/* ===========================================================================
 *
 * JQuery URL Parser
 * Version 1.0
 * Parses URLs and provides easy access to information within them.
 *
 * Author: Mark Perkins
 * Author email: mark@allmarkedup.com
 *
 * For full documentation and more go to http://projects.allmarkedup.com/jquery_url_parser/
 *
 * ---------------------------------------------------------------------------
 *
 * CREDITS:
 *
 * Parser based on the Regex-based URI parser by Stephen Levithian.
 * For more information (including a detailed explaination of the differences
 * between the 'loose' and 'strict' pasing modes) visit http://blog.stevenlevithan.com/archives/parseuri
 *
 * ---------------------------------------------------------------------------
 *
 * LICENCE:
 *
 * Released under a MIT Licence. See licence.txt that should have been supplied with this file,
 * or visit http://projects.allmarkedup.com/jquery_url_parser/licence.txt
 *
 * ---------------------------------------------------------------------------
 * 
 * EXAMPLES OF USE:
 *
 * Get the domain name (host) from the current page URL
 * jQuery.url.attr("host")
 *
 * Get the query string value for 'item' for the current page
 * jQuery.url.param("item") // null if it doesn't exist
 *
 * Get the second segment of the URI of the current page
 * jQuery.url.segment(2) // null if it doesn't exist
 *
 * Get the protocol of a manually passed in URL
 * jQuery.url.setUrl("http://allmarkedup.com/").attr("protocol") // returns 'http'
 *
 */
jQuery.url = function()
{
var segments = {};
var parsed = {};
/**
    * Options object. Only the URI and strictMode values can be changed via the setters below.
    */
  var options = {
	url : window.location, // default URI is the page in which the script is running
	
	strictMode: false, // 'loose' parsing by default
	key: ["source","protocol","authority","userInfo","user","password","host","port","relative","path","directory","file","query","anchor"], // keys available to query 
	
	q: {
	name: "queryKey",
	parser: /(?:^|&)([^&=]*)=?([^&]*)/g
	},
	
	parser: {
	strict: /^(?:([^:\/?#]+):)?(?:\/\/((?:(([^:@]*):?([^:@]*))?@)?([^:\/?#]*)(?::(\d*))?))?((((?:[^?#\/]*\/)*)([^?#]*))(?:\?([^#]*))?(?:#(.*))?)/, // more intuitive, fails on relative paths and deviates from specs
	loose:  /^(?:(?![^:@]+:[^:@\/]*@)([^:\/?#.]+):)?(?:\/\/)?((?:(([^:@]*):?([^:@]*))?@)?([^:\/?#]*)(?::(\d*))?)(((\/(?:[^?#](?![^?#\/]*\.[^?#\/.]+(?:[?#]|$)))*\/?)?([^?#\/]*))(?:\?([^#]*))?(?:#(.*))?)/ //less intuitive, more accurate to the specs
	}
	
};
    /**
     * Deals with the parsing of the URI according to the regex above.
  * Written by Steven Levithan - see credits at top.
     */	
var parseUri = function()
{
	str = decodeURI( options.url );
	
	var m = options.parser[ options.strictMode ? "strict" : "loose" ].exec( str );
	var uri = {};
	var i = 14;
	while ( i-- ) {
	uri[ options.key[i] ] = m[i] || "";
	}
	uri[ options.q.name ] = {};
	uri[ options.key[12] ].replace( options.q.parser, function ( $0, $1, $2 ) {
	if ($1) {
		uri[options.q.name][$1] = $2;
	}
	});
	return uri;
};
    /**
     * Returns the value of the passed in key from the parsed URI.
   * 
 * @param string key The key whose value is required
     */	
var key = function( key )
{
	if ( ! parsed.length )
	{
	setUp(); // if the URI has not been parsed yet then do this first...
	} 
	if ( key == "base" )
	{
	if ( parsed.port !== null && parsed.port !== "" )
	{
		return parsed.protocol+"://"+parsed.host+":"+parsed.port+"/";
	}
	else
	{
		return parsed.protocol+"://"+parsed.host+"/";
	}
	}
	return ( parsed[key] === "" ) ? null : parsed[key];
};
/**
     * Returns the value of the required query string parameter.
   * 
 * @param string item The parameter whose value is required
     */	
var param = function( item )
{
	if ( ! parsed.length )
	{
	setUp(); // if the URI has not been parsed yet then do this first...
	}
	return ( parsed.queryKey[item] === null ) ? null : parsed.queryKey[item];
};
    /**
     * 'Constructor' (not really!) function.
     *  Called whenever the URI changes to kick off re-parsing of the URI and splitting it up into segments. 
     */
var setUp = function()
{
	parsed = parseUri();
	
	getSegments();
};
    /**
     * Splits up the body of the URI into segments (i.e. sections delimited by '/')
     */
var getSegments = function()
{
	var p = parsed.path;
	segments = []; // clear out segments array
	segments = parsed.path.length == 1 ? {} : ( p.charAt( p.length - 1 ) == "/" ? p.substring( 1, p.length - 1 ) : path = p.substring( 1 ) ).split("/");
};
return {
	
    /**
     * Sets the parsing mode - either strict or loose. Set to loose by default.
     *
     * @param string mode The mode to set the parser to. Anything apart from a value of 'strict' will set it to loose!
     */
	setMode : function( mode )
	{
	strictMode = mode == "strict" ? true : false;
	return this;
	},
	
	/**
     * Sets URI to parse if you don't want to to parse the current page's URI.
	 * Calling the function with no value for newUri resets it to the current page's URI.
     *
     * @param string newUri The URI to parse.
     */	
	setUrl : function( newUri )
	{
	options.url = newUri === undefined ? window.location : newUri;
	setUp();
	return this;
	},	
	
	/**
     * Returns the value of the specified URI segment. Segments are numbered from 1 to the number of segments.
	 * For example the URI http://test.com/about/company/ segment(1) would return 'about'.
	 *
	 * If no integer is passed into the function it returns the number of segments in the URI.
     *
     * @param int pos The position of the segment to return. Can be empty.
     */
	segment : function( pos )
	{
	if ( ! parsed.length )
	{
		setUp(); // if the URI has not been parsed yet then do this first...
	} 
	if ( pos === undefined )
	{
		return segments.length;
	}
	return ( segments[pos] === "" || segments[pos] === undefined ) ? null : segments[pos];
	},
	
	attr : key, // provides public access to private 'key' function - see above
	
	param : param // provides public access to private 'param' function - see above
	
};
}();