jquery.scrollTo.js

/*!
 * jQuery.ScrollTo
 * Copyright (c) 2007-2014 Ariel Flesler - aflesler<a>gmail<d>com | http://flesler.blogspot.com
 * Licensed under MIT
 * http://flesler.blogspot.com/2007/10/jqueryscrollto.html
 * @projectDescription Easy element scrolling using jQuery.
 * @author Ariel Flesler
 * @version 1.4.12
 */

;(function(plugin) {
    // AMD Support
    if (typeof define === 'function' && define.amd) {
        define(['jquery'], plugin);
    } else {
        plugin(jQuery);
    }
}(function($) {

	var $scrollTo = $.scrollTo = function( target, duration, settings ) {
		return $(window).scrollTo( target, duration, settings );
	};

	$scrollTo.defaults = {
		axis:'xy',
		duration: parseFloat($.fn.jquery) >= 1.3 ? 0 : 1,
		limit:true
	};

	// Returns the element that needs to be animated to scroll the window.
	// Kept for backwards compatibility (specially for localScroll & serialScroll)
	$scrollTo.window = function( scope ) {
		return $(window)._scrollable();
	};

	// Hack, hack, hack :)
	// Returns the real elements to scroll (supports window/iframes, documents and regular nodes)
	$.fn._scrollable = function() {
		return this.map(function() {
			var elem = this,
				isWin = !elem.nodeName || $.inArray( elem.nodeName.toLowerCase(), ['iframe','#document','html','body'] ) != -1;

				if (!isWin)
					return elem;

			var doc = (elem.contentWindow || elem).document || elem.ownerDocument || elem;

			return /webkit/i.test(navigator.userAgent) || doc.compatMode == 'BackCompat' ?
				doc.body :
				doc.documentElement;
		});
	};

	$.fn.scrollTo = function( target, duration, settings ) {
		if (typeof duration == 'object') {
			settings = duration;
			duration = 0;
		}
		if (typeof settings == 'function')
			settings = { onAfter:settings };

		if (target == 'max')
			target = 9e9;

		settings = $.extend( {}, $scrollTo.defaults, settings );
		// Speed is still recognized for backwards compatibility
		duration = duration || settings.duration;
		// Make sure the settings are given right
		settings.queue = settings.queue && settings.axis.length > 1;

		if (settings.queue)
			// Let's keep the overall duration
			duration /= 2;
		settings.offset = both( settings.offset );
		settings.over = both( settings.over );

		return this._scrollable().each(function() {
			// Null target yields nothing, just like jQuery does
			if (target == null) return;

			var elem = this,
				$elem = $(elem),
				targ = target, toff, attr = {},
				win = $elem.is('html,body');

			switch (typeof targ) {
				// A number will pass the regex
				case 'number':
				case 'string':
					if (/^([+-]=?)?\d+(\.\d+)?(px|%)?$/.test(targ)) {
						targ = both( targ );
						// We are done
						break;
					}
					// Relative/Absolute selector, no break!
					targ = win ? $(targ) : $(targ, this);
					if (!targ.length) return;
				case 'object':
					// DOMElement / jQuery
					if (targ.is || targ.style)
						// Get the real position of the target
						toff = (targ = $(targ)).offset();
			}
			
			var offset = $.isFunction(settings.offset) && settings.offset(elem, targ) || settings.offset;
			
			$.each( settings.axis.split(''), function( i, axis ) {
				var Pos	= axis == 'x' ? 'Left' : 'Top',
					pos = Pos.toLowerCase(),
					key = 'scroll' + Pos,
					old = elem[key],
					max = $scrollTo.max(elem, axis);

				if (toff) {// jQuery / DOMElement
					attr[key] = toff[pos] + ( win ? 0 : old - $elem.offset()[pos] );

					// If it's a dom element, reduce the margin
					if (settings.margin) {
						attr[key] -= parseInt(targ.css('margin'+Pos)) || 0;
						attr[key] -= parseInt(targ.css('border'+Pos+'Width')) || 0;
					}

					attr[key] += offset[pos] || 0;

					if(settings.over[pos])
						// Scroll to a fraction of its width/height
						attr[key] += targ[axis=='x'?'width':'height']() * settings.over[pos];
				} else {
					var val = targ[pos];
					// Handle percentage values
					attr[key] = val.slice && val.slice(-1) == '%' ?
						parseFloat(val) / 100 * max
						: val;
				}

				// Number or 'number'
				if (settings.limit && /^\d+$/.test(attr[key]))
					// Check the limits
					attr[key] = attr[key] <= 0 ? 0 : Math.min( attr[key], max );

				// Queueing axes
				if (!i && settings.queue) {
					// Don't waste time animating, if there's no need.
					if (old != attr[key])
						// Intermediate animation
						animate( settings.onAfterFirst );
					// Don't animate this axis again in the next iteration.
					delete attr[key];
				}
			});

			animate( settings.onAfter );

			function animate( callback ) {
				$elem.animate( attr, duration, settings.easing, callback && function() {
					callback.call(this, targ, settings);
				});
			};

		}).end();
	};

	// Max scrolling position, works on quirks mode
	// It only fails (not too badly) on IE, quirks mode.
	$scrollTo.max = function( elem, axis ) {
		var Dim = axis == 'x' ? 'Width' : 'Height',
			scroll = 'scroll'+Dim;

		if (!$(elem).is('html,body'))
			return elem[scroll] - $(elem)[Dim.toLowerCase()]();

		var size = 'client' + Dim,
			html = elem.ownerDocument.documentElement,
			body = elem.ownerDocument.body;

		return Math.max( html[scroll], body[scroll] )
			 - Math.min( html[size]  , body[size]   );
	};

	function both( val ) {
		return $.isFunction(val) || typeof val == 'object' ? val : { top:val, left:val };
	};

    // AMD requirement
    return $scrollTo;
}));