/*
 * jQuery Field Plug-in
 *
 * Copyright (c) 2007 Dan G. Switzer, II
 *
 * Dual licensed under the MIT and GPL licenses:
 *   http://www.opensource.org/licenses/mit-license.php
 *   http://www.gnu.org/licenses/gpl.html
 *
 * Revision: 1
 * Version: 0.1
 *
 * NOTES: The getValue() and setValue() methods are designed to be
 * executed on single field (i.e. any field that would share the same
 * "name" attribute--a single text box, a group of checkboxes or radio
 * elements, etc.)
 *
*/
(function($){

	// set the defaults
	var defaults = {
		// use a comma as the string delimiter
		delimiter: ","		
	}

	// set default options	
	$.Field = {
		setDefaults: function(options){
			$.extend(defaults, options);
		}
	}
	

	/*
	 * jQuery.fn.fieldArray()
	 *
	 * returns either an array of values or a jQuery object
	 *
	 * NOTE: This *MAY* break the jQuery chain
	 *
	 * Examples:
	 * $("input[@name='name']").fieldArray();
	 * > Gets the current value of the name text element
	 *
	 * $("input[@name='name']").fieldArray(["Dan G. Switzer, II"]);
	 * > Sets the value of the name text element to "Dan G. Switzer, II"
	 *
	 * $("select[@name='state']").fieldArray();
	 * > Gets the current value of the state text element
	 *
	 * $("select[@name='state']").setValue(["OH","NY","CA"]);
	 * > Sets the selected value of the "state" select element to OH, NY and CA
	 *
	 */
	// this will set/get the values for a field based upon and array
	$.fn.fieldArray = function(v){
		var t = $.type(v);
		
		// if no value supplied, return an array of values
		if( t == "undefined" ) return getValue(this);
		
		// convert the string into an array
		if( t == "string" ) v = v.split(defaults.delimiter);
		
		// set the value -- doesn't break the chaing
		if( t == "array" ) return setValue(this, v);
		
		// if we don't know what do to, don't break the chain
		return this;
	}

	/*
	 * jQuery.fn.getValue()
	 *
	 * returns String - a comma delimited list of values for the field
	 *
	 * NOTE: Breaks the jQuery chain, since it returns a string.
	 *
	 * Examples:
	 * $("input[@name='name']").getValue();
	 * > This would return the value of the name text element
	 *
	 * $("select[@name='state']").getValue();
	 * > This would return the currently selected value of the "state" select element
	 *
	 */
	// the getValue() method -- break the chain
	$.fn.getValue = function(){
		// return the values as a comma-delimited string
		return getValue(this).join(defaults.delimiter);
	}

	/*
	 * getValue()
	 *
	 * returns Array - an array of values for the field
	 *
	 */
	// the getValue() method -- break the chain
	var getValue = function(jq){
		var v = [];

		jq.each(
			function (lc){
				// get the current type
				var t = getType(this);

				switch( t ){
					case "checkbox": case "radio":
						// if the checkbox or radio element is checked
						if( this.checked ) v.push(this.value);
					break;

					case "select":
						if( this.type == "select-one" ){
							v.push( (this.selectedIndex == -1) ? "" : getOptionVal(this[this.selectedIndex]) );
						} else {
							// loop through all element in the array for this field
							for( var i=0; i < this.length; i++ ){
								// if the element is selected, get the selected values
								if( this[i].selected ){
									// append the selected value, if the value property doesn't exist, use the text
									v.push(getOptionVal(this[i]));
								}
							}
						}
					break;

					case "text":
						v.push(this.value);
					break;
				}
			}
		);

		// return the values as an array
		return v;
	}

	/*
	 * setValue()
	 *
	 * returns jQuery object
	 *
	 * NOTE: This does *NOT* break the jQuery chain
	 *
	 * Examples:
	 * $("input[@name='name']").setValue("Dan G. Switzer, II");
	 * > Sets the value of the name text element to "Dan G. Switzer, II"
	 *
	 * $("select[@name='state']").setValue("OH");
	 * > Sets the selected value of the "state" select element to "OH"
	 *
	 */
	// the setValue() method -- does *not* break the chain
	$.fn.setValue = function(v){
		// if no value, set to empty string
		return setValue(this, (!v ? [""] : v.split(defaults.delimiter)));
	}

	/*
	 * setValue()
	 *
	 * returns jQuery object
	 *
	 */
	// the setValue() method -- does *not* break the chain
	var setValue = function(jq, v){

		jq.each(
			function (lc){
				var t = getType(this), x;

				switch( t ){
					case "checkbox": case "radio":
						if( valueExists(v, this.value) ) this.checked = true;
						else this.checked = false;
					break;

					case "select":
						var bSelectOne = (this.type == "select-one");
						var bKeepLooking = true; // if select-one type, then only select the first value found
						// loop through all element in the array for this field
						for( var i=0; i < this.length; i++ ){
							x = getOptionVal(this[i]);
							bSelectItem = valueExists(v, x);
							if( bSelectItem ){
								this[i].selected = true;
								// if a select-one element
								if( bSelectOne ){
									// no need to look farther
									bKeepLooking = false;
									// stop the loop
									break;
								}
							} else if( !bSelectOne ) this[i].selected = false;
						}
						// if a select-one box and nothing selected, then try to select the default value
						if( bSelectOne && bKeepLooking ){
							this[0].selected = true;
						}
					break;

					case "text":
						this.value = v.join(defaults.delimiter);
					break;
				}

			}
		);

		return jq;
	}

	// determines how to process a field
	var getType = function (el){
		var t = el.type;

		switch( t ){
			case "select": case "select-one": case "select-multiple":
				t = "select";
				break;
			case "text": case "hidden": case "textarea": case "password": case "button": case "submit": case "submit":
				t = "text";
				break;
			case "checkbox": case "radio":
				t = t;
				break;
		}
		return t;
	}

	// gets the value of a select element
	var getOptionVal = function (el){
		 return jQuery.browser.msie && !(el.attributes['value'].specified) ? el.text : el.value;
	}

	// checks to see if a value exists in an array
	var valueExists = function (a, v){
		return ($.inArray(v, a) > -1);
	}
	
	$.type = function (o){
		var t = (typeof o).toLowerCase();
		
		var instanceOf = function (o, c) {
			while( o != null ){
				if( o.constructor == c) return true;
				o = o.__proto__;
			}
			return false;
		}
		
		if( t == "object" ){
			if( instanceOf(o, Array) ) t = "array";
			else if( instanceOf(o, Date) ) t = "date";
		}
		return t;
	}

	$.isType = function (o, v){
		return ($.type(o) == String(v).toLowerCase());
	}

})(jQuery);