/* Client-side access to querystring name=value pairs
	Version 1.2.3
	22 Jun 2005
	Adam Vandenberg
*/
function Querystring(qs) { // optionally pass a querystring to parse
	this.params = new Object()
	this.get=Querystring_get;
	this.set=Querystring_set;
	this.comp=Querystring_comp;	
	
	if (qs == null)
		qs=location.search.substring(1,location.search.length)

	if (qs.length == 0) return

// Turn <plus> back to <space>
// See: http://www.w3.org/TR/REC-html40/interact/forms.html#h-17.13.4.1
	qs = qs.replace(/\+/g, ' ')
	var args = qs.split('&') // parse out name/value pairs separated via &
	
// split out each name=value pair
	for (var i=0;i<args.length;i++) {
		var value;
		var pair = args[i].split('=')
		var name = unescape(pair[0])

		if (pair.length == 2)
			value = decodeURI(pair[1])
		else
			value = name
		if(this.params[name]) {		  
		  try {
		    this.params[name].push(value);
		  } catch(e) {
		    this.params[name] = new Array(this.params[name], value);
		  }		   
		} else
		this.params[name] = value
	}
}

function Querystring_get(key, default_) {
	// This silly looking line changes UNDEFINED to NULL
	if (default_ == null) default_ = null;
	
	var value=this.params[key]
	if (value==null) value=default_;
	
	return value
}

function Querystring_set(key, value) {
	this.params[key] = value;
}

function Querystring_comp() {
    r = '';
	for(var i in this.params)
	  if(!(this.params[i] instanceof Array || typeof this.params[i] == "array"))
	    r += i + '=' + encodeURI(this.params[i])+'&';
	  else 
	    for(var j in this.params[i])
		  r += i + '=' + encodeURI(this.params[i][j])+'&';
   return r;	  
}