/**
 * jquery.localscroll
 * copyright (c) 2007-2008 ariel flesler - aflesler(at)gmail(dot)com | http://flesler.blogspot.com
 * dual licensed under mit and gpl.
 * date: 3/10/2008
 *
 * @projectdescription animated scrolling navigation, using anchors.
 * http://flesler.blogspot.com/2007/10/jquerylocalscroll-10.html
 * @author ariel flesler
 * @version 1.2.5
 *
 * @id jquery.fn.localscroll
 * @param {object} settings hash of settings, it is passed in to jquery.scrollto, none is required.
 * @return {jquery} returns the same jquery object, for chaining.
 *
 * @example $('ul.links').localscroll();
 *
 * @example $('ul.links').localscroll({ filter:'.animated', duration:400, axis:'x' });
 *
 * @example $.localscroll({ target:'#pane', axis:'xy', queue:true, event:'mouseover' });
 *
 * notes:
 *	- the plugin requires jquery.scrollto.
 *	- the hash of settings, is passed to jquery.scrollto, so the settings are valid for that plugin as well.
 *	- jquery.localscroll can be used if the desired links, are all over the document, it accepts the same settings.
 *  - if the setting 'lazy' is set to true, then the binding will still work for later added anchors.
 *  - the setting 'speed' is deprecated, use 'duration' instead.
 *	- if onbefore returns false, the event is ignored.
 **/
;(function( $ ){
	var uri = location.href.replace(/#.*/,'');//local url without hash

	var $localscroll = $.localscroll = function( settings ){
		$('body').localscroll( settings );
	};

	//many of these defaults, belong to jquery.scrollto, check it's demo for an example of each option.
	//@see http://www.freewebs.com/flesler/jquery.scrollto/
	$localscroll.defaults = {//the defaults are public and can be overriden.
		duration:1000, //how long to animate.
		axis:'y',//which of top and left should be modified.
		event:'click',//on which event to react.
		stop:true//avoid queuing animations 
		/*
		lock:false,//ignore events if already animating
		lazy:false,//if true, links can be added later, and will still work.
		target:null, //what to scroll (selector or element). keep it null if want to scroll the whole window.
		filter:null, //filter some anchors out of the matched elements.
		hash: false//if true, the hash of the selected link, will appear on the address bar.
		*/
	};

	//if the url contains a hash, it will scroll to the pointed element
	$localscroll.hash = function( settings ){
		settings = $.extend( {}, $localscroll.defaults, settings );
		settings.hash = false;//can't be true
		if( location.hash )
			settimeout(function(){ scroll( 0, location, settings ); }, 0 );//better wrapped with a settimeout
	};

	$.fn.localscroll = function( settings ){
		settings = $.extend( {}, $localscroll.defaults, settings );

		return ( settings.persistent || settings.lazy ) 
				? this.bind( settings.event, function( e ){//use event delegation, more links can be added later.
					var a = $([e.target, e.target.parentnode]).filter(filter)[0];//if a valid link was clicked.
					a && scroll( e, a, settings );//do scroll.
				})
				: this.find('a')//bind concretely, to each matching link
						.filter( filter ).bind( settings.event, function(e){
							scroll( e, this, settings );
						}).end()
					.end();

		function filter(){//is this a link that points to an anchor and passes a possible filter ? href is checked to avoid a bug in ff.
			return !!this.href && !!this.hash && this.href.replace(this.hash,'') == uri && (!settings.filter || $(this).is( settings.filter ));
		};
	};

	function scroll( e, link, settings ){
		var id = link.hash.slice(1),
			elem = document.getelementbyid(id) || document.getelementsbyname(id)[0];
		if ( elem ){
			e && e.preventdefault();
			var $target = $( settings.target || $.scrollto.window() );//if none specified, then the window.

			if( settings.lock && $target.is(':animated') ||
			settings.onbefore && settings.onbefore.call(link, e, elem, $target) === false ) return;

			if( settings.stop )
				$target.queue('fx',[]).stop();//remove all its animations
			$target
				.scrollto( elem, settings )//do scroll
				.trigger('notify.serialscroll',[elem]);//notify serialscroll about this change
			if( settings.hash )
				$target.queue(function(){
					location = link.hash;
				});
		}
	};

})( jquery );