ScrollbarWrapper'].parentNode.removeChild(that[dir + 'ScrollbarWrapper']);
				that[dir + 'ScrollbarWrapper'] = null;
				that[dir + 'ScrollbarIndicator'] = null;
			}

			return;
		}

		if (!that[dir + 'ScrollbarWrapper']) {
			// Create the scrollbar wrapper
			bar = doc.createElement('div');

			if (that.options.scrollbarClass) bar.className = that.options.scrollbarClass + dir.toUpperCase();
			else bar.style.cssText = 'position:absolute;z-index:100;' + (dir == 'h' ? 'height:7px;bottom:1px;left:2px;right:' + (that.vScrollbar ? '7' : '2') + 'px' : 'width:7px;bottom:' + (that.hScrollbar ? '7' : '2') + 'px;top:2px;right:1px');

			bar.style.cssText += ';pointer-events:none;' + cssVendor + 'transition-property:opacity;' + cssVendor + 'transition-duration:' + (that.options.fadeScrollbar ? '350ms' : '0') + ';overflow:hidden;opacity:' + (that.options.hideScrollbar ? '0' : '1');

			that.wrapper.appendChild(bar);
			that[dir + 'ScrollbarWrapper'] = bar;

			// Create the scrollbar indicator
			bar = doc.createElement('div');
			if (!that.options.scrollbarClass) {
				bar.style.cssText = 'position:absolute;z-index:100;background:rgba(0,0,0,0.5);border:1px solid rgba(255,255,255,0.9);' + cssVendor + 'background-clip:padding-box;' + cssVendor + 'box-sizing:border-box;' + (dir == 'h' ? 'height:100%' : 'width:100%') + ';' + cssVendor + 'border-radius:3px;border-radius:3px';
			}
			bar.style.cssText += ';pointer-events:none;' + cssVendor + 'transition-property:' + cssVendor + 'transform;' + cssVendor + 'transition-timing-function:cubic-bezier(0.33,0.66,0.66,1);' + cssVendor + 'transition-duration:0;' + cssVendor + 'transform: translate(0,0)' + translateZ;
			if (that.options.useTransition) bar.style.cssText += ';' + cssVendor + 'transition-timing-function:cubic-bezier(0.33,0.66,0.66,1)';

			that[dir + 'ScrollbarWrapper'].appendChild(bar);
			that[dir + 'ScrollbarIndicator'] = bar;
		}

		if (dir == 'h') {
			that.hScrollbarSize = that.hScrollbarWrapper.clientWidth;
			that.hScrollbarIndicatorSize = m.max(m.round(that.hScrollbarSize * that.hScrollbarSize / that.scrollerW), 8);
			that.hScrollbarIndicator.style.width = that.hScrollbarIndicatorSize + 'px';
			that.hScrollbarMaxScroll = that.hScrollbarSize - that.hScrollbarIndicatorSize;
			that.hScrollbarProp = that.hScrollbarMaxScroll / that.maxScrollX;
		} else {
			that.vScrollbarSize = that.vScrollbarWrapper.clientHeight;
			that.vScrollbarIndicatorSize = m.max(m.round(that.vScrollbarSize * that.vScrollbarSize / that.scrollerH), 8);
			that.vScrollbarIndicator.style.height = that.vScrollbarIndicatorSize + 'px';
			that.vScrollbarMaxScroll = that.vScrollbarSize - that.vScrollbarIndicatorSize;
			that.vScrollbarProp = that.vScrollbarMaxScroll / that.maxScrollY;
		}

		// Reset position
		that._scrollbarPos(dir, true);
	},
	
	_resize: function () {
		var that = this;
		setTimeout(function () { that.refresh(); }, isAndroid ? 200 : 0);
	},
	
	_pos: function (x, y) {
		if (this.zoomed) return;

		x = this.hScroll ? x : 0;
		y = this.vScroll ? y : 0;

		if (this.options.useTransform) {
			this.scroller.style[transform] = 'translate(' + x + 'px,' + y + 'px) scale(' + this.scale + ')' + translateZ;
		} else {
			x = m.round(x);
			y = m.round(y);
			this.scroller.style.left = x + 'px';
			this.scroller.style.top = y + 'px';
		}

		this.x = x;
		this.y = y;

		this._scrollbarPos('h');
		this._scrollbarPos('v');
	},

	_scrollbarPos: function (dir, hidden) {
		var that = this,
			pos = dir == 'h' ? that.x : that.y,
			size;

		if (!that[dir + 'Scrollbar']) return;

		pos = that[dir + 'ScrollbarProp'] * pos;

		if (pos < 0) {
			if (!that.options.fixedScrollbar) {
				size = that[dir + 'ScrollbarIndicatorSize'] + m.round(pos * 3);
				if (size < 8) size = 8;
				that[dir + 'ScrollbarIndicator'].style[dir == 'h' ? 'width' : 'height'] = size + 'px';
			}
			pos = 0;
		} else if (pos > that[dir + 'ScrollbarMaxScroll']) {
			if (!that.options.fixedScrollbar) {
				size = that[dir + 'ScrollbarIndicatorSize'] - m.round((pos - that[dir + 'ScrollbarMaxScroll']) * 3);
				if (size < 8) size = 8;
				that[dir + 'ScrollbarIndicator'].style[dir == 'h' ? 'width' : 'height'] = size + 'px';
				pos = that[dir + 'ScrollbarMaxScroll'] + (that[dir + 'ScrollbarIndicatorSize'] - size);
			} else {
				pos = that[dir + 'ScrollbarMaxScroll'];
			}
		}

		that[dir + 'ScrollbarWrapper'].style[transitionDelay] = '0';
		that[dir + 'ScrollbarWrapper'].style.opacity = hidden && that.options.hideScrollbar ? '0' : '1';
		that[dir + 'ScrollbarIndicator'].style[transform] = 'translate(' + (dir == 'h' ? pos + 'px,0)' : '0,' + pos + 'px)') + translateZ;
	},
	
	_start: function (e) {
		var that = this,
			point = hasTouch ? e.touches[0] : e,
			matrix, x, y,
			c1, c2;

		if (!that.enabled) return;

		if (that.options.onBeforeScrollStart) that.options.onBeforeScrollStart.call(that, e);

		if (that.options.useTransition || that.options.zoom) that._transitionTime(0);

		that.moved = false;
		that.animating = false;
		that.zoomed = false;
		that.distX = 0;
		that.distY = 0;
		that.absDistX = 0;
		that.absDistY = 0;
		that.dirX = 0;
		that.dirY = 0;

		// Gesture start
		if (that.options.zoom && hasTouch && e.touches.length > 1) {
			c1 = m.abs(e.touches[0].pageX-e.touches[1].pageX);
			c2 = m.abs(e.touches[0].pageY-e.touches[1].pageY);
			that.touchesDistStart = m.sqrt(c1 * c1 + c2 * c2);

			that.originX = m.abs(e.touches[0].pageX + e.touches[1].pageX - that.wrapperOffsetLeft * 2) / 2 - that.x;
			that.originY = m.abs(e.touches[0].pageY + e.touches[1].pageY - that.wrapperOffsetTop * 2) / 2 - that.y;

			if (that.options.onZoomStart) that.options.onZoomStart.call(that, e);
		}

		if (that.options.momentum) {
			if (that.options.useTransform) {
				// Very lame general purpose alternative to CSSMatrix
				matrix = getComputedStyle(that.scroller, null)[transform].replace(/[^0-9\-.,]/g, '').split(',');
				x = +(matrix[12] || matrix[4]);
				y = +(matrix[13] || matrix[5]);
			} else {
				x = +getComputedStyle(that.scroller, null).left.replace(/[^0-9-]/g, '');
				y = +getComputedStyle(that.scroller, null).top.replace(/[^0-9-]/g, '');
			}
			
			if (x != that.x || y != that.y) {
				if (that.options.useTransition) that._unbind(TRNEND_EV);
				else cancelFrame(that.aniTime);
				that.steps = [];
				that._pos(x, y);
				if (that.options.onScrollEnd) that.options.onScrollEnd.call(that);
			}
		}

		that.absStartX = that.x;	// Needed by snap threshold
		that.absStartY = that.y;

		that.startX = that.x;
		that.startY = that.y;
		that.pointX = point.pageX;
		that.pointY = point.pageY;

		that.startTime = e.timeStamp || Date.now();

		if (that.options.onScrollStart) that.options.onScrollStart.call(that, e);

		that._bind(MOVE_EV, window);
		that._bind(END_EV, window);
		that._bind(CANCEL_EV, window);
	},
	
	_move: function (e) {
		var that = this,
			point = hasTouch ? e.touches[0] : e,
			deltaX = point.pageX - that.pointX,
			deltaY = point.pageY - that.pointY,
			newX = that.x + deltaX,
			newY = that.y + deltaY,
			c1, c2, scale,
			timestamp = e.timeStamp || Date.now();

		if (that.options.onBeforeScrollMove) that.options.onBeforeScrollMove.call(that, e);

		// Zoom
		if (that.options.zoom && hasTouch && e.touches.length > 1) {
			c1 = m.abs(e.touches[0].pageX - e.touches[1].pageX);
			c2 = m.abs(e.touches[0].pageY - e.touches[1].pageY);
			that.touchesDist = m.sqrt(c1*c1+c2*c2);

			that.zoomed = true;

			scale = 1 / that.touchesDistStart * that.touchesDist * this.scale;

			if (scale < that.options.zoomMin) scale = 0.5 * that.options.zoomMin * Math.pow(2.0, scale / that.options.zoomMin);
			else if (scale > that.options.zoomMax) scale = 2.0 * that.options.zoomMax * Math.pow(0.5, that.options.zoomMax / scale);

			that.lastScale = scale / this.scale;

			newX = this.originX - this.originX * that.lastScale + this.x,
			newY = this.originY - this.originY * that.lastScale + this.y;

			this.scroller.style[transform] = 'translate(' + newX + 'px,' + newY + 'px) scale(' + scale + ')' + translateZ;

			if (that.options.onZoom) that.options.onZoom.call(that, e);
			return;
		}

		that.pointX = point.pageX;
		that.pointY = point.pageY;

		// Slow down if outside of the boundaries
		if (newX > 0 || newX < that.maxScrollX) {
			newX = that.options.bounce ? that.x + (deltaX / 2) : newX >= 0 || that.maxScrollX >= 0 ? 0 : that.maxScrollX;
		}
		if (newY > that.minScrollY || newY < that.maxScrollY) {
			newY = that.options.bounce ? that.y + (deltaY / 2) : newY >= that.minScrollY || that.maxScrollY >= 0 ? that.minScrollY : that.maxScrollY;
		}

		that.distX += deltaX;
		that.distY += deltaY;
		that.absDistX = m.abs(that.distX);
		that.absDistY = m.abs(that.distY);

		if (that.absDistX < 6 && that.absDistY < 6) {
			return;
		}

		// Lock direction
		if (that.options.lockDirection) {
			if (that.absDistX > that.absDistY + 5) {
				newY = that.y;
				deltaY = 0;
			} else if (that.absDistY > that.absDistX + 5) {
				newX = that.x;
				deltaX = 0;
			}
		}

		that.moved = true;
		that._pos(newX, newY);
		that.dirX = deltaX > 0 ? -1 : deltaX < 0 ? 1 : 0;
		that.dirY = deltaY > 0 ? -1 : deltaY < 0 ? 1 : 0;

		if (timestamp - that.startTime > 300) {
			that.startTime = timestamp;
			that.startX = that.x;
			that.startY = that.y;
		}
		
		if (that.options.onScrollMove) that.options.onScrollMove.call(that, e);
	},
	
	_end: function (e) {
		if (hasTouch && e.touches.length !== 0) return;

		var that = this,
			point = hasTouch ? e.changedTouches[0] : e,
			target, ev,
			momentumX = { dist:0, time:0 },
			momentumY = { dist:0, time:0 },
			duration = (e.timeStamp || Date.now()) - that.startTime,
			newPosX = that.x,
			newPosY = that.y,
			distX, distY,
			newDuration,
			snap,
			scale;

		that._unbind(MOVE_EV, window);
		that._unbind(END_EV, window);
		that._unbind(CANCEL_EV, window);

		if (that.options.onBeforeScrollEnd) that.options.onBeforeScrollEnd.call(that, e);

		if (that.zoomed) {
			scale = that.scale * that.lastScale;
			scale = Math.max(that.options.zoomMin, scale);
			scale = Math.min(that.options.zoomMax, scale);
			that.lastScale = scale / that.scale;
			that.scale = scale;

			that.x = that.originX - that.originX * that.lastScale + that.x;
			that.y = that.originY - that.originY * that.lastScale + that.y;
			
			that.scroller.style[transitionDuration] = '200ms';
			that.scroller.style[transform] = 'translate(' + that.x + 'px,' + that.y + 'px) scale(' + that.scale + ')' + translateZ;
			
			that.zoomed = false;
			that.refresh();

			if (that.options.onZoomEnd) that.options.onZoomEnd.call(that, e);
			return;
		}

		if (!that.moved) {
			if (hasTouch) {
				if (that.doubleTapTimer && that.options.zoom) {
					// Double tapped
					clearTimeout(that.doubleTapTimer);
					that.doubleTapTimer = null;
					if (that.options.onZoomStart) that.options.onZoomStart.call(that, e);
					that.zoom(that.pointX, that.pointY, that.scale == 1 ? that.options.doubleTapZoom : 1);
					if (that.options.onZoomEnd) {
						setTimeout(function() {
							that.options.onZoomEnd.call(that, e);
						}, 200); // 200 is default zoom duration
					}
				} else if (this.options.handleClick) {
					that.doubleTapTimer = setTimeout(function () {
						that.doubleTapTimer = null;

						// Find the last touched element
						target = point.target;
						while (target.nodeType != 1) target = target.parentNode;

						if (target.tagName != 'SELECT' && target.tagName != 'INPUT' && target.tagName != 'TEXTAREA') {
							ev = doc.createEvent('MouseEvents');
							ev.initMouseEvent('click', true, true, e.view, 1,
								point.screenX, point.screenY, point.clientX, point.clientY,
								e.ctrlKey, e.altKey, e.shiftKey, e.metaKey,
								0, null);
							ev._fake = true;
							target.dispatchEvent(ev);
						}
					}, that.options.zoom ? 250 : 0);
				}
			}

			that._resetPos(400);

			if (that.options.onTouchEnd) that.options.onTouchEnd.call(that, e);
			return;
		}

		if (duration < 300 && that.options.momentum) {
			momentumX = newPosX ? that._momentum(newPosX - that.startX, duration, -that.x, that.scrollerW - that.wrapperW + that.x, that.options.bounce ? that.wrapperW : 0) : momentumX;
			momentumY = newPosY ? that._momentum(newPosY - that.startY, duration, -that.y, (that.maxScrollY < 0 ? that.scrollerH - that.wrapperH + that.y - that.minScrollY : 0), that.options.bounce ? that.wrapperH : 0) : momentumY;

			newPosX = that.x + momentumX.dist;
			newPosY = that.y + momentumY.dist;

			if ((that.x > 0 && newPosX > 0) || (that.x < that.maxScrollX && newPosX < that.maxScrollX)) momentumX = { dist:0, time:0 };
			if ((that.y > that.minScrollY && newPosY > that.minScrollY) || (that.y < that.maxScrollY && newPosY < that.maxScrollY)) momentumY = { dist:0, time:0 };
		}

		if (momentumX.dist || momentumY.dist) {
			newDuration = m.max(m.max(momentumX.time, momentumY.time), 10);

			// Do we need to snap?
			if (that.options.snap) {
				distX = newPosX - that.absStartX;
				distY = newPosY - that.absStartY;
				if (m.abs(distX) < that.options.snapThreshold && m.abs(distY) < that.options.snapThreshold) { that.scrollTo(that.absStartX, that.absStartY, 200); }
				else {
					snap = that._snap(newPosX, newPosY);
					newPosX = snap.x;
					newPosY = snap.y;
					newDuration = m.max(snap.time, newDuration);
				}
			}

			that.scrollTo(m.round(newPosX), m.round(newPosY), newDuration);

			if (that.options.onTouchEnd) that.options.onTouchEnd.call(that, e);
			return;
		}

		// Do we need to snap?
		if (that.options.snap) {
			distX = newPosX - that.absStartX;
			distY = newPosY - that.absStartY;
			if (m.abs(distX) < that.options.snapThreshold && m.abs(distY) < that.options.snapThreshold) that.scrollTo(that.absStartX, that.absStartY, 200);
			else {
				snap = that._snap(that.x, that.y);
				if (snap.x != that.x || snap.y != that.y) that.scrollTo(snap.x, snap.y, snap.time);
			}

			if (that.options.onTouchEnd) that.options.onTouchEnd.call(that, e);
			return;
		}

		that._resetPos(200);
		if (that.options.onTouchEnd) that.options.onTouchEnd.call(that, e);
	},
	
	_resetPos: function (time) {
		var that = this,
			resetX = that.x >= 0 ? 0 : that.x < that.maxScrollX ? that.maxScrollX : that.x,
			resetY = that.y >= that.minScrollY || that.maxScrollY > 0 ? that.minScrollY : that.y < that.maxScrollY ? that.maxScrollY : that.y;

		if (resetX == that.x && resetY == that.y) {
			if (that.moved) {
				that.moved = false;
				if (that.options.onScrollEnd) that.options.onScrollEnd.call(that);		// Execute custom code on scroll end
			}

			if (that.hScrollbar && that.options.hideScrollbar) {
				if (vendor == 'webkit') that.hScrollbarWrapper.style[transitionDelay] = '300ms';
				that.hScrollbarWrapper.style.opacity = '0';
			}
			if (that.vScrollbar && that.options.hideScrollbar) {
				if (vendor == 'webkit') that.vScrollbarWrapper.style[transitionDelay] = '300ms';
				that.vScrollbarWrapper.style.opacity = '0';
			}

			return;
		}

		that.scrollTo(resetX, resetY, time || 0);
	},

	_wheel: function (e) {
		var that = this,
			wheelDeltaX, wheelDeltaY,
			deltaX, deltaY,
			deltaScale;

		if ('wheelDeltaX' in e) {
			wheelDeltaX = e.wheelDeltaX / 12;
			wheelDeltaY = e.wheelDeltaY / 12;
		} else if('wheelDelta' in e) {
			wheelDeltaX = wheelDeltaY = e.wheelDelta / 12;
		} else if ('detail' in e) {
			wheelDeltaX = wheelDeltaY = -e.detail * 3;
		} else {
			return;
		}
		
		if (that.options.wheelAction == 'zoom') {
			deltaScale = that.scale * Math.pow(2, 1/3 * (wheelDeltaY ? wheelDeltaY / Math.abs(wheelDeltaY) : 0));
			if (deltaScale < that.options.zoomMin) deltaScale = that.options.zoomMin;
			if (deltaScale > that.options.zoomMax) deltaScale = that.options.zoomMax;
			
			if (deltaScale != that.scale) {
				if (!that.wheelZoomCount && that.options.onZoomStart) that.options.onZoomStart.call(that, e);
				that.wheelZoomCount++;
				
				that.zoom(e.pageX, e.pageY, deltaScale, 400);
				
				setTimeout(function() {
					that.wheelZoomCount--;
					if (!that.wheelZoomCount && that.options.onZoomEnd) that.options.onZoomEnd.call(that, e);
				}, 400);
			}
			
			return;
		}
		
		deltaX = that.x + wheelDeltaX;
		deltaY = that.y + wheelDeltaY;

		if (deltaX > 0) deltaX = 0;
		else if (deltaX < that.maxScrollX) deltaX = that.maxScrollX;

		if (deltaY > that.minScrollY) deltaY = that.minScrollY;
		else if (deltaY < that.maxScrollY) deltaY = that.maxScrollY;
    
		if (that.maxScrollY < 0) {
			that.scrollTo(deltaX, deltaY, 0);
		}
	},
	
	_transitionEnd: function (e) {
		var that = this;

		if (e.target != that.scroller) return;

		that._unbind(TRNEND_EV);
		
		that._startAni();
	},


	/**
	*
	* Utilities
	*
	*/
	_startAni: function () {
		var that = this,
			startX = that.x, startY = that.y,
			startTime = Date.now(),
			step, easeOut,
			animate;

		if (that.animating) return;
		
		if (!that.steps.length) {
			that._resetPos(400);
			return;
		}
		
		step = that.steps.shift();
		
		if (step.x == startX && step.y == startY) step.time = 0;

		that.animating = true;
		that.moved = true;
		
		if (that.options.useTransition) {
			that._transitionTime(step.time);
			that._pos(step.x, step.y);
			that.animating = false;
			if (step.time) that._bind(TRNEND_EV);
			else that._resetPos(0);
			return;
		}

		animate = function () {
			var now = Date.now(),
				newX, newY;

			if (now >= startTime + step.time) {
				that._pos(step.x, step.y);
				that.animating = false;
				if (that.options.onAnimationEnd) that.options.onAnimationEnd.call(that);			// Execute custom code on animation end
				that._startAni();
				return;
			}

			now = (now - startTime) / step.time - 1;
			easeOut = m.sqrt(1 - now * now);
			newX = (step.x - startX) * easeOut + startX;
			newY = (step.y - startY) * easeOut + startY;
			that._pos(newX, newY);
			if (that.animating) that.aniTime = nextFrame(animate);
		};

		animate();
	},

	_transitionTime: function (time) {
		time += 'ms';
		this.scroller.style[transitionDuration] = time;
		if (this.hScrollbar) this.hScrollbarIndicator.style[transitionDuration] = time;
		if (this.vScrollbar) this.vScrollbarIndicator.style[transitionDuration] = time;
	},

	_momentum: function (dist, time, maxDistUpper, maxDistLower, size) {
		var deceleration = 0.0006,
			speed = m.abs(dist) / time,
			newDist = (speed * speed) / (2 * deceleration),
			newTime = 0, outsideDist = 0;

		// Proportinally reduce speed if we are outside of the boundaries
		if (dist > 0 && newDist > maxDistUpper) {
			outsideDist = size / (6 / (newDist / speed * deceleration));
			maxDistUpper = maxDistUpper + outsideDist;
			speed = speed * maxDistUpper / newDist;
			newDist = maxDistUpper;
		} else if (dist < 0 && newDist > maxDistLower) {
			outsideDist = size / (6 / (newDist / speed * deceleration));
			maxDistLower = maxDistLower + outsideDist;
			speed = speed * maxDistLower / newDist;
			newDist = maxDistLower;
		}

		newDist = newDist * (dist < 0 ? -1 : 1);
		newTime = speed / deceleration;

		return { dist: newDist, time: m.round(newTime) };
	},

	_offset: function (el) {
		var left = -el.offsetLeft,
			top = -el.offsetTop;
			
		while (el = el.offsetParent) {
			left -= el.offsetLeft;
			top -= el.offsetTop;
		}
		
		if (el != this.wrapper) {
			left *= this.scale;
			top *= this.scale;
		}

		return { left: left, top: top };
	},

	_snap: function (x, y) {
		var that = this,
			i, l,
			page, time,
			sizeX, sizeY;

		// Check page X
		page = that.pagesX.length - 1;
		for (i=0, l=that.pagesX.length; i<l; i++) {
			if (x >= that.pagesX[i]) {
				page = i;
				break;
			}
		}
		if (page == that.currPageX && page > 0 && that.dirX < 0) page--;
		x = that.pagesX[page];
		sizeX = m.abs(x - that.pagesX[that.currPageX]);
		sizeX = sizeX ? m.abs(that.x - x) / sizeX * 500 : 0;
		that.currPageX = page;

		// Check page Y
		page = that.pagesY.length-1;
		for (i=0; i<page; i++) {
			if (y >= that.pagesY[i]) {
				page = i;
				break;
			}
		}
		if (page == that.currPageY && page > 0 && that.dirY < 0) page--;
		y = that.pagesY[page];
		sizeY = m.abs(y - that.pagesY[that.currPageY]);
		sizeY = sizeY ? m.abs(that.y - y) / sizeY * 500 : 0;
		that.currPageY = page;

		// Snap with constant speed (proportional duration)
		time = m.round(m.max(sizeX, sizeY)) || 200;

		return { x: x, y: y, time: time };
	},

	_bind: function (type, el, bubble) {
		(el || this.scroller).addEventListener(type, this, !!bubble);
	},

	_unbind: function (type, el, bubble) {
		(el || this.scroller).removeEventListener(type, this, !!bubble);
	},


	/**
	*
	* Public methods
	*
	*/
	destroy: function () {
		var that = this;

		that.scroller.style[transform] = '';

		// Remove the scrollbars
		that.hScrollbar = false;
		that.vScrollbar = false;
		that._scrollbar('h');
		that._scrollbar('v');

		// Remove the event listeners
		that._unbind(RESIZE_EV, window);
		that._unbind(START_EV);
		that._unbind(MOVE_EV, window);
		that._unbind(END_EV, window);
		that._unbind(CANCEL_EV, window);
		
		if (!that.options.hasTouch) {
			that._unbind('DOMMouseScroll');
			that._unbind('mousewheel');
		}
		
		if (that.options.useTransition) that._unbind(TRNEND_EV);
		
		if (that.options.checkDOMChanges) clearInterval(that.checkDOMTime);
		
		if (that.options.onDestroy) that.options.onDestroy.call(that);
	},

	refresh: function () {
		var that = this,
			offset,
			i, l,
			els,
			pos = 0,
			page = 0;

		if (that.scale < that.options.zoomMin) that.scale = that.options.zoomMin;
		that.wrapperW = that.wrapper.clientWidth || 1;
		that.wrapperH = that.wrapper.clientHeight || 1;

		that.minScrollY = -that.options.topOffset || 0;
		that.scrollerW = m.round(that.scroller.offsetWidth * that.scale);
		that.scrollerH = m.round((that.scroller.offsetHeight + that.minScrollY) * that.scale);
		that.maxScrollX = that.wrapperW - that.scrollerW;
		that.maxScrollY = that.wrapperH - that.scrollerH + that.minScrollY;
		that.dirX = 0;
		that.dirY = 0;

		if (that.options.onRefresh) that.options.onRefresh.call(that);

		that.hScroll = that.options.hScroll && that.maxScrollX < 0;
		that.vScroll = that.options.vScroll && (!that.options.bounceLock && !that.hScroll || that.scrollerH > that.wrapperH);

		that.hScrollbar = that.hScroll && that.options.hScrollbar;
		that.vScrollbar = that.vScroll && that.options.vScrollbar && that.scrollerH > that.wrapperH;

		offset = that._offset(that.wrapper);
		that.wrapperOffsetLeft = -offset.left;
		that.wrapperOffsetTop = -offset.top;

		// Prepare snap
		if (typeof that.options.snap == 'string') {
			that.pagesX = [];
			that.pagesY = [];
			els = that.scroller.querySelectorAll(that.options.snap);
			for (i=0, l=els.length; i<l; i++) {
				pos = that._offset(els[i]);
				pos.left += that.wrapperOffsetLeft;
				pos.top += that.wrapperOffsetTop;
				that.pagesX[i] = pos.left < that.maxScrollX ? that.maxScrollX : pos.left * that.scale;
				that.pagesY[i] = pos.top < that.maxScrollY ? that.maxScrollY : pos.top * that.scale;
			}
		} else if (that.options.snap) {
			that.pagesX = [];
			while (pos >= that.maxScrollX) {
				that.pagesX[page] = pos;
				pos = pos - that.wrapperW;
				page++;
			}
			if (that.maxScrollX%that.wrapperW) that.pagesX[that.pagesX.length] = that.maxScrollX - that.pagesX[that.pagesX.length-1] + that.pagesX[that.pagesX.length-1];

			pos = 0;
			page = 0;
			that.pagesY = [];
			while (pos >= that.maxScrollY) {
				that.pagesY[page] = pos;
				pos = pos - that.wrapperH;
				page++;
			}
			if (that.maxScrollY%that.wrapperH) that.pagesY[that.pagesY.length] = that.maxScrollY - that.pagesY[that.pagesY.length-1] + that.pagesY[that.pagesY.length-1];
		}

		// Prepare the scrollbars
		that._scrollbar('h');
		that._scrollbar('v');

		if (!that.zoomed) {
			that.scroller.style[transitionDuration] = '0';
			that._resetPos(400);
		}
	},

	scrollTo: function (x, y, time, relative) {
		var that = this,
			step = x,
			i, l;

		that.stop();

		if (!step.length) step = [{ x: x, y: y, time: time, relative: relative }];
		
		for (i=0, l=step.length; i<l; i++) {
			if (step[i].relative) { step[i].x = that.x - step[i].x; step[i].y = that.y - step[i].y; }
			that.steps.push({ x: step[i].x, y: step[i].y, time: step[i].time || 0 });
		}

		that._startAni();
	},

	scrollToElement: function (el, time) {
		var that = this, pos;
		el = el.nodeType ? el : that.scroller.querySelector(el);
		if (!el) return;

		pos = that._offset(el);
		pos.left += that.wrapperOffsetLeft;
		pos.top += that.wrapperOffsetTop;

		pos.left = pos.left > 0 ? 0 : pos.left < that.maxScrollX ? that.maxScrollX : pos.left;
		pos.top = pos.top > that.minScrollY ? that.minScrollY : pos.top < that.maxScrollY ? that.maxScrollY : pos.top;
		time = time === undefined ? m.max(m.abs(pos.left)*2, m.abs(pos.top)*2) : time;

		that.scrollTo(pos.left, pos.top, time);
	},

	scrollToPage: function (pageX, pageY, time) {
		var that = this, x, y;
		
		time = time === undefined ? 400 : time;

		if (that.options.onScrollStart) that.options.onScrollStart.call(that);

		if (that.options.snap) {
			pageX = pageX == 'next' ? that.currPageX+1 : pageX == 'prev' ? that.currPageX-1 : pageX;
			pageY = pageY == 'next' ? that.currPageY+1 : pageY == 'prev' ? that.currPageY-1 : pageY;

			pageX = pageX < 0 ? 0 : pageX > that.pagesX.length-1 ? that.pagesX.length-1 : pageX;
			pageY = pageY < 0 ? 0 : pageY > that.pagesY.length-1 ? that.pagesY.length-1 : pageY;

			that.currPageX = pageX;
			that.currPageY = pageY;
			x = that.pagesX[pageX];
			y = that.pagesY[pageY];
		} else {
			x = -that.wrapperW * pageX;
			y = -that.wrapperH * pageY;
			if (x < that.maxScrollX) x = that.maxScrollX;
			if (y < that.maxScrollY) y = that.maxScrollY;
		}

		that.scrollTo(x, y, time);
	},

	disable: function () {
		this.stop();
		this._resetPos(0);
		this.enabled = false;

		// If disabled after touchstart we make sure that there are no left over events
		this._unbind(MOVE_EV, window);
		this._unbind(END_EV, window);
		this._unbind(CANCEL_EV, window);
	},
	
	enable: function () {
		this.enabled = true;
	},
	
	stop: function () {
		if (this.options.useTransition) this._unbind(TRNEND_EV);
		else cancelFrame(this.aniTime);
		this.steps = [];
		this.moved = false;
		this.animating = false;
	},
	
	zoom: function (x, y, scale, time) {
		var that = this,
			relScale = scale / that.scale;

		if (!that.options.useTransform) return;

		that.zoomed = true;
		time = time === undefined ? 200 : time;
		x = x - that.wrapperOffsetLeft - that.x;
		y = y - that.wrapperOffsetTop - that.y;
		that.x = x - x * relScale + that.x;
		that.y = y - y * relScale + that.y;

		that.scale = scale;
		that.refresh();

		that.x = that.x > 0 ? 0 : that.x < that.maxScrollX ? that.maxScrollX : that.x;
		that.y = that.y > that.minScrollY ? that.minScrollY : that.y < that.maxScrollY ? that.maxScrollY : that.y;

		that.scroller.style[transitionDuration] = time + 'ms';
		that.scroller.style[transform] = 'translate(' + that.x + 'px,' + that.y + 'px) scale(' + scale + ')' + translateZ;
		that.zoomed = false;
	},
	
	isReady: function () {
		return !this.moved && !this.zoomed && !this.animating;
	}
};

function prefixStyle (style) {
	if ( vendor === '' ) return style;

	style = style.charAt(0).toUpperCase() + style.substr(1);
	return vendor + style;
}

dummyStyle = null;	// for the sake of it

if (typeof exports !== 'undefined') exports.iScroll = iScroll;
else window.iScroll = iScroll;

})(window, document);