/*!

 * jQuery.scrollTo

 * Copyright (c) 2007-2015 Ariel Flesler - aflesler<a>gmail<d>com | http://flesler.blogspot.com

 * Licensed under MIT

 * http://flesler.blogspot.com/2007/10/jqueryscrollto.html

 * @projectDescription Lightweight, cross-browser and highly customizable animated scrolling with jQuery

 * @author Ariel Flesler

 * @version 2.1.1

 */

;(function(factory) {

	'use strict';

	if (typeof define === 'function' && define.amd) {

		// AMD

		define(['jquery'], factory);

	} else if (typeof module !== 'undefined' && module.exports) {

		// CommonJS

		module.exports = factory(require('jquery'));

	} else {

		// Global

		factory(jQuery);

	}

})(function($) {

	'use strict';



	var $scrollTo = $.scrollTo = function(target, duration, settings) {

		return $(window).scrollTo(target, duration, settings);

	};



	$scrollTo.defaults = {

		axis:'xy',

		duration: 0,

		limit:true

	};



	function isWin(elem) {

		return !elem.nodeName ||

			$.inArray(elem.nodeName.toLowerCase(), ['iframe','#document','html','body']) !== -1;

	}		



	$.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

		var queue = settings.queue && settings.axis.length > 1;

		if (queue) {

			// Let's keep the overall duration

			duration /= 2;

		}

		settings.offset = both(settings.offset);

		settings.over = both(settings.over);



		return this.each(function() {

			// Null target yields nothing, just like jQuery does

			if (target === null) return;



			var win = isWin(this),

				elem = win ? this.contentWindow || window : this,

				$elem = $(elem),

				targ = target, 

				attr = {},

				toff;



			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

					targ = win ? $(targ) : $(targ, elem);

					if (!targ.length) return;

					/* falls through */

				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,

					prev = $elem[key](),

					max = $scrollTo.max(elem, axis);



				if (toff) {// jQuery / DOMElement

					attr[key] = toff[pos] + (win ? 0 : prev - $elem.offset()[pos]);



					// If it's a dom element, reduce the margin

					if (settings.margin) {

						attr[key] -= parseInt(targ.css('margin'+Pos), 10) || 0;

						attr[key] -= parseInt(targ.css('border'+Pos+'Width'), 10) || 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);

				}



				// Don't waste time animating, if there's no need.

				if (!i && settings.axis.length > 1) {

					if (prev === attr[key]) {

						// No animation needed

						attr = {};

					} else if (queue) {

						// Intermediate animation

						animate(settings.onAfterFirst);

						// Don't animate this axis again in the next iteration.

						attr = {};

					}

				}

			});



			animate(settings.onAfter);



			function animate(callback) {

				var opts = $.extend({}, settings, {

					// The queue setting conflicts with animate()

					// Force it to always be true

					queue: true,

					duration: duration,

					complete: callback && function() {

						callback.call(elem, targ, settings);

					}

				});

				$elem.animate(attr, opts);

			}

		});

	};



	// 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 (!isWin(elem))

			return elem[scroll] - $(elem)[Dim.toLowerCase()]();



		var size = 'client' + Dim,

			doc = elem.ownerDocument || elem.document,

			html = doc.documentElement,

			body = doc.body;



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

	};



	function both(val) {

		return $.isFunction(val) || $.isPlainObject(val) ? val : { top:val, left:val };

	}



	// Add special hooks so that window scroll properties can be animated

	$.Tween.propHooks.scrollLeft = 

	$.Tween.propHooks.scrollTop = {

		get: function(t) {

			return $(t.elem)[t.prop]();

		},

		set: function(t) {

			var curr = this.get(t);

			// If interrupt is true and user scrolled, stop animating

			if (t.options.interrupt && t._last && t._last !== curr) {

				return $(t.elem).stop();

			}

			var next = Math.round(t.now);

			// Don't waste CPU

			// Browsers don't render floating point scroll

			if (curr !== next) {

				$(t.elem)[t.prop](next);

				t._last = this.get(t);

			}

		}

	};



	// AMD requirement

	return $scrollTo;

});

