/**
 * jQuery.labelify - Display in-textbox hints
 * Stuart Langridge, http://www.kryogenix.org/
 * Released into the public domain
 * Date: 25th June 2008
 * @author Stuart Langridge
 * @version 1.3
 *
 *
 * Basic calling syntax: jQuery("input").labelify();
 * Defaults to taking the in-field label from the field's title attribute
 *
 * You can also pass an options object with the following keys:
 *   text
 *	 "title" to get the in-field label from the field's title attribute 
 *	  (this is the default)
 *	 "label" to get the in-field label from the inner text of the field's label
 *	  (note that the label must be attached to the field with for="fieldid")
 *	 a function which takes one parameter, the input field, and returns
 *	  whatever text it likes
 *
 *   labelledClass
 *	 a class that will be applied to the input field when it contains the
 *	  label and removed when it contains user input. Defaults to blank.
 *  
 */
jQuery.fn.labelify = function(settings) {
  settings = jQuery.extend({
	text: "title",
	labelledClass: ""
  }, settings);
  var lookups = {
	title: function(input) {
	  return jQuery(input).attr("title");
	},
	label: function(input) {
	  return jQuery("label[for=" + input.id +"]").text();
	}
  };
  var lookup;
  var jQuery_labellified_elements = jQuery(this);
  return jQuery(this).each(function() {
	if (typeof settings.text === "string") {
	  lookup = lookups[settings.text]; // what if not there?
	} else {
	  lookup = settings.text; // what if not a fn?
	};
	// bail if lookup isn't a function or if it returns undefined
	if (typeof lookup !== "function") { return; }
	var lookupval = lookup(this);
	if (!lookupval) { return; }

	// need to strip newlines because the browser strips them
	// if you set textbox.value to a string containing them	
	jQuery(this).data("label",lookup(this).replace(/\n/g,''));
	jQuery(this).focus(function() {
	  if (this.value === jQuery(this).data("label")) {
		this.value = this.defaultValue;
		jQuery(this).removeClass(settings.labelledClass);
	  }
	}).blur(function(){
	  if (this.value === this.defaultValue) {
		this.value = jQuery(this).data("label");
		jQuery(this).addClass(settings.labelledClass);
	  }
	});
	
	var removeValuesOnExit = function() {
	  jQuery_labellified_elements.each(function(){
		if (this.value === jQuery(this).data("label")) {
		  this.value = this.defaultValue;
		  jQuery(this).removeClass(settings.labelledClass);
		}
	  })
	};
	
	jQuery(this).parents("form").submit(removeValuesOnExit);
	jQuery(window).unload(removeValuesOnExit);
	
	if (this.value !== this.defaultValue) {
	  // user already started typing; don't overwrite their work!
	  return;
	}
	// actually set the value
	this.value = jQuery(this).data("label");
	jQuery(this).addClass(settings.labelledClass);

  });
};